kits/interface/TextView.cpp

/*
 * Copyright 2001-2014 Haiku, Inc. All rights reserved.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *		Stephan Aßmus, superstippi@gmx.de
 *		Stefano Ceccherini, stefano.ceccherini@gmail.com
 *		Marc Flerackers, mflerackers@androme.be
 *		Hiroshi Lockheimer (BTextView is based on his STEEngine)
 *		John Scipione, jscipione@gmail.com
 *		Oliver Tappe, zooey@hirschkaefer.de
 */


// TODOs:
// - Consider using BObjectList instead of BList
// 	 for disallowed characters (it would remove a lot of reinterpret_casts)
// - Check for correctness and possible optimizations the calls to _Refresh(),
// 	 to refresh only changed parts of text (currently we often redraw the whole
//   text)

// Known Bugs:
// - Double buffering doesn't work well (disabled by default)

#include <stdio.h>
#include <stdlib.h>
#include <new>

#include <Application.h>
#include <Beep.h>
#include <Bitmap.h>
#include <Clipboard.h>
#include <Debug.h>
#include <Entry.h>
#include <Input.h>
#include <LayoutBuilder.h>
#include <LayoutUtils.h>
#include <MessageRunner.h>
#include <Path.h>
#include <PopUpMenu.h>
#include <PropertyInfo.h>
#include <Region.h>
#include <ScrollBar.h>
#include <SystemCatalog.h>
#include <TextView.h>
#include <Window.h>

#include <binary_compatibility/Interface.h>

#include "InlineInput.h"
#include "LineBuffer.h"
#include "StyleBuffer.h"
#include "TextGapBuffer.h"
#include "UndoBuffer.h"
#include "WidthBuffer.h"


using namespace std;
using BPrivate::gSystemCatalog;


#undef B_TRANSLATION_CONTEXT
#define B_TRANSLATION_CONTEXT "TextView"


#define TRANSLATE(str) \
	gSystemCatalog.GetString(B_TRANSLATE_MARK(str), "TextView")

#undef TRACE
#undef CALLED
//#define TRACE_TEXT_VIEW
#ifdef TRACE_TEXT_VIEW
#	include <FunctionTracer.h>
	static int32 sFunctionDepth = -1;
#	define CALLED(x...)	FunctionTracer _ft("BTextView", __FUNCTION__, \
							sFunctionDepth)
#	define TRACE(x...)	{ BString _to; \
							_to.Append(' ', (sFunctionDepth + 1) * 2); \
							printf("%s", _to.String()); printf(x); }
#else
#	define CALLED(x...)
#	define TRACE(x...)
#endif


#define USE_WIDTHBUFFER 1
#define USE_DOUBLEBUFFERING 0


struct flattened_text_run {
	int32	offset;
	font_family	family;
	font_style style;
	float	size;
	float	shear;		/* typically 90.0 */
	uint16	face;		/* typically 0 */
	uint8	red;
	uint8	green;
	uint8	blue;
	uint8	alpha;		/* 255 == opaque */
	uint16	_reserved_;	/* 0 */
};

struct flattened_text_run_array {
	uint32	magic;
	uint32	version;
	int32	count;
	flattened_text_run styles[1];
};

static const uint32 kFlattenedTextRunArrayMagic = 'Ali!';
static const uint32 kFlattenedTextRunArrayVersion = 0;


enum {
	CHAR_CLASS_DEFAULT,
	CHAR_CLASS_WHITESPACE,
	CHAR_CLASS_GRAPHICAL,
	CHAR_CLASS_QUOTE,
	CHAR_CLASS_PUNCTUATION,
	CHAR_CLASS_PARENS_OPEN,
	CHAR_CLASS_PARENS_CLOSE,
	CHAR_CLASS_END_OF_TEXT
};


class BTextView::TextTrackState {
public:
	TextTrackState(BMessenger messenger);
	~TextTrackState();

	void SimulateMouseMovement(BTextView* view);

public:
	int32				clickOffset;
	bool				shiftDown;
	BRect				selectionRect;
	BPoint				where;

	int32				anchor;
	int32				selStart;
	int32				selEnd;

private:
	BMessageRunner*		fRunner;
};


struct BTextView::LayoutData {
	LayoutData()
		: leftInset(0),
		  topInset(0),
		  rightInset(0),
		  bottomInset(0),
		  valid(false)
	{
	}

	void UpdateInsets(const BRect& bounds, const BRect& textRect)
	{
		// we disallow negative insets, as they would cause parts of the
		// text to be hidden
		leftInset = textRect.left >= bounds.left
			? textRect.left - bounds.left
			: 0;
		topInset = textRect.top >= bounds.top
			? textRect.top - bounds.top
			: 0;
		rightInset = bounds.right >= textRect.right
			? bounds.right - textRect.right
			: leftInset;
		bottomInset = bounds.bottom >= textRect.bottom
			? bounds.bottom - textRect.bottom
			: topInset;
	}

	float				leftInset;
	float				topInset;
	float				rightInset;
	float				bottomInset;

	BSize				min;
	BSize				preferred;
	bool				valid;
};


static const rgb_color kBlackColor = { 0, 0, 0, 255 };
static const rgb_color kBlueInputColor = { 152, 203, 255, 255 };
static const rgb_color kRedInputColor = { 255, 152, 152, 255 };

static const float kHorizontalScrollBarStep = 10.0;
static const float kVerticalScrollBarStep = 12.0;

static const int32 kMsgNavigateArrow = '_NvA';
static const int32 kMsgNavigatePage  = '_NvP';


static property_info sPropertyList[] = {
	{
		"selection",
		{ B_GET_PROPERTY, 0 },
		{ B_DIRECT_SPECIFIER, 0 },
		"Returns the current selection.", 0,
		{ B_INT32_TYPE, 0 }
	},
	{
		"selection",
		{ B_SET_PROPERTY, 0 },
		{ B_DIRECT_SPECIFIER, 0 },
		"Sets the current selection.", 0,
		{ B_INT32_TYPE, 0 }
	},
	{
		"Text",
		{ B_COUNT_PROPERTIES, 0 },
		{ B_DIRECT_SPECIFIER, 0 },
		"Returns the length of the text in bytes.", 0,
		{ B_INT32_TYPE, 0 }
	},
	{
		"Text",
		{ B_GET_PROPERTY, 0 },
		{ B_RANGE_SPECIFIER, B_REVERSE_RANGE_SPECIFIER, 0 },
		"Returns the text in the specified range in the BTextView.", 0,
		{ B_STRING_TYPE, 0 }
	},
	{
		"Text",
		{ B_SET_PROPERTY, 0 },
		{ B_RANGE_SPECIFIER, B_REVERSE_RANGE_SPECIFIER, 0 },
		"Removes or inserts text into the specified range in the BTextView.", 0,
		{ B_STRING_TYPE, 0 }
	},
	{
		"text_run_array",
		{ B_GET_PROPERTY, 0 },
		{ B_RANGE_SPECIFIER, B_REVERSE_RANGE_SPECIFIER, 0 },
		"Returns the style information for the text in the specified range in "
			"the BTextView.", 0,
		{ B_RAW_TYPE, 0 },
	},
	{
		"text_run_array",
		{ B_SET_PROPERTY, 0 },
		{ B_RANGE_SPECIFIER, B_REVERSE_RANGE_SPECIFIER, 0 },
		"Sets the style information for the text in the specified range in the "
			"BTextView.", 0,
		{ B_RAW_TYPE, 0 },
	},
	{ 0 }
};


BTextView::BTextView(BRect frame, const char* name, BRect textRect,
		uint32 resizeMask, uint32 flags)
	: BView(frame, name, resizeMask,
		flags | B_FRAME_EVENTS | B_PULSE_NEEDED | B_INPUT_METHOD_AWARE)
{
	_InitObject(textRect, NULL, NULL);
}


BTextView::BTextView(BRect frame, const char* name, BRect textRect,
		const BFont* initialFont, const rgb_color* initialColor,
		uint32 resizeMask, uint32 flags)
	: BView(frame, name, resizeMask,
		flags | B_FRAME_EVENTS | B_PULSE_NEEDED | B_INPUT_METHOD_AWARE)
{
	_InitObject(textRect, initialFont, initialColor);
}


BTextView::BTextView(const char* name, uint32 flags)
	: BView(name, flags | B_FRAME_EVENTS | B_PULSE_NEEDED
		| B_INPUT_METHOD_AWARE)
{
	_InitObject(Bounds(), NULL, NULL);
}


BTextView::BTextView(const char* name, const BFont* initialFont,
	const rgb_color* initialColor, uint32 flags)
	: BView(name, flags | B_FRAME_EVENTS | B_PULSE_NEEDED
		| B_INPUT_METHOD_AWARE)
{
	_InitObject(Bounds(), initialFont, initialColor);
}


BTextView::BTextView(BMessage* archive)
	: BView(archive)
{
	CALLED();
	BRect rect;

	if (archive->FindRect("_trect", &rect) != B_OK)
		rect.Set(0, 0, 0, 0);

	_InitObject(rect, NULL, NULL);

	const char* text = NULL;
	if (archive->FindString("_text", &text) == B_OK)
		SetText(text);

	int32 flag, flag2;
	if (archive->FindInt32("_align", &flag) == B_OK)
		SetAlignment((alignment)flag);

	float value;

	if (archive->FindFloat("_tab", &value) == B_OK)
		SetTabWidth(value);

	if (archive->FindInt32("_col_sp", &flag) == B_OK)
		SetColorSpace((color_space)flag);

	if (archive->FindInt32("_max", &flag) == B_OK)
		SetMaxBytes(flag);

	if (archive->FindInt32("_sel", &flag) == B_OK &&
		archive->FindInt32("_sel", &flag2) == B_OK)
		Select(flag, flag2);

	bool toggle;

	if (archive->FindBool("_stylable", &toggle) == B_OK)
		SetStylable(toggle);

	if (archive->FindBool("_auto_in", &toggle) == B_OK)
		SetAutoindent(toggle);

	if (archive->FindBool("_wrap", &toggle) == B_OK)
		SetWordWrap(toggle);

	if (archive->FindBool("_nsel", &toggle) == B_OK)
		MakeSelectable(!toggle);

	if (archive->FindBool("_nedit", &toggle) == B_OK)
		MakeEditable(!toggle);

	ssize_t disallowedCount = 0;
	const int32* disallowedChars = NULL;
	if (archive->FindData("_dis_ch", B_RAW_TYPE,
		(const void**)&disallowedChars, &disallowedCount) == B_OK) {

		fDisallowedChars = new BList;
		disallowedCount /= sizeof(int32);
		for (int32 x = 0; x < disallowedCount; x++) {
			fDisallowedChars->AddItem(
				reinterpret_cast<void*>(disallowedChars[x]));
		}
	}

	ssize_t runSize = 0;
	const void* flattenedRun = NULL;

	if (archive->FindData("_runs", B_RAW_TYPE, &flattenedRun, &runSize)
			== B_OK) {
		text_run_array* runArray = UnflattenRunArray(flattenedRun,
			(int32*)&runSize);
		if (runArray) {
			SetRunArray(0, TextLength(), runArray);
			FreeRunArray(runArray);
		}
	}
}


BTextView::~BTextView()
{
	_CancelInputMethod();
	_StopMouseTracking();
	_DeleteOffscreen();

	delete fText;
	delete fLines;
	delete fStyles;
	delete fDisallowedChars;
	delete fUndo;
	delete fClickRunner;
	delete fDragRunner;
	delete fLayoutData;
}


// Instantiates a BTextView object from the passed in archive.
BArchivable*
BTextView::Instantiate(BMessage* archive)
{
	CALLED();
	if (validate_instantiation(archive, "BTextView"))
		return new BTextView(archive);
	return NULL;
}


// Archives the object into the data message.
status_t
BTextView::Archive(BMessage* data, bool deep) const
{
	CALLED();
	status_t err = BView::Archive(data, deep);
	if (err == B_OK)
		err = data->AddString("_text", Text());
	if (err == B_OK)
		err = data->AddInt32("_align", fAlignment);
	if (err == B_OK)
		err = data->AddFloat("_tab", fTabWidth);
	if (err == B_OK)
		err = data->AddInt32("_col_sp", fColorSpace);
	if (err == B_OK)
		err = data->AddRect("_trect", fTextRect);
	if (err == B_OK)
		err = data->AddInt32("_max", fMaxBytes);
	if (err == B_OK)
		err = data->AddInt32("_sel", fSelStart);
	if (err == B_OK)
		err = data->AddInt32("_sel", fSelEnd);
	if (err == B_OK)
		err = data->AddBool("_stylable", fStylable);
	if (err == B_OK)
		err = data->AddBool("_auto_in", fAutoindent);
	if (err == B_OK)
		err = data->AddBool("_wrap", fWrap);
	if (err == B_OK)
		err = data->AddBool("_nsel", !fSelectable);
	if (err == B_OK)
		err = data->AddBool("_nedit", !fEditable);

	if (err == B_OK && fDisallowedChars != NULL) {
		err = data->AddData("_dis_ch", B_RAW_TYPE, fDisallowedChars->Items(),
			fDisallowedChars->CountItems() * sizeof(int32));
	}

	if (err == B_OK) {
		int32 runSize = 0;
		text_run_array* runArray = RunArray(0, TextLength());

		void* flattened = FlattenRunArray(runArray, &runSize);
		if (flattened != NULL) {
			data->AddData("_runs", B_RAW_TYPE, flattened, runSize);
			free(flattened);
		} else
			err = B_NO_MEMORY;

		FreeRunArray(runArray);
	}

	return err;
}


// Hook method that is called when the BTextView is added to the
// view hierarchy.
void
BTextView::AttachedToWindow()
{
	BView::AttachedToWindow();

	SetDrawingMode(B_OP_COPY);

	Window()->SetPulseRate(500000);

	fCaretVisible = false;
	fCaretTime = 0;
	fClickCount = 0;
	fClickTime = 0;
	fDragOffset = -1;
	fActive = false;

	_AutoResize(true);

	_UpdateScrollbars();

	SetViewCursor(B_CURSOR_SYSTEM_DEFAULT);
}


// Hook method that is called when the BTextView is removed from the
// view hierarchy.
void
BTextView::DetachedFromWindow()
{
	BView::DetachedFromWindow();
}


// Hook method that is called to draw the contents of the BTextView.
void
BTextView::Draw(BRect updateRect)
{
	// what lines need to be drawn?
	int32 startLine = _LineAt(BPoint(0.0, updateRect.top));
	int32 endLine = _LineAt(BPoint(0.0, updateRect.bottom));

	_DrawLines(startLine, endLine, -1, true);
}


// Hook method that is called when a mouse button is pushed down while
// the cursor is contained in the view.
void
BTextView::MouseDown(BPoint where)
{
	// should we even bother?
	if (!fEditable && !fSelectable)
		return;

	_CancelInputMethod();

	if (!IsFocus())
		MakeFocus();

	_HideCaret();

	_StopMouseTracking();

	int32 modifiers = 0;
	uint32 buttons = 0;
	BMessage* currentMessage = Window()->CurrentMessage();
	if (currentMessage != NULL) {
		currentMessage->FindInt32("modifiers", &modifiers);
		currentMessage->FindInt32("buttons", (int32*)&buttons);
	}

	if (buttons == B_SECONDARY_MOUSE_BUTTON) {
		_ShowContextMenu(where);
		return;
	}

	BMessenger messenger(this);
	fTrackingMouse = new (nothrow) TextTrackState(messenger);
	if (fTrackingMouse == NULL)
		return;

	fTrackingMouse->clickOffset = OffsetAt(where);
	fTrackingMouse->shiftDown = modifiers & B_SHIFT_KEY;
	fTrackingMouse->where = where;

	bigtime_t clickTime = system_time();
	bigtime_t clickSpeed = 0;
	get_click_speed(&clickSpeed);
	bool multipleClick
		= clickTime - fClickTime < clickSpeed
			&& fLastClickOffset == fTrackingMouse->clickOffset;

	fWhere = where;

	SetMouseEventMask(B_POINTER_EVENTS | B_KEYBOARD_EVENTS,
		B_LOCK_WINDOW_FOCUS | B_NO_POINTER_HISTORY);

	if (fSelStart != fSelEnd && !fTrackingMouse->shiftDown && !multipleClick) {
		BRegion region;
		GetTextRegion(fSelStart, fSelEnd, &region);
		if (region.Contains(where)) {
			// Setup things for dragging
			fTrackingMouse->selectionRect = region.Frame();
			fClickCount = 1;
			fClickTime = clickTime;
			fLastClickOffset = OffsetAt(where);
			return;
		}
	}

	if (multipleClick) {
		if (fClickCount > 3) {
			fClickCount = 0;
			fClickTime = 0;
		} else {
			fClickCount++;
			fClickTime = clickTime;
		}
	} else if (!fTrackingMouse->shiftDown) {
		// If no multiple click yet and shift is not pressed, this is an
		// independent first click somewhere into the textview - we initialize
		// the corresponding members for handling potential multiple clicks:
		fLastClickOffset = fCaretOffset = fTrackingMouse->clickOffset;
		fClickCount = 1;
		fClickTime = clickTime;

		// Deselect any previously selected text
		Select(fTrackingMouse->clickOffset, fTrackingMouse->clickOffset);
	}

	if (fClickTime == clickTime) {
		BMessage message(_PING_);
		message.AddInt64("clickTime", clickTime);
		delete fClickRunner;

		BMessenger messenger(this);
		fClickRunner = new (nothrow) BMessageRunner(messenger, &message,
			clickSpeed, 1);
	}


	if (!fSelectable) {
		_StopMouseTracking();
		return;
	}

	int32 offset = fSelStart;
	if (fTrackingMouse->clickOffset > fSelStart)
		offset = fSelEnd;

	fTrackingMouse->anchor = offset;

	MouseMoved(where, B_INSIDE_VIEW, NULL);
}


// Hook method that is called when a mouse button is released while
// the cursor is contained in the view.
void
BTextView::MouseUp(BPoint where)
{
	BView::MouseUp(where);
	_PerformMouseUp(where);

	delete fDragRunner;
	fDragRunner = NULL;
}


// Hook method that is called whenever the mouse cursor enters, exits
// or moves inside the view.
void
BTextView::MouseMoved(BPoint where, uint32 code, const BMessage* message)
{
	// Check if it's a "click'n'move"
	if (_PerformMouseMoved(where, code))
		return;

	switch (code) {
		case B_ENTERED_VIEW:
		case B_INSIDE_VIEW:
			_TrackMouse(where, message, true);
			break;

		case B_EXITED_VIEW:
			_DragCaret(-1);
			if (Window()->IsActive() && message == NULL)
				SetViewCursor(B_CURSOR_SYSTEM_DEFAULT);
			break;

		default:
			BView::MouseMoved(where, code, message);
			break;
	}
}


// Hook method that is called when the window becomes the active window
// or gives up that status.
void
BTextView::WindowActivated(bool state)
{
	BView::WindowActivated(state);

	if (state && IsFocus()) {
		if (!fActive)
			_Activate();
	} else {
		if (fActive)
			_Deactivate();
	}

	BPoint where;
	uint32 buttons;
	GetMouse(&where, &buttons, false);

	if (Bounds().Contains(where))
		_TrackMouse(where, NULL);
}


// Hook method that is called when a key is pressed while the view is
// the focus view of the active window.
void
BTextView::KeyDown(const char* bytes, int32 numBytes)
{
	const char keyPressed = bytes[0];

	if (!fEditable) {
		// only arrow and page keys are allowed
		// (no need to hide the cursor)
		switch (keyPressed) {
			case B_LEFT_ARROW:
			case B_RIGHT_ARROW:
			case B_UP_ARROW:
			case B_DOWN_ARROW:
				_HandleArrowKey(keyPressed);
				break;

			case B_HOME:
			case B_END:
			case B_PAGE_UP:
			case B_PAGE_DOWN:
				_HandlePageKey(keyPressed);
				break;

			default:
				BView::KeyDown(bytes, numBytes);
				break;
		}

		return;
	}

	// hide the cursor and caret
	if (IsFocus())
		be_app->ObscureCursor();
	_HideCaret();

	switch (keyPressed) {
		case B_BACKSPACE:
			_HandleBackspace();
			break;

		case B_LEFT_ARROW:
		case B_RIGHT_ARROW:
		case B_UP_ARROW:
		case B_DOWN_ARROW:
			_HandleArrowKey(keyPressed);
			break;

		case B_DELETE:
			_HandleDelete();
			break;

		case B_HOME:
		case B_END:
		case B_PAGE_UP:
		case B_PAGE_DOWN:
			_HandlePageKey(keyPressed);
			break;

		case B_ESCAPE:
		case B_INSERT:
		case B_FUNCTION_KEY:
			// ignore, pass it up to superclass
			BView::KeyDown(bytes, numBytes);
			break;

		default:
			// if the character is not allowed, bail out.
			if (fDisallowedChars
				&& fDisallowedChars->HasItem(
					reinterpret_cast<void*>((uint32)keyPressed))) {
				beep();
				return;
			}

