xref: /haiku/src/kits/interface/TextView.cpp (revision d9cebac2b77547b7064f22497514eecd2d047160)

/*
 * Copyright 2001-2007, Haiku Inc.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *		Hiroshi Lockheimer (BTextView is based on his STEEngine)
 *		Marc Flerackers (mflerackers@androme.be)
 *		Stefano Ceccherini (burton666@libero.it)
 */

/**	BTextView displays and manages styled text. */

// TODOs:
// - Finish documenting this class
// - 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>
using namespace std;

#include <Application.h>
#include <Beep.h>
#include <Bitmap.h>
#include <Clipboard.h>
#include <Debug.h>
#include <Input.h>
#include <MessageRunner.h>
#include <PropertyInfo.h>
#include <Region.h>
#include <ScrollBar.h>
#include <TextView.h>
#include <Window.h>

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


//#define TRACE_TEXTVIEW
#ifdef TRACE_TEXTVIEW
	#define CALLED() printf("%s\n", __PRETTY_FUNCTION__)
#else
	#define CALLED()
#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 {
	B_SEPARATOR_CHARACTER,
	B_OTHER_CHARACTER
};


class _BTextTrackState_ {
public:
	_BTextTrackState_(BMessenger messenger);
	~_BTextTrackState_();

	void SimulateMouseMovement(BTextView *view);

	int32 clickOffset;
	bool shiftDown;
	BRect selectionRect;

	int32 anchor;
	int32 selStart;
	int32 selEnd;

private:
	BMessageRunner *fRunner;
};


// Initialized/finalized by init/fini_interface_kit
_BWidthBuffer_* BTextView::sWidths = NULL;
sem_id BTextView::sWidthSem = B_BAD_SEM_ID;
int32 BTextView::sWidthAtom = 0;


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


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 }
};


/*! \brief Creates a BTextView object with the given attributes.
	\param frame The rect which will enclose the BTextView object.
	\param name The name of the object.
	\param textRect Determines the area of the text within the BTextView object.
	\param resizeMask The resizing mask for the BTextView, passed to the BView constructor.
	\param flags The flags for the BTextView, passed to the BView constructor.
*/
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);
}


/*! \brief Creates a BTextView object with the given attributes.
	\param frame The rect which will enclose the BTextView object.
	\param name The name of the object.
	\param textRect Determines the area of the text within the BTextView object.
	\param initialFont The BTextView will display its text using this font, unless otherwise specified.
	\param initialColor The BTextView will display its text using this color, unless otherwise specified.
	\param resizeMask The resizing mask for the BTextView, passed to the BView constructor.
	\param flags The flags for the BTextView, passed to the BView constructor.
*/
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);
}


/*! \brief Creates a BTextView object from the passed BMessage.
	\param archive The BMessage from which the object shall be created.
*/
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);
		}
	}

}


/*! \brief Frees the memory allocated and destroy the object created on construction.
*/
BTextView::~BTextView()
{
	CancelInputMethod();
	StopMouseTracking();
	DeleteOffscreen();

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


/*! \brief Static function used to istantiate a BTextView object from the given BMessage.
	\param archive The BMessage from which the object shall be created.
	\return A constructed BTextView as a BArchivable object.
*/
BArchivable *
BTextView::Instantiate(BMessage *archive)
{
	CALLED();
	if (validate_instantiation(archive, "BTextView"))
		return new BTextView(archive);
	return NULL;
}


/*! \brief Archives the object into the passed message.
	\param data A pointer to the message where to archive the object.
	\param deep ?
	\return \c B_OK if everything went well, an error code if not.
*/
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;
}


/*! \brief Hook function called when the BTextView is added to the
	window's view hierarchy.

	Set the window's pulse rate to 2 per second and adjust scrollbars if needed
*/
void
BTextView::AttachedToWindow()
{
	BView::AttachedToWindow();

	SetDrawingMode(B_OP_COPY);

	Window()->SetPulseRate(500000);

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

	if (fResizable)
		AutoResize(true);

	UpdateScrollbars();

	SetViewCursor(B_CURSOR_SYSTEM_DEFAULT);
}


/*! \brief Hook function called when the BTextView is removed from the
	window's view hierarchy.
*/
void
BTextView::DetachedFromWindow()
{
	BView::DetachedFromWindow();
}


/*! \brief Hook function called whenever
	the contents of the BTextView need to be (re)drawn.
	\param updateRect The rect which needs to be redrawn
*/
void
BTextView::Draw(BRect updateRect)
{
	// what lines need to be drawn?
	int32 startLine = LineAt(BPoint(0.0f, updateRect.top));
	int32 endLine = LineAt(BPoint(0.0f, updateRect.bottom));

	// TODO: DrawLines draw the text over and over, causing the text to
	// antialias against itself. In theory we should use an offscreen bitmap
	// to draw the text which would eliminate the problem.
	//DrawLines(startLine, endLine);
	Refresh(OffsetAt(startLine), OffsetAt(endLine + 1), false, false);
}


/*! \brief Hook function called when a mouse button is clicked while
	the cursor is in the view.
	\param where The location where the mouse button has been clicked.
*/
void
BTextView::MouseDown(BPoint where)
{
	// should we even bother?
	if (!fEditable && !fSelectable)
		return;

	CancelInputMethod();

	if (!IsFocus())
		MakeFocus();

	_HideCaret();

	StopMouseTracking();

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

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

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

	bigtime_t clickTime = system_time();
	bigtime_t clickSpeed = 0;
	get_click_speed(&clickSpeed);
	bool multipleClick = false;
	if (clickTime - fClickTime < clickSpeed && fClickOffset == fTrackingMouse->clickOffset)
		multipleClick = true;

	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();
			return;
		}
	}

	if (multipleClick) {
		if (fClickCount > 1) {
			fClickCount = 0;
			fClickTime = 0;
		} else {
			fClickCount = 2;
			fClickTime = clickTime;
		}
	} else {
		fClickOffset = fTrackingMouse->clickOffset;
		fClickCount = 1;
		fClickTime = clickTime;

		// Deselect any previously selected text
		if (!fTrackingMouse->shiftDown)
			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);
}


/*! \brief Hook function called when a mouse button is released while
	the cursor is in the view.
	\param where The point where the mouse button has been released.

	Stops asynchronous mouse tracking
*/
void
BTextView::MouseUp(BPoint where)
{
	BView::MouseUp(where);
	PerformMouseUp(where);

	delete fDragRunner;
	fDragRunner = NULL;
}


/*! \brief Hook function called whenever the mouse cursor enters, exits
	or moves inside the view.
	\param where The point where the mouse cursor has moved to.
	\param code A code which tells if the mouse entered or exited the view
	\param message The message containing dragged information, if any.
*/
void
BTextView::MouseMoved(BPoint where, uint32 code, const BMessage *message)
{
	// Check if it's a "click'n'move
	if (PerformMouseMoved(where, code))
		return;

	bool sync = false;
	switch (code) {
		// We force a sync when the mouse enters the view
		case B_ENTERED_VIEW:
			sync = true;
			// supposed to fall through
		case B_INSIDE_VIEW:
			TrackMouse(where, message, sync);
			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;
	}
}


/*! \brief Hook function called when the window becomes the active window
	or gives up that status.
	\param state If true, window has just become active, if false, window has
	just become inactive.
*/
void
BTextView::WindowActivated(bool state)
{
	BView::WindowActivated(state);

	if (state && IsFocus()) {
		if (!fActive)
			Activate();
	} else {
		if (fActive)
			Deactivate();
	}

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

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


/*! \brief Hook function called whenever 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
	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();
}


/*! \brief Hook function called every x microseconds.
	It's the function which makes the caret blink.
*/
void
BTextView::Pulse()
{
	if (fActive && fEditable && fSelStart == fSelEnd) {
		if (system_time() > (fCaretTime + 500000.0))
			InvertCaret();
	}
}


/*! \brief Hook function called when the view's frame is resized.
	\param width The new view's width.
	\param height The new view's height.

