/* 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 2
 * 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

#include "backends/vkeybd/virtual-keyboard-parser.h"

#include "common/keyboard.h"
#include "graphics/imageman.h"
#include "common/util.h"

namespace Common {

VirtualKeyboardParser::VirtualKeyboardParser(VirtualKeyboard *kbd) : XMLParser() {
	_keyboard = kbd;
	
	_callbacks["keyboard"] = &VirtualKeyboardParser::parserCallback_Keyboard;
	_callbacks["mode"]     = &VirtualKeyboardParser::parserCallback_Mode;
	_callbacks["event"]    = &VirtualKeyboardParser::parserCallback_Event;
	_callbacks["layout"]   = &VirtualKeyboardParser::parserCallback_Layout;
	_callbacks["map"]	   = &VirtualKeyboardParser::parserCallback_Map;
	_callbacks["area"]     = &VirtualKeyboardParser::parserCallback_Area;

	_closedCallbacks["keyboard"] = &VirtualKeyboardParser::parserCallback_KeyboardClosed;
	_closedCallbacks["mode"]     = &VirtualKeyboardParser::parserCallback_ModeClosed;
}

void VirtualKeyboardParser::cleanup() {
	_mode = 0;
	_kbdParsed = false;
	_initialModeName.clear();
	if (_parseMode == kParseFull) {
		// reset keyboard to remove existing config
		_keyboard->reset();
	}
}

bool VirtualKeyboardParser::keyCallback(String keyName) {
	if (!_callbacks.contains(_activeKey.top()->name))
		return parserError("%s is not a valid key name.", keyName.c_str());

	return (this->*(_callbacks[_activeKey.top()->name]))();
}

bool VirtualKeyboardParser::closedKeyCallback(String keyName) {
	if (!_closedCallbacks.contains(_activeKey.top()->name))
		return true;
	
	return (this->*(_closedCallbacks[_activeKey.top()->name]))();
}

bool VirtualKeyboardParser::parserCallback_Keyboard() {
	ParserNode *kbdNode = getActiveNode();

	assert(kbdNode->name == "keyboard");

	if (getParentNode(kbdNode) != 0)
		return parserError("Keyboard element must be root");

	if (_kbdParsed)
		return parserError("Only a single keyboard element is allowed");

	// if not full parse then we're done
	if (_parseMode == kParseCheckResolutions)
		return true;

	if (!kbdNode->values.contains("initial_mode"))
		return parserError("Keyboard element must contain initial_mode attribute");

	_initialModeName = kbdNode->values["initial_mode"];

	if (kbdNode->values.contains("h_align")) {
		String h = kbdNode->values["h_align"];
		if (h == "left")
			_keyboard->_hAlignment = VirtualKeyboard::kAlignLeft;
		else if (h == "centre" || h == "center")
			_keyboard->_hAlignment = VirtualKeyboard::kAlignCentre;
		else if (h == "right")
			_keyboard->_hAlignment = VirtualKeyboard::kAlignRight;
	}

	if (kbdNode->values.contains("v_align")) {
		String v = kbdNode->values["h_align"];
		if (v == "top")
			_keyboard->_vAlignment = VirtualKeyboard::kAlignTop;
		else if (v == "middle" || v == "center")
			_keyboard->_vAlignment = VirtualKeyboard::kAlignMiddle;
		else if (v == "bottom")
			_keyboard->_vAlignment = VirtualKeyboard::kAlignBottom;
	}

	return true;
}

bool VirtualKeyboardParser::parserCallback_KeyboardClosed() {
	_kbdParsed = true;
	if (!_keyboard->_initialMode)
		return parserError("Initial mode of keyboard pack not defined");
	return true;
}

bool VirtualKeyboardParser::parserCallback_Mode() {
	ParserNode *modeNode = getActiveNode();

	assert(modeNode->name == "mode");

	if (getParentNode(modeNode) == 0 || getParentNode(modeNode)->name != "keyboard")
		return parserError("Mode element must be child of keyboard element");

	if (!modeNode->values.contains("name") || !modeNode->values.contains("resolutions"))
		return parserError("Mode element must contain name and resolutions attributes");

	String name = modeNode->values["name"];

	if (_parseMode == kParseFull) {
		// if full parse then add new mode to keyboard

		if (_keyboard->_modes.contains(name))
			return parserError("Mode '%s' has already been defined", name.c_str());

		VirtualKeyboard::Mode mode;
		mode.name = name;
		_keyboard->_modes[name] = mode;
		_mode = &(_keyboard->_modes[name]);

		if (name == _initialModeName)
			_keyboard->_initialMode = _mode;
	} else
		_mode = &(_keyboard->_modes[name]);

	String resolutions = modeNode->values["resolutions"];
	StringTokenizer tok (resolutions, " ,");