			_HandleAlphaKey(bytes, numBytes);
			break;
	}

	// draw the caret
	if (fSelStart == fSelEnd)
		_ShowCaret();
}


// Hook method that is called at a set interval.
void
BTextView::Pulse()
{
	if (fActive && fEditable && fSelStart == fSelEnd) {
		if (system_time() > (fCaretTime + 500000.0))
			_InvertCaret();
	}
}


// Hook method that is called when the frame is resized.
void
BTextView::FrameResized(float width, float height)
{
	BView::FrameResized(width, height);
	_UpdateScrollbars();
}


// Highlight or unhighlight the selection when the view gets or loses its
// focus state.
void
BTextView::MakeFocus(bool focusState)
{
	BView::MakeFocus(focusState);

	if (focusState && Window() && Window()->IsActive()) {
		if (!fActive)
			_Activate();
	} else {
		if (fActive)
			_Deactivate();
	}
}


// Hook method that is called each time the BTextView receives a message.
void
BTextView::MessageReceived(BMessage* message)
{
	// TODO: block input if not editable (Andrew)

	// was this message dropped?
	if (message->WasDropped()) {
		BPoint dropOffset;
		BPoint dropPoint = message->DropPoint(&dropOffset);
		ConvertFromScreen(&dropPoint);
		ConvertFromScreen(&dropOffset);
		if (!_MessageDropped(message, dropPoint, dropOffset))
			BView::MessageReceived(message);

		return;
	}

	switch (message->what) {
		case B_CUT:
			if (!IsTypingHidden())
				Cut(be_clipboard);
			else
				beep();
			break;

		case B_COPY:
			if (!IsTypingHidden())
				Copy(be_clipboard);
			else
				beep();
			break;

		case B_PASTE:
			Paste(be_clipboard);
			break;

		case B_UNDO:
			Undo(be_clipboard);
			break;

		case B_SELECT_ALL:
			SelectAll();
			break;

		case B_INPUT_METHOD_EVENT:
		{
			int32 opcode;
			if (message->FindInt32("be:opcode", &opcode) == B_OK) {
				switch (opcode) {
					case B_INPUT_METHOD_STARTED:
					{
						BMessenger messenger;
						if (message->FindMessenger("be:reply_to", &messenger)
								== B_OK) {
							ASSERT(fInline == NULL);
							fInline = new InlineInput(messenger);
						}
						break;
					}

					case B_INPUT_METHOD_STOPPED:
						delete fInline;
						fInline = NULL;
						break;

					case B_INPUT_METHOD_CHANGED:
						if (fInline != NULL)
							_HandleInputMethodChanged(message);
						break;

					case B_INPUT_METHOD_LOCATION_REQUEST:
						if (fInline != NULL)
							_HandleInputMethodLocationRequest();
						break;

					default:
						break;
				}
			}
			break;
		}

		case B_SET_PROPERTY:
		case B_GET_PROPERTY:
		case B_COUNT_PROPERTIES:
		{
			BPropertyInfo propInfo(sPropertyList);
			BMessage specifier;
			const char* property;

			if (message->GetCurrentSpecifier(NULL, &specifier) < B_OK
				|| specifier.FindString("property", &property) < B_OK)
				return;

			if (propInfo.FindMatch(message, 0, &specifier, specifier.what,
					property) < B_OK) {
				BView::MessageReceived(message);
				break;
			}

			BMessage reply;
			bool handled = false;
			switch(message->what) {
				case B_GET_PROPERTY:
					handled = _GetProperty(&specifier, specifier.what, property,
						&reply);
					break;

				case B_SET_PROPERTY:
					handled = _SetProperty(&specifier, specifier.what, property,
						&reply);
					break;

				case B_COUNT_PROPERTIES:
					handled = _CountProperties(&specifier, specifier.what,
						property, &reply);
					break;

				default:
					break;
			}
			if (handled)
				message->SendReply(&reply);
			else
				BView::MessageReceived(message);
			break;
		}

		case _PING_:
		{
			if (message->HasInt64("clickTime")) {
				bigtime_t clickTime;
				message->FindInt64("clickTime", &clickTime);
				if (clickTime == fClickTime) {
					if (fSelStart != fSelEnd && fSelectable) {
						BRegion region;
						GetTextRegion(fSelStart, fSelEnd, &region);
						if (region.Contains(fWhere))
							_TrackMouse(fWhere, NULL);
					}
					delete fClickRunner;
					fClickRunner = NULL;
				}
			} else if (fTrackingMouse) {
				fTrackingMouse->SimulateMouseMovement(this);
				_PerformAutoScrolling();
			}
			break;
		}

		case _DISPOSE_DRAG_:
			if (fEditable)
				_TrackDrag(fWhere);
			break;

		case kMsgNavigateArrow:
		{
			int32 key = message->GetInt32("key", 0);
			int32 modifiers = message->GetInt32("modifiers", 0);
			_HandleArrowKey(key, modifiers);
			break;
		}

		case kMsgNavigatePage:
		{
			int32 key = message->GetInt32("key", 0);
			int32 modifiers = message->GetInt32("modifiers", 0);
			_HandlePageKey(key, modifiers);
			break;
		}

		default:
			BView::MessageReceived(message);
			break;
	}
}


// Returns the proper handler for the passed in scripting \a message.
BHandler*
BTextView::ResolveSpecifier(BMessage* message, int32 index, BMessage* specifier,
	int32 what, const char* property)
{
	BPropertyInfo propInfo(sPropertyList);
	BHandler* target = this;

	if (propInfo.FindMatch(message, index, specifier, what, property) < B_OK) {
		target = BView::ResolveSpecifier(message, index, specifier, what,
			property);
	}

	return target;
}


status_t
BTextView::GetSupportedSuites(BMessage* data)
{
	if (data == NULL)
		return B_BAD_VALUE;

	status_t err = data->AddString("suites", "suite/vnd.Be-text-view");
	if (err != B_OK)
		return err;

	BPropertyInfo prop_info(sPropertyList);
	err = data->AddFlat("messages", &prop_info);

	if (err != B_OK)
		return err;
	return BView::GetSupportedSuites(data);
}


status_t
BTextView::Perform(perform_code code, void* _data)
{
	switch (code) {
		case PERFORM_CODE_MIN_SIZE:
			((perform_data_min_size*)_data)->return_value
				= BTextView::MinSize();
			return B_OK;
		case PERFORM_CODE_MAX_SIZE:
			((perform_data_max_size*)_data)->return_value
				= BTextView::MaxSize();
			return B_OK;
		case PERFORM_CODE_PREFERRED_SIZE:
			((perform_data_preferred_size*)_data)->return_value
				= BTextView::PreferredSize();
			return B_OK;
		case PERFORM_CODE_LAYOUT_ALIGNMENT:
			((perform_data_layout_alignment*)_data)->return_value
				= BTextView::LayoutAlignment();
			return B_OK;
		case PERFORM_CODE_HAS_HEIGHT_FOR_WIDTH:
			((perform_data_has_height_for_width*)_data)->return_value
				= BTextView::HasHeightForWidth();
			return B_OK;
		case PERFORM_CODE_GET_HEIGHT_FOR_WIDTH:
		{
			perform_data_get_height_for_width* data
				= (perform_data_get_height_for_width*)_data;
			BTextView::GetHeightForWidth(data->width, &data->min, &data->max,
				&data->preferred);
			return B_OK;
		}
		case PERFORM_CODE_SET_LAYOUT:
		{
			perform_data_set_layout* data = (perform_data_set_layout*)_data;
			BTextView::SetLayout(data->layout);
			return B_OK;
		}
		case PERFORM_CODE_LAYOUT_INVALIDATED:
		{
			perform_data_layout_invalidated* data
				= (perform_data_layout_invalidated*)_data;
			BTextView::LayoutInvalidated(data->descendants);
			return B_OK;
		}
		case PERFORM_CODE_DO_LAYOUT:
		{
			BTextView::DoLayout();
			return B_OK;
		}
	}

	return BView::Perform(code, _data);
}


void
BTextView::SetText(const char* text, const text_run_array* runs)
{
	SetText(text, text ? strlen(text) : 0, runs);
}


void
BTextView::SetText(const char* text, int32 length, const text_run_array* runs)
{
	_CancelInputMethod();

	// hide the caret/unhilite the selection
	if (fActive) {
		if (fSelStart != fSelEnd) {
			if (fSelectable)
				Highlight(fSelStart, fSelEnd);
		} else
			_HideCaret();
	}

	// remove data from buffer
	if (fText->Length() > 0)
		DeleteText(0, fText->Length());

	if (text != NULL && length > 0)
		InsertText(text, length, 0, runs);

	// recalc line breaks and draw the text
	_Refresh(0, length, false);
	fCaretOffset = fSelStart = fSelEnd = 0;
	ScrollTo(B_ORIGIN);

	// draw the caret
	_ShowCaret();
}


void
BTextView::SetText(BFile* file, int32 offset, int32 length,
	const text_run_array* runs)
{
	CALLED();

	_CancelInputMethod();

	if (!file)
		return;

	if (fText->Length() > 0)
		DeleteText(0, fText->Length());

	fText->InsertText(file, offset, length, 0);

	// update the start offsets of each line below offset
	fLines->BumpOffset(length, _LineAt(offset) + 1);

	// update the style runs
	fStyles->BumpOffset(length, fStyles->OffsetToRun(offset - 1) + 1);

	if (fStylable && runs != NULL)
		SetRunArray(offset, offset + length, runs);
	else {
		// apply null-style to inserted text
		_ApplyStyleRange(offset, offset + length);
	}

	// recalc line breaks and draw the text
	_Refresh(0, length, false);
	fCaretOffset = fSelStart = fSelEnd = 0;
	ScrollToOffset(fSelStart);

	// draw the caret
	_ShowCaret();
}


void
BTextView::Insert(const char* text, const text_run_array* runs)
{
	if (text != NULL)
		_DoInsertText(text, strlen(text), fSelStart, runs);
}


void
BTextView::Insert(const char* text, int32 length, const text_run_array* runs)
{
	if (text != NULL && length > 0)
		_DoInsertText(text, strnlen(text, length), fSelStart, runs);
}


void
BTextView::Insert(int32 offset, const char* text, int32 length,
	const text_run_array* runs)
{
	// pin offset at reasonable values
	if (offset < 0)
		offset = 0;
	else if (offset > fText->Length())
		offset = fText->Length();

	if (text != NULL && length > 0)
		_DoInsertText(text, strnlen(text, length), offset, runs);
}


// Deletes the text within the current selection.
void
BTextView::Delete()
{
	Delete(fSelStart, fSelEnd);
}


// Deletes the text enclosed within the given offsets.
void
BTextView::Delete(int32 startOffset, int32 endOffset)
{
	CALLED();

	// pin offsets at reasonable values
	if (startOffset < 0)
		startOffset = 0;
	else if (startOffset > fText->Length())
		startOffset = fText->Length();
	if (endOffset < 0)
		endOffset = 0;
	else if (endOffset > fText->Length())
		endOffset = fText->Length();

	// anything to delete?
	if (startOffset == endOffset)
		return;

	// hide the caret/unhilite the selection
	if (fActive) {
		if (fSelStart != fSelEnd) {
			if (fSelectable)
				Highlight(fSelStart, fSelEnd);
		} else
			_HideCaret();
	}
	// remove data from buffer
	DeleteText(startOffset, endOffset);

	// Check if the caret needs to be moved
	if (fCaretOffset >= endOffset)
		fCaretOffset -= (endOffset - startOffset);
	else if (fCaretOffset >= startOffset && fCaretOffset < endOffset)
		fCaretOffset = startOffset;

	fSelEnd = fSelStart = fCaretOffset;

	// recalc line breaks and draw what's left
	_Refresh(startOffset, endOffset, false);

	// draw the caret
	_ShowCaret();
}


// Returns the BTextView text as a byte array.
const char*
BTextView::Text() const
{
	return fText->RealText();
}


// Returns the text length of the BTextView text.
int32
BTextView::TextLength() const
{
	return fText->Length();
}


// Fills out buffer with the text of the BTextView starting at offset and
// grabbing at most length bytes.
void
BTextView::GetText(int32 offset, int32 length, char* buffer) const
{
	if (buffer != NULL)
		fText->GetString(offset, length, buffer);
}


// Returns the character at the given offset.
uchar
BTextView::ByteAt(int32 offset) const
{
	if (offset < 0 || offset >= fText->Length())
		return '\0';

	return fText->RealCharAt(offset);
}


// Returns the number of lines that the BTextView object contains.
int32
BTextView::CountLines() const
{
	return fLines->NumLines();
}


// Returns the index of the current line.
int32
BTextView::CurrentLine() const
{
	return LineAt(fSelStart);
}


// Moves the caret to the specified line.
void
BTextView::GoToLine(int32 index)
{
	_CancelInputMethod();
	_HideCaret();
	fSelStart = fSelEnd = fCaretOffset = OffsetAt(index);
	_ShowCaret();
}


// Moves the current selection to the clipboard.
void
BTextView::Cut(BClipboard* clipboard)
{
	_CancelInputMethod();
	if (!fEditable)
		return;
	if (fUndo) {
		delete fUndo;
		fUndo = new CutUndoBuffer(this);
	}
	Copy(clipboard);
	Delete();
}


// Copies the current selection to the clipboard.
void
BTextView::Copy(BClipboard* clipboard)
{
	_CancelInputMethod();

	if (clipboard->Lock()) {
		clipboard->Clear();

		BMessage* clip = clipboard->Data();
		if (clip != NULL) {
			int32 numBytes = fSelEnd - fSelStart;
			const char* text = fText->GetString(fSelStart, &numBytes);
			clip->AddData("text/plain", B_MIME_TYPE, text, numBytes);

			int32 size;
			if (fStylable) {
				text_run_array* runArray = RunArray(fSelStart, fSelEnd, &size);
				clip->AddData("application/x-vnd.Be-text_run_array",
					B_MIME_TYPE, runArray, size);
				FreeRunArray(runArray);
			}
			clipboard->Commit();
		}
		clipboard->Unlock();
	}
}


// Copy the text contained in the clipboard to the BTextView.
void
BTextView::Paste(BClipboard* clipboard)
{
	CALLED();
	_CancelInputMethod();

	if (!fEditable || !clipboard->Lock())
		return;

	BMessage* clip = clipboard->Data();
	if (clip != NULL) {
		const char* text = NULL;
		ssize_t length = 0;

		if (clip->FindData("text/plain", B_MIME_TYPE,
				(const void**)&text, &length) == B_OK) {
			text_run_array* runArray = NULL;
			ssize_t runLength = 0;

			if (fStylable) {
				clip->FindData("application/x-vnd.Be-text_run_array",
					B_MIME_TYPE, (const void**)&runArray, &runLength);
			}

			_FilterDisallowedChars((char*)text, length, runArray);

			if (length < 1) {
				beep();
				clipboard->Unlock();
				return;
			}

			if (fUndo) {
				delete fUndo;
				fUndo = new PasteUndoBuffer(this, text, length, runArray,
					runLength);
			}

			if (fSelStart != fSelEnd)
				Delete();

			Insert(text, length, runArray);
			ScrollToOffset(fSelEnd);
		}
	}

	clipboard->Unlock();
}


// Deletes the currently selected text.
void
BTextView::Clear()
{
	// We always check for fUndo != NULL (not only here),
	// because when fUndo is NULL, undo is deactivated.
	if (fUndo) {
		delete fUndo;
		fUndo = new ClearUndoBuffer(this);
	}

	Delete();
}


// Returns whether or not the BTextView can accept the clipboard data.
bool
BTextView::AcceptsPaste(BClipboard* clipboard)
{
	bool result = false;

	if (fEditable && clipboard && clipboard->Lock()) {
		BMessage* data = clipboard->Data();
		result = data && data->HasData("text/plain", B_MIME_TYPE);
		clipboard->Unlock();
	}

	return result;
}


// Returns whether or not the BTextView can accept the dropped message data.
bool
BTextView::AcceptsDrop(const BMessage* message)
{
	return fEditable && message
		&& message->HasData("text/plain", B_MIME_TYPE);
}


// Selects the text contained within the given offsets.
void
BTextView::Select(int32 startOffset, int32 endOffset)
{
	CALLED();
	if (!fSelectable)
		return;

	_CancelInputMethod();

	// pin offsets at reasonable values
	if (startOffset < 0)
		startOffset = 0;
	else if (startOffset > fText->Length())
		startOffset = fText->Length();
	if (endOffset < 0)
		endOffset = 0;
	else if (endOffset > fText->Length())
		endOffset = fText->Length();

	// a negative selection?
	if (startOffset > endOffset)
		return;

	// is the new selection any different from the current selection?
	if (startOffset == fSelStart && endOffset == fSelEnd)
		return;

	fStyles->InvalidateNullStyle();

	_HideCaret();

	if (startOffset == endOffset) {
		if (fSelStart != fSelEnd) {
			// unhilite the selection
			if (fActive)
				Highlight(fSelStart, fSelEnd);
		}
		fSelStart = fSelEnd = fCaretOffset = startOffset;
		_ShowCaret();
	} else {
		if (fActive) {
			// draw only those ranges that are different
			long start, end;
			if (startOffset != fSelStart) {
				// start of selection has changed
				if (startOffset > fSelStart) {
					start = fSelStart;
					end = startOffset;
				} else {
					start = startOffset;
					end = fSelStart;
				}
				Highlight(start, end);
			}

			if (endOffset != fSelEnd) {
				// end of selection has changed
				if (endOffset > fSelEnd) {
					start = fSelEnd;
					end = endOffset;
				} else {
					start = endOffset;
					end = fSelEnd;
				}
				Highlight(start, end);
			}
		}
		fSelStart = startOffset;
		fSelEnd = endOffset;
	}
}


// Selects all text contained in the BTextView.
void
BTextView::SelectAll()
{
	Select(0, fText->Length());
}


// Fills out outStart and outEnd with the start and end offsets of the
// current selection.
void
BTextView::GetSelection(int32* _start, int32* _end) const
{
	int32 start = 0;
	int32 end = 0;

	if (fSelectable) {
		start = fSelStart;
		end = fSelEnd;
	}

	if (_start)
		*_start = start;
	if (_end)
		*_end = end;
}


void
BTextView::SetFontAndColor(const BFont* font, uint32 mode,
	const rgb_color* color)
{
	SetFontAndColor(fSelStart, fSelEnd, font, mode, color);
}


void
BTextView::SetFontAndColor(int32 startOffset, int32 endOffset,
	const BFont* font, uint32 mode, const rgb_color* color)
{
	CALLED();

	_HideCaret();

	const int32 textLength = fText->Length();

	if (!fStylable) {
		// When the text view is not stylable, we always set the whole text's
		// style and ignore the offsets
		startOffset = 0;
		endOffset = textLength;
	} else {
		// pin offsets at reasonable values
		if (startOffset < 0)
			startOffset = 0;
		else if (startOffset > textLength)
			startOffset = textLength;

		if (endOffset < 0)
			endOffset = 0;
		else if (endOffset > textLength)
			endOffset = textLength;
	}

	// apply the style to the style buffer
	fStyles->InvalidateNullStyle();
	_ApplyStyleRange(startOffset, endOffset, mode, font, color);

	if ((mode & (B_FONT_FAMILY_AND_STYLE | B_FONT_SIZE)) != 0) {
		// TODO: maybe only invalidate the layout (depending on
		// B_SUPPORTS_LAYOUT) and have it _Refresh() automatically?
		InvalidateLayout();
		// recalc the line breaks and redraw with new style
		_Refresh(startOffset, endOffset, false);
	} else {
		// the line breaks wont change, simply redraw
		_RequestDrawLines(_LineAt(startOffset), _LineAt(endOffset));
	}

