/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "common/system.h"
#include "common/unicode-bidi.h"
#include "common/translation.h"

#include "graphics/macgui/mactext.h"
#include "graphics/macgui/macfontmanager.h"

#include "gui/gui-manager.h"

#include "gui/ThemeEngine.h"
#include "gui/ThemeEval.h"

#include "gui/widgets/richtext.h"
#include "gui/widgets/scrollbar.h"
#include "gui/animation/FluidScroll.h"

namespace GUI {

const Graphics::TTFMap ttfFamily[] = {
	{"NotoSans-Regular.ttf", Graphics::kMacFontRegular},
	{"NotoSans-Bold.ttf", Graphics::kMacFontBold},
	{"NotoSerif-Italic.ttf", Graphics::kMacFontItalic},
	{"NotoSerif-Bold-Italic.ttf", Graphics::kMacFontBold | Graphics::kMacFontItalic},
	{nullptr, 0}
};

RichTextWidget::RichTextWidget(GuiObject *boss, int x, int y, int w, int h, bool scale, const Common::U32String &text, const Common::U32String &tooltip)
	: Widget(boss, x, y, w, h, scale, tooltip), CommandSender(nullptr)  {

	_text = text;

	init();
}

RichTextWidget::RichTextWidget(GuiObject *boss, int x, int y, int w, int h, const Common::U32String &text, const Common::U32String &tooltip)
	: RichTextWidget(boss, x, y, w, h, false, text, tooltip) {
}

RichTextWidget::RichTextWidget(GuiObject *boss, const Common::String &name, const Common::U32String &text, const Common::U32String &tooltip)
	: Widget(boss, name, tooltip), CommandSender(nullptr)  {

	_text = text;

	init();
}

void RichTextWidget::init() {
	setFlags(WIDGET_ENABLED | WIDGET_CLEARBG | WIDGET_TRACK_MOUSE | WIDGET_DYN_TOOLTIP | WIDGET_WANT_TICKLE | WIDGET_RETAIN_FOCUS);

	_type = kRichTextWidget;

	_verticalScroll = new ScrollBarWidget(this, _w - 16, 0, 16, _h);
	_verticalScroll->setTarget(this);
	_scrolledX = 0;
	_scrolledY = 0;

	_innerMargin = g_gui.xmlEval()->getVar("Globals.RichTextWidget.InnerMargin", 0);
	_scrollbarWidth = g_gui.xmlEval()->getVar("Globals.Scrollbar.Width", 0);

	_textWidth = MAX(1, _w - _scrollbarWidth - 2 * _innerMargin);
	_textHeight = MAX(1, _h - 2 * _innerMargin);

	_limitH = 140;

	_scrollPos = 0.0f;
	_fluidScroller = new FluidScroller();
	_isDragging = false;
}


RichTextWidget::~RichTextWidget() {
	delete _txtWnd;

	if (_surface)
		_surface->free();
	delete _surface;

	if (_cachedTextSurface)
		_cachedTextSurface->free();
	delete _cachedTextSurface;
	delete _fluidScroller;
}

void RichTextWidget::handleMouseWheel(int x, int y, int direction) {
	_fluidScroller->handleMouseWheel(direction);
	applyScrollPos();
}

void RichTextWidget::handleMouseDown(int x, int y, int button, int clickCount) {
	_mouseDownY = _mouseDownStartY = y;
	_fluidScroller->stopAnimation();
}

void RichTextWidget::handleMouseUp(int x, int y, int button, int clickCount) {
	if (_isDragging)
		_fluidScroller->startFling();

	// Allow some tiny finger slipping
	if (ABS(_mouseDownY - _mouseDownStartY) > 5 || _isDragging) {
		_mouseDownY = _mouseDownStartY = 0;
		_isDragging = false;

		return;
	}

	_mouseDownY = _mouseDownStartY = 0;
	_isDragging = false;

	if (!_txtWnd)
		return;

	Common::String link = _txtWnd->getMouseLink(x - _innerMargin + _scrolledX, y - _innerMargin + _scrolledY).encode();

	if (link.hasPrefixIgnoreCase("http"))
		g_system->openUrl(link);
}

void RichTextWidget::handleMouseMoved(int x, int y, int button) {
	if (_txtWnd) {
		Common::String link = _txtWnd->getMouseLink(x - _innerMargin + _scrolledX, y - _innerMargin + _scrolledY).encode();

		if (!link.empty() && link.hasPrefixIgnoreCase("http"))
			g_gui.theme()->setActiveCursor(GUI::ThemeEngine::kCursorIndex);
		else
			g_gui.theme()->setActiveCursor(GUI::ThemeEngine::kCursorNormal);
	}

	if (_mouseDownStartY == 0 || _mouseDownY == y || !_txtWnd)
		return;

	int deltaY = _mouseDownY - y;

	if (!_isDragging && ABS(deltaY) > 5)
		_isDragging = true;

	if (_isDragging) {
		_mouseDownY = y;
		if (deltaY != 0) {
			_fluidScroller->feedDrag(g_system->getMillis(), deltaY);
			applyScrollPos();
		}
	}
}

void RichTextWidget::handleTickle() {
	if (_fluidScroller->update(g_system->getMillis(), _scrollPos))
		applyScrollPos();
}

void RichTextWidget::applyScrollPos() {
	_scrollPos = _fluidScroller->getVisualPosition();
	_scrolledY = (int)_scrollPos;
	int maxScroll = MAX(0, _txtWnd->getTextHeight() - _limitH);
	_verticalScroll->_currentPos = CLIP((int)_scrolledY, 0, (int)maxScroll);
	_verticalScroll->recalc();
	markAsDirty();
}

void RichTextWidget::handleTooltipUpdate(int x, int y) {
	if (!_txtWnd)
		return;