	Updates the associated scrollbars.
*/
void
BTextView::FrameResized(float width, float height)
{
	BView::FrameResized(width, height);
	UpdateScrollbars();
}


/*! \brief Highlight/unhighlight the selection when the view gets
		or looses the focus.
	\param focusState The focus state: true, if the view is getting the focus,
		false otherwise.
*/
void
BTextView::MakeFocus(bool focusState)
{
	BView::MakeFocus(focusState);

	if (focusState && Window() && Window()->IsActive()) {
		if (!fActive)
			Activate();
	} else {
		if (fActive)
			Deactivate();
	}
}


/*! \brief Hook function executed every time the BTextView gets a message.
	\param message The received 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 _BInlineInput_(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;

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


/*! \brief Returns the proper handler for the given scripting message.
	\param message The scripting message which needs to be examined.
	\param index The index of the specifier
	\param specifier The message which contains the specifier
	\param what The 'what' field of the specifier message.
	\param property The name of the targetted property
	\return The proper BHandler for the given scripting 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 d, void *arg)
{
	return BView::Perform(d, arg);
}


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


void
BTextView::SetText(const char *inText, int32 inLength, const text_run_array *inRuns)
{
	CancelInputMethod();

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

	// remove data from buffer
	if (fText->Length() > 0)
		DeleteText(0, fText->Length()); // TODO: was fText->Length() - 1

	if (inText != NULL && inLength > 0)
		InsertText(inText, inLength, 0, inRuns);

	// recalc line breaks and draw the text
	Refresh(0, inLength, true, false);
	fClickOffset = fSelStart = fSelEnd = 0;
	ScrollToOffset(fSelStart);

	// draw the caret
	if (fActive)
		_ShowCaret();
}


void
BTextView::SetText(BFile *inFile, int32 inOffset, int32 inLength,
						 const text_run_array *inRuns)
{
	CALLED();

	CancelInputMethod();

	if (!inFile)
		return;

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

	fText->InsertText(inFile, inOffset, inLength, 0);

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

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

	if (inRuns != NULL)
		SetRunArray(inOffset, inOffset + inLength, inRuns);
	else {
		// apply nullStyle to inserted text
		fStyles->SyncNullStyle(inOffset);
		fStyles->SetStyleRange(inOffset, inOffset + inLength,
							  fText->Length(), B_FONT_ALL, NULL, NULL);
	}

	// recalc line breaks and draw the text
	Refresh(0, inLength, true, false);
	fClickOffset = fSelStart = fSelEnd = 0;
	ScrollToOffset(fSelStart);

	// draw the caret
	if (fActive)
		_ShowCaret();
}


void
BTextView::Insert(const char *inText, const text_run_array *inRuns)
{
	if (inText != NULL)
		DoInsertText(inText, strlen(inText), fSelStart, inRuns, NULL);
}


void
BTextView::Insert(const char *inText, int32 inLength, const text_run_array *inRuns)
{
	if (inText != NULL && inLength > 0) {
		int32 realLength = strlen(inText);
		DoInsertText(inText, min_c(inLength, realLength), fSelStart, inRuns, NULL);
	}
}


void
BTextView::Insert(int32 startOffset, const char *inText, int32 inLength,
					   const text_run_array *inRuns)
{
	CALLED();

	// do we really need to do anything?
	if (inText != NULL && inLength > 0) {
		int32 realLength = strlen(inText);
		DoInsertText(inText, min_c(inLength, realLength), startOffset, inRuns, NULL);
	}
}


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


/*! \brief Delets the text comprised within the given offsets.
	\param startOffset The offset of the text to delete.
	\param endOffset The offset where the text to delete ends.
*/
void
BTextView::Delete(int32 startOffset, int32 endOffset)
{
	CALLED();
	// anything to delete?
	if (startOffset == endOffset)
		return;

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

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

	fSelEnd = fSelStart = fClickOffset;

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

	// draw the caret
	if (fActive)
		_ShowCaret();
}


/*! \brief Returns the BTextView text as a C string.
	\return A pointer to the text.

	It is possible that the BTextView object had to do some operations
	on the text, to be able to return it as a C string.
	If you need to call Text() repeatedly, you'd better use GetText().
*/
const char *
BTextView::Text() const
{
	return fText->RealText();
}


/*! \brief Returns the length of the BTextView's text.
	\return The length of the text.
*/
int32
BTextView::TextLength() const
{
	return fText->Length();
}


void
BTextView::GetText(int32 offset, int32 length, char *buffer) const
{
	if (buffer != NULL)
		fText->GetString(offset, length, buffer);
}


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

	return fText->RealCharAt(offset);
}


/*! \brief Returns the number of lines that the object contains.
	\return The number of lines contained in the BTextView object.
*/
int32
BTextView::CountLines() const
{
	return fLines->NumLines();
}


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


/*! \brief Move the caret to the specified line.
	\param index The index of the line.
*/
void
BTextView::GoToLine(int32 index)
{
	CancelInputMethod();
	fSelStart = fSelEnd = fClickOffset = OffsetAt(index);
}


/*! \brief Cuts the current selection to the clipboard.
	\param clipboard The clipboard where to copy the cutted text.
*/
void
BTextView::Cut(BClipboard *clipboard)
{
	CancelInputMethod();
	if (fUndo) {
		delete fUndo;
		fUndo = new _BCutUndoBuffer_(this);
	}
	Copy(clipboard);
	Delete();
}


/*! \brief Copies the current selection to the clipboard.
	\param clipboard The clipboard where to copy the selected text.
*/
void
BTextView::Copy(BClipboard *clipboard)
{
	CancelInputMethod();

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

		BMessage *clip = clipboard->Data();
		if (clip != NULL) {
			clip->AddData("text/plain", B_MIME_TYPE, Text() + fSelStart,
				fSelEnd - fSelStart);

			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();
	}
}


/*! \brief Paste the text contained in the clipboard to the BTextView.
	\param clipboard A pointer to the clipboard.
*/
void
BTextView::Paste(BClipboard *clipboard)
{
	CALLED();
	CancelInputMethod();

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

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

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

				if (fUndo) {
					delete fUndo;
					fUndo = new _BPasteUndoBuffer_(this, text, len, runArray, runLen);
				}

				if (fSelStart != fSelEnd)
					Delete();

				Insert(text, len, runArray);
			}
		}

		clipboard->Unlock();
	}
}


/*! \brief 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 _BClearUndoBuffer_(this);
	}

	Delete();
}


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;
}


bool
BTextView::AcceptsDrop(const BMessage *inMessage)
{
	if (fEditable && inMessage && inMessage->HasData("text/plain", B_MIME_TYPE))
		return true;

	return false;
}


/*! \brief Selects the text within the given offsets.
	\param startOffset The offset of the text to select.
	\param endOffset The offset where the text ends.
*/
void
BTextView::Select(int32 startOffset, int32 endOffset)
{
	CALLED();
	if (!fSelectable)
		return;

	CancelInputMethod();

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

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

	// 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 = fClickOffset = startOffset;
	} 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 = fClickOffset = endOffset;
	}
}


/*! \brief Selects all the text within the BTextView.
*/
void
BTextView::SelectAll()
{
	Select(0, fText->Length());
}


/*! \brief Gets the current selection.
	\param outStart A pointer to an int32 which will contain the selection start's offset.
	\param outEnd A pointer to an int32 which will contain the selection end's offset.
*/
void
BTextView::GetSelection(int32 *outStart, int32 *outEnd) const
{
	int32 start = 0, end = 0;