	_ShowCaret();
}


void
BTextView::GetFontAndColor(int32 offset, BFont* _font,
	rgb_color* _color) const
{
	fStyles->GetStyle(offset, _font, _color);
}


void
BTextView::GetFontAndColor(BFont* _font, uint32* _mode,
	rgb_color* _color, bool* _sameColor) const
{
	fStyles->ContinuousGetStyle(_font, _mode, _color, _sameColor,
		fSelStart, fSelEnd);
}


void
BTextView::SetRunArray(int32 startOffset, int32 endOffset,
	const text_run_array* runs)
{
	CALLED();

	_CancelInputMethod();

	text_run_array oneRun;

	if (!fStylable) {
		// When the text view is not stylable, we always set the whole text's
		// style with the first run and ignore the offsets
		if (runs->count == 0)
			return;

		startOffset = 0;
		endOffset = fText->Length();
		oneRun.count = 1;
		oneRun.runs[0] = runs->runs[0];
		oneRun.runs[0].offset = 0;
		runs = &oneRun;
	} else {
		// pin offsets at reasonable values
		if (startOffset < 0)
			startOffset = 0;
		else if (startOffset > fText->Length())
			startOffset = fText->Length();

		if (endOffset < 0)
			endOffset = 0;
		else if (endOffset > fText->Length())
			endOffset = fText->Length();
	}

	_SetRunArray(startOffset, endOffset, runs);

	_Refresh(startOffset, endOffset, false);
}


// Returns a text_run_array for the text within the given offsets.
text_run_array*
BTextView::RunArray(int32 startOffset, int32 endOffset, int32* _size) const
{
	// pin offsets at reasonable values
	if (startOffset < 0)
		startOffset = 0;
	else if (startOffset > fText->Length())
		startOffset = fText->Length();

	if (endOffset < 0)
		endOffset = 0;
	else if (endOffset > fText->Length())
		endOffset = fText->Length();

	STEStyleRange* styleRange
		= fStyles->GetStyleRange(startOffset, endOffset - 1);
	if (styleRange == NULL)
		return NULL;

	text_run_array* runArray = AllocRunArray(styleRange->count, _size);
	if (runArray != NULL) {
		for (int32 i = 0; i < runArray->count; i++) {
			runArray->runs[i].offset = styleRange->runs[i].offset;
			runArray->runs[i].font = styleRange->runs[i].style.font;
			runArray->runs[i].color = styleRange->runs[i].style.color;
		}
	}

	free(styleRange);

	return runArray;
}


// Returns the line number of the character at the given offset.
int32
BTextView::LineAt(int32 offset) const
{
	// pin offset at reasonable values
	if (offset < 0)
		offset = 0;
	else if (offset > fText->Length())
		offset = fText->Length();

	int32 lineNum = _LineAt(offset);
	if (_IsOnEmptyLastLine(offset))
		lineNum++;
	return lineNum;
}


/// Returns the line number for the passed point.
int32
BTextView::LineAt(BPoint point) const
{
	int32 lineNum = _LineAt(point);
	if ((*fLines)[lineNum + 1]->origin <= point.y - fTextRect.top)
		lineNum++;

	return lineNum;
}


// Returns the location of the character at the given offset.
BPoint
BTextView::PointAt(int32 offset, float* _height) const
{
	// pin offset at reasonable values
	if (offset < 0)
		offset = 0;
	else if (offset > fText->Length())
		offset = fText->Length();

	// TODO: Cleanup.
	int32 lineNum = _LineAt(offset);
	STELine* line = (*fLines)[lineNum];
	float height = 0;

	BPoint result;
	result.x = 0.0;
	result.y = line->origin + fTextRect.top;

	bool onEmptyLastLine = _IsOnEmptyLastLine(offset);

	if (fStyles->NumRuns() == 0) {
		// Handle the case where there is only one line (no text inserted)
		fStyles->SyncNullStyle(0);
		height = _NullStyleHeight();
	} else {
		height = (line + 1)->origin - line->origin;

		if (onEmptyLastLine) {
			// special case: go down one line if offset is at the newline
			// at the end of the buffer ...
			result.y += height;
			// ... and return the height of that (empty) line
			fStyles->SyncNullStyle(offset);
			height = _NullStyleHeight();
		} else {
			int32 length = offset - line->offset;
			result.x += _TabExpandedStyledWidth(line->offset, length);
		}
	}

	if (fAlignment != B_ALIGN_LEFT) {
		float lineWidth = onEmptyLastLine ? 0.0 : LineWidth(lineNum);
		float alignmentOffset = fTextRect.Width() - lineWidth;
		if (fAlignment == B_ALIGN_CENTER)
			alignmentOffset /= 2;
		result.x += alignmentOffset;
	}

	// convert from text rect coordinates
	result.x += fTextRect.left;

	// round up
	result.x = lroundf(result.x);
	result.y = lroundf(result.y);
	if (_height != NULL)
		*_height = height;

	return result;
}


// Returns the offset at the passed in point.
int32
BTextView::OffsetAt(BPoint point) const
{
	const int32 textLength = fText->Length();

	// should we even bother?
	if (point.y >= fTextRect.bottom)
		return textLength;
	else if (point.y < fTextRect.top)
		return 0;

	int32 lineNum = _LineAt(point);
	STELine* line = (*fLines)[lineNum];

#define COMPILE_PROBABLY_BAD_CODE 1

#if COMPILE_PROBABLY_BAD_CODE
	// special case: if point is within the text rect and PixelToLine()
	// tells us that it's on the last line, but if point is actually
	// lower than the bottom of the last line, return the last offset
	// (can happen for newlines)
	if (lineNum == (fLines->NumLines() - 1)) {
		if (point.y >= ((line + 1)->origin + fTextRect.top))
			return textLength;
	}
#endif

	// convert to text rect coordinates
	if (fAlignment != B_ALIGN_LEFT) {
		float alignmentOffset = fTextRect.Width() - LineWidth(lineNum);
		if (fAlignment == B_ALIGN_CENTER)
			alignmentOffset /= 2;
		point.x -= alignmentOffset;
	}

	point.x -= fTextRect.left;
	point.x = max_c(point.x, 0.0);

	// TODO: The following code isn't very efficient, because it always starts
	// from the left end, so when the point is near the right end it's very
	// slow.
	int32 offset = line->offset;
	const int32 limit = (line + 1)->offset;
	float location = 0;
	do {
		const int32 nextInitial = _NextInitialByte(offset);
		const int32 saveOffset = offset;
		float width = 0;
		if (ByteAt(offset) == B_TAB)
			width = _ActualTabWidth(location);
		else
			width = _StyledWidth(saveOffset, nextInitial - saveOffset);
		if (location + width > point.x) {
			if (fabs(location + width - point.x) < fabs(location - point.x))
				offset = nextInitial;
			break;
		}

		location += width;
		offset = nextInitial;
	} while (offset < limit);

	if (offset == (line + 1)->offset) {
		// special case: newlines aren't visible
		// return the offset of the character preceding the newline
		if (ByteAt(offset - 1) == B_ENTER)
			return --offset;

		// special case: return the offset preceding any spaces that
		// aren't at the end of the buffer
		if (offset != textLength && ByteAt(offset - 1) == B_SPACE)
			return --offset;
	}

	return offset;
}


// Returns the offset of the given line.
int32
BTextView::OffsetAt(int32 line) const
{
	if (line < 0)
		return 0;
	if (line > fLines->NumLines())
		return fText->Length();

	return (*fLines)[line]->offset;
}


// Fills out _fromOffset and _toOffset for a sequence of character that
// qualifies as a word starting at offset.
void
BTextView::FindWord(int32 offset, int32* _fromOffset, int32* _toOffset)
{
	if (offset < 0) {
		if (_fromOffset)
			*_fromOffset = 0;
		if (_toOffset)
			*_toOffset = 0;
		return;
	}

	if (offset > fText->Length()) {
		if (_fromOffset)
			*_fromOffset = fText->Length();
		if (_toOffset)
			*_toOffset = fText->Length();
		return;
	}

	if (_fromOffset)
		*_fromOffset = _PreviousWordBoundary(offset);

	if (_toOffset)
		*_toOffset = _NextWordBoundary(offset);
}


// Returns whether or not the character at the given offset can be
// the last character of a line.
bool
BTextView::CanEndLine(int32 offset)
{
	if (offset < 0 || offset > fText->Length())
		return false;

	// TODO: This should be improved using the LocaleKit.
	uint32 classification = _CharClassification(offset);

	// wrapping is always allowed at end of text and at newlines
	if (classification == CHAR_CLASS_END_OF_TEXT || ByteAt(offset) == B_ENTER)
		return true;

	uint32 nextClassification = _CharClassification(offset + 1);
	if (nextClassification == CHAR_CLASS_END_OF_TEXT)
		return true;

	// never separate a punctuation char from its preceeding word
	if (classification == CHAR_CLASS_DEFAULT
		&& nextClassification == CHAR_CLASS_PUNCTUATION) {
		return false;
	}

	if ((classification == CHAR_CLASS_WHITESPACE
			&& nextClassification != CHAR_CLASS_WHITESPACE)
		|| (classification != CHAR_CLASS_WHITESPACE
			&& nextClassification == CHAR_CLASS_WHITESPACE)) {
		return true;
	}

	// allow wrapping after whitespace, unless more whitespace (except for
	// newline) follows
	if (classification == CHAR_CLASS_WHITESPACE
		&& (nextClassification != CHAR_CLASS_WHITESPACE
			|| ByteAt(offset + 1) == B_ENTER)) {
		return true;
	}

	// allow wrapping after punctuation chars, unless more punctuation, closing
	// parens or quotes follow
	if (classification == CHAR_CLASS_PUNCTUATION
		&& nextClassification != CHAR_CLASS_PUNCTUATION
		&& nextClassification != CHAR_CLASS_PARENS_CLOSE
		&& nextClassification != CHAR_CLASS_QUOTE) {
		return true;
	}

	// allow wrapping after quotes, graphical chars and closing parens only if
	// whitespace follows (not perfect, but seems to do the right thing most
	// of the time)
	if ((classification == CHAR_CLASS_QUOTE
			|| classification == CHAR_CLASS_GRAPHICAL
			|| classification == CHAR_CLASS_PARENS_CLOSE)
		&& nextClassification == CHAR_CLASS_WHITESPACE) {
		return true;
	}

	return false;
}


// Returns the width of the line at the given index.
float
BTextView::LineWidth(int32 lineNum) const
{
	if (lineNum < 0 || lineNum >= fLines->NumLines())
		return 0;

	STELine* line = (*fLines)[lineNum];
	int32 length = (line + 1)->offset - line->offset;

	// skip newline at the end of the line, if any, as it does no contribute
	// to the width
	if (ByteAt((line + 1)->offset - 1) == B_ENTER)
		length--;

	return _TabExpandedStyledWidth(line->offset, length);
}


// Returns the height of the line at the given index.
float
BTextView::LineHeight(int32 lineNum) const
{
	float lineHeight = TextHeight(lineNum, lineNum);
	if (lineHeight == 0.0) {
		// We probably don't have text content yet. Take the initial
		// style's font height or fall back to the plain font.
		const BFont* font;
		fStyles->GetNullStyle(&font, NULL);
		if (font == NULL)
			font = be_plain_font;

		font_height fontHeight;
		font->GetHeight(&fontHeight);
		// This is how the height is calculated in _RecalculateLineBreaks().
		lineHeight = ceilf(fontHeight.ascent + fontHeight.descent) + 1;
	}

	return lineHeight;
}


// Returns the height of the text enclosed within the given lines.
float
BTextView::TextHeight(int32 startLine, int32 endLine) const
{
	const int32 numLines = fLines->NumLines();
	if (startLine < 0)
		startLine = 0;
	else if (startLine > numLines - 1)
		startLine = numLines - 1;

	if (endLine < 0)
		endLine = 0;
	else if (endLine > numLines - 1)
		endLine = numLines - 1;

	float height = (*fLines)[endLine + 1]->origin
		- (*fLines)[startLine]->origin;

	if (startLine != endLine && endLine == numLines - 1
		&& fText->RealCharAt(fText->Length() - 1) == B_ENTER) {
		height += (*fLines)[endLine + 1]->origin - (*fLines)[endLine]->origin;
	}

	return ceilf(height);
}


void
BTextView::GetTextRegion(int32 startOffset, int32 endOffset,
	BRegion* outRegion) const
{
	if (!outRegion)
		return;

	outRegion->MakeEmpty();

	// pin offsets at reasonable values
	if (startOffset < 0)
		startOffset = 0;
	else if (startOffset > fText->Length())
		startOffset = fText->Length();
	if (endOffset < 0)
		endOffset = 0;
	else if (endOffset > fText->Length())
		endOffset = fText->Length();

	// return an empty region if the range is invalid
	if (startOffset >= endOffset)
		return;

	float startLineHeight = 0.0;
	float endLineHeight = 0.0;
	BPoint startPt = PointAt(startOffset, &startLineHeight);
	BPoint endPt = PointAt(endOffset, &endLineHeight);

	startLineHeight = ceilf(startLineHeight);
	endLineHeight = ceilf(endLineHeight);

	BRect selRect;

	if (startPt.y == endPt.y) {
		// this is a one-line region
		selRect.left = max_c(startPt.x, fTextRect.left);
		selRect.top = startPt.y;
		selRect.right = endPt.x - 1.0;
		selRect.bottom = endPt.y + endLineHeight - 1.0;
		outRegion->Include(selRect);
	} else {
		// more than one line in the specified offset range
		selRect.left = max_c(startPt.x, fTextRect.left);
		selRect.top = startPt.y;
		selRect.right = fTextRect.right;
		selRect.bottom = startPt.y + startLineHeight - 1.0;
		outRegion->Include(selRect);

		if (startPt.y + startLineHeight < endPt.y) {
			// more than two lines in the range
			selRect.left = fTextRect.left;
			selRect.top = startPt.y + startLineHeight;
			selRect.right = fTextRect.right;
			selRect.bottom = endPt.y - 1.0;
			outRegion->Include(selRect);
		}

		selRect.left = fTextRect.left;
		selRect.top = endPt.y;
		selRect.right = endPt.x - 1.0;
		selRect.bottom = endPt.y + endLineHeight - 1.0;
		outRegion->Include(selRect);
	}
}


// Scrolls the text so that the character at offset is visible.
void
BTextView::ScrollToOffset(int32 offset)
{
	// pin offset at reasonable values
	if (offset < 0)
		offset = 0;
	else if (offset > fText->Length())
		offset = fText->Length();

	BRect bounds = Bounds();
	float lineHeight = 0.0;
	float xDiff = 0.0;
	float yDiff = 0.0;
	BPoint point = PointAt(offset, &lineHeight);

	// horizontal
	float extraSpace = fAlignment == B_ALIGN_LEFT ?
		ceilf(bounds.IntegerWidth() / 2) : 0.0;

	if (point.x < bounds.left)
		xDiff = point.x - bounds.left - extraSpace;
	else if (point.x > bounds.right)
		xDiff = point.x - bounds.right + extraSpace;

	// vertical
	if (point.y < bounds.top)
		yDiff = point.y - bounds.top;
	else if (point.y + lineHeight > bounds.bottom
		&& point.y - lineHeight > bounds.top) {
		yDiff = point.y + lineHeight - bounds.bottom;
	}

	// prevent negative scroll offset
	if (bounds.left + xDiff < 0.0)
		xDiff = -bounds.left;
	if (bounds.top + yDiff < 0.0)
		yDiff = -bounds.top;

	ScrollBy(xDiff, yDiff);
}


// Scrolls the text so that the character that begins the selection is visible.
void
BTextView::ScrollToSelection()
{
	ScrollToOffset(fSelStart);
}


// Highlight the text enclosed within the given offsets.
void
BTextView::Highlight(int32 startOffset, int32 endOffset)
{
	// pin offsets at reasonable values
	if (startOffset < 0)
		startOffset = 0;
	else if (startOffset > fText->Length())
		startOffset = fText->Length();
	if (endOffset < 0)
		endOffset = 0;
	else if (endOffset > fText->Length())
		endOffset = fText->Length();

	if (startOffset >= endOffset)
		return;

	BRegion selRegion;
	GetTextRegion(startOffset, endOffset, &selRegion);

	SetDrawingMode(B_OP_INVERT);
	FillRegion(&selRegion, B_SOLID_HIGH);
	SetDrawingMode(B_OP_COPY);
}


// #pragma mark - configuration


// Sets the BTextView's text frame to the passed in rect.
void
BTextView::SetTextRect(BRect rect)
{
	if (rect == fTextRect)
		return;

	if (!fWrap) {
		rect.right = Bounds().right - fLayoutData->rightInset;
		rect.bottom = Bounds().bottom - fLayoutData->bottomInset;
	}

	fLayoutData->UpdateInsets(Bounds().OffsetToCopy(B_ORIGIN), rect);

	_ResetTextRect();
}


// Returns the BTextView's text frame.
BRect
BTextView::TextRect() const
{
	return fTextRect;
}


void
BTextView::_ResetTextRect()
{
	BRect oldTextRect(fTextRect);
	// reset text rect to bounds minus insets ...
	fTextRect = Bounds().OffsetToCopy(B_ORIGIN);
	fTextRect.left += fLayoutData->leftInset;
	fTextRect.top += fLayoutData->topInset;
	fTextRect.right -= fLayoutData->rightInset;
	fTextRect.bottom -= fLayoutData->bottomInset;

	// and rewrap (potentially adjusting the right and the bottom of the text
	// rect)
	_Refresh(0, TextLength(), false);

	// Make sure that the dirty area outside the text is redrawn too.
	BRegion invalid(oldTextRect | fTextRect);
	invalid.Exclude(fTextRect);
	Invalidate(&invalid);
}


// Sets the insets within the bounds for the BTextView's text frame.
void
BTextView::SetInsets(float left, float top, float right, float bottom)
{
	if (fLayoutData->leftInset == left
		&& fLayoutData->topInset == top
		&& fLayoutData->rightInset == right
		&& fLayoutData->bottomInset == bottom)
		return;

	fLayoutData->leftInset = left;
	fLayoutData->topInset = top;
	fLayoutData->rightInset = right;
	fLayoutData->bottomInset = bottom;

	InvalidateLayout();
	Invalidate();
}


// Fills out the parameters with the BTextView's text insets.
void
BTextView::GetInsets(float* _left, float* _top, float* _right,
	float* _bottom) const
{
	if (_left)
		*_left = fLayoutData->leftInset;
	if (_top)
		*_top = fLayoutData->topInset;
	if (_right)
		*_right = fLayoutData->rightInset;
	if (_bottom)
		*_bottom = fLayoutData->bottomInset;
}


// Sets whether or not the BTextView accepts multiple character styles.
void
BTextView::SetStylable(bool stylable)
{
	fStylable = stylable;
}


// Returns whether or not the BTextView object is stylable.
bool
BTextView::IsStylable() const
{
	return fStylable;
}


// Sets the distance between tab stops in pixels.
void
BTextView::SetTabWidth(float width)
{
	if (width == fTabWidth)
		return;

	fTabWidth = width;

	if (Window() != NULL)
		_Refresh(0, fText->Length(), false);
}


// Returns the tab width of the BTextView.
float
BTextView::TabWidth() const
{
	return fTabWidth;
}


// Sets whether or not the BTextView text is selectable.
void
BTextView::MakeSelectable(bool selectable)
{
	if (selectable == fSelectable)
		return;

	fSelectable = selectable;

	if (fActive && fSelStart != fSelEnd && Window() != NULL)
		Highlight(fSelStart, fSelEnd);
}


// Returns whether or not the text is selectable.
bool
BTextView::IsSelectable() const
{
	return fSelectable;
}


// Sets whether or not the text is editable.
void
BTextView::MakeEditable(bool editable)
{
	if (editable == fEditable)
		return;

	fEditable = editable;
	// TextControls change the color of the text when
	// they are made editable, so we need to invalidate
	// the NULL style here
	// TODO: it works well, but it could be caused by a bug somewhere else
	if (fEditable)
		fStyles->InvalidateNullStyle();
	if (Window() != NULL && fActive) {
		if (!fEditable) {
			_HideCaret();
			_CancelInputMethod();
		}
	}
}


