/*
 * Copyright 2005-2010, Axel Dörfler, axeld@pinc-software.de.
 * Copyright 2009-2010, Adrien Destugues <pulkomandy@gmail.com>.
 * All rights reserved. Distributed under the terms of the MIT License.
 */


#include "Locale.h"
#include "LocaleWindow.h"
#include "LanguageListView.h"

#include <iostream>

#include <Alert.h>
#include <Application.h>
#include <Button.h>
#include <Catalog.h>
#include <ControlLook.h>
#include <GroupLayout.h>
#include <LayoutBuilder.h>
#include <Locale.h>
#include <LocaleRoster.h>
#include <Screen.h>
#include <ScrollView.h>
#include <StringView.h>
#include <TabView.h>
#include <UnicodeChar.h>

#include "FormatSettingsView.h"


#undef B_TRANSLATE_CONTEXT
#define B_TRANSLATE_CONTEXT "Locale Preflet Window"


static const uint32 kMsgLanguageInvoked = 'LaIv';
static const uint32 kMsgLanguageDragged = 'LaDr';
static const uint32 kMsgPreferredLanguageInvoked = 'PLIv';
static const uint32 kMsgPreferredLanguageDragged = 'PLDr';
static const uint32 kMsgPreferredLanguageDeleted = 'PLDl';
static const uint32 kMsgCountrySelection = 'csel';
static const uint32 kMsgDefaults = 'dflt';

static const uint32 kMsgPreferredLanguagesChanged = 'lang';


static int
compare_typed_list_items(const BListItem* _a, const BListItem* _b)
{
	static BCollator collator;

	LanguageListItem* a = (LanguageListItem*)_a;
	LanguageListItem* b = (LanguageListItem*)_b;

	return collator.Compare(a->Text(), b->Text());
}


static int
compare_void_list_items(const void* _a, const void* _b)
{
	static BCollator collator;

	LanguageListItem* a = *(LanguageListItem**)_a;
	LanguageListItem* b = *(LanguageListItem**)_b;

	return collator.Compare(a->Text(), b->Text());
}


// #pragma mark -


LocaleWindow::LocaleWindow()
	:
	BWindow(BRect(0, 0, 0, 0), "Locale", B_TITLED_WINDOW, B_QUIT_ON_WINDOW_CLOSE
		| B_ASYNCHRONOUS_CONTROLS | B_AUTO_UPDATE_SIZE_LIMITS)
{
	BLocale defaultLocale;
	be_locale_roster->GetDefaultLocale(&defaultLocale);

	SetLayout(new BGroupLayout(B_HORIZONTAL));

	float spacing = be_control_look->DefaultItemSpacing();

	BTabView* tabView = new BTabView("tabview");
	BGroupView* languageTab = new BGroupView(B_TRANSLATE("Language"),
		B_HORIZONTAL, spacing);

	// first list: available languages
	fLanguageListView = new LanguageListView("available",
		B_MULTIPLE_SELECTION_LIST);
	BScrollView* scrollView = new BScrollView("scroller", fLanguageListView,
		B_WILL_DRAW | B_FRAME_EVENTS, false, true);

	fLanguageListView->SetInvocationMessage(new BMessage(kMsgLanguageInvoked));
	fLanguageListView->SetDragMessage(new BMessage(kMsgLanguageDragged));

	// Fill the language list from the LocaleRoster data
	BMessage installedLanguages;
	if (be_locale_roster->GetInstalledLanguages(&installedLanguages) == B_OK) {
		BString currentID;
		LanguageListItem* lastAddedCountryItem = NULL;

		for (int i = 0; installedLanguages.FindString("langs", i, &currentID)
				== B_OK; i++) {
			// Now get an human-readable, localized name for each language
			BLanguage* currentLanguage;
			be_locale_roster->GetLanguage(currentID.String(),
				&currentLanguage);

			BString name;
			currentLanguage->GetName(name);