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

	if (outStart)
		*outStart = start;
	if (outEnd)
		*outEnd = end;
}


void
BTextView::SetFontAndColor(const BFont *inFont, uint32 inMode, const rgb_color *inColor)
{
	SetFontAndColor(fSelStart, fSelEnd, inFont, inMode, inColor);
}


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

	if (startOffset > endOffset)
		return;

	BFont newFont;
	if (font != NULL) {
		newFont = font;
		NormalizeFont(&newFont);
	}

	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;
	}

	// 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;

	// add the style to the style buffer
	fStyles->SetStyleRange(startOffset, endOffset, fText->Length(),
		fontMode, &newFont, color);

	if (fontMode & B_FONT_FAMILY_AND_STYLE || fontMode & B_FONT_SIZE) {
		// recalc the line breaks and redraw with new style
		Refresh(startOffset, endOffset, startOffset != endOffset, false);
	} else {
		// the line breaks wont change, simply redraw
		DrawLines(LineAt(startOffset), LineAt(endOffset), startOffset, true);
	}
}


void
BTextView::GetFontAndColor(int32 inOffset, BFont *outFont, rgb_color *outColor) const
{
	fStyles->GetStyle(inOffset, outFont, outColor);
}


void
BTextView::GetFontAndColor(BFont *outFont, uint32 *outMode, rgb_color *outColor, bool *outEqColor) const
{
	fStyles->ContinuousGetStyle(outFont, outMode, outColor, outEqColor, fSelStart, fSelEnd);
}


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

	CancelInputMethod();

	_SetRunArray(startOffset, endOffset, inRuns);

	Refresh(startOffset, endOffset, true, false);
}


/*! \brief Returns a RunArray for the text within the given offsets.
	\param startOffset The offset where to start.
	\param endOffset The offset where the wanted text ends.
	\param outSize A pointer to an int32 which will contain the size
		of the run array.
	\return A text_run_array for the text in the given offsets.

	The returned text_run_array belongs to the caller, so you better
	free it as soon as you don't need it.
*/
text_run_array *
BTextView::RunArray(int32 startOffset, int32 endOffset, int32 *outSize) const
{
	STEStyleRange* styleRange = fStyles->GetStyleRange(startOffset, endOffset - 1);
	if (styleRange == NULL)
		return NULL;

	text_run_array *runArray = AllocRunArray(styleRange->count, outSize);
	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;
}


/*! \brief Returns the line number for the character at the given offset.
	\param offset The offset of the wanted character.
	\return A line number.
*/
int32
BTextView::LineAt(int32 offset) const
{
	return fLines->OffsetToLine(offset);
}


/*! \brief Returns the line number for the given point.
	\param point A point.
	\return A line number.
*/
int32
BTextView::LineAt(BPoint point) const
{
	return fLines->PixelToLine(point.y - fTextRect.top);
}


/*! \brief Returns the location of the character at the given offset.
	\param inOffset The offset of the character.
	\param outHeight Here the function will put the height of the character at the
	given offset.
	\return A BPoint which is the location of the character.
*/
BPoint
BTextView::PointAt(int32 inOffset, float *outHeight) const
{
	// TODO: Cleanup.
	const int32 textLength = fText->Length();
	int32 lineNum = LineAt(inOffset);
	STELine* line = (*fLines)[lineNum];
	float height = 0;

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

	// Handle the case where there is only one line
	// (no text inserted)
	// TODO: See if we can do this better
	if (fStyles->NumRuns() == 0) {
		const rgb_color *color = NULL;
		const BFont *font = NULL;
		fStyles->GetNullStyle(&font, &color);

		font_height fontHeight;
		font->GetHeight(&fontHeight);
		height = fontHeight.ascent + fontHeight.descent;

	} else {
		height = (line + 1)->origin - line->origin;

		// special case: go down one line if inOffset is a newline
		if (inOffset == textLength && fText->RealCharAt(inOffset - 1) == B_ENTER) {
			result.y += height;
			height = LineHeight(CountLines() - 1);

		} else {
			int32 offset = line->offset;
			int32 length = inOffset - line->offset;
			int32 numBytes = length;
			bool foundTab = false;
			do {
				foundTab = fText->FindChar(B_TAB, offset, &numBytes);

				float width = StyledWidth(offset, numBytes);

				result.x += width;

				if (foundTab) {
					result.x += ActualTabWidth(result.x);
					numBytes++;
				}

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

	if (fAlignment != B_ALIGN_LEFT) {
		float modifier = fTextRect.right - LineWidth(lineNum);
		if (fAlignment == B_ALIGN_CENTER)
			modifier /= 2;
		result.x += modifier;
	}
	// convert from text rect coordinates
	// NOTE: I didn't understand why "- 1.0"
	// and it works only correct without it on Haiku app_server.
	// Feel free to enlighten me though!
	result.x += fTextRect.left;// - 1.0;

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

	return result;
}


/*! \brief Returns the offset for the given location.
	\param point A BPoint which specify the wanted location.
	\return The offset for the given 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];

	// 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;
	}

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

	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;
}


/*! \brief Returns the offset of the given line.
	\param line A line number.
	\return The offset of the passed line.
*/
int32
BTextView::OffsetAt(int32 line) const
{
	if (line > fLines->NumLines())
		return fText->Length();

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


/*! \brief Looks for a sequence of character that qualifies as a word.
	\param inOffset The offset where to start looking.
	\param outFromOffset A pointer to an integer which will contain the starting offset of the word.
	\param outToOffset A pointer to an integer which will contain the ending offset of the word.
*/
void
BTextView::FindWord(int32 inOffset, int32 *outFromOffset, int32 *outToOffset)
{
	int32 offset;
	uint32 charType = CharClassification(inOffset);

	// check to the left
	int32 previous;
	for (offset = inOffset, previous = offset; offset > 0;
				previous = PreviousInitialByte(offset)) {
		if (CharClassification(previous) != charType)
			break;
		offset = previous;
	}

	if (outFromOffset)
		*outFromOffset = offset;

	// check to the right
	int32 textLen = TextLength();
	for (offset = inOffset; offset < textLen; offset = NextInitialByte(offset)) {
		if (CharClassification(offset) != charType)
			break;
	}

	if (outToOffset)
		*outToOffset = offset;
}


/*! \brief Returns true if the character at the given offset can be the last character in a line.
	\param offset The offset of the character.
	\return true if the character can be the last of a line, false if not.
*/
bool
BTextView::CanEndLine(int32 offset)
{
	// TODO: Could be improved, the bebook says there are other checks to do
	return (CharClassification(offset) == B_SEPARATOR_CHARACTER);
}


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

	STELine* line = (*fLines)[lineNum];
	return StyledWidth(line->offset, (line + 1)->offset - line->offset);
}


/*! \brief Returns the height of the line at the given index.
	\param lineNum A line index.
*/
float
BTextView::LineHeight(int32 lineNum) const
{
	return TextHeight(lineNum, lineNum);
}


/*! \brief Returns the height of the text comprised between the two given lines.
	\param startLine The index of the starting line.
	\param endLine The index of the ending line.
*/
float
BTextView::TextHeight(int32 startLine, int32 endLine) const
{
	const int32 numLines = fLines->NumLines();
	if (startLine < 0)
		startLine = 0;
	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();