// Returns whether or not the text is editable.
bool
BTextView::IsEditable() const
{
	return fEditable;
}


// Activate or deactivate word wrapping mode.
void
BTextView::SetWordWrap(bool wrap)
{
	if (wrap == fWrap)
		return;

	bool updateOnScreen = fActive && Window() != NULL;
	if (updateOnScreen) {
		// hide the caret, unhilite the selection
		if (fSelStart != fSelEnd) {
			if (fSelectable)
				Highlight(fSelStart, fSelEnd);
		} else
			_HideCaret();
	}

	fWrap = wrap;
	if (wrap)
		_ResetTextRect();
	_Refresh(0, fText->Length(), false);

	if (updateOnScreen) {
		// show the caret, hilite the selection
		if (fSelStart != fSelEnd) {
			if (fSelectable)
				Highlight(fSelStart, fSelEnd);
		} else
			_ShowCaret();
	}
}


// Returns whether or not word wrapping is activated.
bool
BTextView::DoesWordWrap() const
{
	return fWrap;
}


// Sets the maximum number of bytes that the BTextView can contain.
void
BTextView::SetMaxBytes(int32 max)
{
	const int32 textLength = fText->Length();
	fMaxBytes = max;

	if (fMaxBytes < textLength) {
		int32 offset = fMaxBytes;
		// Delete the text after fMaxBytes, but
		// respect multibyte characters boundaries.
		const int32 previousInitial = _PreviousInitialByte(offset);
		if (_NextInitialByte(previousInitial) != offset)
			offset = previousInitial;

		Delete(offset, textLength);
	}
}


// Returns the maximum number of bytes that the BTextView can contain.
int32
BTextView::MaxBytes() const
{
	return fMaxBytes;
}


// Adds the character to the disallowed characters list.
void
BTextView::DisallowChar(uint32 character)
{
	if (fDisallowedChars == NULL)
		fDisallowedChars = new BList;
	if (!fDisallowedChars->HasItem(reinterpret_cast<void*>(character)))
		fDisallowedChars->AddItem(reinterpret_cast<void*>(character));
}


// Removes the \a character from the disallowed characters list.
void
BTextView::AllowChar(uint32 character)
{
	if (fDisallowedChars != NULL)
		fDisallowedChars->RemoveItem(reinterpret_cast<void*>(character));
}


// Sets the way text is aligned within the text frame.
void
BTextView::SetAlignment(alignment align)
{
	// Do a reality check
	if (fAlignment != align &&
			(align == B_ALIGN_LEFT ||
			 align == B_ALIGN_RIGHT ||
			 align == B_ALIGN_CENTER)) {
		fAlignment = align;

		// After setting new alignment, update the view/window
		if (Window() != NULL)
			Invalidate();
	}
}


// Returns the currently set text alignment flag.
alignment
BTextView::Alignment() const
{
	return fAlignment;
}


// Sets whether or not new lines of text are automatically indented.
void
BTextView::SetAutoindent(bool state)
{
	fAutoindent = state;
}


// Returns whether or not automatic indenting is active.
bool
BTextView::DoesAutoindent() const
{
	return fAutoindent;
}


// Set the color space of the offscreen BBitmap object.
void
BTextView::SetColorSpace(color_space colors)
{
	if (colors != fColorSpace && fOffscreen) {
		fColorSpace = colors;
		_DeleteOffscreen();
		_NewOffscreen();
	}
}


// Returns the colorspace set to the offscreen BBitmap object.
color_space
BTextView::ColorSpace() const
{
	return fColorSpace;
}


// Activates and deactivates automatic resizing.
void
BTextView::MakeResizable(bool resize, BView* resizeView)
{
	if (resize) {
		fResizable = true;
		fContainerView = resizeView;

		// Wrapping mode and resizable mode can't live together
		if (fWrap) {
			fWrap = false;

			if (fActive && Window() != NULL) {
				if (fSelStart != fSelEnd) {
					if (fSelectable)
						Highlight(fSelStart, fSelEnd);
				} else
					_HideCaret();
			}
		}
		// We need to reset the right inset, as otherwise the auto-resize would
		// get confused about just how wide the textview needs to be.
		// This seems to be an artefact of how Tracker creates the textview
		// during a rename action.
		fLayoutData->rightInset = fLayoutData->leftInset;
	} else {
		fResizable = false;
		fContainerView = NULL;
		if (fOffscreen)
			_DeleteOffscreen();
		_NewOffscreen();
	}

	_Refresh(0, fText->Length(), false);
}


// Returns whether or not the object is resizable.
bool
BTextView::IsResizable() const
{
	return fResizable;
}


// Enables and disables the undo mechanism.
void
BTextView::SetDoesUndo(bool undo)
{
	if (undo && fUndo == NULL)
		fUndo = new UndoBuffer(this, B_UNDO_UNAVAILABLE);
	else if (!undo && fUndo != NULL) {
		delete fUndo;
		fUndo = NULL;
	}
}


// Returns whether or not the undo mechanism is enabled.
bool
BTextView::DoesUndo() const
{
	return fUndo != NULL;
}


// Enables and disables type hiding.
void
BTextView::HideTyping(bool enabled)
{
	if (enabled)
		Delete(0, fText->Length());

	fText->SetPasswordMode(enabled);
}


// Returns whether or not typing is hidden.
bool
BTextView::IsTypingHidden() const
{
	return fText->PasswordMode();
}


// #pragma mark -


void
BTextView::ResizeToPreferred()
{
	BView::ResizeToPreferred();
}


void
BTextView::GetPreferredSize(float* _width, float* _height)
{
	CALLED();

	_ValidateLayoutData();

	if (_width) {
		float width = Bounds().Width();
		if (width < fLayoutData->min.width
			|| (Flags() & B_SUPPORTS_LAYOUT) != 0) {
			width = fLayoutData->min.width;
		}
		*_width = width;
	}

	if (_height) {
		float height = Bounds().Height();
		if (height < fLayoutData->min.height
			|| (Flags() & B_SUPPORTS_LAYOUT) != 0) {
			height = fLayoutData->min.height;
		}
		*_height = height;
	}
}


BSize
BTextView::MinSize()
{
	CALLED();

	_ValidateLayoutData();
	return BLayoutUtils::ComposeSize(ExplicitMinSize(), fLayoutData->min);
}


BSize
BTextView::MaxSize()
{
	CALLED();

	return BLayoutUtils::ComposeSize(ExplicitMaxSize(),
		BSize(B_SIZE_UNLIMITED, B_SIZE_UNLIMITED));
}


BSize
BTextView::PreferredSize()
{
	CALLED();

	_ValidateLayoutData();
	return BLayoutUtils::ComposeSize(ExplicitPreferredSize(),
		fLayoutData->preferred);
}


bool
BTextView::HasHeightForWidth()
{
	// TODO: When not editable and not embedded in a scroll view, we should
	// assume that all text is supposed to be visible.
	return BView::HasHeightForWidth();
}


void
BTextView::GetHeightForWidth(float width, float* min, float* max,
	float* preferred)
{
	// TODO: See above and implement.
	BView::GetHeightForWidth(width, min, max, preferred);
}


void
BTextView::LayoutInvalidated(bool descendants)
{
	CALLED();

	fLayoutData->valid = false;
}


void
BTextView::DoLayout()
{
	// Bail out, if we shan't do layout.
	if (!(Flags() & B_SUPPORTS_LAYOUT))
		return;

	CALLED();

	// If the user set a layout, we let the base class version call its
	// hook.
	if (GetLayout()) {
		BView::DoLayout();
		return;
	}

	_ValidateLayoutData();

	// validate current size
	BSize size(Bounds().Size());
	if (size.width < fLayoutData->min.width)
		size.width = fLayoutData->min.width;
	if (size.height < fLayoutData->min.height)
		size.height = fLayoutData->min.height;

	_ResetTextRect();
}


void
BTextView::_ValidateLayoutData()
{
	if (fLayoutData->valid)
		return;

	CALLED();

	float lineHeight = ceilf(LineHeight(0));
	TRACE("line height: %.2f\n", lineHeight);

	// compute our minimal size
	BSize min(lineHeight * 3, lineHeight);
	min.width += fLayoutData->leftInset + fLayoutData->rightInset;
	min.height += fLayoutData->topInset + fLayoutData->bottomInset;

	fLayoutData->min = min;

	// compute our preferred size
	fLayoutData->preferred.height = fTextRect.Height()
		+ fLayoutData->topInset + fLayoutData->bottomInset;

	if (fWrap)
		fLayoutData->preferred.width = min.width + 5 * lineHeight;
	else {
		float maxWidth = fLines->MaxWidth();
		if (maxWidth < min.width)
			maxWidth = min.width;

		fLayoutData->preferred.width
			= maxWidth + fLayoutData->leftInset + fLayoutData->rightInset;
	}

	fLayoutData->valid = true;
	ResetLayoutInvalidation();

	TRACE("width: %.2f, height: %.2f\n", min.width, min.height);
}


// #pragma mark -


void
BTextView::AllAttached()
{
	BView::AllAttached();
}


void
BTextView::AllDetached()
{
	BView::AllDetached();
}


/* static */
text_run_array*
BTextView::AllocRunArray(int32 entryCount, int32* outSize)
{
	int32 size = sizeof(text_run_array) + (entryCount - 1) * sizeof(text_run);

	text_run_array* runArray = (text_run_array*)malloc(size);
	if (runArray == NULL) {
		if (outSize != NULL)
			*outSize = 0;
		return NULL;
	}

	memset(runArray, 0, sizeof(size));

	runArray->count = entryCount;

	// Call constructors explicitly as the text_run_array
	// was allocated with malloc (and has to, for backwards
	// compatibility)
	for (int32 i = 0; i < runArray->count; i++) {
		new (&runArray->runs[i].font) BFont;
	}

	if (outSize != NULL)
		*outSize = size;

	return runArray;
}


/* static */
text_run_array*
BTextView::CopyRunArray(const text_run_array* orig, int32 countDelta)
{
	text_run_array* copy = AllocRunArray(countDelta, NULL);
	if (copy != NULL) {
		for (int32 i = 0; i < countDelta; i++) {
			copy->runs[i].offset = orig->runs[i].offset;
			copy->runs[i].font = orig->runs[i].font;
			copy->runs[i].color = orig->runs[i].color;
		}
	}
	return copy;
}


/* static */
void
BTextView::FreeRunArray(text_run_array* array)
{
	if (array == NULL)
		return;

	// Call destructors explicitly
	for (int32 i = 0; i < array->count; i++)
		array->runs[i].font.~BFont();

	free(array);
}


/* static */
void*
BTextView::FlattenRunArray(const text_run_array* runArray, int32* _size)
{
	CALLED();
	int32 size = sizeof(flattened_text_run_array) + (runArray->count - 1)
		* sizeof(flattened_text_run);

	flattened_text_run_array* array = (flattened_text_run_array*)malloc(size);
	if (array == NULL) {
		if (_size)
			*_size = 0;
		return NULL;
	}

	array->magic = B_HOST_TO_BENDIAN_INT32(kFlattenedTextRunArrayMagic);
	array->version = B_HOST_TO_BENDIAN_INT32(kFlattenedTextRunArrayVersion);
	array->count = B_HOST_TO_BENDIAN_INT32(runArray->count);

	for (int32 i = 0; i < runArray->count; i++) {
		array->styles[i].offset = B_HOST_TO_BENDIAN_INT32(
			runArray->runs[i].offset);
		runArray->runs[i].font.GetFamilyAndStyle(&array->styles[i].family,
			&array->styles[i].style);
		array->styles[i].size = B_HOST_TO_BENDIAN_FLOAT(
			runArray->runs[i].font.Size());
		array->styles[i].shear = B_HOST_TO_BENDIAN_FLOAT(
			runArray->runs[i].font.Shear());
		array->styles[i].face = B_HOST_TO_BENDIAN_INT16(
			runArray->runs[i].font.Face());
		array->styles[i].red = runArray->runs[i].color.red;
		array->styles[i].green = runArray->runs[i].color.green;
		array->styles[i].blue = runArray->runs[i].color.blue;
		array->styles[i].alpha = 255;
		array->styles[i]._reserved_ = 0;
	}

	if (_size)
		*_size = size;

	return array;
}


/* static */
text_run_array*
BTextView::UnflattenRunArray(const void* data, int32* _size)
{
	CALLED();
	flattened_text_run_array* array = (flattened_text_run_array*)data;

	if (B_BENDIAN_TO_HOST_INT32(array->magic) != kFlattenedTextRunArrayMagic
		|| B_BENDIAN_TO_HOST_INT32(array->version)
			!= kFlattenedTextRunArrayVersion) {
		if (_size)
			*_size = 0;

		return NULL;
	}

	int32 count = B_BENDIAN_TO_HOST_INT32(array->count);

	text_run_array* runArray = AllocRunArray(count, _size);
	if (runArray == NULL)
		return NULL;

	for (int32 i = 0; i < count; i++) {
		runArray->runs[i].offset = B_BENDIAN_TO_HOST_INT32(
			array->styles[i].offset);

		// Set family and style independently from each other, so that
		// even if the family doesn't exist, we try to preserve the style
		runArray->runs[i].font.SetFamilyAndStyle(array->styles[i].family, NULL);
		runArray->runs[i].font.SetFamilyAndStyle(NULL, array->styles[i].style);

		runArray->runs[i].font.SetSize(B_BENDIAN_TO_HOST_FLOAT(
			array->styles[i].size));
		runArray->runs[i].font.SetShear(B_BENDIAN_TO_HOST_FLOAT(
			array->styles[i].shear));

		uint16 face = B_BENDIAN_TO_HOST_INT16(array->styles[i].face);
		if (face != B_REGULAR_FACE) {
			// Be's version doesn't seem to set this correctly
			runArray->runs[i].font.SetFace(face);
		}

		runArray->runs[i].color.red = array->styles[i].red;
		runArray->runs[i].color.green = array->styles[i].green;
		runArray->runs[i].color.blue = array->styles[i].blue;
		runArray->runs[i].color.alpha = array->styles[i].alpha;
	}

	return runArray;
}


void
BTextView::InsertText(const char* text, int32 length, int32 offset,
	const text_run_array* runs)
{
	CALLED();

	if (length < 0)
		length = 0;

	if (offset < 0)
		offset = 0;
	else if (offset > fText->Length())
		offset = fText->Length();

	if (length > 0) {
		// add the text to the buffer
		fText->InsertText(text, length, offset);

		// update the start offsets of each line below offset
		fLines->BumpOffset(length, _LineAt(offset) + 1);

		// update the style runs
		fStyles->BumpOffset(length, fStyles->OffsetToRun(offset - 1) + 1);

		// offset the caret/selection, if the text was inserted before it
		if (offset <= fSelEnd) {
			fSelStart += length;
			fCaretOffset = fSelEnd = fSelStart;
		}
	}

	if (fStylable && runs != NULL) {
		_SetRunArray(offset, offset + length, runs);
	} else {
		// apply null-style to inserted text
		_ApplyStyleRange(offset, offset + length);
	}
}


void
BTextView::DeleteText(int32 fromOffset, int32 toOffset)
{
	CALLED();

	if (fromOffset < 0)
		fromOffset = 0;
	else if (fromOffset > fText->Length())
		fromOffset = fText->Length();
	if (toOffset < 0)
		toOffset = 0;
	else if (toOffset > fText->Length())
		toOffset = fText->Length();

	if (fromOffset >= toOffset)
		return;

	// set nullStyle to style at beginning of range
	fStyles->InvalidateNullStyle();
	fStyles->SyncNullStyle(fromOffset);

	// remove from the text buffer
	fText->RemoveRange(fromOffset, toOffset);

	// remove any lines that have been obliterated
	fLines->RemoveLineRange(fromOffset, toOffset);

	// remove any style runs that have been obliterated
	fStyles->RemoveStyleRange(fromOffset, toOffset);

	// adjust the selection accordingly, assumes fSelEnd >= fSelStart!
	int32 range = toOffset - fromOffset;
	if (fSelStart >= toOffset) {
		// selection is behind the range that was removed
		fSelStart -= range;
		fSelEnd -= range;
	} else if (fSelStart >= fromOffset && fSelEnd <= toOffset) {
		// the selection is within the range that was removed
		fSelStart = fSelEnd = fromOffset;
	} else if (fSelStart >= fromOffset && fSelEnd > toOffset) {
		// the selection starts within and ends after the range
		// the remaining part is the part that was after the range
		fSelStart = fromOffset;
		fSelEnd = fromOffset + fSelEnd - toOffset;
	} else if (fSelStart < fromOffset && fSelEnd < toOffset) {
		// the selection starts before, but ends within the range
		fSelEnd = fromOffset;
	} else if (fSelStart < fromOffset && fSelEnd >= toOffset) {
		// the selection starts before and ends after the range
		fSelEnd -= range;
	}
}


/*! \brief Undoes the last changes.
	\param clipboard A clipboard to use for the undo operation.
*/
void
BTextView::Undo(BClipboard* clipboard)
{
	if (fUndo)
		fUndo->Undo(clipboard);
}


undo_state
BTextView::UndoState(bool* isRedo) const
{
	return fUndo == NULL ? B_UNDO_UNAVAILABLE : fUndo->State(isRedo);
}


void
BTextView::GetDragParameters(BMessage* drag, BBitmap** bitmap, BPoint* point,
	BHandler** handler)
{
	CALLED();
	if (drag == NULL)
		return;

	// Add originator and action
	drag->AddPointer("be:originator", this);
	drag->AddInt32("be_actions", B_TRASH_TARGET);

	// add the text
	int32 numBytes = fSelEnd - fSelStart;
	const char* text = fText->GetString(fSelStart, &numBytes);
	drag->AddData("text/plain", B_MIME_TYPE, text, numBytes);

	// add the corresponding styles
	int32 size = 0;
	text_run_array* styles = RunArray(fSelStart, fSelEnd, &size);

	if (styles != NULL) {
		drag->AddData("application/x-vnd.Be-text_run_array", B_MIME_TYPE,
			styles, size);

		FreeRunArray(styles);
	}

	if (bitmap != NULL)
		*bitmap = NULL;
	if (handler != NULL)
		*handler = NULL;
}


void BTextView::_ReservedTextView3() {}
void BTextView::_ReservedTextView4() {}
void BTextView::_ReservedTextView5() {}
void BTextView::_ReservedTextView6() {}
void BTextView::_ReservedTextView7() {}
void BTextView::_ReservedTextView8() {}
void BTextView::_ReservedTextView9() {}
void BTextView::_ReservedTextView10() {}
void BTextView::_ReservedTextView11() {}
void BTextView::_ReservedTextView12() {}


// #pragma mark -


/*! \brief Inits the BTextView object.
	\param textRect The BTextView's text rect.
	\param initialFont The font which the BTextView will use.
	\param initialColor The initial color of the text.
*/
void
BTextView::_InitObject(BRect textRect, const BFont* initialFont,
	const rgb_color* initialColor)
{
	BFont font;
	if (initialFont == NULL)
		GetFont(&font);
	else
		font = *initialFont;

	_NormalizeFont(&font);

	if (initialColor == NULL)
		initialColor = &kBlackColor;

	fText = new BPrivate::TextGapBuffer;
	fLines = new LineBuffer;
	fStyles = new StyleBuffer(&font, initialColor);

	fInstalledNavigateCommandWordwiseShortcuts = false;
	fInstalledNavigateOptionWordwiseShortcuts = false;
	fInstalledNavigateOptionLinewiseShortcuts = false;
	fInstalledNavigateHomeEndDocwiseShortcuts = false;

	fInstalledSelectCommandWordwiseShortcuts = false;
	fInstalledSelectOptionWordwiseShortcuts = false;
	fInstalledSelectOptionLinewiseShortcuts = false;
	fInstalledSelectHomeEndDocwiseShortcuts = false;