	// select best resolution simply by minimising the difference between the 
	// overlay size and the resolution dimensions.
	// TODO: improve this by giving preference to a resolution that is smaller
	// than the overlay res (so the keyboard can't be too big for the screen)
	uint16 scrW = g_system->getOverlayWidth(), scrH = g_system->getOverlayHeight();
	uint32 diff = 0xFFFFFFFF;
	String newResolution;
	for (String res = tok.nextToken(); res.size() > 0; res = tok.nextToken()) {
		int resW, resH;
		if (sscanf(res.c_str(), "%dx%d", &resW, &resH) != 2) {
			return parserError("Invalid resolution specification");
		} else {
			if (resW == scrW && resH == scrH) {
				newResolution = res;
				break;
			} else {
				uint32 newDiff = ABS(scrW - resW) + ABS(scrH - resH);
				if (newDiff < diff) {
					diff = newDiff;
					newResolution = res;
				}
			}
		}
	}

	if (newResolution.empty())
		return parserError("No acceptable resolution was found");

	if (_parseMode == kParseCheckResolutions) {
		if (_mode->resolution == newResolution) {
			modeNode->ignore = true;
			return true;
		} else {
			// remove data relating to old resolution
			ImageMan.unregisterSurface(_mode->bitmapName);
			_mode->bitmapName.clear();
			_mode->image = 0;
			_mode->imageMap.removeAllAreas();
		}
	}

	_mode->resolution = newResolution;
	_layoutParsed = false;

	return true;
}

bool VirtualKeyboardParser::parserCallback_ModeClosed() {
	if (!_layoutParsed) {
		return parserError("'%s' layout missing from '%s' mode", _mode->resolution.c_str(), _mode->name.c_str());
	}
	return true;
}

bool VirtualKeyboardParser::parserCallback_Event() {
	ParserNode *evtNode = getActiveNode();

	assert(evtNode->name == "event");

	if (getParentNode(evtNode) == 0 || getParentNode(evtNode)->name != "mode")
		return parserError("Event element must be child of mode element");

	if (!evtNode->values.contains("name") || !evtNode->values.contains("type"))
		return parserError("Event element must contain name and type attributes");

	assert(_mode);

	// if just checking resolutions we're done
	if (_parseMode == kParseCheckResolutions)
		return true;

	String name = evtNode->values["name"];
	if (_mode->events.contains(name))
		return parserError("Event '%s' has already been defined", name.c_str());

	VirtualKeyboard::Event *evt = new VirtualKeyboard::Event();
	evt->name = name;

	String type = evtNode->values["type"];
	if (type == "key") {
		if (!evtNode->values.contains("code") || !evtNode->values.contains("ascii")) {
			delete evt;
			return parserError("Key event element must contain code and ascii attributes");
		}
		evt->type = VirtualKeyboard::kEventKey;

		KeyState *ks = (KeyState*) malloc(sizeof(KeyState));
		ks->keycode = (KeyCode)atoi(evtNode->values["code"].c_str());
		ks->ascii = atoi(evtNode->values["ascii"].c_str());
		ks->flags = 0;
		if (evtNode->values.contains("modifiers"))
			ks->flags = parseFlags(evtNode->values["modifiers"]);
		evt->data = ks;

	} else if (type == "modifier") {
		if (!evtNode->values.contains("modifiers")) {
			delete evt;
			return parserError("Key modifier element must contain modifier attributes");
		}
		
		evt->type = VirtualKeyboard::kEventModifier;
		byte *flags = (byte*) malloc(sizeof(byte));
		*(flags) = parseFlags(evtNode->values["modifiers"]);
		evt->data = flags;

	} else if (type == "switch_mode") {
		if (!evtNode->values.contains("mode")) {
			delete evt;
			return parserError("Switch mode event element must contain mode attribute");
		}

		evt->type = VirtualKeyboard::kEventSwitchMode;
		String& mode = evtNode->values["mode"];
		char *str = (char*) malloc(sizeof(char) * mode.size() + 1);
		memcpy(str, mode.c_str(), sizeof(char) * mode.size());
		str[mode.size()] = 0;
		evt->data = str;
	} else if (type == "submit") {
		evt->type = VirtualKeyboard::kEventSubmit;
	} else if (type == "cancel") {
		evt->type = VirtualKeyboard::kEventCancel;
	} else if (type == "clear") {
		evt->type = VirtualKeyboard::kEventClear;
	} else if (type == "delete") {
		evt->type = VirtualKeyboard::kEventDelete;
	} else if (type == "move_left") {
		evt->type = VirtualKeyboard::kEventMoveLeft;
	} else if (type == "move_right") {
		evt->type = VirtualKeyboard::kEventMoveRight;
	} else {
		delete evt;
		return parserError("Event type '%s' not known", type.c_str());
	}

	_mode->events[name] = evt;

	return true;
}

bool VirtualKeyboardParser::parserCallback_Layout() {
	ParserNode *layoutNode = getActiveNode();

	assert(layoutNode->name == "layout");

	if (getParentNode(layoutNode) == 0 || getParentNode(layoutNode)->name != "mode")
		return parserError("Layout element must be child of mode element");

	if (!layoutNode->values.contains("resolution") || !layoutNode->values.contains("bitmap"))
		return parserError("Layout element must contain resolution and bitmap attributes");

	assert(!_mode->resolution.empty());

