/*

JatoBAS - A javascript MSX-BASIC translator
Copyright (C) 2006  Rafael Jannone

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library 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
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

Read the LGPL license at: 
http://www.gnu.org/copyleft/lesser.txt

Contact the author -
email: rafael AT jannone DOT org

*/

function SpriteCanvas() {
	this.init();
}

SpriteCanvas.prototype.init = function() {	
	this.palette = new Array(16);	
	this.setPalette(0,0,0,0);
	this.setPalette(1,0,0,0);
	this.setPalette(2,33,200,66);
	this.setPalette(3,94,220,120);
	this.setPalette(4,84,85,237);
	this.setPalette(5,125,118,252);
	this.setPalette(6,212,82,77);
	this.setPalette(7,66,235,245);
	this.setPalette(8,252,85,84);
	this.setPalette(9,255,121,120);
	this.setPalette(10,212,193,84);
	this.setPalette(11,230,206,128);
	this.setPalette(12,33,176,59);
	this.setPalette(13,201,91,186);
	this.setPalette(14,204,204,204);
	this.setPalette(15,255,255,255);

	this.changed = true;

	this.sprites = {};
	this.spriteData = {};
	
	var canvas = document.createElement('canvas');
	canvas.width = 256 * 2;
	canvas.height = 192 * 2;
	this.canvasCtx = canvas.getContext("2d");	
	this.el = this.canvas = canvas;
}

SpriteCanvas.prototype.appendTo = function(parent) {
	parent = parent || document.body;
	parent.appendChild(this.el);
}

SpriteCanvas.prototype.setMode = function(mode) {
	this.mode = mode;
	this.changed = true;
	this.sprites = {};
	this.spriteData = {};
}

SpriteCanvas.prototype.setPalette = function(color, r, g, b) {
	this.palette[color] = 'rgba(' + [r,g,b,255].join(',') + ')';
}

SpriteCanvas.prototype.setSprite = function(idx, data) {
	this.spriteData[idx] = data;
	this.changed = true;
}

SpriteCanvas.prototype.putSprite = function(idx, x, y, c, pat) {
	this.sprites[idx] = {x: x, y: y, c: (c || 0), pat: (pat || 0)};
	this.changed = true;	
}

SpriteCanvas.prototype.update = function() {
	if (!this.changed)
		return;
		
	var cv = this.canvasCtx;
	cv.clearRect(0,0, 512, 384);
	for (var i in this.sprites) {
		var sp = this.sprites[i];
		if (sp && sp.c)
			this.drawSprite(sp);
	}
	this.changed = false;	
}

SpriteCanvas.prototype.drawSprite = function(sp) {
	var cv = this.canvasCtx;
	var data = this.spriteData[sp.pat] || "";
	
	var x = sp.x * 2;
	var y = sp.y * 2;
	
	cv.fillStyle = this.palette[sp.c];
	for (var i=0; i < data.length; i++, y += 2) {
		var mask = data.charCodeAt(i);
		if (i == 16) {
			x += 16;
			y -= 32;
		}
		if (mask & 128) cv.fillRect( x+0, y, 2, 2);
		if (mask &  64) cv.fillRect( x+2, y, 2, 2);
		if (mask &  32) cv.fillRect( x+4, y, 2, 2);
		if (mask &  16) cv.fillRect( x+6, y, 2, 2);
		if (mask &   8) cv.fillRect( x+8, y, 2, 2);
		if (mask &   4) cv.fillRect(x+10, y, 2, 2);
		if (mask &   2) cv.fillRect(x+12, y, 2, 2);
		if (mask &   1) cv.fillRect(x+14, y, 2, 2);		
	}
}