	// We put these here instead of in the constructor initializer list
	// to have less code duplication, and a single place where to do changes
	// if needed.
	fTextRect = textRect;
		// NOTE: The only places where text rect is changed:
		// * width is possibly adjusted in _AutoResize(),
		// * height is adjusted in _RecalculateLineBreaks().
		// When used within the layout management framework, the
		// text rect is changed to maintain constant insets.
	fMinTextRectWidth = fTextRect.Width();
		// see SetTextRect()
	fSelStart = fSelEnd = 0;
	fCaretVisible = false;
	fCaretTime = 0;
	fCaretOffset = 0;
	fClickCount = 0;
	fClickTime = 0;
	fDragOffset = -1;
	fCursor = 0;
	fActive = false;
	fStylable = false;
	fTabWidth = 28.0;
	fSelectable = true;
	fEditable = true;
	fWrap = true;
	fMaxBytes = INT32_MAX;
	fDisallowedChars = NULL;
	fAlignment = B_ALIGN_LEFT;
	fAutoindent = false;
	fOffscreen = NULL;
	fColorSpace = B_CMAP8;
	fResizable = false;
	fContainerView = NULL;
	fUndo = NULL;
	fInline = NULL;
	fDragRunner = NULL;
	fClickRunner = NULL;
	fTrackingMouse = NULL;

	fLayoutData = new LayoutData;
	fLayoutData->UpdateInsets(Bounds().OffsetToCopy(B_ORIGIN), fTextRect);

	fLastClickOffset = -1;

	SetDoesUndo(true);
}


/*! \brief Called when Backspace key is pressed.
*/
void
BTextView::_HandleBackspace()
{
	if (fUndo) {
		TypingUndoBuffer* undoBuffer = dynamic_cast<TypingUndoBuffer*>(
			fUndo);
		if (!undoBuffer) {
			delete fUndo;
			fUndo = undoBuffer = new TypingUndoBuffer(this);
		}
		undoBuffer->BackwardErase();
	}

	if (fSelStart == fSelEnd) {
		if (fSelStart == 0)
			return;
		else
			fSelStart = _PreviousInitialByte(fSelStart);
	} else
		Highlight(fSelStart, fSelEnd);

	DeleteText(fSelStart, fSelEnd);
	fCaretOffset = fSelEnd = fSelStart;

	_Refresh(fSelStart, fSelEnd, true);
}


// Handles when any arrow key is pressed.
void
BTextView::_HandleArrowKey(uint32 arrowKey, int32 modifiers)
{
	// return if there's nowhere to go
	if (fText->Length() == 0)
		return;

	int32 selStart = fSelStart;
	int32 selEnd = fSelEnd;

	if (modifiers < 0) {
		BMessage* currentMessage = Window()->CurrentMessage();
		if (currentMessage == NULL
			|| currentMessage->FindInt32("modifiers", &modifiers) != B_OK) {
			modifiers = 0;
		}
	}

	bool shiftKeyDown   = (modifiers & B_SHIFT_KEY)   != 0;
	bool controlKeyDown = (modifiers & B_CONTROL_KEY) != 0;
	bool optionKeyDown  = (modifiers & B_OPTION_KEY)  != 0;
	bool commandKeyDown = (modifiers & B_COMMAND_KEY) != 0;

	int32 lastClickOffset = fCaretOffset;

	switch (arrowKey) {
		case B_LEFT_ARROW:
			if (!fEditable)
				_ScrollBy(-1 * kHorizontalScrollBarStep, 0);
			else if (fSelStart != fSelEnd && !shiftKeyDown)
				fCaretOffset = fSelStart;
			else {
				if ((commandKeyDown || optionKeyDown) && !controlKeyDown)
					fCaretOffset = _PreviousWordStart(fCaretOffset - 1);
				else
					fCaretOffset = _PreviousInitialByte(fCaretOffset);

				if (shiftKeyDown && fCaretOffset != lastClickOffset) {
					if (fCaretOffset < fSelStart) {
						// extend selection to the left
						selStart = fCaretOffset;
						if (lastClickOffset > fSelStart) {
							// caret has jumped across "anchor"
							selEnd = fSelStart;
						}
					} else {
						// shrink selection from the right
						selEnd = fCaretOffset;
					}
				}
			}
			break;

		case B_RIGHT_ARROW:
			if (!fEditable)
				_ScrollBy(kHorizontalScrollBarStep, 0);
			else if (fSelStart != fSelEnd && !shiftKeyDown)
				fCaretOffset = fSelEnd;
			else {
				if ((commandKeyDown || optionKeyDown) && !controlKeyDown)
					fCaretOffset = _NextWordEnd(fCaretOffset);
				else
					fCaretOffset = _NextInitialByte(fCaretOffset);

				if (shiftKeyDown && fCaretOffset != lastClickOffset) {
					if (fCaretOffset > fSelEnd) {
						// extend selection to the right
						selEnd = fCaretOffset;
						if (lastClickOffset < fSelEnd) {
							// caret has jumped across "anchor"
							selStart = fSelEnd;
						}
					} else {
						// shrink selection from the left
						selStart = fCaretOffset;
					}
				}
			}
			break;

		case B_UP_ARROW:
		{
			if (!fEditable)
				_ScrollBy(0, -1 * kVerticalScrollBarStep);
			else if (fSelStart != fSelEnd && !shiftKeyDown)
				fCaretOffset = fSelStart;
			else {
				if (optionKeyDown && !commandKeyDown && !controlKeyDown)
					fCaretOffset = _PreviousLineStart(fCaretOffset);
				else if (commandKeyDown && !optionKeyDown && !controlKeyDown) {
					_ScrollTo(0, 0);
					fCaretOffset = 0;
				} else {
					float height;
					BPoint point = PointAt(fCaretOffset, &height);
					// find the caret position on the previous
					// line by gently stepping onto this line
					for (int i = 1; i <= height; i++) {
						point.y--;
						int32 offset = OffsetAt(point);
						if (offset < fCaretOffset || i == height) {
							fCaretOffset = offset;
							break;
						}
					}
				}

				if (shiftKeyDown && fCaretOffset != lastClickOffset) {
					if (fCaretOffset < fSelStart) {
						// extend selection to the top
						selStart = fCaretOffset;
						if (lastClickOffset > fSelStart) {
							// caret has jumped across "anchor"
							selEnd = fSelStart;
						}
					} else {
						// shrink selection from the bottom
						selEnd = fCaretOffset;
					}
				}
			}
			break;
		}

		case B_DOWN_ARROW:
		{
			if (!fEditable)
				_ScrollBy(0, kVerticalScrollBarStep);
			else if (fSelStart != fSelEnd && !shiftKeyDown)
				fCaretOffset = fSelEnd;
			else {
				if (optionKeyDown && !commandKeyDown && !controlKeyDown)
					fCaretOffset = _NextLineEnd(fCaretOffset);
				else if (commandKeyDown && !optionKeyDown && !controlKeyDown) {
					_ScrollTo(0, fTextRect.bottom + fLayoutData->bottomInset);
					fCaretOffset = fText->Length();
				} else {
					float height;
					BPoint point = PointAt(fCaretOffset, &height);
					point.y += height;
					fCaretOffset = OffsetAt(point);
				}

				if (shiftKeyDown && fCaretOffset != lastClickOffset) {
					if (fCaretOffset > fSelEnd) {
						// extend selection to the bottom
						selEnd = fCaretOffset;
						if (lastClickOffset < fSelEnd) {
							// caret has jumped across "anchor"
							selStart = fSelEnd;
						}
					} else {
						// shrink selection from the top
						selStart = fCaretOffset;
					}
				}
			}
			break;
		}
	}

	// invalidate the null style
	fStyles->InvalidateNullStyle();

	if (fEditable) {
		if (shiftKeyDown)
			Select(selStart, selEnd);
		else
			Select(fCaretOffset, fCaretOffset);

		// scroll if needed
		ScrollToOffset(fCaretOffset);
	}
}


// Handles when the Delete key is pressed
void
BTextView::_HandleDelete()
{
	if (fUndo) {
		TypingUndoBuffer* undoBuffer = dynamic_cast<TypingUndoBuffer*>(
			fUndo);
		if (!undoBuffer) {
			delete fUndo;
			fUndo = undoBuffer = new TypingUndoBuffer(this);
		}
		undoBuffer->ForwardErase();
	}

	if (fSelStart == fSelEnd) {
		if (fSelEnd == fText->Length())
			return;
		else
			fSelEnd = _NextInitialByte(fSelEnd);
	} else
		Highlight(fSelStart, fSelEnd);

	DeleteText(fSelStart, fSelEnd);
	fCaretOffset = fSelEnd = fSelStart;

	_Refresh(fSelStart, fSelEnd, true);
}


// Handles when the Page Up or Page Down key is pressed.
void
BTextView::_HandlePageKey(uint32 pageKey, int32 modifiers)
{
	if (modifiers < 0) {
		BMessage* currentMessage = Window()->CurrentMessage();
		if (currentMessage == NULL
			|| currentMessage->FindInt32("modifiers", &modifiers) != B_OK) {
			modifiers = 0;
		}
	}

	bool shiftKeyDown   = (modifiers & B_SHIFT_KEY)   != 0;
	bool controlKeyDown = (modifiers & B_CONTROL_KEY) != 0;
	bool optionKeyDown  = (modifiers & B_OPTION_KEY)  != 0;
	bool commandKeyDown = (modifiers & B_COMMAND_KEY) != 0;

	STELine* line = NULL;
	int32 selStart = fSelStart;
	int32 selEnd = fSelEnd;

	int32 lastClickOffset = fCaretOffset;
	switch (pageKey) {
		case B_HOME:
			if (!fEditable) {
				fCaretOffset = 0;
				_ScrollTo(0, 0);
				break;
			} else if (fSelStart != fSelEnd && !shiftKeyDown)
				fCaretOffset = fSelEnd;
			else {
				if (commandKeyDown && !optionKeyDown && !controlKeyDown) {
					_ScrollTo(0, 0);
					fCaretOffset = 0;
				} else {
					// get the start of the last line if caret is on it
					line = (*fLines)[_LineAt(lastClickOffset)];
					fCaretOffset = line->offset;
				}

				if (!shiftKeyDown)
					selStart = selEnd = fCaretOffset;
				else if (fCaretOffset != lastClickOffset) {
					if (fCaretOffset < fSelStart) {
						// extend selection to the left
						selStart = fCaretOffset;
						if (lastClickOffset > fSelStart) {
							// caret has jumped across "anchor"
							selEnd = fSelStart;
						}
					} else {
						// shrink selection from the right
						selEnd = fCaretOffset;
					}
				}
			}
			break;

		case B_END:
			if (!fEditable) {
				fCaretOffset = fText->Length();
				_ScrollTo(0, fTextRect.bottom + fLayoutData->bottomInset);
				break;
			} else if (fSelStart != fSelEnd && !shiftKeyDown)
				fCaretOffset = fSelEnd;
			else {
				if (commandKeyDown && !optionKeyDown && !controlKeyDown) {
					_ScrollTo(0, fTextRect.bottom + fLayoutData->bottomInset);
					fCaretOffset = fText->Length();
				} else {
					// If we are on the last line, just go to the last
					// character in the buffer, otherwise get the starting
					// offset of the next line, and go to the previous character
					int32 currentLine = _LineAt(lastClickOffset);
					if (currentLine + 1 < fLines->NumLines()) {
						line = (*fLines)[currentLine + 1];
						fCaretOffset = _PreviousInitialByte(line->offset);
					} else {
						// This check is needed to avoid moving the cursor
						// when the cursor is on the last line, and that line
						// is empty
						if (fCaretOffset != fText->Length()) {
							fCaretOffset = fText->Length();
							if (ByteAt(fCaretOffset - 1) == B_ENTER)
								fCaretOffset--;
						}
					}
				}

				if (!shiftKeyDown)
					selStart = selEnd = fCaretOffset;
				else if (fCaretOffset != lastClickOffset) {
					if (fCaretOffset > fSelEnd) {
						// extend selection to the right
						selEnd = fCaretOffset;
						if (lastClickOffset < fSelEnd) {
							// caret has jumped across "anchor"
							selStart = fSelEnd;
						}
					} else {
						// shrink selection from the left
						selStart = fCaretOffset;
					}
				}
			}
			break;

		case B_PAGE_UP:
		{
			float lineHeight;
			BPoint currentPos = PointAt(fCaretOffset, &lineHeight);
			BPoint nextPos(currentPos.x,
				currentPos.y + lineHeight - Bounds().Height());
			fCaretOffset = OffsetAt(nextPos);
			nextPos = PointAt(fCaretOffset);
			_ScrollBy(0, nextPos.y - currentPos.y);

			if (!fEditable)
				break;

			if (!shiftKeyDown)
				selStart = selEnd = fCaretOffset;
			else if (fCaretOffset != lastClickOffset) {
				if (fCaretOffset < fSelStart) {
					// extend selection to the top
					selStart = fCaretOffset;
					if (lastClickOffset > fSelStart) {
						// caret has jumped across "anchor"
						selEnd = fSelStart;
					}
				} else {
					// shrink selection from the bottom
					selEnd = fCaretOffset;
				}
			}

			break;
		}

		case B_PAGE_DOWN:
		{
			BPoint currentPos = PointAt(fCaretOffset);
			BPoint nextPos(currentPos.x, currentPos.y + Bounds().Height());
			fCaretOffset = OffsetAt(nextPos);
			nextPos = PointAt(fCaretOffset);
			_ScrollBy(0, nextPos.y - currentPos.y);

			if (!fEditable)
				break;

			if (!shiftKeyDown)
				selStart = selEnd = fCaretOffset;
			else if (fCaretOffset != lastClickOffset) {
				if (fCaretOffset > fSelEnd) {
					// extend selection to the bottom
					selEnd = fCaretOffset;
					if (lastClickOffset < fSelEnd) {
						// caret has jumped across "anchor"
						selStart = fSelEnd;
					}
				} else {
					// shrink selection from the top
					selStart = fCaretOffset;
				}
			}

			break;
		}
	}

	if (fEditable) {
		if (shiftKeyDown)
			Select(selStart, selEnd);
		else
			Select(fCaretOffset, fCaretOffset);

		ScrollToOffset(fCaretOffset);
	}
}


/*! \brief Called when an alphanumeric key is pressed.
	\param bytes The string or character associated with the key.
	\param numBytes The amount of bytes containes in "bytes".
*/
void
BTextView::_HandleAlphaKey(const char* bytes, int32 numBytes)
{
	// TODO: block input if not editable (Andrew)
	if (fUndo) {
		TypingUndoBuffer* undoBuffer = dynamic_cast<TypingUndoBuffer*>(fUndo);
		if (!undoBuffer) {
			delete fUndo;
			fUndo = undoBuffer = new TypingUndoBuffer(this);
		}
		undoBuffer->InputCharacter(numBytes);
	}

	if (fSelStart != fSelEnd) {
		Highlight(fSelStart, fSelEnd);
		DeleteText(fSelStart, fSelEnd);
	}

	if (fAutoindent && numBytes == 1 && *bytes == B_ENTER) {
		int32 start, offset;
		start = offset = OffsetAt(_LineAt(fSelStart));

		while (ByteAt(offset) != '\0' &&
				(ByteAt(offset) == B_TAB || ByteAt(offset) == B_SPACE)
				&& offset < fSelStart)
			offset++;

		_DoInsertText(bytes, numBytes, fSelStart, NULL);
		if (start != offset)
			_DoInsertText(Text() + start, offset - start, fSelStart, NULL);
	} else
		_DoInsertText(bytes, numBytes, fSelStart, NULL);

	fCaretOffset = fSelEnd;

	ScrollToOffset(fCaretOffset);
}


/*! \brief Redraw the text comprised between the two given offsets,
	recalculating linebreaks if needed.
	\param fromOffset The offset from where to refresh.
	\param toOffset The offset where to refresh to.
	\param scroll If true, function will scroll the view to the end offset.
*/
void
BTextView::_Refresh(int32 fromOffset, int32 toOffset, bool scroll)
{
	// TODO: Cleanup
	float saveHeight = fTextRect.Height();
	float saveWidth = fTextRect.Width();
	int32 fromLine = _LineAt(fromOffset);
	int32 toLine = _LineAt(toOffset);
	int32 saveFromLine = fromLine;
	int32 saveToLine = toLine;

	_RecalculateLineBreaks(&fromLine, &toLine);

	// TODO: Maybe there is still something we can do without a window...
	if (!Window())
		return;

	BRect bounds = Bounds();
	float newHeight = fTextRect.Height();

	// if the line breaks have changed, force an erase
	if (fromLine != saveFromLine || toLine != saveToLine
			|| newHeight != saveHeight) {
		fromOffset = -1;
	}

	if (newHeight != saveHeight) {
		// the text area has changed
		if (newHeight < saveHeight)
			toLine = _LineAt(BPoint(0.0f, saveHeight + fTextRect.top));
		else
			toLine = _LineAt(BPoint(0.0f, newHeight + fTextRect.top));
	}

	// draw only those lines that are visible
	int32 fromVisible = _LineAt(BPoint(0.0f, bounds.top));
	int32 toVisible = _LineAt(BPoint(0.0f, bounds.bottom));
	fromLine = max_c(fromVisible, fromLine);
	toLine = min_c(toLine, toVisible);

	_AutoResize(false);

	_RequestDrawLines(fromLine, toLine);

	// erase the area below the text
	BRect eraseRect = bounds;
	eraseRect.top = fTextRect.top + (*fLines)[fLines->NumLines()]->origin;
	eraseRect.bottom = fTextRect.top + saveHeight;
	if (eraseRect.bottom > eraseRect.top && eraseRect.Intersects(bounds)) {
		SetLowColor(ViewColor());
		FillRect(eraseRect, B_SOLID_LOW);
	}

	// update the scroll bars if the text area has changed
	if (newHeight != saveHeight || fMinTextRectWidth != saveWidth)
		_UpdateScrollbars();

	if (scroll)
		ScrollToOffset(fSelEnd);

	Flush();
}


void
BTextView::_RecalculateLineBreaks(int32* startLine, int32* endLine)
{
	CALLED();

	// are we insane?
	*startLine = (*startLine < 0) ? 0 : *startLine;
	*endLine = (*endLine > fLines->NumLines() - 1) ? fLines->NumLines() - 1
		: *endLine;

	int32 textLength = fText->Length();
	int32 lineIndex = (*startLine > 0) ? *startLine - 1 : 0;
	int32 recalThreshold = (*fLines)[*endLine + 1]->offset;
	float width = max_c(fTextRect.Width(), 10);
		// TODO: The minimum width of 10 is a work around for the following
		// problem: If the text rect is too small, we are not calculating any
		// line heights, not even for the first line. Maybe this is a bug
		// in the algorithm, but other places in the class rely on at least
		// the first line to return a valid height. Maybe "10" should really
		// be the width of the very first glyph instead.
	STELine* curLine = (*fLines)[lineIndex];
	STELine* nextLine = curLine + 1;

	do {
		float ascent, descent;
		int32 fromOffset = curLine->offset;
		int32 toOffset = _FindLineBreak(fromOffset, &ascent, &descent, &width);

		curLine->ascent = ascent;
		curLine->width = width;

		// we want to advance at least by one character
		int32 nextOffset = _NextInitialByte(fromOffset);
		if (toOffset < nextOffset && fromOffset < textLength)
			toOffset = nextOffset;

		lineIndex++;
		STELine saveLine = *nextLine;
		if (lineIndex > fLines->NumLines() || toOffset < nextLine->offset) {
			// the new line comes before the old line start, add a line
			STELine newLine;
			newLine.offset = toOffset;
			newLine.origin = ceilf(curLine->origin + ascent + descent) + 1;
			newLine.ascent = 0;
			fLines->InsertLine(&newLine, lineIndex);
		} else {
			// update the existing line
			nextLine->offset = toOffset;
			nextLine->origin = ceilf(curLine->origin + ascent + descent) + 1;

			// remove any lines that start before the current line
			while (lineIndex < fLines->NumLines()
				&& toOffset >= ((*fLines)[lineIndex] + 1)->offset) {
				fLines->RemoveLines(lineIndex + 1);
			}

			nextLine = (*fLines)[lineIndex];
			if (nextLine->offset == saveLine.offset) {
				if (nextLine->offset >= recalThreshold) {
					if (nextLine->origin != saveLine.origin)
						fLines->BumpOrigin(nextLine->origin - saveLine.origin,
							lineIndex + 1);
					break;
				}
			} else {
				if (lineIndex > 0 && lineIndex == *startLine)
					*startLine = lineIndex - 1;
			}
		}

		curLine = (*fLines)[lineIndex];
		nextLine = curLine + 1;
	} while (curLine->offset < textLength);