			// TODO: as long as the app_server doesn't support font overlays,
			// use the translated name if problematic characters are used...
			const char* string = name.String();
			while (uint32 code = BUnicodeChar::FromUTF8(&string)) {
				if (code > 1424) {
					currentLanguage->GetTranslatedName(name);
					break;
				}
			}

			LanguageListItem* item = new LanguageListItem(name,
				currentID.String(), currentLanguage->Code());
			if (currentLanguage->IsCountrySpecific()
				&& lastAddedCountryItem != NULL
				&& lastAddedCountryItem->Code() == item->Code()) {
				fLanguageListView->AddUnder(item, lastAddedCountryItem);
			} else {
				// This is a language variant, add it at top-level
				fLanguageListView->AddItem(item);
				if (!currentLanguage->IsCountrySpecific()) {
					item->SetExpanded(false);
					lastAddedCountryItem = item;
				}
			}

			delete currentLanguage;
		}

		fLanguageListView->FullListSortItems(compare_typed_list_items);
	} else {
		BAlert* alert = new BAlert("Error",
			B_TRANSLATE("Unable to find the available languages! You can't "
				"use this preflet!"),
			B_TRANSLATE("OK"), NULL, NULL,
			B_WIDTH_AS_USUAL, B_OFFSET_SPACING, B_STOP_ALERT);
		alert->Go();
	}

	// Second list: active languages
	fPreferredListView = new LanguageListView("preferred",
		B_MULTIPLE_SELECTION_LIST);
	BScrollView* scrollViewEnabled = new BScrollView("scroller",
		fPreferredListView, B_WILL_DRAW | B_FRAME_EVENTS, false, true);

	fPreferredListView->SetInvocationMessage(
		new BMessage(kMsgPreferredLanguageInvoked));
	fPreferredListView->SetDeleteMessage(
		new BMessage(kMsgPreferredLanguageDeleted));
	fPreferredListView->SetDragMessage(
		new BMessage(kMsgPreferredLanguageDragged));

	BLayoutBuilder::Group<>(languageTab)
		.AddGroup(B_VERTICAL, spacing)
			.Add(new BStringView("", B_TRANSLATE("Available languages")))
			.Add(scrollView)
			.End()
		.AddGroup(B_VERTICAL, spacing)
			.Add(new BStringView("", B_TRANSLATE("Preferred languages")))
			.Add(scrollViewEnabled)
			.End()
		.SetInsets(spacing, spacing, spacing, spacing);

	BView* countryTab = new BView(B_TRANSLATE("Country"), B_WILL_DRAW);
	countryTab->SetLayout(new BGroupLayout(B_VERTICAL, 0));

	BListView* listView = new BListView("country", B_SINGLE_SELECTION_LIST);
	scrollView = new BScrollView("scroller", listView,
		B_WILL_DRAW | B_FRAME_EVENTS, false, true);
	listView->SetSelectionMessage(new BMessage(kMsgCountrySelection));

	// get all available countries
	BMessage countryList;
	be_locale_roster->GetInstalledLanguages(&countryList);
	BString countryCode;

	LanguageListItem* currentItem = NULL;
	for (int i = 0; countryList.FindString("langs", i, &countryCode) == B_OK;
			i++) {
		BLocale locale(countryCode);
		BString countryName;

		locale.GetName(countryName);

		LanguageListItem* item
			= new LanguageListItem(countryName, countryCode,
				NULL);
		listView->AddItem(item);
		if (!strcmp(countryCode, defaultLocale.Code()))
			currentItem = item;
	}

	listView->SortItems(compare_void_list_items);
	if (currentItem != NULL)
		listView->Select(listView->IndexOf(currentItem));

	// TODO: find a real solution intead of this hack
	listView->SetExplicitMinSize(
		BSize(25 * be_plain_font->Size(), B_SIZE_UNSET));

	fFormatView = new FormatView(defaultLocale);

	countryTab->AddChild(BLayoutBuilder::Group<>(B_HORIZONTAL, spacing)
		.AddGroup(B_VERTICAL, 3)
			.Add(scrollView)
			.End()
		.Add(fFormatView)
		.SetInsets(spacing, spacing, spacing, spacing));

	listView->ScrollToSelection();

	tabView->AddTab(languageTab);
	tabView->AddTab(countryTab);