	String res = layoutNode->values["resolution"];

	if (res != _mode->resolution) {
		layoutNode->ignore = true;
		return true;
	}

	_mode->bitmapName = layoutNode->values["bitmap"];
	_mode->image = ImageMan.getSurface(_mode->bitmapName);
	if (!_mode->image) {
		if (!ImageMan.registerSurface(_mode->bitmapName, 0))
			return parserError("Error loading bitmap '%s'", _mode->bitmapName.c_str());

		_mode->image = ImageMan.getSurface(_mode->bitmapName);
		if (!_mode->image)
			return parserError("Error loading bitmap '%s'", _mode->bitmapName.c_str());
	}
	
	if (layoutNode->values.contains("transparent_color")) {
		int r, g, b;
		if (!parseIntegerKey(layoutNode->values["transparent_color"].c_str(), 3, &r, &g, &b))
			return parserError("Could not parse color value");
		_mode->transparentColor = g_system->RGBToColor(r, g, b);
	} else
		_mode->transparentColor = g_system->RGBToColor(255, 0, 255); // default to purple

	if (layoutNode->values.contains("display_font_color")) {
		int r, g, b;
		if (!parseIntegerKey(layoutNode->values["display_font_color"].c_str(), 3, &r, &g, &b))
			return parserError("Could not parse color value");
		_mode->displayFontColor = g_system->RGBToColor(r, g, b);
	} else
		_mode->displayFontColor = g_system->RGBToColor(0, 0, 0); // default to black

	_layoutParsed = true;

	return true;
}

bool VirtualKeyboardParser::parserCallback_Map() {
	ParserNode *mapNode = getActiveNode();

	assert(mapNode->name == "map");

	if (getParentNode(mapNode) == 0 || getParentNode(mapNode)->name != "layout")
		return parserError("Map element must be child of layout element");

	return true;
}

bool VirtualKeyboardParser::parserCallback_Area() {
	ParserNode *areaNode = getActiveNode();

	assert(areaNode->name == "area");

	if (getParentNode(areaNode) == 0 || getParentNode(areaNode)->name != "map")
		return parserError("Area element must be child of map element");
	
	if (!areaNode->values.contains("shape") || !areaNode->values.contains("coords") || !areaNode->values.contains("target"))
		return parserError("Area element must contain shape, coords and target attributes");

	String& shape = areaNode->values["shape"];
	String& target = areaNode->values["target"];
	String& coords = areaNode->values["coords"];

	if (target == "display_area") {
		if (shape != "rect")
			return parserError("display_area must be a rect area");
		_mode->displayArea = new Rect();
		return parseRect(_mode->displayArea, coords);
	} else if (shape == "rect") {
		Polygon *poly = _mode->imageMap.createArea(target);
		return parseRectAsPolygon(poly, coords);
	} else if (shape == "poly") {
		Polygon *poly = _mode->imageMap.createArea(target);
		return parsePolygon(poly, coords);
	}
	return parserError("Area shape '%s' not known", shape.c_str());
}

byte VirtualKeyboardParser::parseFlags(const String& flags) {
	if (flags.empty())
		return 0;

	StringTokenizer tok(flags, ", ");
	byte val = 0;
	for (String fl = tok.nextToken(); !fl.empty(); fl = tok.nextToken()) {
		if (fl == "ctrl" || fl == "control")
			val |= KBD_CTRL;
		else if (fl == "alt")
			val |= KBD_ALT;
		else if (fl == "shift")
			val |= KBD_SHIFT;
	}
	return val;
}

bool VirtualKeyboardParser::parseRect(Rect *rect, const String& coords) {
	int x1, y1, x2, y2;
	if (!parseIntegerKey(coords.c_str(), 4, &x1, &y1, &x2, &y2))
		return parserError("Invalid coords for rect area");
	rect->left = x1; rect->top = y1; rect->right = x2; rect->bottom = y2;
	if (!rect->isValidRect())
		return parserError("Rect area is not a valid rectangle");
	return true;
}

bool VirtualKeyboardParser::parsePolygon(Polygon *poly, const String& coords) {
	StringTokenizer tok (coords, ", ");
	for (String st = tok.nextToken(); !st.empty(); st = tok.nextToken()) {
		int x, y;
		if (sscanf(st.c_str(), "%d", &x) != 1)
			return parserError("Invalid coords for polygon area");
		st = tok.nextToken();
		if (sscanf(st.c_str(), "%d", &y) != 1)
			return parserError("Invalid coords for polygon area");
		poly->addPoint(x, y);
	}
	if (poly->getPointCount() < 3)
		return parserError("Invalid coords for polygon area");

	return true;
}

bool VirtualKeyboardParser::parseRectAsPolygon(Polygon *poly, const String& coords) {
	Rect rect;
	if (!parseRect(&rect, coords))
		return false;
	poly->addPoint(rect.left, rect.top);
	poly->addPoint(rect.right, rect.top);
	poly->addPoint(rect.right, rect.bottom);
	poly->addPoint(rect.left, rect.bottom);
	return true;
}

} // end of namespace GUI