	// make sure that the sentinel line (which starts at the end of the buffer)
	// has always a width of 0
	(*fLines)[fLines->NumLines()]->width = 0;

	// update the text rect
	float newHeight = TextHeight(0, fLines->NumLines() - 1);
	fTextRect.bottom = fTextRect.top + newHeight;
	if (!fWrap) {
		fMinTextRectWidth = fLines->MaxWidth();
		fTextRect.right = ceilf(fTextRect.left + fMinTextRectWidth);
	}

	*endLine = lineIndex - 1;
	*startLine = min_c(*startLine, *endLine);
}


int32
BTextView::_FindLineBreak(int32 fromOffset, float* _ascent, float* _descent,
	float* inOutWidth)
{
	*_ascent = 0.0;
	*_descent = 0.0;

	const int32 limit = fText->Length();

	// is fromOffset at the end?
	if (fromOffset >= limit) {
		// try to return valid height info anyway
		if (fStyles->NumRuns() > 0) {
			fStyles->Iterate(fromOffset, 1, fInline, NULL, NULL, _ascent,
				_descent);
		} else {
			if (fStyles->IsValidNullStyle()) {
				const BFont* font = NULL;
				fStyles->GetNullStyle(&font, NULL);

				font_height fh;
				font->GetHeight(&fh);
				*_ascent = fh.ascent;
				*_descent = fh.descent + fh.leading;
			}
		}
		*inOutWidth = 0;

		return limit;
	}

	int32 offset = fromOffset;

	if (!fWrap) {
		// Text wrapping is turned off.
		// Just find the offset of the first \n character
		offset = limit - fromOffset;
		fText->FindChar(B_ENTER, fromOffset, &offset);
		offset += fromOffset;
		int32 toOffset = (offset < limit) ? offset : limit;

		*inOutWidth = _TabExpandedStyledWidth(fromOffset, toOffset - fromOffset,
			_ascent, _descent);

		return offset < limit ? offset + 1 : limit;
	}

	bool done = false;
	float ascent = 0.0;
	float descent = 0.0;
	int32 delta = 0;
	float deltaWidth = 0.0;
	float strWidth = 0.0;
	uchar theChar;

	// wrap the text
	while (offset < limit && !done) {
		// find the next line break candidate
		for (; (offset + delta) < limit; delta++) {
			if (CanEndLine(offset + delta)) {
				theChar = fText->RealCharAt(offset + delta);
				if (theChar != B_SPACE && theChar != B_TAB
					&& theChar != B_ENTER) {
					// we are scanning for trailing whitespace below, so we
					// have to skip non-whitespace characters, that can end
					// the line, here
					delta++;
				}
				break;
			}
		}

		int32 deltaBeforeWhitespace = delta;
		// now skip over trailing whitespace, if any
		for (; (offset + delta) < limit; delta++) {
			theChar = fText->RealCharAt(offset + delta);
			if (theChar == B_ENTER) {
				// found a newline, we're done!
				done = true;
				delta++;
				break;
			} else if (theChar != B_SPACE && theChar != B_TAB) {
				// stop at anything else than trailing whitespace
				break;
			}
		}

		delta = max_c(delta, 1);

		// do not include B_ENTER-terminator into width & height calculations
		deltaWidth = _TabExpandedStyledWidth(offset,
								done ? delta - 1 : delta, &ascent, &descent);
		strWidth += deltaWidth;

		if (strWidth >= *inOutWidth) {
			// we've found where the line will wrap
			done = true;

			// we have included trailing whitespace in the width computation
			// above, but that is not being shown anyway, so we try again
			// without the trailing whitespace
			if (delta == deltaBeforeWhitespace) {
				// there is no trailing whitespace, no point in trying
				break;
			}

			// reset string width to start of current run ...
			strWidth -= deltaWidth;

			// ... and compute the resulting width (of visible characters)
			strWidth += _StyledWidth(offset, deltaBeforeWhitespace, NULL, NULL);
			if (strWidth >= *inOutWidth) {
				// width of visible characters exceeds line, we need to wrap
				// before the current "word"
				break;
			}
		}

		*_ascent = max_c(ascent, *_ascent);
		*_descent = max_c(descent, *_descent);

		offset += delta;
		delta = 0;
	}

	if (offset - fromOffset < 1) {
		// there weren't any words that fit entirely in this line
		// force a break in the middle of a word
		*_ascent = 0.0;
		*_descent = 0.0;
		strWidth = 0.0;

		int32 current = fromOffset;
		for (offset = _NextInitialByte(current); current < limit;
				current = offset, offset = _NextInitialByte(offset)) {
			strWidth += _StyledWidth(current, offset - current, &ascent,
				&descent);
			if (strWidth >= *inOutWidth) {
				offset = _PreviousInitialByte(offset);
				break;
			}

			*_ascent = max_c(ascent, *_ascent);
			*_descent = max_c(descent, *_descent);
		}
	}

	return min_c(offset, limit);
}


int32
BTextView::_PreviousLineStart(int32 offset)
{
	if (offset <= 0)
		return 0;

	while (offset > 0) {
		offset = _PreviousInitialByte(offset);
		if (_CharClassification(offset) == CHAR_CLASS_WHITESPACE
			&& ByteAt(offset) == B_ENTER) {
			return offset + 1;
		}
	}

	return offset;
}


int32
BTextView::_NextLineEnd(int32 offset)
{
	int32 textLen = fText->Length();
	if (offset >= textLen)
		return textLen;

	while (offset < textLen) {
		if (_CharClassification(offset) == CHAR_CLASS_WHITESPACE
			&& ByteAt(offset) == B_ENTER) {
			break;
		}
		offset = _NextInitialByte(offset);
	}

	return offset;
}


int32
BTextView::_PreviousWordBoundary(int32 offset)
{
	uint32 charType = _CharClassification(offset);
	int32 previous;
	while (offset > 0) {
		previous = _PreviousInitialByte(offset);
		if (_CharClassification(previous) != charType)
			break;
		offset = previous;
	}

	return offset;
}


int32
BTextView::_NextWordBoundary(int32 offset)
{
	int32 textLen = fText->Length();
	uint32 charType = _CharClassification(offset);
	while (offset < textLen) {
		offset = _NextInitialByte(offset);
		if (_CharClassification(offset) != charType)
			break;
	}

	return offset;
}


int32
BTextView::_PreviousWordStart(int32 offset)
{
	if (offset <= 1)
		return 0;

	--offset;
		// need to look at previous char
	if (_CharClassification(offset) != CHAR_CLASS_DEFAULT) {
		// skip non-word characters
		while (offset > 0) {
			offset = _PreviousInitialByte(offset);
			if (_CharClassification(offset) == CHAR_CLASS_DEFAULT)
				break;
		}
	}
	while (offset > 0) {
		// skip to start of word
		int32 previous = _PreviousInitialByte(offset);
		if (_CharClassification(previous) != CHAR_CLASS_DEFAULT)
			break;
		offset = previous;
	}

	return offset;
}


int32
BTextView::_NextWordEnd(int32 offset)
{
	int32 textLen = fText->Length();
	if (_CharClassification(offset) != CHAR_CLASS_DEFAULT) {
		// skip non-word characters
		while (offset < textLen) {
			offset = _NextInitialByte(offset);
			if (_CharClassification(offset) == CHAR_CLASS_DEFAULT)
				break;
		}
	}
	while (offset < textLen) {
		// skip to end of word
		offset = _NextInitialByte(offset);
		if (_CharClassification(offset) != CHAR_CLASS_DEFAULT)
			break;
	}

	return offset;
}


// Returns the width used by the characters starting at the given
// offset with the given length, expanding all tab characters as needed.
float
BTextView::_TabExpandedStyledWidth(int32 offset, int32 length, float* _ascent,
	float* _descent) const
{
	float ascent = 0.0;
	float descent = 0.0;
	float maxAscent = 0.0;
	float maxDescent = 0.0;

	float width = 0.0;
	int32 numBytes = length;
	bool foundTab = false;
	do {
		foundTab = fText->FindChar(B_TAB, offset, &numBytes);
		width += _StyledWidth(offset, numBytes, &ascent, &descent);

		if (maxAscent < ascent)
			maxAscent = ascent;
		if (maxDescent < descent)
			maxDescent = descent;

		if (foundTab) {
			width += _ActualTabWidth(width);
			numBytes++;
		}

		offset += numBytes;
		length -= numBytes;
		numBytes = length;
	} while (foundTab && length > 0);

	if (_ascent != NULL)
		*_ascent = maxAscent;
	if (_descent != NULL)
		*_descent = maxDescent;

	return width;
}


// Calculate the width of the text within the given limits.
// fromOffset The offset where to start.
// length The length of the text to examine.
// _ascent A pointer to a float which will contain the maximum ascent.
// _descent A pointer to a float which will contain the maximum descent.
// return The width for the text within the given limits.
float
BTextView::_StyledWidth(int32 fromOffset, int32 length, float* _ascent,
	float* _descent) const
{
	if (length == 0) {
		// determine height of char at given offset, but return empty width
		fStyles->Iterate(fromOffset, 1, fInline, NULL, NULL, _ascent,
			_descent);
		return 0.0;
	}

	float result = 0.0;
	float ascent = 0.0;
	float descent = 0.0;
	float maxAscent = 0.0;
	float maxDescent = 0.0;

	// iterate through the style runs
	const BFont* font = NULL;
	int32 numBytes;
	while ((numBytes = fStyles->Iterate(fromOffset, length, fInline, &font,
			NULL, &ascent, &descent)) != 0) {
		maxAscent = max_c(ascent, maxAscent);
		maxDescent = max_c(descent, maxDescent);

#if USE_WIDTHBUFFER
		// Use _BWidthBuffer_ if possible
		if (BPrivate::gWidthBuffer != NULL) {
			result += BPrivate::gWidthBuffer->StringWidth(*fText, fromOffset,
				numBytes, font);
		} else {
#endif
			const char* text = fText->GetString(fromOffset, &numBytes);
			result += font->StringWidth(text, numBytes);

#if USE_WIDTHBUFFER
		}
#endif

		fromOffset += numBytes;
		length -= numBytes;
	}

	if (_ascent != NULL)
		*_ascent = maxAscent;
	if (_descent != NULL)
		*_descent = maxDescent;

	return result;
}


// Calculate the actual tab width for the given location.
float
BTextView::_ActualTabWidth(float location) const
{
	float tabWidth = fTabWidth - fmod(location, fTabWidth);
	if (round(tabWidth) == 0)
		tabWidth = fTabWidth;

	return tabWidth;
}


void
BTextView::_DoInsertText(const char* text, int32 length, int32 offset,
	const text_run_array* runs)
{
	_CancelInputMethod();

	if (TextLength() + length > MaxBytes())
		return;

	if (fSelStart != fSelEnd)
		Select(fSelStart, fSelStart);

	const int32 textLength = TextLength();
	if (offset > textLength)
		offset = textLength;

	// copy data into buffer
	InsertText(text, length, offset, runs);

	// recalc line breaks and draw the text
	_Refresh(offset, offset + length, false);
}


void
BTextView::_DoDeleteText(int32 fromOffset, int32 toOffset)
{
	CALLED();
}


void
BTextView::_DrawLine(BView* view, const int32 &lineNum,
	const int32 &startOffset, const bool &erase, BRect &eraseRect,
	BRegion &inputRegion)
{
	STELine* line = (*fLines)[lineNum];
	float startLeft = fTextRect.left;
	if (startOffset != -1) {
		if (ByteAt(startOffset) == B_ENTER) {
			// StartOffset is a newline
			startLeft = PointAt(line->offset).x;
		} else
			startLeft = PointAt(startOffset).x;
	}
	else if (fAlignment != B_ALIGN_LEFT) {
		float alignmentOffset = fTextRect.Width() - LineWidth(lineNum);
		if (fAlignment == B_ALIGN_CENTER)
			alignmentOffset /= 2;
		startLeft = fTextRect.left + alignmentOffset;
	}

	int32 length = (line + 1)->offset;
	if (startOffset != -1)
		length -= startOffset;
	else
		length -= line->offset;

	// DrawString() chokes if you draw a newline
	if (ByteAt((line + 1)->offset - 1) == B_ENTER)
		length--;

	view->MovePenTo(startLeft, line->origin + line->ascent + fTextRect.top + 1);

	if (erase) {
		eraseRect.top = line->origin + fTextRect.top;
		eraseRect.bottom = (line + 1)->origin + fTextRect.top;
		view->FillRect(eraseRect, B_SOLID_LOW);
	}

	// do we have any text to draw?
	if (length <= 0)
		return;

	bool foundTab = false;
	int32 tabChars = 0;
	int32 numTabs = 0;
	int32 offset = startOffset != -1 ? startOffset : line->offset;
	const BFont* font = NULL;
	const rgb_color* color = NULL;
	int32 numBytes;
	drawing_mode defaultTextRenderingMode = DrawingMode();
	// iterate through each style on this line
	while ((numBytes = fStyles->Iterate(offset, length, fInline, &font,
			&color)) != 0) {
		view->SetFont(font);
		view->SetHighColor(*color);

		tabChars = min_c(numBytes, length);
		do {
			foundTab = fText->FindChar(B_TAB, offset, &tabChars);
			if (foundTab) {
				do {
					numTabs++;
					if (ByteAt(offset + tabChars + numTabs) != B_TAB)
						break;
				} while ((tabChars + numTabs) < numBytes);
			}

			drawing_mode textRenderingMode = defaultTextRenderingMode;

			if (inputRegion.CountRects() > 0
				&& ((offset <= fInline->Offset()
					&& fInline->Offset() < offset + tabChars)
				|| (fInline->Offset() <= offset
					&& offset < fInline->Offset() + fInline->Length()))) {

				textRenderingMode = B_OP_OVER;

				BRegion textRegion;
				GetTextRegion(offset, offset + length, &textRegion);

				textRegion.IntersectWith(&inputRegion);
				view->PushState();

				// Highlight in blue the inputted text
				view->SetHighColor(kBlueInputColor);
				view->FillRect(textRegion.Frame());

				// Highlight in red the selected part
				if (fInline->SelectionLength() > 0) {
					BRegion selectedRegion;
					GetTextRegion(fInline->Offset()
						+ fInline->SelectionOffset(), fInline->Offset()
						+ fInline->SelectionOffset()
						+ fInline->SelectionLength(), &selectedRegion);

					textRegion.IntersectWith(&selectedRegion);

					view->SetHighColor(kRedInputColor);
					view->FillRect(textRegion.Frame());
				}

				view->PopState();
			}

			int32 returnedBytes = tabChars;
			const char* stringToDraw = fText->GetString(offset, &returnedBytes);
			view->SetDrawingMode(textRenderingMode);
			view->DrawString(stringToDraw, returnedBytes);
			if (foundTab) {
				float penPos = PenLocation().x - fTextRect.left;
				float tabWidth = _ActualTabWidth(penPos);
				if (numTabs > 1)
					tabWidth += ((numTabs - 1) * fTabWidth);

				view->MovePenBy(tabWidth, 0.0);
				tabChars += numTabs;
			}

			offset += tabChars;
			length -= tabChars;
			numBytes -= tabChars;
			tabChars = min_c(numBytes, length);
			numTabs = 0;
		} while (foundTab && tabChars > 0);
	}
}


void
BTextView::_DrawLines(int32 startLine, int32 endLine, int32 startOffset,
	bool erase)
{
	if (!Window())
		return;

	// clip the text
	BRect textRect(fTextRect);
	float minWidth
		= Bounds().Width() - fLayoutData->leftInset - fLayoutData->rightInset;
	if (textRect.Width() < minWidth)
		textRect.right = textRect.left + minWidth;
	BRect clipRect = Bounds() & textRect;
	clipRect.InsetBy(-1, -1);

	BRegion newClip;
	newClip.Set(clipRect);
	ConstrainClippingRegion(&newClip);

	// set the low color to the view color so that
	// drawing to a non-white background will work
	SetLowColor(ViewColor());

	BView* view = NULL;
	if (fOffscreen == NULL)
		view = this;
	else {
		fOffscreen->Lock();
		view = fOffscreen->ChildAt(0);
		view->SetLowColor(ViewColor());
		view->FillRect(view->Bounds(), B_SOLID_LOW);
	}

	long maxLine = fLines->NumLines() - 1;
	if (startLine < 0)
		startLine = 0;
	if (endLine > maxLine)
		endLine = maxLine;

	// TODO: See if we can avoid this
	if (fAlignment != B_ALIGN_LEFT)
		erase = true;

	BRect eraseRect = clipRect;
	int32 startEraseLine = startLine;
	STELine* line = (*fLines)[startLine];

	if (erase && startOffset != -1 && fAlignment == B_ALIGN_LEFT) {
		// erase only to the right of startOffset
		startEraseLine++;
		int32 startErase = startOffset;

		BPoint erasePoint = PointAt(startErase);
		eraseRect.left = erasePoint.x;
		eraseRect.top = erasePoint.y;
		eraseRect.bottom = (line + 1)->origin + fTextRect.top;

		view->FillRect(eraseRect, B_SOLID_LOW);

		eraseRect = clipRect;
	}

	BRegion inputRegion;
	if (fInline != NULL && fInline->IsActive()) {
		GetTextRegion(fInline->Offset(), fInline->Offset() + fInline->Length(),
			&inputRegion);
	}

	//BPoint leftTop(startLeft, line->origin);
	for (int32 lineNum = startLine; lineNum <= endLine; lineNum++) {
		const bool eraseThisLine = erase && lineNum >= startEraseLine;
		_DrawLine(view, lineNum, startOffset, eraseThisLine, eraseRect,
			inputRegion);
		startOffset = -1;
			// Set this to -1 so the next iteration will use the line offset
	}

	// draw the caret/hilite the selection
	if (fActive) {
		if (fSelStart != fSelEnd) {
			if (fSelectable)
				Highlight(fSelStart, fSelEnd);
		} else {
			if (fCaretVisible)
				_DrawCaret(fSelStart, true);
		}
	}

	if (fOffscreen != NULL) {
		view->Sync();
		/*BPoint penLocation = view->PenLocation();
		BRect drawRect(leftTop.x, leftTop.y, penLocation.x, penLocation.y);
		DrawBitmap(fOffscreen, drawRect, drawRect);*/
		fOffscreen->Unlock();
	}

	ConstrainClippingRegion(NULL);
}


void
BTextView::_RequestDrawLines(int32 startLine, int32 endLine)
{
	if (!Window())
		return;

	long maxLine = fLines->NumLines() - 1;

	STELine* from = (*fLines)[startLine];
	STELine* to = endLine == maxLine ? NULL : (*fLines)[endLine + 1];
	BRect invalidRect(Bounds().left, from->origin + fTextRect.top,
		Bounds().right,
		to != NULL ? to->origin + fTextRect.top : fTextRect.bottom);
	Invalidate(invalidRect);
	Window()->UpdateIfNeeded();
}


void
BTextView::_DrawCaret(int32 offset, bool visible)
{
	float lineHeight;
	BPoint caretPoint = PointAt(offset, &lineHeight);
	caretPoint.x = min_c(caretPoint.x, fTextRect.right);

	BRect caretRect;
	caretRect.left = caretRect.right = caretPoint.x;
	caretRect.top = caretPoint.y;
	caretRect.bottom = caretPoint.y + lineHeight - 1;

	if (visible)
		InvertRect(caretRect);
	else
		Invalidate(caretRect);
}


inline void
BTextView::_ShowCaret()
{
	if (fActive && !fCaretVisible && fEditable && fSelStart == fSelEnd)
		_InvertCaret();
}


inline void
BTextView::_HideCaret()
{
	if (fCaretVisible && fSelStart == fSelEnd)
		_InvertCaret();
}


// Hides the caret if it is being shown, and if it's hidden, shows it.
void
BTextView::_InvertCaret()
{
	fCaretVisible = !fCaretVisible;
	_DrawCaret(fSelStart, fCaretVisible);
	fCaretTime = system_time();
}


// Place the dragging caret at the given offset.
// offset The offset (zero based within the object's text) where to
//        place the dragging caret. If it's -1, hide the caret.
void
BTextView::_DragCaret(int32 offset)
{
	// does the caret need to move?
	if (offset == fDragOffset)
		return;