	BButton* button = new BButton(B_TRANSLATE("Defaults"),
		new BMessage(kMsgDefaults));

	fRevertButton = new BButton(B_TRANSLATE("Revert"),
		new BMessage(kMsgRevert));
	fRevertButton->SetEnabled(false);

	BLayoutBuilder::Group<>(this, B_VERTICAL, spacing)
		.Add(tabView)
		.AddGroup(B_HORIZONTAL, spacing)
			.Add(button)
			.Add(fRevertButton)
			.AddGlue()
			.End()
		.SetInsets(spacing, spacing, spacing, spacing)
		.End();

	_UpdatePreferredFromLocaleRoster();
	SettingsReverted();
	CenterOnScreen();
}


LocaleWindow::~LocaleWindow()
{
}


void
LocaleWindow::MessageReceived(BMessage* message)
{
	switch (message->what) {
		case kMsgDefaults:
			_Defaults();
			break;

		case kMsgRevert:
			be_app_messenger.SendMessage(message);
			_UpdatePreferredFromLocaleRoster();
			break;

		case kMsgLanguageDragged:
		{
			void* target = NULL;
			if (message->FindPointer("drop_target", &target) != B_OK
				|| target != fPreferredListView)
				break;

			// Add from available languages to preferred languages
			int32 dropIndex;
			if (message->FindInt32("drop_index", &dropIndex) != B_OK)
				dropIndex = fPreferredListView->CountItems();

			int32 index = 0;
			for (int32 i = 0; message->FindInt32("index", i, &index) == B_OK;
					i++) {
				LanguageListItem* item = static_cast<LanguageListItem*>(
					fLanguageListView->FullListItemAt(index));
				_InsertPreferredLanguage(item, dropIndex++);
			}
			break;
		}
		case kMsgLanguageInvoked:
		{
			int32 index = 0;
			for (int32 i = 0; message->FindInt32("index", i, &index) == B_OK;
					i++) {
				LanguageListItem* item = static_cast<LanguageListItem*>(
					fLanguageListView->ItemAt(index));
				_InsertPreferredLanguage(item);
			}
			break;
		}

		case kMsgPreferredLanguageDragged:
		{
			void* target = NULL;
			if (fPreferredListView->CountItems() == 1
				|| message->FindPointer("drop_target", &target) != B_OK)
				break;

			if (target == fPreferredListView) {
				// change ordering
				int32 dropIndex = message->FindInt32("drop_index");
				int32 index = 0;
				if (message->FindInt32("index", &index) == B_OK
					&& dropIndex != index) {
					BListItem* item = fPreferredListView->RemoveItem(index);
					if (dropIndex > index)
						index--;
					fPreferredListView->AddItem(item, dropIndex);

					_PreferredLanguagesChanged();
				}
				break;
			}

			// supposed to fall through - remove item
		}
		case kMsgPreferredLanguageDeleted:
		case kMsgPreferredLanguageInvoked:
		{
			if (fPreferredListView->CountItems() == 1)
				break;

			// Remove from preferred languages
			int32 index = 0;
			if (message->FindInt32("index", &index) == B_OK) {
				delete fPreferredListView->RemoveItem(index);
				_PreferredLanguagesChanged();

				if (message->what == kMsgPreferredLanguageDeleted)
					fPreferredListView->Select(index);
			}
			break;
		}

		case kMsgCountrySelection:
		{
			// Country selection changed.
			// Get the new selected country from the ListView and send it to the
			// main app event handler.
			void* listView;
			if (message->FindPointer("source", &listView) != B_OK)
				break;

			BListView* countryList = static_cast<BListView*>(listView);

			LanguageListItem* item = static_cast<LanguageListItem*>
				(countryList->ItemAt(countryList->CurrentSelection()));
			BMessage newMessage(kMsgSettingsChanged);
			newMessage.AddString("country", item->ID());
			be_app_messenger.SendMessage(&newMessage);
			SettingsChanged();

