/* 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.
 *
 */

#include "hdb/hdb.h"

namespace HDB {

Map::Map() {
	_mapLoaded = false;
}

int Map::loadTiles() {

	int tile, temp;
	int skyIndex = 0;

	// Load all tiles
	for (uint j = 0; j < _height; j++) {
		for (uint i = 0; i < _width; i++) {
			tile = _background[j * _width + i];
			if ((temp = g_hdb->_drawMan->isSky(tile)) && !skyIndex) {
				skyIndex = temp;
			}
			g_hdb->_drawMan->getTile(tile);
			g_hdb->_drawMan->getTile(_foreground[j * _width + i]);
		}
	}

	return skyIndex;
}

bool Map::load(Common::SeekableReadStream *stream) {
	if (_mapLoaded) {
		return false;
	}

	debug(5, "map stream size: %d(%x)", stream->size(), stream->size());

	// Load MSM data header
	stream->read(_name, 32);
	_width = stream->readUint16LE();
	_height = stream->readUint16LE();
	_backgroundOffset = stream->readUint32LE();
	_foregroundOffset = stream->readUint32LE();
	_iconNum = stream->readUint16LE();
	_infoNum = stream->readUint16LE();            // not used in the original
	_iconListOffset = stream->readUint32LE();
	_infoListOffset = stream->readUint32LE();     // not used in the original

	debug(5, "map: w: %d(%x), h: %d(%x) bg: %x fg: %x icon#: %d(%x) icon: %x info#: %d(%x) info: %x",
			_width, _width, _height, _height, _backgroundOffset, _foregroundOffset, _iconNum, _iconNum,
			_iconListOffset, _infoNum, _infoNum, _infoListOffset);

	// Reading Background
	_background = new uint16[_width * _height];
	stream->seek(_backgroundOffset);
	for (int i = 0; i < _width * _height; i++) {
		_background[i] = stream->readUint16LE();
	}
	if (gDebugLevel >= 5) {
		debug(5, "Background:");
		Common::hexdump((const byte *)_background, 512);
	}


	// Reading Foreground
	_foreground = new uint16[_width * _height];
	stream->seek(_foregroundOffset);
	for (int i = 0; i < _width * _height; i++) {
		_foreground[i] = stream->readUint16LE();
	}

	if (gDebugLevel >= 5) {
		debug(5, "Foreground:");
		Common::hexdump((const byte *)_foreground, 512);
	}

	// Reading Icon List
	_iconList = new MSMIcon[_iconNum];
	for (uint i = 0; i < _iconNum; i++) {
		_iconList[i].icon = stream->readUint16LE();
		_iconList[i].x = stream->readUint16LE();
		_iconList[i].y = stream->readUint16LE();

		stream->read(_iconList[i].funcInit, 32);
		stream->read(_iconList[i].funcAction, 32);
		stream->read(_iconList[i].funcUse, 32);

		_iconList[i].dir = stream->readUint16LE();
		_iconList[i].level = stream->readUint16LE();
		_iconList[i].value1 = stream->readUint16LE();
		_iconList[i].value2 = stream->readUint16LE();
	}

	/*
		TODO: Add the InfoList when it comes up
	*/

	/*
		TODO: Set the InMapName once its setup
	*/

	_mapExplosions = new byte[_width * _height];
	_mapExpBarrels = new byte[_width * _height];
	_mapLaserBeams = new byte[_width * _height];

	int sky = loadTiles();
	g_hdb->_drawMan->setSky(sky);
	//_mapX = _mapY = 0;
	_mapX = 50 * kTileWidth;
	_mapY = 30 * kTileHeight;

	/*
		TODO: Add the animating tile lists
	*/

	_mapLoaded = true;

	return true;
}

void Map::draw() {
	if (!_mapLoaded) {
		return;
	}

	int matrixY;
	int screenX, screenY;
	int maxTileX, maxTileY;

	// Calculate Tile Offsets and Panning Offsets
	_mapTileX = _mapX / kTileWidth;
	_mapTileY = _mapY / kTileHeight;
	_mapTileXOff = -(_mapX % kTileWidth);
	_mapTileYOff = -(_mapY % kTileHeight);

	matrixY = _mapTileY * _width;
	screenY = _mapTileYOff;