	// hide the previous drag caret
	if (fDragOffset != -1)
		_DrawCaret(fDragOffset, false);

	// do we have a new location?
	if (offset != -1) {
		if (fActive) {
			// ignore if offset is within active selection
			if (offset >= fSelStart && offset <= fSelEnd) {
				fDragOffset = -1;
				return;
			}
		}

		_DrawCaret(offset, true);
	}

	fDragOffset = offset;
}


void
BTextView::_StopMouseTracking()
{
	delete fTrackingMouse;
	fTrackingMouse = NULL;
}


bool
BTextView::_PerformMouseUp(BPoint where)
{
	if (fTrackingMouse == NULL)
		return false;

	if (fTrackingMouse->selectionRect.IsValid())
		Select(fTrackingMouse->clickOffset, fTrackingMouse->clickOffset);

	_StopMouseTracking();
	// adjust cursor if necessary
	_TrackMouse(where, NULL, true);

	return true;
}


bool
BTextView::_PerformMouseMoved(BPoint where, uint32 code)
{
	fWhere = where;

	if (fTrackingMouse == NULL)
		return false;

	int32 currentOffset = OffsetAt(where);
	if (fTrackingMouse->selectionRect.IsValid()) {
		// we are tracking the mouse for drag action, if the mouse has moved
		// to another index or more than three pixels from where it was clicked,
		// we initiate a drag now:
		if (currentOffset != fTrackingMouse->clickOffset
			|| fabs(fTrackingMouse->where.x - where.x) > 3
			|| fabs(fTrackingMouse->where.y - where.y) > 3) {
			_StopMouseTracking();
			_InitiateDrag();
			return true;
		}
		return false;
	}

	switch (fClickCount) {
		case 3:
			// triple click, extend selection linewise
			if (currentOffset <= fTrackingMouse->anchor) {
				fTrackingMouse->selStart
					= (*fLines)[_LineAt(currentOffset)]->offset;
				fTrackingMouse->selEnd = fTrackingMouse->shiftDown
					? fSelEnd
					: (*fLines)[_LineAt(fTrackingMouse->anchor) + 1]->offset;
			} else {
				fTrackingMouse->selStart
					= fTrackingMouse->shiftDown
						? fSelStart
						: (*fLines)[_LineAt(fTrackingMouse->anchor)]->offset;
				fTrackingMouse->selEnd
					= (*fLines)[_LineAt(currentOffset) + 1]->offset;
			}
			break;

		case 2:
			// double click, extend selection wordwise
			if (currentOffset <= fTrackingMouse->anchor) {
				fTrackingMouse->selStart = _PreviousWordBoundary(currentOffset);
				fTrackingMouse->selEnd
					= fTrackingMouse->shiftDown
						? fSelEnd
						: _NextWordBoundary(fTrackingMouse->anchor);
			} else {
				fTrackingMouse->selStart
					= fTrackingMouse->shiftDown
						? fSelStart
						: _PreviousWordBoundary(fTrackingMouse->anchor);
				fTrackingMouse->selEnd = _NextWordBoundary(currentOffset);
			}
			break;

		default:
			// new click, extend selection char by char
			if (currentOffset <= fTrackingMouse->anchor) {
				fTrackingMouse->selStart = currentOffset;
				fTrackingMouse->selEnd
					= fTrackingMouse->shiftDown
						? fSelEnd : fTrackingMouse->anchor;
			} else {
				fTrackingMouse->selStart
					= fTrackingMouse->shiftDown
						? fSelStart : fTrackingMouse->anchor;
				fTrackingMouse->selEnd = currentOffset;
			}
			break;
	}

	// position caret to follow the direction of the selection
	if (fTrackingMouse->selEnd != fSelEnd)
		fCaretOffset = fTrackingMouse->selEnd;
	else if (fTrackingMouse->selStart != fSelStart)
		fCaretOffset = fTrackingMouse->selStart;

	Select(fTrackingMouse->selStart, fTrackingMouse->selEnd);
	_TrackMouse(where, NULL);

	return true;
}


// Tracks the mouse position, doing special actions like changing the
// view cursor.
// where The point where the mouse has moved.
// message The dragging message, if there is any.
// force Passed as second parameter of SetViewCursor()
void
BTextView::_TrackMouse(BPoint where, const BMessage* message, bool force)
{
	BRegion textRegion;
	GetTextRegion(fSelStart, fSelEnd, &textRegion);

	if (message && AcceptsDrop(message))
		_TrackDrag(where);
	else if ((fSelectable || fEditable)
		&& (fTrackingMouse != NULL || !textRegion.Contains(where))) {
		SetViewCursor(B_CURSOR_I_BEAM, force);
	} else
		SetViewCursor(B_CURSOR_SYSTEM_DEFAULT, force);
}


// Tracks the mouse position when the user is dragging some data.
void
BTextView::_TrackDrag(BPoint where)
{
	CALLED();
	if (Bounds().Contains(where))
		_DragCaret(OffsetAt(where));
}


// Method called to initiate a drag operation.
void
BTextView::_InitiateDrag()
{
	BMessage dragMessage(B_MIME_DATA);
	BBitmap* dragBitmap = NULL;
	BPoint bitmapPoint;
	BHandler* dragHandler = NULL;

	GetDragParameters(&dragMessage, &dragBitmap, &bitmapPoint, &dragHandler);
	SetViewCursor(B_CURSOR_SYSTEM_DEFAULT);

	if (dragBitmap != NULL)
		DragMessage(&dragMessage, dragBitmap, bitmapPoint, dragHandler);
	else {
		BRegion region;
		GetTextRegion(fSelStart, fSelEnd, &region);
		BRect bounds = Bounds();
		BRect dragRect = region.Frame();
		if (!bounds.Contains(dragRect))
			dragRect = bounds & dragRect;

		DragMessage(&dragMessage, dragRect, dragHandler);
	}

	BMessenger messenger(this);
	BMessage message(_DISPOSE_DRAG_);
	fDragRunner = new (nothrow) BMessageRunner(messenger, &message, 100000);
}


// Handles when some data is dropped on the view.
bool
BTextView::_MessageDropped(BMessage* message, BPoint where, BPoint offset)
{
	ASSERT(message);

	void* from = NULL;
	bool internalDrop = false;
	if (message->FindPointer("be:originator", &from) == B_OK
			&& from == this && fSelEnd != fSelStart)
		internalDrop = true;

	_DragCaret(-1);

	delete fDragRunner;
	fDragRunner = NULL;

	_TrackMouse(where, NULL);

	// are we sure we like this message?
	if (!AcceptsDrop(message))
		return false;

	int32 dropOffset = OffsetAt(where);
	if (dropOffset > TextLength())
		dropOffset = TextLength();

	// if this view initiated the drag, move instead of copy
	if (internalDrop) {
		// dropping onto itself?
		if (dropOffset >= fSelStart && dropOffset <= fSelEnd)
			return true;
	}

	ssize_t dataLength = 0;
	const char* text = NULL;
	entry_ref ref;
	if (message->FindData("text/plain", B_MIME_TYPE, (const void**)&text,
			&dataLength) == B_OK) {
		text_run_array* runArray = NULL;
		ssize_t runLength = 0;
		if (fStylable) {
			message->FindData("application/x-vnd.Be-text_run_array",
				B_MIME_TYPE, (const void**)&runArray, &runLength);
		}

		_FilterDisallowedChars((char*)text, dataLength, runArray);

		if (dataLength < 1) {
			beep();
			return true;
		}

		if (fUndo) {
			delete fUndo;
			fUndo = new DropUndoBuffer(this, text, dataLength, runArray,
				runLength, dropOffset, internalDrop);
		}

		if (internalDrop) {
			if (dropOffset > fSelEnd)
				dropOffset -= dataLength;
			Delete();
		}

		Insert(dropOffset, text, dataLength, runArray);
	}

	return true;
}


void
BTextView::_PerformAutoScrolling()
{
	// Scroll the view a bit if mouse is outside the view bounds
	BRect bounds = Bounds();
	BPoint scrollBy(B_ORIGIN);

	// R5 does a pretty soft auto-scroll, we try to do the same by
	// simply scrolling the distance between cursor and border
	if (fWhere.x > bounds.right) {
		scrollBy.x = fWhere.x - bounds.right;
	} else if (fWhere.x < bounds.left) {
		scrollBy.x = fWhere.x - bounds.left; // negative value
	}

	// prevent from scrolling out of view
	if (scrollBy.x != 0.0) {
		float rightMax = floorf(fTextRect.right + fLayoutData->rightInset);
		if (bounds.right + scrollBy.x > rightMax)
			scrollBy.x = rightMax - bounds.right;
		if (bounds.left + scrollBy.x < 0)
			scrollBy.x = -bounds.left;
	}

	if (CountLines() > 1) {
		// scroll in Y only if multiple lines!
		if (fWhere.y > bounds.bottom) {
			scrollBy.y = fWhere.y - bounds.bottom;
		} else if (fWhere.y < bounds.top) {
			scrollBy.y = fWhere.y - bounds.top; // negative value
		}

		// prevent from scrolling out of view
		if (scrollBy.y != 0.0) {
			float bottomMax = floorf(fTextRect.bottom
				+ fLayoutData->bottomInset);
			if (bounds.bottom + scrollBy.y > bottomMax)
				scrollBy.y = bottomMax - bounds.bottom;
			if (bounds.top + scrollBy.y < 0)
				scrollBy.y = -bounds.top;
		}
	}

	if (scrollBy != B_ORIGIN)
		ScrollBy(scrollBy.x, scrollBy.y);
}


// Updates the scrollbars associated with the object (if any).
void
BTextView::_UpdateScrollbars()
{
	BRect bounds(Bounds());
	BScrollBar* horizontalScrollBar = ScrollBar(B_HORIZONTAL);
 	BScrollBar* verticalScrollBar = ScrollBar(B_VERTICAL);

	// do we have a horizontal scroll bar?
	if (horizontalScrollBar != NULL) {
		long viewWidth = bounds.IntegerWidth();
		long dataWidth = (long)ceilf(fTextRect.IntegerWidth()
			+ fLayoutData->leftInset + fLayoutData->rightInset);

		long maxRange = dataWidth - viewWidth;
		maxRange = max_c(maxRange, 0);

		horizontalScrollBar->SetRange(0, (float)maxRange);
		horizontalScrollBar->SetProportion((float)viewWidth / (float)dataWidth);
		horizontalScrollBar->SetSteps(kHorizontalScrollBarStep, dataWidth / 10);
	}

	// how about a vertical scroll bar?
	if (verticalScrollBar != NULL) {
		long viewHeight = bounds.IntegerHeight();
		long dataHeight = (long)ceilf(fTextRect.IntegerHeight()
			+ fLayoutData->topInset + fLayoutData->bottomInset);

		long maxRange = dataHeight - viewHeight;
		maxRange = max_c(maxRange, 0);

		verticalScrollBar->SetRange(0, maxRange);
		verticalScrollBar->SetProportion((float)viewHeight / (float)dataHeight);
		verticalScrollBar->SetSteps(kVerticalScrollBarStep, viewHeight);
	}
}


// Scrolls by the given offsets
void
BTextView::_ScrollBy(float horizontal, float vertical)
{
	BRect bounds = Bounds();
	_ScrollTo(bounds.left + horizontal, bounds.top + vertical);
}


// Scrolls to the given position, making sure not to scroll out of bounds.
void
BTextView::_ScrollTo(float x, float y)
{
	BRect bounds = Bounds();
	long viewWidth = bounds.IntegerWidth();
	long viewHeight = bounds.IntegerHeight();

	if (x > fTextRect.right - viewWidth)
		x = fTextRect.right - viewWidth;
	if (x < 0.0)
		x = 0.0;

	if (y > fTextRect.bottom + fLayoutData->bottomInset - viewHeight)
		y = fTextRect.bottom + fLayoutData->bottomInset - viewHeight;
	if (y < 0.0)
		y = 0.0;

	ScrollTo(x, y);
}


// Autoresizes the view to fit the contained text.
void
BTextView::_AutoResize(bool redraw)
{
	if (!fResizable)
		return;

	BRect bounds = Bounds();
	float oldWidth = bounds.Width();
	float newWidth = ceilf(fLayoutData->leftInset + fTextRect.Width()
		+ fLayoutData->rightInset);

	if (fContainerView != NULL) {
		// NOTE: This container view thing is only used by Tracker.
		// move container view if not left aligned
		if (fAlignment == B_ALIGN_CENTER) {
			if (fmod(ceilf(newWidth - oldWidth), 2.0) != 0.0)
				newWidth += 1;
			fContainerView->MoveBy(ceilf(oldWidth - newWidth) / 2, 0);
		} else if (fAlignment == B_ALIGN_RIGHT) {
			fContainerView->MoveBy(ceilf(oldWidth - newWidth), 0);
		}
		// resize container view
		fContainerView->ResizeBy(ceilf(newWidth - oldWidth), 0);
	}


	if (redraw)
		_RequestDrawLines(0, 0);

	// erase any potential left over outside the text rect
	// (can only be on right hand side)
	BRect dirty(fTextRect.right + 1, fTextRect.top, bounds.right,
		fTextRect.bottom);
	if (dirty.IsValid()) {
		SetLowColor(ViewColor());
		FillRect(dirty, B_SOLID_LOW);
	}
}


// Creates a new offscreen BBitmap with an associated BView.
void
BTextView::_NewOffscreen(float padding)
{
	if (fOffscreen != NULL)
		_DeleteOffscreen();

#if USE_DOUBLEBUFFERING
	BRect bitmapRect(0, 0, fTextRect.Width() + padding, fTextRect.Height());
	fOffscreen = new BBitmap(bitmapRect, fColorSpace, true, false);
	if (fOffscreen != NULL && fOffscreen->Lock()) {
		BView* bufferView = new BView(bitmapRect, "drawing view", 0, 0);
		fOffscreen->AddChild(bufferView);
		fOffscreen->Unlock();
	}
#endif
}


// Deletes the textview's offscreen bitmap, if any.
void
BTextView::_DeleteOffscreen()
{
	if (fOffscreen != NULL && fOffscreen->Lock()) {
		delete fOffscreen;
		fOffscreen = NULL;
	}
}


// Creates a new offscreen bitmap, highlight the selection, and set the
// cursor to B_CURSOR_I_BEAM.
void
BTextView::_Activate()
{
	fActive = true;

	// Create a new offscreen BBitmap
	_NewOffscreen();

	if (fSelStart != fSelEnd) {
		if (fSelectable)
			Highlight(fSelStart, fSelEnd);
	} else
		_ShowCaret();

	BPoint where;
	uint32 buttons;
	GetMouse(&where, &buttons, false);
	if (Bounds().Contains(where))
		_TrackMouse(where, NULL);

	if (Window() != NULL) {
		BMessage* message;

		if (!Window()->HasShortcut(B_LEFT_ARROW, B_COMMAND_KEY)
			&& !Window()->HasShortcut(B_RIGHT_ARROW, B_COMMAND_KEY)) {
			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_LEFT_ARROW);
			message->AddInt32("modifiers", B_COMMAND_KEY);
			Window()->AddShortcut(B_LEFT_ARROW, B_COMMAND_KEY, message, this);

			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_RIGHT_ARROW);
			message->AddInt32("modifiers", B_COMMAND_KEY);
			Window()->AddShortcut(B_RIGHT_ARROW, B_COMMAND_KEY, message, this);

			fInstalledNavigateCommandWordwiseShortcuts = true;
		}
		if (!Window()->HasShortcut(B_LEFT_ARROW, B_COMMAND_KEY | B_SHIFT_KEY)
			&& !Window()->HasShortcut(B_RIGHT_ARROW,
				B_COMMAND_KEY | B_SHIFT_KEY)) {
			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_LEFT_ARROW);
			message->AddInt32("modifiers", B_COMMAND_KEY | B_SHIFT_KEY);
			Window()->AddShortcut(B_LEFT_ARROW, B_COMMAND_KEY | B_SHIFT_KEY,
				message, this);

			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_RIGHT_ARROW);
			message->AddInt32("modifiers", B_COMMAND_KEY | B_SHIFT_KEY);
			Window()->AddShortcut(B_RIGHT_ARROW, B_COMMAND_KEY | B_SHIFT_KEY,
				message, this);

			fInstalledSelectCommandWordwiseShortcuts = true;
		}

		if (!Window()->HasShortcut(B_LEFT_ARROW, B_OPTION_KEY)
			&& !Window()->HasShortcut(B_RIGHT_ARROW, B_OPTION_KEY)) {
			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_LEFT_ARROW);
			message->AddInt32("modifiers", B_OPTION_KEY);
			Window()->AddShortcut(B_LEFT_ARROW, B_OPTION_KEY, message, this);

			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_RIGHT_ARROW);
			message->AddInt32("modifiers", B_OPTION_KEY);
			Window()->AddShortcut(B_RIGHT_ARROW, B_OPTION_KEY, message, this);

			fInstalledNavigateOptionWordwiseShortcuts = true;
		}
		if (!Window()->HasShortcut(B_LEFT_ARROW, B_OPTION_KEY | B_SHIFT_KEY)
			&& !Window()->HasShortcut(B_RIGHT_ARROW,
				B_OPTION_KEY | B_SHIFT_KEY)) {
			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_LEFT_ARROW);
			message->AddInt32("modifiers", B_OPTION_KEY | B_SHIFT_KEY);
			Window()->AddShortcut(B_LEFT_ARROW, B_OPTION_KEY | B_SHIFT_KEY,
				message, this);

			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_RIGHT_ARROW);
			message->AddInt32("modifiers", B_OPTION_KEY | B_SHIFT_KEY);
			Window()->AddShortcut(B_RIGHT_ARROW, B_OPTION_KEY | B_SHIFT_KEY,
				message, this);

			fInstalledSelectOptionWordwiseShortcuts = true;
		}

		if (!Window()->HasShortcut(B_UP_ARROW, B_OPTION_KEY)
			&& !Window()->HasShortcut(B_DOWN_ARROW, B_OPTION_KEY)) {
			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_UP_ARROW);
			message->AddInt32("modifiers", B_OPTION_KEY);
			Window()->AddShortcut(B_UP_ARROW, B_OPTION_KEY, message, this);

			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_DOWN_ARROW);
			message->AddInt32("modifiers", B_OPTION_KEY);
			Window()->AddShortcut(B_DOWN_ARROW, B_OPTION_KEY, message, this);

			fInstalledNavigateOptionLinewiseShortcuts = true;
		}
		if (!Window()->HasShortcut(B_UP_ARROW, B_OPTION_KEY | B_SHIFT_KEY)
			&& !Window()->HasShortcut(B_DOWN_ARROW,
				B_OPTION_KEY | B_SHIFT_KEY)) {
			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_UP_ARROW);
			message->AddInt32("modifiers", B_OPTION_KEY | B_SHIFT_KEY);
			Window()->AddShortcut(B_UP_ARROW, B_OPTION_KEY | B_SHIFT_KEY,
				message, this);

			message = new BMessage(kMsgNavigateArrow);
			message->AddInt32("key", B_DOWN_ARROW);
			message->AddInt32("modifiers", B_OPTION_KEY | B_SHIFT_KEY);
			Window()->AddShortcut(B_DOWN_ARROW, B_OPTION_KEY | B_SHIFT_KEY,
				message, this);

			fInstalledSelectOptionLinewiseShortcuts = true;
		}

		if (!Window()->HasShortcut(B_HOME, B_COMMAND_KEY)
			&& !Window()->HasShortcut(B_END, B_COMMAND_KEY)) {
			message = new BMessage(kMsgNavigatePage);
			message->AddInt32("key", B_HOME);
			message->AddInt32("modifiers", B_COMMAND_KEY);
			Window()->AddShortcut(B_HOME, B_COMMAND_KEY, message, this);

			message = new BMessage(kMsgNavigatePage);
			message->AddInt32("key", B_END);
			message->AddInt32("modifiers", B_COMMAND_KEY);
			Window()->AddShortcut(B_END, B_COMMAND_KEY, message, this);

			fInstalledNavigateHomeEndDocwiseShortcuts = true;
		}
		if (!Window()->HasShortcut(B_HOME, B_COMMAND_KEY | B_SHIFT_KEY)
			&& !Window()->HasShortcut(B_END, B_COMMAND_KEY | B_SHIFT_KEY)) {
			message = new BMessage(kMsgNavigatePage);
			message->AddInt32("key", B_HOME);
			message->AddInt32("modifiers", B_COMMAND_KEY | B_SHIFT_KEY);
			Window()->AddShortcut(B_HOME, B_COMMAND_KEY | B_SHIFT_KEY,
				message, this);

			message = new BMessage(kMsgNavigatePage);
			message->AddInt32("key", B_END);
			message->AddInt32("modifiers", B_COMMAND_KEY | B_SHIFT_KEY);
			Window()->AddShortcut(B_END, B_COMMAND_KEY | B_SHIFT_KEY,
				message, this);

			fInstalledSelectHomeEndDocwiseShortcuts = true;
		}
	}
}


// Unhilights the selection, set the cursor to B_CURSOR_SYSTEM_DEFAULT.
void
BTextView::_Deactivate()
{
	fActive = false;

