/* 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 "teenagent/font.h"
#include "teenagent/resources.h"

namespace TeenAgent {

Font::Font() : grid_color(0xd0), shadow_color(0), height(0), width_pack(0), data(0) {
}

void Font::load(int id) {
	delete[] data;
	data = NULL;

	Common::SeekableReadStream *s = Resources::instance()->varia.getStream(id);
	if (s == NULL)
		error("loading font %d failed", id);

	data = new byte[s->size()];
	s->read(data, s->size());
	debug(0, "font size: %d", s->size());
}

uint Font::render(Graphics::Surface *surface, int x, int y, char c, byte color) {
	unsigned idx = (unsigned char)c;
	if (idx < 0x20 || idx >= 0x81) {
		debug(0, "unhandled char 0x%02x", idx);
		return 0;
	}
	idx -= 0x20;
	byte *glyph = data + READ_LE_UINT16(data + idx * 2);

	uint h = glyph[0], w = glyph[1];
	if (surface == NULL || surface->pixels == NULL)
		return w - width_pack;

	//debug(0, "char %c, width: %dx%d", c, w, h);
	glyph += 2;
	byte *dst = (byte *)surface->getBasePtr(x, y);
	for (uint i = 0; i < h; ++i) {
		for (uint j = 0; j < w; ++j) {
			byte v = *glyph++;
			switch (v) {
			case 0:
				break;
			case 1:
				dst[j] = shadow_color;
				break;
			case 2:
				dst[j] = color;
				break;
			default:
				dst[j] = v;
			}
		}
		dst += surface->pitch;
	}
	return w - width_pack;
}

static uint find_in_str(const Common::String &str, char c, uint pos = 0) {
	while (pos < str.size() && str[pos] != c) ++pos;
	return pos;
}

uint Font::render(Graphics::Surface *surface, int x, int y, const Common::String &str, byte color, bool show_grid) {
	if (surface != NULL) {
		uint max_w = render(NULL, 0, 0, str, false);
		if (show_grid)
			grid(surface, x - 4, y - 2, max_w + 8, 8 + 6, grid_color);

		uint i = 0, j;
		do {
			j = find_in_str(str, '\n', i);
			Common::String line(str.c_str() + i, j - i);
			//debug(0, "line: %s", line.c_str());

			uint w = render(NULL, 0, 0, line, false);
			int xp = x + (max_w - w) / 2;
			for (uint k = 0; k < line.size(); ++k) {
				xp += render(surface, xp, y, line[k], color);
			}

			y += height;
			i = j + 1;
		} while (i < str.size());
		return max_w;
	} else {
		//surface == NULL;
		uint w = 0, max_w = 0;
		for (uint i = 0; i < str.size(); ++i) {
			char c = str[i];
			if (c == '\n') {
				y += height;
				if (w > max_w)
					max_w = w;
				w = 0;
				continue;
			}
			w += render(NULL, 0, 0, c, color);
		}
		if (w > max_w)
			max_w = w;

		return max_w;
	}
}

void Font::grid(Graphics::Surface *surface, int x, int y, int w, int h, byte color) {
	byte *dst = (byte *)surface->getBasePtr(x, y);
	for (int i = 0; i < h; ++i) {
		for (int j = 0; j < w; ++j) {
			if (((i ^ j) & 1) == 0)
				dst[j] = color;
		}
		dst += surface->pitch;
	}
}

Font::~Font() {
	delete[] data;
}

} // End of namespace TeenAgent