	/*
		Note from Original Source:
		need to set the number of tiles to draw on the screen.  Most of the time
		we need to draw an extra tile because we're displaying a half-tile, but
		sometimes the offset is exactly at 0 and thus we don't need to draw a
		tile offscreen that we'll never see.  In fact, doing this fixes a bug
		that could occur because we would be accessing map data that's outside the map
		when we're at the very bottom of the map.
	*/

	maxTileX = (_mapTileXOff >= -8) ? kScreenXTiles - 1 : kScreenXTiles;
	maxTileY = (!_mapTileYOff) ? kScreenYTiles - 1 : kScreenYTiles;

	if (matrixY + (maxTileY - 1)*_width > _height * _width) {
		return;
	}

	for (int j = 0; j < maxTileY; j++) {
		screenX = _mapTileXOff;
		for (int i = 0; i < maxTileX; i++) {

			// Draw Background Tile
			uint16 tileIndex = _background[matrixY + _mapTileX + i];
			if (tileIndex < 0) {
				tileIndex = 0;
			}

			// Draw if not a sky tile
			if (!g_hdb->_drawMan->isSky(tileIndex)) {
				g_hdb->_drawMan->getTile(tileIndex)->draw(screenX, screenY);
			}

			// Draw Foreground Tile
			tileIndex = _foreground[matrixY + _mapTileX + i];
			if (tileIndex >= 0) {
				Tile *fTile = g_hdb->_drawMan->getTile(tileIndex);
				if (fTile && !(fTile->_flags & kFlagInvisible)) {

					if ((fTile->_flags & kFlagGrating)) {
						/*
						TODO: Implement Gratings Check
						*/
						warning("STUB: Map::draw: Gratings Check not found");
					} else if ((fTile->_flags & kFlagForeground)) {
						/*
						TODO: Implement Gratings Check
						*/
						warning("STUB: Map::draw: Gratings Check not found");
					} else {
						if (fTile->_flags & kFlagMasked) {
							/*
								TODO: Implement MaskedMapTile drawing
							*/
							fTile->drawMasked(screenX, screenY);
						} else {
							fTile->draw(screenX, screenY);
						}
					}
				}
			}

			screenX += kTileWidth;
		}
		matrixY += _width;
		screenY += kTileWidth;
	}

	/*
		TODO: Implement animated Map Tiles
	*/
}

uint16 Map::getMapBGTileIndex(int x, int y) {
	if (x < 0 || x >= _width || y < 0 || y >= _height) {
		return 0;
	}
	return _background[y * _width + x];
}

uint16 Map::getMapFGTileIndex(int x, int y) {
	if (x < 0 || x >= _width || y < 0 || y >= _height) {
		return 0;
	}
	return _foreground[y * _width + x];
}

void Map::getMapXY(int *x, int *y) {
	*x = _mapX;
	*y = _mapY;
}

void Map::setMapXY(int x, int y) {
	if (x < 0) {
		x = 0;
	} else if (x > (_width * kTileWidth - 480)) {
		x = _width * kTileWidth - 480;
	}

	if (y < 0) {
		y = 0;
	} else if (y > (_height * kTileHeight - 480)) {
		y = _height * kTileHeight - 480;
	}

	_mapX = x;
	_mapY = y;
}

// Sets _mapX and _mapY and tries to center the map around X, Y
void Map::centerMapXY(int x, int y) {
	int checkx = x / kTileWidth;
	int checky = y / kTileHeight;

	int minx, miny, maxx, maxy;

	// Scan from centerX to right edge
	maxx = (_width - (16/2)) * kTileWidth;
	for (int i = checkx + 1; i <= checkx + (16 / 2); i++) {
		if (!getMapBGTileIndex(i, checky)) {
			maxx = (i - (16 / 2)) * kTileWidth;
			break;
		}
	}

	// Scan from centerX to left edge
	minx = 0;
	for (int i = checkx - 1; i >= checkx - (16 / 2); i--) {
		if (!getMapBGTileIndex(i, checky)) {
			// +1 because we don't want to see one whole tile
			minx = (1 + i + (16 / 2)) * kTileWidth;
			break;
		}
	}

	// Scan from centerY to bottom edge
	maxy = (_height - (16/2)) * kTileHeight;
	for (int i = checky + 1; i <= checky + (16 / 2); i++) {
		if (!getMapBGTileIndex(checkx, i)) {
			maxy = (i - (16 / 2)) * kTileHeight;
			break;
		}
	}

	// Scan from centerY to top edge
	miny = 0;
	for (int i = checky - 1; i >= checkx - (16 / 2); i--) {
		if (!getMapBGTileIndex(checkx, i)) {
			// +! because we don't want to see one whole tile
			miny = (1 + i + (16 / 2)) * kTileHeight;
			break;
		}
	}

	if (x < minx) {
		x = minx;
	} else if (x > maxx) {
		x = maxx;
	}

	if (y < miny) {
		y = miny;
	} else if (y > maxy) {
		y = maxy;
	}

	x -= (480 / 2);
	y -= (480 / 2);

	setMapXY(x, y);
}

}