/*
* Pixastic Lib - Core Functions - v0.1.3
* Copyright (c) 2008 Jacob Seidelin, jseidelin@nihilogic.dk, http://blog.nihilogic.dk/
* License: [http://www.pixastic.com/lib/license.txt]
*/
var pixastic_parseonload = true;

var Pixastic = (function () {


    function addEvent(el, event, handler) {
        if (el.addEventListener)
            el.addEventListener(event, handler, false);
        else if (el.attachEvent)
            el.attachEvent("on" + event, handler);
    }

    function onready(handler) {
        var handlerDone = false;
        var execHandler = function () {
            if (!handlerDone) {
                handlerDone = true;
                handler();
            }
        }
        document.write("<" + "script defer src=\"//:\" id=\"__onload_ie_pixastic__\"></" + "script>");
        var script = document.getElementById("__onload_ie_pixastic__");
        script.onreadystatechange = function () {
            if (script.readyState == "complete") {
                script.parentNode.removeChild(script);
                execHandler();
            }
        }
        if (document.addEventListener)
            document.addEventListener("DOMContentLoaded", execHandler, false);
        addEvent(window, "load", execHandler);
    }

    function init() {
        var imgEls = getElementsByClass("pixastic", null, "img");
        var canvasEls = getElementsByClass("pixastic", null, "canvas");
        var elements = imgEls.concat(canvasEls);
        for (var i = 0; i < elements.length; i++) {
            (function () {

                var el = elements[i];
                var actions = [];
                var classes = el.className.split(" ");
                for (var c = 0; c < classes.length; c++) {
                    var cls = classes[c];
                    if (cls.substring(0, 9) == "pixastic-") {
                        var actionName = cls.substring(9);
                        if (actionName != "")
                            actions.push(actionName);
                    }
                }
                if (actions.length) {
                    if (el.tagName.toLowerCase() == "img") {
                        var dataImg = new Image();
                        dataImg.src = el.src;
                        if (dataImg.complete) {
                            for (var a = 0; a < actions.length; a++) {
                                var res = Pixastic.applyAction(el, el, actions[a], null);
                                if (res)
                                    el = res;
                            }
                        } else {
                            dataImg.onload = function () {
                                for (var a = 0; a < actions.length; a++) {
                                    var res = Pixastic.applyAction(el, el, actions[a], null)
                                    if (res)
                                        el = res;
                                }
                            }
                        }
                    } else {
                        setTimeout(function () {
                            for (var a = 0; a < actions.length; a++) {
                                var res = Pixastic.applyAction(
								el, el, actions[a], null
							);
                                if (res)
                                    el = res;
                            }
                        }, 1);
                    }
                }

            })();
        }
    }

    if (typeof pixastic_parseonload != "undefined" && pixastic_parseonload)
        onready(init);

    // getElementsByClass by Dustin Diaz, http://www.dustindiaz.com/getelementsbyclass/
    function getElementsByClass(searchClass, node, tag) {
        var classElements = new Array();
        if (node == null)
            node = document;
        if (tag == null)
            tag = '*';

        var els = node.getElementsByTagName(tag);
        var elsLen = els.length;
        var pattern = new RegExp("(^|\\s)" + searchClass + "(\\s|$)");
        for (i = 0, j = 0; i < elsLen; i++) {
            if (pattern.test(els[i].className)) {
                classElements[j] = els[i];
                j++;
            }
        }
        return classElements;
    }

    var debugElement;

    function writeDebug(text, level) {
        if (!Pixastic.debug) return;
        try {
            switch (level) {
                case "warn":
                    console.warn("Pixastic:", text);
                    break;
                case "error":
                    console.error("Pixastic:", text);
                    break;
                default:
                    console.log("Pixastic:", text);
            }
        } catch (e) {
        }
        if (!debugElement) {

        }
    }

    // canvas capability checks

    var hasCanvas = (function () {
        var c = document.createElement("canvas");
        var val = false;
        try {
            val = !!((typeof c.getContext == "function") && c.getContext("2d"));
        } catch (e) { }
        return function () {
            return val;
        }
    })();

    var hasCanvasImageData = (function () {
        var c = document.createElement("canvas");
        var val = false;
        var ctx;
        try {
            if (typeof c.getContext == "function" && (ctx = c.getContext("2d"))) {
                val = (typeof ctx.getImageData == "function");
            }
        } catch (e) { }
        return function () {
            return val;
        }
    })();

    var hasGlobalAlpha = (function () {
        var hasAlpha = false;
        var red = document.createElement("canvas");
        if (hasCanvas() && hasCanvasImageData()) {
            red.width = red.height = 1;
            var redctx = red.getContext("2d");
            redctx.fillStyle = "rgb(255,0,0)";
            redctx.fillRect(0, 0, 1, 1);

            var blue = document.createElement("canvas");
            blue.width = blue.height = 1;
            var bluectx = blue.getContext("2d");
            bluectx.fillStyle = "rgb(0,0,255)";
            bluectx.fillRect(0, 0, 1, 1);

            redctx.globalAlpha = 0.5;
            redctx.drawImage(blue, 0, 0);
            var reddata = redctx.getImageData(0, 0, 1, 1).data;

            hasAlpha = (reddata[2] != 255);
        }
        return function () {
            return hasAlpha;
        }
    })();