			BLocale locale(item->ID());
			fFormatView->SetLocale(locale);
			break;
		}

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


bool
LocaleWindow::QuitRequested()
{
	return true;
}


void
LocaleWindow::SettingsChanged()
{
	fRevertButton->SetEnabled(true);
}


void
LocaleWindow::SettingsReverted()
{
	fRevertButton->SetEnabled(false);
}


void
LocaleWindow::_PreferredLanguagesChanged()
{
	BMessage update(kMsgSettingsChanged);
	int index = 0;
	while (index < fPreferredListView->FullListCountItems()) {
		// only include subitems: we can guess the superitem
		// from them anyway
		LanguageListItem* item = static_cast<LanguageListItem*>(
			fPreferredListView->FullListItemAt(index));
		if (item != NULL)
			update.AddString("language", item->ID());

		index++;
	}
	be_app_messenger.SendMessage(&update);

	_EnableDisableLanguages();
}


void
LocaleWindow::_EnableDisableLanguages()
{
	DisableUpdates();

	for (int32 i = 0; i < fLanguageListView->FullListCountItems(); i++) {
		LanguageListItem* item = static_cast<LanguageListItem*>(
			fLanguageListView->FullListItemAt(i));

		bool enable = fPreferredListView->ItemForLanguageID(item->ID()) == NULL;
		if (item->IsEnabled() != enable) {
			item->SetEnabled(enable);

			int32 visibleIndex = fLanguageListView->IndexOf(item);
			if (visibleIndex >= 0) {
				if (!enable)
					fLanguageListView->Deselect(visibleIndex);
				fLanguageListView->InvalidateItem(visibleIndex);
			}
		}
	}

	SettingsChanged();

	EnableUpdates();
}


//! Get the preferred languages from the settings.
void
LocaleWindow::_UpdatePreferredFromLocaleRoster()
{
	DisableUpdates();

	// Delete all existing items
	for (int32 index = fPreferredListView->CountItems(); index-- > 0; ) {
		delete fPreferredListView->ItemAt(index);
	}
	fPreferredListView->MakeEmpty();

	// Add new ones from the locale roster
	BMessage preferredLanguages;
	be_locale_roster->GetPreferredLanguages(&preferredLanguages);

	BString languageID;
	for (int32 index = 0; preferredLanguages.FindString("language", index,
			&languageID) == B_OK; index++) {
		int32 listIndex;
		LanguageListItem* item
			= fLanguageListView->ItemForLanguageID(languageID.String(),
				&listIndex);
		if (item != NULL) {
			// We found the item we were looking for, now copy it to
			// the other list
			fPreferredListView->AddItem(new LanguageListItem(*item));
		}
	}

	_EnableDisableLanguages();
	EnableUpdates();
}


void
LocaleWindow::_InsertPreferredLanguage(LanguageListItem* item, int32 atIndex)
{
	if (item == NULL || fPreferredListView->ItemForLanguageID(
			item->ID().String()) != NULL)
		return;

	if (atIndex == -1)
		atIndex = fPreferredListView->CountItems();

	BLanguage* language = NULL;
	be_locale_roster->GetLanguage(item->Code(), &language);

	LanguageListItem* baseItem = NULL;
	if (language != NULL) {
		baseItem = fPreferredListView->ItemForLanguageCode(language->Code(),
			&atIndex);
		delete language;
	}

	DisableUpdates();

	fPreferredListView->AddItem(new LanguageListItem(*item), atIndex);

	// Replace other languages with the same base

	if (baseItem != NULL) {
		fPreferredListView->RemoveItem(baseItem);
		delete baseItem;
	}

	_PreferredLanguagesChanged();

	EnableUpdates();
}


void
LocaleWindow::_Defaults()
{
	BMessage update(kMsgSettingsChanged);
	update.AddString("language", "en");

	be_app_messenger.SendMessage(&update);
	SettingsChanged();
	_UpdatePreferredFromLocaleRoster();
}