	_CancelInputMethod();
	_DeleteOffscreen();

	if (fSelStart != fSelEnd) {
		if (fSelectable)
			Highlight(fSelStart, fSelEnd);
	} else
		_HideCaret();

	if (Window() != NULL) {
		if (fInstalledNavigateCommandWordwiseShortcuts) {
			Window()->RemoveShortcut(B_LEFT_ARROW, B_COMMAND_KEY);
			Window()->RemoveShortcut(B_RIGHT_ARROW, B_COMMAND_KEY);
			fInstalledNavigateCommandWordwiseShortcuts = false;
		}
		if (fInstalledSelectCommandWordwiseShortcuts) {
			Window()->RemoveShortcut(B_LEFT_ARROW, B_COMMAND_KEY | B_SHIFT_KEY);
			Window()->RemoveShortcut(B_RIGHT_ARROW,
				B_COMMAND_KEY | B_SHIFT_KEY);
			fInstalledSelectCommandWordwiseShortcuts = false;
		}

		if (fInstalledNavigateOptionWordwiseShortcuts) {
			Window()->RemoveShortcut(B_LEFT_ARROW, B_OPTION_KEY);
			Window()->RemoveShortcut(B_RIGHT_ARROW, B_OPTION_KEY);
			fInstalledNavigateOptionWordwiseShortcuts = false;
		}
		if (fInstalledSelectOptionWordwiseShortcuts) {
			Window()->RemoveShortcut(B_LEFT_ARROW, B_OPTION_KEY | B_SHIFT_KEY);
			Window()->RemoveShortcut(B_RIGHT_ARROW, B_OPTION_KEY | B_SHIFT_KEY);
			fInstalledSelectOptionWordwiseShortcuts = false;
		}

		if (fInstalledNavigateOptionLinewiseShortcuts) {
			Window()->RemoveShortcut(B_UP_ARROW, B_OPTION_KEY);
			Window()->RemoveShortcut(B_DOWN_ARROW, B_OPTION_KEY);
			fInstalledNavigateOptionLinewiseShortcuts = false;
		}
		if (fInstalledSelectOptionLinewiseShortcuts) {
			Window()->RemoveShortcut(B_UP_ARROW, B_OPTION_KEY | B_SHIFT_KEY);
			Window()->RemoveShortcut(B_DOWN_ARROW, B_OPTION_KEY | B_SHIFT_KEY);
			fInstalledSelectOptionLinewiseShortcuts = false;
		}

		if (fInstalledNavigateHomeEndDocwiseShortcuts) {
			Window()->RemoveShortcut(B_HOME, B_COMMAND_KEY);
			Window()->RemoveShortcut(B_END, B_COMMAND_KEY);
			fInstalledNavigateHomeEndDocwiseShortcuts = false;
		}
		if (fInstalledSelectHomeEndDocwiseShortcuts) {
			Window()->RemoveShortcut(B_HOME, B_COMMAND_KEY | B_SHIFT_KEY);
			Window()->RemoveShortcut(B_END, B_COMMAND_KEY | B_SHIFT_KEY);
			fInstalledSelectHomeEndDocwiseShortcuts = false;
		}
	}
}


// Changes the passed font to be displayable by the object.
// Set font rotation to 0, removes any font flag, set font spacing
// to B_BITMAP_SPACING and font encoding to B_UNICODE_UTF8
void
BTextView::_NormalizeFont(BFont* font)
{
	if (font) {
		font->SetRotation(0.0f);
		font->SetFlags(0);
		font->SetSpacing(B_BITMAP_SPACING);
		font->SetEncoding(B_UNICODE_UTF8);
	}
}


void
BTextView::_SetRunArray(int32 startOffset, int32 endOffset,
	const text_run_array* runs)
{
	const int32 numStyles = runs->count;
	if (numStyles > 0) {
		const text_run* theRun = &runs->runs[0];
		for (int32 index = 0; index < numStyles; index++) {
			int32 fromOffset = theRun->offset + startOffset;
			int32 toOffset = endOffset;
			if (index + 1 < numStyles) {
				toOffset = (theRun + 1)->offset + startOffset;
				toOffset = (toOffset > endOffset) ? endOffset : toOffset;
			}

			_ApplyStyleRange(fromOffset, toOffset, B_FONT_ALL, &theRun->font,
				&theRun->color, false);

			theRun++;
		}
		fStyles->InvalidateNullStyle();
	}
}


// Returns the character class of the character at the given offset.
// offset The offset where the wanted character can be found.
// return A value which represents the character's classification.
uint32
BTextView::_CharClassification(int32 offset) const
{
	// TODO: Should check against a list of characters containing also
	// japanese word breakers.
	// And what about other languages ? Isn't there a better way to check
	// for separator characters ?
	// Andrew suggested to have a look at UnicodeBlockObject.h
	switch (fText->RealCharAt(offset)) {
		case '\0':
			return CHAR_CLASS_END_OF_TEXT;

		case B_SPACE:
		case B_TAB:
		case B_ENTER:
			return CHAR_CLASS_WHITESPACE;

		case '=':
		case '+':
		case '@':
		case '#':
		case '$':
		case '%':
		case '^':
		case '&':
		case '*':
		case '\\':
		case '|':
		case '<':
		case '>':
		case '/':
		case '~':
			return CHAR_CLASS_GRAPHICAL;

		case '\'':
		case '"':
			return CHAR_CLASS_QUOTE;

		case ',':
		case '.':
		case '?':
		case '!':
		case ';':
		case ':':
		case '-':
			return CHAR_CLASS_PUNCTUATION;

		case '(':
		case '[':
		case '{':
			return CHAR_CLASS_PARENS_OPEN;

		case ')':
		case ']':
		case '}':
			return CHAR_CLASS_PARENS_CLOSE;

		default:
			return CHAR_CLASS_DEFAULT;
	}
}


// Returns the offset of the next UTF8 character within the BTextView's text.
// offset The offset where to start looking.
// return The offset of the next UTF8 character.
int32
BTextView::_NextInitialByte(int32 offset) const
{
	if (offset >= fText->Length())
		return offset;

	for (++offset; (ByteAt(offset) & 0xC0) == 0x80; ++offset)
		;

	return offset;
}


// Returns the offset of the previous UTF8 character within the BTextView's
// text.
// offset The offset where to start looking.
// return The offset of the previous UTF8 character.
int32
BTextView::_PreviousInitialByte(int32 offset) const
{
	if (offset <= 0)
		return 0;

	int32 count = 6;

	for (--offset; offset > 0 && count; --offset, --count) {
		if ((ByteAt(offset) & 0xC0) != 0x80)
			break;
	}

	return count ? offset : 0;
}


bool
BTextView::_GetProperty(BMessage* specifier, int32 form, const char* property,
	BMessage* reply)
{
	CALLED();
	if (strcmp(property, "selection") == 0) {
		reply->what = B_REPLY;
		reply->AddInt32("result", fSelStart);
		reply->AddInt32("result", fSelEnd);
		reply->AddInt32("error", B_OK);

		return true;
	} else if (strcmp(property, "Text") == 0) {
		if (IsTypingHidden()) {
			// Do not allow stealing passwords via scripting
			beep();
			return false;
		}

		int32 index, range;
		specifier->FindInt32("index", &index);
		specifier->FindInt32("range", &range);

		char* buffer = new char[range + 1];
		GetText(index, range, buffer);

		reply->what = B_REPLY;
		reply->AddString("result", buffer);
		reply->AddInt32("error", B_OK);

		delete[] buffer;

		return true;
	} else if (strcmp(property, "text_run_array") == 0)
		return false;

	return false;
}


bool
BTextView::_SetProperty(BMessage* specifier, int32 form, const char* property,
	BMessage* reply)
{
	CALLED();
	if (strcmp(property, "selection") == 0) {
		int32 index, range;

		specifier->FindInt32("index", &index);
		specifier->FindInt32("range", &range);

		Select(index, index + range);

		reply->what = B_REPLY;
		reply->AddInt32("error", B_OK);

		return true;
	} else if (strcmp(property, "Text") == 0) {
		int32 index, range;
		specifier->FindInt32("index", &index);
		specifier->FindInt32("range", &range);

		const char* buffer = NULL;
		if (specifier->FindString("data", &buffer) == B_OK)
			InsertText(buffer, range, index, NULL);
		else
			DeleteText(index, range);

		reply->what = B_REPLY;
		reply->AddInt32("error", B_OK);

		return true;
	} else if (strcmp(property, "text_run_array") == 0)
		return false;

	return false;
}


bool
BTextView::_CountProperties(BMessage* specifier, int32 form,
	const char* property, BMessage* reply)
{
	CALLED();
	if (strcmp(property, "Text") == 0) {
		reply->what = B_REPLY;
		reply->AddInt32("result", TextLength());
		reply->AddInt32("error", B_OK);
		return true;
	}

	return false;
}


// Called when the object receives a B_INPUT_METHOD_CHANGED message.
void
BTextView::_HandleInputMethodChanged(BMessage* message)
{
	// TODO: block input if not editable (Andrew)
	ASSERT(fInline != NULL);

	const char* string = NULL;
	if (message->FindString("be:string", &string) < B_OK || string == NULL)
		return;

	_HideCaret();

	if (IsFocus())
		be_app->ObscureCursor();

	// If we find the "be:confirmed" boolean (and the boolean is true),
	// it means it's over for now, so the current InlineInput object
	// should become inactive. We will probably receive a
	// B_INPUT_METHOD_STOPPED message after this one.
	bool confirmed;
	if (message->FindBool("be:confirmed", &confirmed) != B_OK)
		confirmed = false;

	// Delete the previously inserted text (if any)
	if (fInline->IsActive()) {
		const int32 oldOffset = fInline->Offset();
		DeleteText(oldOffset, oldOffset + fInline->Length());
		if (confirmed)
			fInline->SetActive(false);
		fCaretOffset = fSelStart = fSelEnd = oldOffset;
	}

	const int32 stringLen = strlen(string);

	fInline->SetOffset(fSelStart);
	fInline->SetLength(stringLen);
	fInline->ResetClauses();

	if (!confirmed && !fInline->IsActive())
		fInline->SetActive(true);

	// Get the clauses, and pass them to the InlineInput object
	// TODO: Find out if what we did it's ok, currently we don't consider
	// clauses at all, while the bebook says we should; though the visual
	// effect we obtained seems correct. Weird.
	int32 clauseCount = 0;
	int32 clauseStart;
	int32 clauseEnd;
	while (message->FindInt32("be:clause_start", clauseCount, &clauseStart)
			== B_OK
		&& message->FindInt32("be:clause_end", clauseCount, &clauseEnd)
			== B_OK) {
		if (!fInline->AddClause(clauseStart, clauseEnd))
			break;
		clauseCount++;
	}

	if (confirmed) {
		_Refresh(fSelStart, fSelEnd, true);
		_ShowCaret();

		// now we need to feed ourselves the individual characters as if the
		// user would have pressed them now - this lets KeyDown() pick out all
		// the special characters like B_BACKSPACE, cursor keys and the like:
		const char* currPos = string;
		const char* prevPos = currPos;
		while (*currPos != '\0') {
			if ((*currPos & 0xC0) == 0xC0) {
				// found the start of an UTF-8 char, we collect while it lasts
				++currPos;
				while ((*currPos & 0xC0) == 0x80)
					++currPos;
			} else if ((*currPos & 0xC0) == 0x80) {
				// illegal: character starts with utf-8 intermediate byte,
				// skip it
				prevPos = ++currPos;
			} else {
				// single byte character/code, just feed that
				++currPos;
			}
			KeyDown(prevPos, currPos - prevPos);
			prevPos = currPos;
		}

		_Refresh(fSelStart, fSelEnd, true);
	} else {
		// temporarily show transient state of inline input
		int32 selectionStart = 0;
		int32 selectionEnd = 0;
		message->FindInt32("be:selection", 0, &selectionStart);
		message->FindInt32("be:selection", 1, &selectionEnd);

		fInline->SetSelectionOffset(selectionStart);
		fInline->SetSelectionLength(selectionEnd - selectionStart);

		const int32 inlineOffset = fInline->Offset();
		InsertText(string, stringLen, fSelStart, NULL);

		_Refresh(inlineOffset, fSelEnd, true);
		_ShowCaret();
	}

}


// Called when the object receives a B_INPUT_METHOD_LOCATION_REQUEST message.
void
BTextView::_HandleInputMethodLocationRequest()
{
	ASSERT(fInline != NULL);

	int32 offset = fInline->Offset();
	const int32 limit = offset + fInline->Length();

	BMessage message(B_INPUT_METHOD_EVENT);
	message.AddInt32("be:opcode", B_INPUT_METHOD_LOCATION_REQUEST);

	// Add the location of the UTF8 characters
	while (offset < limit) {
		float height;
		BPoint where = PointAt(offset, &height);
		ConvertToScreen(&where);

		message.AddPoint("be:location_reply", where);
		message.AddFloat("be:height_reply", height);

		offset = _NextInitialByte(offset);
	}

	fInline->Method()->SendMessage(&message);
}


// Tells the input server method addon to stop the current transaction.
void
BTextView::_CancelInputMethod()
{
	if (!fInline)
		return;

	InlineInput* inlineInput = fInline;
	fInline = NULL;

	if (inlineInput->IsActive() && Window()) {
		_Refresh(inlineInput->Offset(), fText->Length() - inlineInput->Offset(),
			false);

		BMessage message(B_INPUT_METHOD_EVENT);
		message.AddInt32("be:opcode", B_INPUT_METHOD_STOPPED);
		inlineInput->Method()->SendMessage(&message);
	}

	delete inlineInput;
}


// Returns the line number for the character at the given offset.
//	N.B.: this will never return the last line (use LineAt() if you
//	need to be correct about that)
// offset The offset of the wanted character.
// return A line number.
int32
BTextView::_LineAt(int32 offset) const
{
	return fLines->OffsetToLine(offset);
}


// Returns the line number for the given point.
//	N.B.: this will never return the last line (use LineAt() if you
//	need to be correct about that)
// point A point.
// return A line number.
int32
BTextView::_LineAt(const BPoint& point) const
{
	return fLines->PixelToLine(point.y - fTextRect.top);
}


// Returns whether or not the given offset is on the empty line at the end of
// the buffer.
bool
BTextView::_IsOnEmptyLastLine(int32 offset) const
{
	return (offset == TextLength() && offset > 0
		&& fText->RealCharAt(offset - 1) == B_ENTER);
}


void
BTextView::_ApplyStyleRange(int32 fromOffset, int32 toOffset, uint32 mode,
	const BFont* font, const rgb_color* color, bool syncNullStyle)
{
	if (font != NULL) {
		// if a font has been given, normalize it
		BFont normalized = *font;
		_NormalizeFont(&normalized);
		font = &normalized;
	}

	if (!fStylable) {
		// always apply font and color to full range for non-stylable textviews
		fromOffset = 0;
		toOffset = fText->Length();
	}

	if (syncNullStyle)
		fStyles->SyncNullStyle(fromOffset);

	fStyles->SetStyleRange(fromOffset, toOffset, fText->Length(), mode,
		font, color);
}


float
BTextView::_NullStyleHeight() const
{
	const BFont* font = NULL;
	fStyles->GetNullStyle(&font, NULL);

	font_height fontHeight;
	font->GetHeight(&fontHeight);
	return ceilf(fontHeight.ascent + fontHeight.descent + 1);
}


void
BTextView::_ShowContextMenu(BPoint where)
{
	bool isRedo;
	undo_state state = UndoState(&isRedo);
	bool isUndo = state != B_UNDO_UNAVAILABLE && !isRedo;

	int32 start;
	int32 finish;
	GetSelection(&start, &finish);

	bool canEdit = IsEditable();
	int32 length = TextLength();

	BPopUpMenu* menu = new BPopUpMenu(B_EMPTY_STRING, false, false);

	BLayoutBuilder::Menu<>(menu)
		.AddItem(TRANSLATE("Undo"), B_UNDO/*, 'Z'*/)
			.SetEnabled(canEdit && isUndo)
		.AddItem(TRANSLATE("Redo"), B_UNDO/*, 'Z', B_SHIFT_KEY*/)
			.SetEnabled(canEdit && isRedo)
		.AddSeparator()
		.AddItem(TRANSLATE("Cut"), B_CUT, 'X')
			.SetEnabled(canEdit && start != finish)
		.AddItem(TRANSLATE("Copy"), B_COPY, 'C')
			.SetEnabled(start != finish)
		.AddItem(TRANSLATE("Paste"), B_PASTE, 'V')
			.SetEnabled(canEdit && be_clipboard->SystemCount() > 0)
		.AddSeparator()
		.AddItem(TRANSLATE("Select All"), B_SELECT_ALL, 'A')
			.SetEnabled(!(start == 0 && finish == length))
	;

	menu->SetTargetForItems(this);
	ConvertToScreen(&where);
	menu->Go(where, true, true,	true);
}


void
BTextView::_FilterDisallowedChars(char* text, ssize_t& length,
	text_run_array* runArray)
{
	if (!fDisallowedChars)
		return;

	if (fDisallowedChars->IsEmpty() || !text)
		return;

	ssize_t stringIndex = 0;
	if (runArray) {
		ssize_t remNext = 0;

		for (int i = 0; i < runArray->count; i++) {
			runArray->runs[i].offset -= remNext;
			while (stringIndex < runArray->runs[i].offset
				&& stringIndex < length) {
				if (fDisallowedChars->HasItem(
					reinterpret_cast<void*>(text[stringIndex]))) {
					memmove(text + stringIndex, text + stringIndex + 1,
						length - stringIndex - 1);
					length--;
					runArray->runs[i].offset--;
					remNext++;
				} else
					stringIndex++;
			}
		}
	}

	while (stringIndex < length) {
		if (fDisallowedChars->HasItem(
			reinterpret_cast<void*>(text[stringIndex]))) {
			memmove(text + stringIndex, text + stringIndex + 1,
				length - stringIndex - 1);
			length--;
		} else
			stringIndex++;
	}
}


// #pragma mark - BTextView::TextTrackState


BTextView::TextTrackState::TextTrackState(BMessenger messenger)
	:
	clickOffset(0),
	shiftDown(false),
	anchor(0),
	selStart(0),
	selEnd(0),
	fRunner(NULL)
{
	BMessage message(_PING_);
	const bigtime_t scrollSpeed = 25 * 1000;	// 40 scroll steps per second
	fRunner = new (nothrow) BMessageRunner(messenger, &message, scrollSpeed);
}


BTextView::TextTrackState::~TextTrackState()
{
	delete fRunner;
}


void
BTextView::TextTrackState::SimulateMouseMovement(BTextView* textView)
{
	BPoint where;
	uint32 buttons;
	// When the mouse cursor is still and outside the textview,
	// no B_MOUSE_MOVED message are sent, obviously. But scrolling
	// has to work neverthless, so we "fake" a MouseMoved() call here.
	textView->GetMouse(&where, &buttons);
	textView->_PerformMouseMoved(where, B_INSIDE_VIEW);
}


extern "C" void
B_IF_GCC_2(InvalidateLayout__9BTextViewb,  _ZN9BTextView16InvalidateLayoutEb)(
	BTextView* view, bool descendants)
{
	perform_data_layout_invalidated data;
	data.descendants = descendants;

	view->Perform(PERFORM_CODE_LAYOUT_INVALIDATED, &data);
}