	// 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);
	}
}


/*! \brief Scrolls the text so that the character at "inOffset" is within the visible range.
	\param inOffset The offset of the character.
*/
void
BTextView::ScrollToOffset(int32 inOffset)
{
	_ScrollToOffset(inOffset, ScrollBar(B_HORIZONTAL) != NULL, ScrollBar(B_VERTICAL) != NULL);
}

void
BTextView::_ScrollToOffset(int32 inOffset, bool useHorz, bool useVert)
{
	BRect bounds = Bounds();
	float lineHeight = 0.0;
	float xdiff = 0.0;
	float ydiff = 0.0;
        BPoint point = PointAt(inOffset, &lineHeight);

	if (useHorz) {
		if (point.x < bounds.left) {
			xdiff = -1 * (bounds.IntegerWidth() / 2);
			// normalize scroll value to prevent scrolling past left boundary of view
			if (bounds.left < fabs(xdiff))
				xdiff = -1 * bounds.left;
		} else if (point.x >= bounds.right)
			xdiff = bounds.IntegerWidth() / 2;
	}

	if (useVert) {
		if (point.y < bounds.top) {
			ydiff = -1 * (bounds.IntegerHeight() / 2);
			// normalize scroll value to prevent scrolling past top of view
			if (bounds.top < fabs(ydiff))
			ydiff = -1 * bounds.top;
		} else if (point.y >= bounds.bottom)
			ydiff = bounds.IntegerHeight() / 2;
	}

	ScrollBy(xdiff, ydiff);
}


/*! \brief Scrolls the text so that the character which begins the current selection
		is within the visible range.
	\param inOffset The offset of the character.
*/
void
BTextView::ScrollToSelection()
{
	ScrollToOffset(fSelStart);
}


/*! \brief Highlight the text comprised between the given offset.
	\param startOffset The offset of the text to highlight.
	\param endOffset The offset where the text to highlight ends.
*/
void
BTextView::Highlight(int32 startOffset, int32 endOffset)
{
	// get real
	if (startOffset >= endOffset)
		return;

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

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


/*! \brief Sets the BTextView's text rectangle to be the same as the passed rect.
	\param rect A BRect.
*/
void
BTextView::SetTextRect(BRect rect)
{
	if (rect == fTextRect)
		return;

	fTextRect = rect;

	if (Window() != NULL) {
		Invalidate();
		Window()->UpdateIfNeeded();
	}
}


/*! \brief Returns the current BTextView's text rectangle.
	\return The current text rectangle.
*/
BRect
BTextView::TextRect() const
{
	return fTextRect;
}


/*! \brief Sets whether the BTextView accepts multiple character styles.
*/
void
BTextView::SetStylable(bool stylable)
{
	fStylable = stylable;
}


/*! \brief Tells if the object is stylable.
	\return true if the object is stylable, false otherwise.
	If the object is stylable, it can show multiple fonts at the same time.
*/
bool
BTextView::IsStylable() const
{
	return fStylable;
}


/*! \brief Sets the distance between tab stops (in pixel).
	\param width The distance (in pixel) between tab stops.
*/
void
BTextView::SetTabWidth(float width)
{
	if (width == fTabWidth)
		return;

	fTabWidth = width;

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


/*! \brief Returns the BTextView's tab width.
	\return The BTextView's tab width.
*/
float
BTextView::TabWidth() const
{
	return fTabWidth;
}


/*! \brief Makes the object selectable, or not selectable.
	\param selectable If true, the object will be selectable from now on.
	 if false, it won't be selectable anymore.
*/
void
BTextView::MakeSelectable(bool selectable)
{
	if (selectable == fSelectable)
		return;

	fSelectable = selectable;

	if (Window() != NULL) {
		if (fActive) {
			// show/hide the caret, hilite/unhilite the selection
			if (fSelStart != fSelEnd)
				Highlight(fSelStart, fSelEnd);
			else
				InvertCaret();
		}
	}
}


/*! \brief Tells if the object is selectable
	\return \c true if the object is selectable,
			\c false if not.
*/
bool
BTextView::IsSelectable() const
{
	return fSelectable;
}


/*! \brief Set (or remove) the editable property for the object.
	\param editable If true, will make the object editable,
		if false, will make it not 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();
		}
	}
}


/*! \brief Tells if the object is editable.
	\return \c true if the object is editable,
			\c false if not.
*/
bool
BTextView::IsEditable() const
{
	return fEditable;
}


/*! \brief Set (or unset) word wrapping mode.
	\param wrap Specifies if you want word wrapping active or not.
*/
void
BTextView::SetWordWrap(bool wrap)
{
	if (wrap == fWrap)
		return;

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

		fWrap = wrap;
		Refresh(0, fText->Length(), true, true);

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


/*! \brief Tells if word wrapping is activated.
	\return true if word wrapping is active, false otherwise.
*/
bool
BTextView::DoesWordWrap() const
{
	return fWrap;
}


/*! \brief Sets the maximun number of bytes that the BTextView can contain.
	\param max The new max number of bytes.
*/
void
BTextView::SetMaxBytes(int32 max)
{
	const int32 textLength = fText->Length();
	fMaxBytes = max;

	if (fMaxBytes < textLength)
		Delete(fMaxBytes, textLength);
}


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


/*! \brief Adds the given char to the disallowed chars list.
	\param aChar The character to add to the list.

	After this function returns, the given character won't be accepted
	by the textview anymore.
*/
void
BTextView::DisallowChar(uint32 aChar)
{
	if (fDisallowedChars == NULL)
		fDisallowedChars = new BList;
	if (!fDisallowedChars->HasItem(reinterpret_cast<void *>(aChar)))
		fDisallowedChars->AddItem(reinterpret_cast<void *>(aChar));
}


/*! \brief Removes the given character from the disallowed list.
	\param aChar The character to remove from the list.
*/
void
BTextView::AllowChar(uint32 aChar)
{
	if (fDisallowedChars != NULL)
		fDisallowedChars->RemoveItem(reinterpret_cast<void *>(aChar));
}


/*! \brief Sets the way text is aligned within the text rectangle.
	\param flag The new alignment.
*/
void
BTextView::SetAlignment(alignment flag)
{
	// Do a reality check
	if (fAlignment != flag &&
			(flag == B_ALIGN_LEFT ||
			 flag == B_ALIGN_RIGHT ||
			 flag == B_ALIGN_CENTER)) {
		fAlignment = flag;

		// After setting new alignment, update the view/window
		BWindow *window = Window();
		if (window) {
			Invalidate();
			window->UpdateIfNeeded();
		}
	}
}


/*! \brief Returns the current alignment of the text.
	\return The current alignment.
*/
alignment
BTextView::Alignment() const
{
	return fAlignment;
}


/*! \brief Sets wheter a new line of text is automatically indented.
	\param state The new autoindent state
*/
void
BTextView::SetAutoindent(bool state)
{
	fAutoindent = state;
}


/*! \brief Returns the current autoindent state.
	\return The current autoindent state.
*/
bool
BTextView::DoesAutoindent() const
{
	return fAutoindent;
}


/*! \brief Set the color space for the offscreen BBitmap.
	\param colors The new colorspace for the offscreen BBitmap.
*/
void
BTextView::SetColorSpace(color_space colors)
{
	if (colors != fColorSpace && fOffscreen) {
		fColorSpace = colors;
		DeleteOffscreen();
		NewOffscreen();
	}
}


/*! \brief Returns the colorspace of the offscreen BBitmap, if any.
	\return The colorspace of the BTextView's offscreen BBitmap.
*/
color_space
BTextView::ColorSpace() const
{
	return fColorSpace;
}


/*! \brief Gives to the BTextView the ability to automatically resize itself when needed.
	\param resize If true, the BTextView will automatically resize itself.
	\param resizeView The BTextView's parent view, it's the view which resizes itself.
	The resizing mechanism is alternative to the BView resizing. The container view
	(the one passed to this function) should not automatically resize itself when the parent is
	resized.
*/
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 && fSelectable)
					Highlight(fSelStart, fSelEnd);

				else
					_HideCaret();
			}
		}
	} else {
		fResizable = false;
		fContainerView = NULL;
		if (fOffscreen)
			DeleteOffscreen();
		NewOffscreen();
	}