    // return public interface

    return {

        parseOnLoad: false,

        debug: false,

        applyAction: function (img, dataImg, actionName, options) {

            options = options || {};

            var imageIsCanvas = (img.tagName.toLowerCase() == "canvas");
            if (imageIsCanvas && Pixastic.Client.isIE()) {
                if (Pixastic.debug) writeDebug("Tried to process a canvas element but browser is IE.");
                return false;
            }

            var canvas, ctx;
            var hasOutputCanvas = false;
            if (Pixastic.Client.hasCanvas()) {
                hasOutputCanvas = !!options.resultCanvas;
                canvas = options.resultCanvas || document.createElement("canvas");
                ctx = canvas.getContext("2d");
            }

            var w = img.offsetWidth;
            var h = img.offsetHeight;

            if (imageIsCanvas) {
                w = img.width;
                h = img.height;
            }

            // offsetWidth/Height might be 0 if the image is not in the document
            if (w == 0 || h == 0) {
                if (img.parentNode == null) {
                    // add the image to the doc (way out left), read its dimensions and remove it again
                    var oldpos = img.style.position;
                    var oldleft = img.style.left;
                    img.style.position = "absolute";
                    img.style.left = "-9999px";
                    document.body.appendChild(img);
                    w = img.offsetWidth;
                    h = img.offsetHeight;
                    document.body.removeChild(img);
                    img.style.position = oldpos;
                    img.style.left = oldleft;
                } else {
                    if (Pixastic.debug) writeDebug("Image has 0 width and/or height.");
                    return;
                }
            }

            if (actionName.indexOf("(") > -1) {
                var tmp = actionName;
                actionName = tmp.substr(0, tmp.indexOf("("));
                var arg = tmp.match(/\((.*?)\)/);
                if (arg[1]) {
                    arg = arg[1].split(";");
                    for (var a = 0; a < arg.length; a++) {
                        thisArg = arg[a].split("=");
                        if (thisArg.length == 2) {
                            if (thisArg[0] == "rect") {
                                var rectVal = thisArg[1].split(",");
                                options[thisArg[0]] = {
                                    left: parseInt(rectVal[0], 10) || 0,
                                    top: parseInt(rectVal[1], 10) || 0,
                                    width: parseInt(rectVal[2], 10) || 0,
                                    height: parseInt(rectVal[3], 10) || 0
                                }
                            } else {
                                options[thisArg[0]] = thisArg[1];
                            }
                        }
                    }
                }
            }

            if (!options.rect) {
                options.rect = {
                    left: 0, top: 0, width: w, height: h
                };
            } else {
                options.rect.left = Math.round(options.rect.left);
                options.rect.top = Math.round(options.rect.top);
                options.rect.width = Math.round(options.rect.width);
                options.rect.height = Math.round(options.rect.height);
            }

            var validAction = false;
            if (Pixastic.Actions[actionName] && typeof Pixastic.Actions[actionName].process == "function") {
                validAction = true;
            }
            if (!validAction) {
                if (Pixastic.debug) writeDebug("Invalid action \"" + actionName + "\". Maybe file not included?");
                return false;
            }
            if (!Pixastic.Actions[actionName].checkSupport()) {
                if (Pixastic.debug) writeDebug("Action \"" + actionName + "\" not supported by this browser.");
                return false;
            }

            if (Pixastic.Client.hasCanvas()) {
                if (canvas !== img) {
                    canvas.width = w;
                    canvas.height = h;
                }
                if (!hasOutputCanvas) {
                    canvas.style.width = w + "px";
                    canvas.style.height = h + "px";
                }
                ctx.drawImage(dataImg, 0, 0, w, h);

                if (!img.__pixastic_org_image) {
                    canvas.__pixastic_org_image = img;
                    canvas.__pixastic_org_width = w;
                    canvas.__pixastic_org_height = h;
                } else {
                    canvas.__pixastic_org_image = img.__pixastic_org_image;
                    canvas.__pixastic_org_width = img.__pixastic_org_width;
                    canvas.__pixastic_org_height = img.__pixastic_org_height;
                }