	_tooltip = _txtWnd->getMouseLink(x - _innerMargin + _scrolledX, y - _innerMargin + _scrolledY);
}

void RichTextWidget::handleCommand(CommandSender *sender, uint32 cmd, uint32 data) {
	Widget::handleCommand(sender, cmd, data);
	switch (cmd) {
	case kSetPositionCmd:
		_scrolledY = _verticalScroll->_currentPos;
		_scrollPos = _scrolledY;
		_fluidScroller->stopAnimation();
		_scrollPos = _fluidScroller->setPosition(_scrollPos, false);
		reflowLayout();
		g_gui.scheduleTopDialogRedraw();
		break;
	default:
		break;
	}
}

void RichTextWidget::recalc() {
	_innerMargin = g_gui.xmlEval()->getVar("Globals.RichTextWidget.InnerMargin", 0);
	_scrollbarWidth = g_gui.xmlEval()->getVar("Globals.Scrollbar.Width", 0);
	_textWidth = MAX(1, _w - _scrollbarWidth - 2 * _innerMargin);
	_textHeight = MAX(1, _h - 2 * _innerMargin);
	_limitH = _textHeight;

	// Workaround: Currently Graphics::MacText::setMaxWidth does not work well.
	// There is a known limitation that the size is skipped when the text contains table,
	// and there is also an issue with the font.
	// So for now we recreate the widget.
//	if (_txtWnd) {
//		_txtWnd->setMaxWidth(_textWidth);
//		if (_surface->w != _textWidth || _surface->h != _textHeight)
//			_surface->create(_textWidth, _textHeight, g_gui.getWM()->_pixelformat);
//	} else {
//		createWidget();
//	}

	if (!_surface || _surface->w != _textWidth) {
		if (_surface) {
			_surface->free();
			delete _surface;
			_surface = nullptr;
		}
		delete _txtWnd;
		_txtWnd = nullptr;
		if (_cachedTextSurface) {
			_cachedTextSurface->free();
			delete _cachedTextSurface;
			_cachedTextSurface = nullptr;
		}
	} else if (_surface->h != _textHeight) {
		_surface->create(_textWidth, _textHeight, g_gui.getWM()->_pixelformat);

		int h = _txtWnd->getTextHeight();
		int maxScroll = MAX(0, h - _limitH);
		_verticalScroll->_numEntries = h;
		_verticalScroll->_currentPos = CLIP((int)_scrolledY, 0, (int)maxScroll);
		_verticalScroll->_entriesPerPage = _limitH;
		_verticalScroll->_singleStep = _h / 4;
		_verticalScroll->setPos(_w - _scrollbarWidth, 0);
		_verticalScroll->setSize(_scrollbarWidth, _h - 1);
		_verticalScroll->setVisible(_verticalScroll->_numEntries > _limitH); //show when there is something to scroll
		_verticalScroll->recalc();
		_fluidScroller->setBounds((float)maxScroll, (float)_limitH, (float)_verticalScroll->_singleStep);
	}
}

void RichTextWidget::createWidget() {
	Graphics::MacWindowManager *wm = g_gui.getWM();

	uint8 bgR, bgG, bgB;
	uint32 bg;
	if (g_gui.theme()->getDrawDataColor(kDDWidgetBackgroundDefault, bgR, bgG, bgB))
		bg = wm->_pixelformat.ARGBToColor(255, bgR, bgG, bgB);
	else
		bg = wm->_pixelformat.ARGBToColor(0xFF, 0xFF, 0xFF, 0xFF);

	TextColorData *normal = g_gui.theme()->getTextColorData(kTextColorNormal);
	uint32 fg = wm->_pixelformat.RGBToColor(normal->r, normal->g, normal->b);

	const int fontHeight = g_gui.xmlEval()->getVar("Globals.Font.Height", 25);

	int newId;
	bool useTTF = false; // For English we use MacFONTs

#ifdef USE_TRANSLATION
	// MacFONTs do not contain diacritic marks or non-English characters, so we have to use TTF instead
	if (TransMan.getCurrentLanguage() != "en")
		useTTF = true;
#endif

	if (useTTF)
		newId = wm->_fontMan->registerTTFFont(ttfFamily);
	else
		newId = Graphics::kMacFontNewYork;