	Refresh(0, fText->Length(), true, false);
}


/*! \brief Returns whether the BTextView is currently resizable.
	\returns whether the BTextView is currently resizable.
*/
bool
BTextView::IsResizable() const
{
	return fResizable;
}


/*! \brief Enables or disables the undo mechanism.
	\param undo If true enables the undo mechanism, if false, disables it.
*/
void
BTextView::SetDoesUndo(bool undo)
{
	if (undo && fUndo == NULL)
		fUndo = new _BUndoBuffer_(this, B_UNDO_UNAVAILABLE);
	else if (!undo && fUndo != NULL) {
		delete fUndo;
		fUndo = NULL;
	}
}


/*! \brief Tells if the object is undoable.
	\return Whether the object is undoable.
*/
bool
BTextView::DoesUndo() const
{
	return fUndo != NULL;
}


void
BTextView::HideTyping(bool enabled)
{
	if (enabled)
		Delete(0, fText->Length());

	fText->SetPasswordMode(enabled);
}


bool
BTextView::IsTypingHidden() const
{
	return fText->PasswordMode();
}


void
BTextView::ResizeToPreferred()
{
	float widht, height;
	GetPreferredSize(&widht, &height);
	BView::ResizeTo(widht, height);
}


void
BTextView::GetPreferredSize(float *width, float *height)
{
	BView::GetPreferredSize(width, height);
}


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 *inText, int32 inLength, int32 inOffset,
						   const text_run_array *inRuns)
{
	CALLED();
	// why add nothing?
	if (inLength < 1)
		return;

	// TODO: Pin offset/lenght
	// add the text to the buffer
	fText->InsertText(inText, inLength, inOffset);

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

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

	if (inRuns != NULL) {
		_SetRunArray(inOffset, inOffset + inLength, inRuns);
	} else {
		// apply nullStyle to inserted text
		fStyles->SyncNullStyle(inOffset);
		fStyles->SetStyleRange(inOffset, inOffset + inLength,
							  fText->Length(), B_FONT_ALL, NULL, NULL);
	}
}


void
BTextView::DeleteText(int32 fromOffset, int32 toOffset)
{
	CALLED();
	// sanity checking
	if (fromOffset >= toOffset || fromOffset < 0 || toOffset > fText->Length())
		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);
}


/*! \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
	drag->AddData("text/plain", B_MIME_TYPE, fText->RealText() + fSelStart,
			  	  fSelEnd - fSelStart);

	// 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() {}


/*! \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 _BTextGapBuffer_;
	fLines = new _BLineBuffer_;
	fStyles = new _BStyleBuffer_(&font, initialColor);

	// 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;
	fSelStart = fSelEnd = 0;
	fCaretVisible = false;
	fCaretTime = 0;
	fClickOffset = 0;
	fClickCount = 0;
	fClickTime = 0;
	fDragOffset = -1;
	fCursor = 0;
	fActive = false;
	fStylable = false;
	fTabWidth = 28.0;
	fSelectable = true;
	fEditable = true;
	fWrap = true;
	fMaxBytes = LONG_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;
	fTextChange = NULL;
}


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

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

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

	Refresh(fSelStart, fSelEnd, true, true);
}


/*! \brief Called when any arrow key is pressed.
	\param inArrowKey The code for the pressed key.
*/
void
BTextView::HandleArrowKey(uint32 inArrowKey)
{
	// return if there's nowhere to go
	if (fText->Length() == 0)
		return;

	int32 selStart = fSelStart;
	int32 selEnd = fSelEnd;

	int32 modifiers = 0;
	BMessage *message = Window()->CurrentMessage();
	if (message != NULL)
		message->FindInt32("modifiers", &modifiers);

	bool shiftDown = modifiers & B_SHIFT_KEY;

	int32 currentOffset = fClickOffset;
	switch (inArrowKey) {
		case B_LEFT_ARROW:
			if (shiftDown) {
				fClickOffset = PreviousInitialByte(fClickOffset);
				if (fClickOffset != currentOffset) {
					if (fClickOffset >= fSelStart)
						selEnd = fClickOffset;
					else
						selStart = fClickOffset;
				}
			} else if (fSelStart != fSelEnd)
				fClickOffset = fSelStart;
			else
				fClickOffset = PreviousInitialByte(fSelStart);

			break;

		case B_RIGHT_ARROW:
			if (shiftDown) {
				fClickOffset = NextInitialByte(fClickOffset);
				if (fClickOffset != currentOffset) {
					if (fClickOffset <= fSelEnd)
						selStart = fClickOffset;
					else
						selEnd = fClickOffset;
				}
			} else if (fSelStart != fSelEnd)
				fClickOffset = fSelEnd;
			else
				fClickOffset = NextInitialByte(fSelEnd);
			break;

		case B_UP_ARROW:
		{
			float height;
			BPoint point = PointAt(fClickOffset, &height);
			point.y -= height;
			fClickOffset = OffsetAt(point);
			if (shiftDown) {
				if (fClickOffset != currentOffset) {
					if (fClickOffset >= fSelStart)
						selEnd = fClickOffset;
					else
						selStart = fClickOffset;
				}
			}
			break;
		}

		case B_DOWN_ARROW:
		{
			float height;
			BPoint point = PointAt(fClickOffset, &height);
			point.y += height;
			fClickOffset = OffsetAt(point);
			if (shiftDown) {
				if (fClickOffset != currentOffset) {
					if (fClickOffset <= fSelEnd)
						selStart = fClickOffset;
					else
						selEnd = fClickOffset;
				}
			}
			break;
		}
	}

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

	currentOffset = fClickOffset;
	if (shiftDown)
		Select(selStart, selEnd);
	else
		Select(fClickOffset, fClickOffset);

	fClickOffset = currentOffset;
		// Select sets fClickOffset = fSelEnd

	// scroll if needed
	ScrollToOffset(fClickOffset);
}


/*! \brief Called when the Delete key is pressed.
*/
void
BTextView::HandleDelete()
{
	if (fUndo) {
		_BTypingUndoBuffer_ *undoBuffer = dynamic_cast<_BTypingUndoBuffer_ *>(fUndo);
		if (!undoBuffer) {
			delete fUndo;
			fUndo = undoBuffer = new _BTypingUndoBuffer_(this);
		}
		undoBuffer->ForwardErase();
	}

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

	DeleteText(fSelStart, fSelEnd);

	fClickOffset = fSelEnd = fSelStart;

	Refresh(fSelStart, fSelEnd, true, true);
}


/*! \brief Called when a "Page key" is pressed.
	\param inPageKey The page key which has been pressed.
*/
void
BTextView::HandlePageKey(uint32 inPageKey)
{
	int32 mods = 0;
	BMessage *currentMessage = Window()->CurrentMessage();
	if (currentMessage)
		currentMessage->FindInt32("modifiers", &mods);

	bool shiftDown = mods & B_SHIFT_KEY;