            } else if (Pixastic.Client.isIE() && typeof img.__pixastic_org_style == "undefined") {
                img.__pixastic_org_style = img.style.cssText;
            }

            var params = {
                image: img,
                canvas: canvas,
                width: w,
                height: h,
                useData: true,
                options: options
            }

            // Ok, let's do it!

            var res = Pixastic.Actions[actionName].process(params);

            if (!res) {
                return false;
            }

            if (Pixastic.Client.hasCanvas()) {
                if (params.useData) {
                    if (Pixastic.Client.hasCanvasImageData()) {
                        canvas.getContext("2d").putImageData(params.canvasData, options.rect.left, options.rect.top);

                        // Opera doesn't seem to update the canvas until we draw something on it, lets draw a 0x0 rectangle.
                        // Is this still so?
                        canvas.getContext("2d").fillRect(0, 0, 0, 0);
                    }
                }

                if (!options.leaveDOM) {
                    // copy properties and stuff from the source image
                    canvas.title = img.title;
                    canvas.imgsrc = img.imgsrc;
                    if (!imageIsCanvas) canvas.alt = img.alt;
                    if (!imageIsCanvas) canvas.imgsrc = img.src;
                    canvas.className = img.className;
                    canvas.style.cssText = img.style.cssText;
                    canvas.name = img.name;
                    canvas.tabIndex = img.tabIndex;
                    canvas.id = img.id;
                    if (img.parentNode && img.parentNode.replaceChild) {
                        img.parentNode.replaceChild(canvas, img);
                    }
                }

                options.resultCanvas = canvas;

                return canvas;
            }

            return img;
        },

        prepareData: function (params, getCopy) {
            var ctx = params.canvas.getContext("2d");
            var rect = params.options.rect;
            var dataDesc = ctx.getImageData(rect.left, rect.top, rect.width, rect.height);
            var data = dataDesc.data;
            if (!getCopy) params.canvasData = dataDesc;
            return data;
        },

        // load the image file
        process: function (img, actionName, options, callback) {
            if (img.tagName.toLowerCase() == "img") {
                var dataImg = new Image();
                dataImg.src = img.src;
                if (dataImg.complete) {
                    var res = Pixastic.applyAction(img, dataImg, actionName, options);
                    if (callback) callback(res);
                    return res;
                } else {
                    dataImg.onload = function () {
                        var res = Pixastic.applyAction(img, dataImg, actionName, options)
                        if (callback) callback(res);
                    }
                }
            }
            if (img.tagName.toLowerCase() == "canvas") {
                var res = Pixastic.applyAction(img, img, actionName, options);
                if (callback) callback(res);
                return res;
            }
        },

        revert: function (img) {
            if (Pixastic.Client.hasCanvas()) {
                if (img.tagName.toLowerCase() == "canvas" && img.__pixastic_org_image) {
                    img.width = img.__pixastic_org_width;
                    img.height = img.__pixastic_org_height;
                    img.getContext("2d").drawImage(img.__pixastic_org_image, 0, 0);

                    if (img.parentNode && img.parentNode.replaceChild) {
                        img.parentNode.replaceChild(img.__pixastic_org_image, img);
                    }

                    return img;
                }
            } else if (Pixastic.Client.isIE()) {
                if (typeof img.__pixastic_org_style != "undefined")
                    img.style.cssText = img.__pixastic_org_style;
            }
        },

        Client: {
            hasCanvas: hasCanvas,
            hasCanvasImageData: hasCanvasImageData,
            hasGlobalAlpha: hasGlobalAlpha,
            isIE: function () {
                return !!document.all && !!window.attachEvent && !window.opera;
            }
        },

        Actions: {}
    }


})();

Pixastic.Actions.desaturate = {

    process: function (params) {
        var useAverage = !!(params.options.average && params.options.average != "false");

        if (Pixastic.Client.hasCanvasImageData()) {
            var data = Pixastic.prepareData(params);
            var rect = params.options.rect;
            var w = rect.width;
            var h = rect.height;

            var p = w * h;
            var pix = p * 4, pix1, pix2;

            if (useAverage) {
                while (p--)
                    data[pix -= 4] = data[pix1 = pix + 1] = data[pix2 = pix + 2] = (data[pix] + data[pix1] + data[pix2]) / 3
            } else {
                while (p--)
                    data[pix -= 4] = data[pix1 = pix + 1] = data[pix2 = pix + 2] = (data[pix] * 0.3 + data[pix1] * 0.59 + data[pix2] * 0.11);
            }
            return true;
        } else if (Pixastic.Client.isIE()) {
            params.image.style.filter += " gray";
            return true;
        }
    },
    checkSupport: function () {
        return (Pixastic.Client.hasCanvasImageData() || Pixastic.Client.isIE());
    }
}