#ifdef USE_FREETYPE2
		// Use anti-aliased (light) rendering for the GUI help text.
		Graphics::TTFRenderMode prevRenderMode = wm->_fontMan->getTTFRenderMode();
		wm->_fontMan->setTTFRenderMode(Graphics::kTTFRenderModeLight);
#endif

	Graphics::MacFont macFont(newId, fontHeight, Graphics::kMacFontRegular);
	_txtWnd = new Graphics::MacText(Common::U32String(), wm, &macFont, fg, bg, _textWidth, Graphics::kTextAlignLeft);

	if (!_imageArchive.empty())
		_txtWnd->setImageArchive(_imageArchive);

	_txtWnd->setMarkdownText(_text);

#ifdef USE_FREETYPE2
	// Restore previous render mode now that all fonts have been loaded
	wm->_fontMan->setTTFRenderMode(prevRenderMode);
#endif

	int textHeight = _txtWnd->getTextHeight();

	if (textHeight > 0) {
		if (!_cachedTextSurface || _cachedTextSurface->w != _textWidth || _cachedTextSurface->h != textHeight) {
			if (_cachedTextSurface) {
				_cachedTextSurface->free();
				delete _cachedTextSurface;
			}
			_cachedTextSurface = new Graphics::ManagedSurface(_textWidth, textHeight, wm->_pixelformat);
		}
		_cachedTextSurface->clear(bg);
		_txtWnd->draw(_cachedTextSurface, 0, 0, _textWidth, textHeight, 0, 0);
	}

	if (!_surface || _surface->w != _textWidth || _surface->h != _textHeight) {
    	if (_surface)
        	_surface->create(_textWidth, _textHeight, wm->_pixelformat);
    	else
        	_surface = new Graphics::ManagedSurface(_textWidth, _textHeight, wm->_pixelformat);
	}

	int h = _txtWnd->getTextHeight();
	int maxScroll = MAX(0, h - _limitH);
	_verticalScroll->_numEntries = h;
	_verticalScroll->_currentPos = CLIP((int)_scrolledY, 0, (int)maxScroll);
	_verticalScroll->_entriesPerPage = _limitH;
	_verticalScroll->_singleStep = _h / 4;
	_verticalScroll->setPos(_w - _scrollbarWidth, 0);
	_verticalScroll->setSize(_scrollbarWidth, _h - 1);
	_verticalScroll->setVisible(_verticalScroll->_numEntries > _limitH); //show when there is something to scroll
	_verticalScroll->recalc();
	_fluidScroller->setBounds((float)maxScroll, (float)_limitH, (float)_verticalScroll->_singleStep);
}

void RichTextWidget::reflowLayout() {
	Widget::reflowLayout();

	recalc();
}

void RichTextWidget::ensureWidget() {
	if (_txtWnd)
		return;
	createWidget();
}

void RichTextWidget::drawWidget() {
	ensureWidget();

	if (!_txtWnd)
		recalc();

	g_gui.theme()->drawWidgetBackground(Common::Rect(_x, _y, _x + _w, _y + _h), ThemeEngine::kWidgetBackgroundPlain);

	uint8 bgR, bgG, bgB;
	uint32 bg;
	if (g_gui.theme()->getDrawDataColor(kDDWidgetBackgroundDefault, bgR, bgG, bgB))
		bg = g_gui.getWM()->_pixelformat.ARGBToColor(255, bgR, bgG, bgB);
	else
		bg = g_gui.getWM()->_pixelformat.ARGBToColor(0xFF, 0xFF, 0xFF, 0xFF);

	_surface->clear(bg);

	if (_cachedTextSurface) {
		int cachedHeight = _cachedTextSurface->h;
		int srcY = _scrolledY < 0 ? 0 : (int)_scrolledY;
		int destY = _scrolledY < 0 ? -(int)_scrolledY : 0;

		if (srcY < cachedHeight)
			_surface->simpleBlitFrom(*_cachedTextSurface, Common::Rect(0, srcY, _textWidth,
			MIN(srcY + _textHeight - destY, cachedHeight)), Common::Point(0, destY));
	} else
		_txtWnd->draw(_surface, 0, _scrolledY, _textWidth, _textHeight, 0, 0);

	g_gui.theme()->drawManagedSurface(Common::Point(_x + _innerMargin, _y + _innerMargin), *_surface, Graphics::ALPHA_OPAQUE);
}

void RichTextWidget::draw() {
	Widget::draw();

	if (_verticalScroll->isVisible()) {
		_verticalScroll->draw();
	}
}

void RichTextWidget::markAsDirty() {
	Widget::markAsDirty();

	if (_verticalScroll->isVisible()) {
		_verticalScroll->markAsDirty();
	}
}

bool RichTextWidget::containsWidget(Widget *w) const {
	if (w == _verticalScroll || _verticalScroll->containsWidget(w))
		return true;
	return false;
}

Widget *RichTextWidget::findWidget(int x, int y) {
	if (_verticalScroll->isVisible() && x >= _w - _scrollbarWidth)
		return _verticalScroll;

	return this;
}

} // End of namespace GUI