	STELine* line = NULL;

	int32 start = fSelStart, end = fSelEnd;

	switch (inPageKey) {
		case B_HOME:
			line = (*fLines)[CurrentLine()];
			fClickOffset = line->offset;
			if (shiftDown) {
				if (fClickOffset <= fSelStart) {
					start = fClickOffset;
					end = fSelEnd;
				} else {
					start = fSelStart;
					end = fClickOffset;
				}
			} else
				start = end = fClickOffset;

			break;

		case B_END:
			// 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
			if (CurrentLine() + 1 < fLines->NumLines()) {
				line = (*fLines)[CurrentLine() + 1];
				fClickOffset = PreviousInitialByte(line->offset);
			} else {
				// This check if needed to avoid moving the cursor
				// when the cursor is on the last line, and that line
				// is empty
				if (fClickOffset != fText->Length()) {
					fClickOffset = fText->Length();
					if (ByteAt(fClickOffset - 1) == B_ENTER)
						fClickOffset--;
				}
			}

			if (shiftDown) {
				if (fClickOffset >= fSelEnd) {
					start = fSelStart;
					end = fClickOffset;
				} else {
					start = fClickOffset;
					end = fSelEnd;
				}
			} else
				start = end = fClickOffset;

			break;

		case B_PAGE_UP:
		{
			BPoint currentPos = PointAt(fClickOffset);

			currentPos.y -= Bounds().Height();
			fClickOffset = OffsetAt(LineAt(currentPos));

			if (shiftDown) {
				if (fClickOffset <= fSelStart) {
					start = fClickOffset;
					end = fSelEnd;
				} else {
					start = fSelStart;
					end = fClickOffset;
				}
			} else
				start = end = fClickOffset;

			break;
		}

		case B_PAGE_DOWN:
		{
			BPoint currentPos = PointAt(fClickOffset);

			currentPos.y += Bounds().Height();
			fClickOffset = OffsetAt(LineAt(currentPos) + 1);

			if (shiftDown) {
				if (fClickOffset >= fSelEnd) {
					start = fSelStart;
					end = fClickOffset;
				} else {
					start = fClickOffset;
					end = fSelEnd;
				}
			} else
				start = end = fClickOffset;

			break;
		}
	}

	ScrollToOffset(fClickOffset);
	Select(start, end);
}


/*! \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) {
		_BTypingUndoBuffer_ *undoBuffer = dynamic_cast<_BTypingUndoBuffer_ *>(fUndo);
		if (!undoBuffer) {
			delete fUndo;
			fUndo = undoBuffer = new _BTypingUndoBuffer_(this);
		}
		undoBuffer->InputCharacter(numBytes);
	}

	bool erase = fSelStart != fText->Length();
	int32 saveStart = fSelStart;

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

	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++;

		if (start != offset)
			InsertText(Text() + start, offset - start, fSelStart, NULL);

		InsertText(bytes, numBytes, fSelStart, NULL);
		numBytes += offset - start;

	} else
		InsertText(bytes, numBytes, fSelStart, NULL);

	fClickOffset = fSelEnd = fSelStart = fSelStart + numBytes;

	if (Window())
		Refresh(saveStart, fSelEnd, erase, true);
}


/*! \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 erase If true, the function will also erase the textview content
	in the parts where text isn't present.
	\param scroll If true, function will scroll the view to the end offset.
*/
void
BTextView::Refresh(int32 fromOffset, int32 toOffset, bool erase, bool scroll)
{
	// TODO: Cleanup
	float saveHeight = fTextRect.Height();
	int32 fromLine = LineAt(fromOffset);
	int32 toLine = LineAt(toOffset);
	int32 saveFromLine = fromLine;
	int32 saveToLine = toLine;
	float saveLineHeight = LineHeight(fromLine);

	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 ) {
		erase = true;
		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);

	int32 drawOffset = fromOffset;
	if (LineHeight(fromLine) != saveLineHeight ||
		 newHeight < saveHeight || fromLine < saveFromLine || fAlignment != B_ALIGN_LEFT)
		drawOffset = (*fLines)[fromLine]->offset;

	if (fResizable)
		AutoResize(false);

	DrawLines(fromLine, toLine, drawOffset, erase);

	// 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)
		UpdateScrollbars();

	if (scroll)
		ScrollToSelection();

	Flush();
}


void
BTextView::RecalculateLineBreaks(int32 *startLine, int32 *endLine)
{
	// 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 = fTextRect.Width();
	STELine* curLine = (*fLines)[lineIndex];
	STELine* nextLine = curLine + 1;

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

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

		// set the ascent of this line
		curLine->ascent = ascent;

		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 exising 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);

	// update the text rect
	float newHeight = TextHeight(0, fLines->NumLines() - 1);
	fTextRect.bottom = fTextRect.top + newHeight;

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


int32
BTextView::FindLineBreak(int32 fromOffset, float *outAscent, float *outDescent, float *ioWidth)
{
	*outAscent = 0.0;
	*outDescent = 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, outAscent, outDescent);
		else {
			if (fStyles->IsValidNullStyle()) {
				const BFont *font = NULL;
				fStyles->GetNullStyle(&font, NULL);

				font_height fh;
				font->GetHeight(&fh);
				*outAscent = fh.ascent;
				*outDescent = fh.descent + fh.leading;
			}
		}

		return limit;
	}

	int32 offset = fromOffset;

	// Text wrapping is turned off.
	// Just find the offset of the first \n character
	if (!fWrap) {
		offset = limit - fromOffset;
		fText->FindChar(B_ENTER, fromOffset, &offset);
		offset += fromOffset;
		offset = (offset < limit) ? offset + 1 : limit;

		*ioWidth = StyledWidth(fromOffset, offset - fromOffset, outAscent, outDescent);

		return offset;
	}

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

	// wrap the text
	do {
		bool foundTab = false;

		// find the next line break candidate
		for ( ; (offset + delta) < limit ; delta++) {
			if (CanEndLine(offset + delta))
				break;
		}
		for ( ; (offset + delta) < limit; delta++) {
			uchar theChar = fText->RealCharAt(offset + delta);
			if (!CanEndLine(offset + delta))
				break;

			if (theChar == B_ENTER) {
				// found a newline, we're done!
				done = true;
				delta++;
				break;
			} else {
				// include all trailing spaces and tabs,
				// but not spaces after tabs
				if (theChar != B_SPACE && theChar != B_TAB)
					break;
				else {
					if (theChar == B_SPACE && foundTab)
						break;
					else {
						if (theChar == B_TAB)
							foundTab = true;
					}
				}
			}
		}
		delta = max_c(delta, 1);

		deltaWidth = StyledWidth(offset, delta, &ascent, &descent);
		strWidth += deltaWidth;

		if (!foundTab)
			tabWidth = 0.0;
		else {
			int32 tabCount = 0;
			for (int32 i = delta - 1; fText->RealCharAt(offset + i) == B_TAB; i--)
				tabCount++;

			tabWidth = ActualTabWidth(strWidth);
			if (tabCount > 1)
				tabWidth += ((tabCount - 1) * fTabWidth);
			strWidth += tabWidth;
		}

		if (strWidth >= *ioWidth) {
			// we've found where the line will wrap
			bool foundNewline = done;
			done = true;
			int32 pos = delta - 1;
			if (!CanEndLine(offset + pos))
				break;

			strWidth -= (deltaWidth + tabWidth);

			for ( ; ((offset + pos) > offset); pos--) {
				if (!CanEndLine(offset + pos))
					break;
			}

			strWidth += StyledWidth(offset, pos + 1, &ascent, &descent);
			if (strWidth >= *ioWidth)
				break;

			if (!foundNewline) {
				for ( ; (offset + delta) < limit; delta++) {
					const char realChar = fText->RealCharAt(offset + delta);
					if (realChar != B_SPACE
						&& realChar != B_TAB)
						break;
				}
				if ((offset + delta) < limit
					&& fText->RealCharAt(offset + delta) == B_ENTER )
					delta++;
			}
			// get the ascent and descent of the spaces/tabs
			StyledWidth(offset, delta, &ascent, &descent);
		}

		*outAscent = max_c(ascent, *outAscent);
		*outDescent = max_c(descent, *outDescent);

		offset += delta;
		delta = 0;
	} while (offset < limit && !done);

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

		int32 current = fromOffset;
		for (offset = fromOffset; offset <= limit; current = offset, offset = NextInitialByte(offset)) {
			strWidth += StyledWidth(current, offset - current, &ascent, &descent);

			if (strWidth >= *ioWidth) {
				offset = PreviousInitialByte(offset);
				break;
			}

			*outAscent = max_c(ascent, *outAscent);
			*outDescent = max_c(descent, *outDescent);
		}
	}

	return min_c(offset, limit);
}


/*! \brief Calculate the width of the text within the given limits.
	\param fromOffset The offset where to start.
	\param length The length of the text to examine.
	\param outAscent A pointer to a float which will contain the maximum ascent.
	\param outDescent 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 *outAscent,
							 float *outDescent) const
{
	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 numChars;
	while ((numChars = 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 (sWidths != NULL) {
			LockWidthBuffer();
			result += sWidths->StringWidth(*fText, fromOffset, numChars, font);
			UnlockWidthBuffer();
		} else
#endif
			result += font->StringWidth(fText->RealText() + fromOffset, numChars);

		fromOffset += numChars;
		length -= numChars;
	}

	if (outAscent != NULL)
		*outAscent = maxAscent;
	if (outDescent != NULL)
		*outDescent = maxDescent;

	return result;
}


// Unlike the StyledWidth method, this one takes as parameter
// the number of chars, not the number of bytes.
float
BTextView::StyledWidthUTF8Safe(int32 fromOffset, int32 numChars,
					float *outAscent, float *outDescent) const
{
	int32 toOffset = fromOffset;
	while (numChars--)
		toOffset = NextInitialByte(toOffset);

	const int32 length = toOffset - fromOffset;
	return StyledWidth(fromOffset, length, outAscent, outDescent);
}


/*! \brief Calculate the actual tab width for the given location.
	\param location The location to calculate the tab width of.
	\return The actual tab width for the given location
*/
float
BTextView::ActualTabWidth(float location) const
{
	return fTabWidth - fmod(location, fTabWidth);
}


void
BTextView::DoInsertText(const char *inText, int32 inLength, int32 inOffset,
				const text_run_array *inRuns, _BTextChangeResult_ *outResult)
{
	CancelInputMethod();

	// Don't do any check, the public methods will have adjusted
	// eventual bogus values...

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

	// copy data into buffer
	InsertText(inText, inLength, inOffset, inRuns);

	// offset the caret/selection
	int32 saveStart = fSelStart;
	fSelStart += inLength;
	fSelEnd += inLength;

	// recalc line breaks and draw the text
	Refresh(saveStart, fSelEnd, true, false);
}


void
BTextView::DoDeleteText(int32 fromOffset, int32 toOffset, _BTextChangeResult_ *outResult)
{
	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;
	}

	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--;
	if (fAlignment != B_ALIGN_LEFT) {
		// B_ALIGN_RIGHT
		startLeft = (fTextRect.right - LineWidth(lineNum));
		if (fAlignment == B_ALIGN_CENTER)
			startLeft /= 2;
		startLeft += fTextRect.left;
	}

	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) {
		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;
		// iterate through each style on this line
		while ((numBytes = fStyles->Iterate(offset, length, fInline, &font, &color)) != 0) {
			view->SetFont(font);
			view->SetHighColor(*color);

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

				if (inputRegion.CountRects() > 0) {
					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->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 = numBytes;
				numTabs = 0;
			} while (foundTab && tabChars > 0);
		}
	}
}


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

	// clip the text
	BRect clipRect = Bounds() & fTextRect;
	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;

	// Actually hide the caret
	if (fCaretVisible)
		DrawCaret(fSelStart);

	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 && fSelectable)
			Highlight(fSelStart, fSelEnd);
		else {
			if (fCaretVisible)
				DrawCaret(fSelStart);
		}
	}

	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::DrawCaret(int32 offset)
{
	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;

	InvertRect(caretRect);
}


inline void
BTextView::_ShowCaret()
{
	if (!fCaretVisible)
		InvertCaret();
}


inline void
BTextView::_HideCaret()
{
	if (fCaretVisible)
		InvertCaret();
}


/*! \brief Inverts the blinking caret status.
	Hides the caret if it is being shown, and if it's hidden, shows it.
*/
void
BTextView::InvertCaret()
{
	DrawCaret(fSelStart);
	fCaretVisible = !fCaretVisible;
	fCaretTime = system_time();
}


/*! \brief Place the dragging caret at the given offset.
	\param 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);

	// 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);
	}

	fDragOffset = offset;
}


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


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

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

	StopMouseTracking();

	return true;
}


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

	if (fTrackingMouse == NULL)
		return false;

	if (fTrackingMouse->selectionRect.IsValid() && fTrackingMouse->selectionRect.Contains(where)) {
		StopMouseTracking();
		InitiateDrag();
		return true;
	}

	int32 oldOffset = fTrackingMouse->anchor;
	int32 currentOffset = OffsetAt(where);

	switch (fClickCount) {
		case 0:
			// triple click, select line by line
			fTrackingMouse->selStart = (*fLines)[LineAt(fTrackingMouse->selStart)]->offset;
			fTrackingMouse->selEnd = (*fLines)[LineAt(fTrackingMouse->selEnd) + 1]->offset;
			break;

		case 2:
			// double click, select word by word
			FindWord(currentOffset, &fTrackingMouse->selStart, &fTrackingMouse->selEnd);
			break;

		default:
			// new click, select char by char
			if (oldOffset < currentOffset) {
				fTrackingMouse->selStart = oldOffset;
				fTrackingMouse->selEnd = currentOffset;
			} else {
				fTrackingMouse->selStart = currentOffset;
				fTrackingMouse->selEnd = oldOffset;
			}
			break;
	}

	Select(fTrackingMouse->selStart, fTrackingMouse->selEnd);

	TrackMouse(where, NULL);

	return true;
}


/*! \brief Tracks the mouse position, doing special actions like changing the view cursor.
	\param where The point where the mouse has moved.
	\param message The dragging message, if there is any.
	\param 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) && !textRegion.Contains(where))
		SetViewCursor(B_CURSOR_I_BEAM, force);
	else
		SetViewCursor(B_CURSOR_SYSTEM_DEFAULT, force);
}


/*! \brief Tracks the mouse position when the user is dragging some data.
	\param where The point where the mouse has moved.
*/
void
BTextView::TrackDrag(BPoint where)
{
	CALLED();
	if (Bounds().Contains(where))
		DragCaret(OffsetAt(where));
}


/*! \brief Function called to initiate a drag operation.
*/
void
BTextView::InitiateDrag()
{
	BMessage *dragMessage = new BMessage(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);
}


/*! \brief Called when some data is dropped on the view.
	\param inMessage The message which has been dropped.
	\param where The location where the message has been dropped.
	\param offset ?
	\return \c true if the message was handled, \c false if not.
*/
bool
BTextView::MessageDropped(BMessage *inMessage, BPoint where, BPoint offset)
{
	ASSERT(inMessage);

	void *from = NULL;
	bool internalDrop = false;
	if (inMessage->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(inMessage))
		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 dataLen = 0;
	const char *text = NULL;
	if (inMessage->FindData("text/plain", B_MIME_TYPE, (const void **)&text, &dataLen) == B_OK) {
		text_run_array *runArray = NULL;
		ssize_t runLen = 0;
		if (fStylable)
			inMessage->FindData("application/x-vnd.Be-text_run_array", B_MIME_TYPE,
					(const void **)&runArray, &runLen);

		if (fUndo) {
			delete fUndo;
			fUndo = new _BDropUndoBuffer_(this, text, dataLen, runArray, runLen, dropOffset, internalDrop);
		}

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

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

	return true;
}


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

	BPoint constraint = fWhere;
	constraint.ConstrainTo(bounds);
	// Scroll char by char horizontally
	// TODO: Check how BeOS R5 behaves
	float value = StyledWidthUTF8Safe(OffsetAt(constraint), 1);
	if (fWhere.x > bounds.right) {
		if (bounds.right + value <= fTextRect.Width())
			scrollBy.x = value;
	} else if (fWhere.x < bounds.left) {
		if (bounds.left - value >= 0)
			scrollBy.x = -value;
	}

	float lineHeight = 0;
	float vertDiff = 0;
	if (fWhere.y > bounds.bottom) {
		lineHeight = LineHeight(LineAt(bounds.LeftBottom()));
		vertDiff = fWhere.y - bounds.bottom;
	} else if (fWhere.y < bounds.top) {
		lineHeight = LineHeight(LineAt(bounds.LeftTop()));
		vertDiff = fWhere.y - bounds.top; // negative value
	}

	// Always scroll vertically line by line or by multiples of that
	// based on the distance of the cursor from the border of the view
	// TODO: Refine this, I can't even remember how beos works here
	scrollBy.y = lineHeight > 0 ? lineHeight * (int32)(floorf(vertDiff) / lineHeight) : 0;

	if (bounds.bottom + scrollBy.y > fTextRect.Height())
		scrollBy.y = fTextRect.Height() - bounds.bottom;
	else if (bounds.top + scrollBy.y < 0)
		scrollBy.y = -bounds.top;

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


/*! \brief 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 = fTextRect.IntegerWidth();
		dataWidth += (long)ceilf(fTextRect.left) + 1;

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

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

	// how about a vertical scroll bar?
	if (verticalScrollBar != NULL) {
		long viewHeight = bounds.IntegerHeight();
		long dataHeight = fTextRect.IntegerHeight();
		dataHeight += (long)ceilf(fTextRect.top) + 1;

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

		verticalScrollBar->SetRange(0, maxRange);
		verticalScrollBar->SetProportion((float)viewHeight / (float)dataHeight);
		verticalScrollBar->SetSteps(12, viewHeight);
	}
}


/*!	\brief Autoresizes the view to fit the contained text.
*/
void
BTextView::AutoResize(bool redraw)
{
	if (fResizable) {
		float oldWidth = Bounds().Width() + 1;
		float newWidth = 3;
		for (int32 i = 0; i < CountLines(); i++)
			newWidth += LineWidth(i);

		BRect newRect(0, 0, ceilf(newWidth), ceilf(LineHeight(0)) + 2);

		if (fContainerView != NULL) {
			fContainerView->ResizeTo(newRect.Width() + 1, newRect.Height());
			if (fAlignment == B_ALIGN_CENTER)
				fContainerView->MoveBy(ceilf((oldWidth - (newRect.Width() + 1)) / 2), 0);
			else if (fAlignment == B_ALIGN_RIGHT)
				fContainerView->MoveBy(oldWidth - (newRect.Width() + 1), 0);
			fContainerView->Invalidate();
		}

		fTextRect = newRect.InsetBySelf(0, 1);

		if (redraw)
			DrawLines(0, 0);

		// Erase the old text (TODO: Might not work for alignments different than B_ALIGN_LEFT)
		SetLowColor(ViewColor());
		FillRect(BRect(fTextRect.right, fTextRect.top, Bounds().right, fTextRect.bottom), B_SOLID_LOW);
	}
}


/*! \brief Creates a new offscreen BBitmap with an associated BView.
	param padding Padding (?)

	Creates an offscreen BBitmap which will be used to draw.
*/
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
}


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


/*!	\brief 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 {
		if (fEditable)
			_ShowCaret();
	}

	BPoint where;
	ulong buttons;
	GetMouse(&where, &buttons, false);
	if (Bounds().Contains(where))
		TrackMouse(where, NULL);
}


/*! \brief 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();

	BPoint where;
	ulong buttons;
	GetMouse(&where, &buttons);
	if (Bounds().Contains(where))
		SetViewCursor(B_CURSOR_SYSTEM_DEFAULT);
}


/*! \brief Changes the passed font to be displayable by the object.
	\param font A pointer to the font to normalize.

	Set font rotation to 0, removes any font flag, set font spacing
	to \c B_BITMAP_SPACING and font encoding to \c 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 *inRuns)
{
	if (startOffset > endOffset)
		return;

	const int32 textLength = fText->Length();

	// 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;

	const int32 numStyles = inRuns->count;
	if (numStyles > 0) {
		const text_run *theRun = &inRuns->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;
			}

			BFont font = theRun->font;
			NormalizeFont(&font);
			fStyles->SetStyleRange(fromOffset, toOffset, textLength,
							  	  B_FONT_ALL, &theRun->font, &theRun->color);

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


/*! \brief Returns a value which tells if the given character is a separator
	character or not.
	\param 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 B_SPACE:
		case '_':
		case '.':
		case '\0':
		case B_TAB:
		case B_ENTER:
		case '&':
		case '*':
		case '+':
		case '-':
		case '/':
		case '<':
		case '=':
		case '>':
		case '\\':
		case '^':
		case '|':
			return B_SEPARATOR_CHARACTER;
		default:
			return B_OTHER_CHARACTER;
	}
}


/*! \brief Returns the offset of the next UTF8 character within the BTextView's text.
	\param offset The offset where to start looking.
	\return The offset of the next UTF8 character.
*/
int32
BTextView::NextInitialByte(int32 offset) const
{
	int32 textLength = TextLength();
	if (offset >= textLength)
		return textLength;

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

	return offset;
}


/*! \brief Returns the offset of the previous UTF8 character within the BTextView's text.
	\param 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);
		delete buffer;
		reply->AddInt32("error", B_OK);

		return true;

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

	else
		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;
}


/*! \brief Called when the object receives a B_INPUT_METHOD_CHANGED message.
	\param message 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();

	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 _BInlineInput_ 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);
		fClickOffset = 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 _BInlineInput_ 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++;
	}

	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);
	fSelStart += stringLen;
	fClickOffset = fSelEnd = fSelStart;

	Refresh(inlineOffset, fSelEnd, true, true);

	_ShowCaret();
}


/*! \brief 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);
}


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

	_BInlineInput_ *inlineInput = fInline;
	fInline = NULL;

	if (inlineInput->IsActive() && Window())
		Refresh(inlineInput->Offset(), fText->Length() - inlineInput->Offset(), true, false);

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

	delete inlineInput;
}


/*! \brief Locks the static _BWidthBuffer_ object to be able to access it safely.
*/
void
BTextView::LockWidthBuffer()
{
	if (atomic_add(&sWidthAtom, 1) > 0) {
		while (acquire_sem(sWidthSem) == B_INTERRUPTED)
			;
	}
}


/*! \brief Unlocks the static _BWidthBuffer_ object.
*/
void
BTextView::UnlockWidthBuffer()
{
	if (atomic_add(&sWidthAtom, -1) > 1)
		release_sem(sWidthSem);
}


// _BTextTrackState_
_BTextTrackState_::_BTextTrackState_(BMessenger messenger)
	:
	clickOffset(0),
	shiftDown(false),
	anchor(0),
	selStart(0),
	selEnd(0),
	fRunner(NULL)
{
	BMessage message(_PING_);
	fRunner = new (nothrow) BMessageRunner(messenger, &message, 300000);
}


_BTextTrackState_::~_BTextTrackState_()
{
	delete fRunner;
}


void
_BTextTrackState_::SimulateMouseMovement(BTextView *textView)
{
	BPoint where;
	ulong 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);
}