/*
 * MojoMagnify 0.1.7 - JavaScript Image Magnifier
 * Copyright (c) 2008 Jacob Seidelin, cupboy@gmail.com, http://blog.nihilogic.dk/
 * Licensed under the MPL License [http://www.nihilogic.dk/licenses/mpl-license.txt]
 */


var MojoMagnify = (function() {

    var $ = function(id) {return document.getElementById(id);};
    var dc = function(tag) {return document.createElement(tag);};

    var isIE = !!document.all && !!window.attachEvent && !window.opera;

    function addEvent(element, ev, handler)
    {
        var doHandler = function(e) {
            return handler(e||window.event);
        }
        if (element.addEventListener) {
            element.addEventListener(ev, doHandler, false);
        } else if (element.attachEvent) {
            element.attachEvent("on" + ev, doHandler);
        }
    }

    function getElementPos(element)
    {
        var x = element.offsetLeft;
        var y = element.offsetTop;
        var parent = element.offsetParent;
        while (parent) {
            x += parent.offsetLeft;
            y += parent.offsetTop;
            parent = parent.offsetParent;
        }
        return {
            x : x,
            y : y
        }
    }

    function getEventMousePos(element, e) {
        var scrollX = document.body.scrollLeft || document.documentElement.scrollLeft;
        var scrollY = document.body.scrollTop || document.documentElement.scrollTop;

        if (e.currentTarget) {
            var pos = getElementPos(element);
            return {
                x : e.clientX - pos.x + scrollX,
                y : e.clientY - pos.y + scrollY
            }
        }
        return {
            x : e.offsetX,
            y : e.offsetY
        }
    }

    function setZoomPos(img, x, y, pos) {
        var zoomImg = img.__mojoMagnifyImage;
        if (!zoomImg) return;

        var full = img.__mojoMagnifyOptions.full;

        img.__mojoMagnifyX = x;
        img.__mojoMagnifyY = y;
        img.__mojoMagnifyPos = pos;

        var zoom = img.__mojoMagnifyZoomer;

        var maskWidth = zoom.offsetWidth;
        var maskHeight = zoom.offsetHeight;

        var imgLeft = img.offsetLeft;
        var imgTop = img.offsetTop;
        var w = img.offsetWidth;
        var h = img.offsetHeight;


        if (full) {
            var fx = x / img.offsetWidth;
            var fy = y / img.offsetHeight;

            var dw = maskWidth - img.offsetWidth;
            var dh = maskHeight - img.offsetHeight;

            var left = -dw * fx;
            var top = -dh * fy;
        } else {
            var left = pos.x - maskWidth/2;
            var top = pos.y - maskHeight/2;

            if (!isIE) {
                left -= imgLeft;
                top -= imgTop;
            }
        }

        zoom.style.left = left + "px";
        zoom.style.top = top + "px";

        if (full) {
            var zx = 0;
            var zy = 0;
        } else {
            var zoomXRatio = zoomImg.offsetWidth / w;
            var zoomYRatio = zoomImg.offsetHeight / h;

            var zoomX = Math.round(x * zoomXRatio);
            var zoomY = Math.round(y * zoomYRatio);

            var zx = -zoomX + maskWidth/2;
            var zy = -zoomY + maskHeight/2;
        }

        zoomImg.style.left = zx + "px";
        zoomImg.style.top = zy + "px";
    }

    function startAnimation(img) {
        var options = img.__mojoMagnifyOptions;

        if (img.__mojoMagnifyAnimTimer)
            clearTimeout(img.__mojoMagnifyAnimTimer);
        var step = 1;

        var zoom = img.__mojoMagnifyZoomer;
        var zoomImg = img.__mojoMagnifyImage;
        var zoomBorder = img.__mojoMagnifyBorder;

        var imgWidth = img.offsetWidth;
        var imgHeight = img.offsetHeight;

        var dw = img.__mojoMagnifyWidth - imgWidth;
        var dh = img.__mojoMagnifyHeight - imgHeight;

        var next = function() {
            var w = imgWidth + dw * (step/10);
            var h = imgHeight + dh * (step/10);

            zoomBorder.style.width = w + "px";
            zoomBorder.style.height = h + "px";
            zoom.style.width = w + "px";
            zoom.style.height = h + "px";
            zoomImg.style.width = w + "px";
            zoomImg.style.height = h + "px";

            if (img.__mojoMagnifyPos) {
                setZoomPos(img, img.__mojoMagnifyX, img.__mojoMagnifyY, img.__mojoMagnifyPos);
            }

            if (step < 10) {

                step += 1;
                img.__mojoMagnifyAnimTimer = setTimeout(next, 60);
            } else {
                img.__mojoMagnifyAnimTimer = 0;
            }
        }
        next();
    }

    function makeMagnifiable(img, zoomSrc, opt) {
        var options = opt || {};

        img.__mojoMagnifyOptions = options;

        // make sure the image is loaded, if not then add an onload event and return
        if (!img.complete && !img.__mojoMagnifyQueued) {
            addEvent(img, "load", function() {
                img.__mojoMagnifyQueued = true;
                setTimeout(function() {
                    makeMagnifiable(img, zoomSrc);
                }, 1);
            });
            return;
        }
        var w = img.offsetWidth;
        var h = img.offsetHeight;

        var oldParent = img.parentNode;

        if (oldParent.nodeName.toLowerCase() != "a") {
            var linkParent = dc("a");
            linkParent.setAttribute("href", zoomSrc);
            oldParent.replaceChild(linkParent, img);
            linkParent.appendChild(img);
        } else {
            var linkParent = oldParent;
        }

        linkParent.style.position = "relative";
        linkParent.style.display = "block";
        linkParent.style.width = w+"px";
        linkParent.style.height = h+"px";

        var imgLeft = img.offsetLeft;
        var imgTop = img.offsetTop;

        var zoom = dc("div");
        zoom.className = "mojomagnify_zoom";
        zoom.style.left = "-9999px";

        var parent = img.parentNode;
        var zoomImg = dc("img");
        zoomImg.className = "mojomagnify_img";
        zoomImg.style.position = "absolute";

        if (isIE) {
            // IE won't let the mouse click pass through properly to the link,
            // so we clone the link and use it for the zoom image as well. Do for all browsers, perhaps?
            var zoomLink = dc("a");
            zoomLink.setAttribute("href", linkParent.getAttribute("href"));
            zoomLink.setAttribute("onclick", linkParent.getAttribute("onclick"));
            zoomLink.style.position = "absolute";
            zoomLink.style.left = "0px";
            zoomLink.style.top = "0px";
            zoomLink.appendChild(zoomImg);
            zoom.appendChild(zoomLink);
        } else {
            zoom.appendChild(zoomImg);
        }

        var ctr = dc("div");
        with (ctr.style) {
            position = "absolute";
            left = imgLeft+"px";
            top = imgTop+"px";
            width = w+"px";
            height = h+"px";
            overflow = "hidden";
            display = "block";
        }


        ctr.appendChild(zoom);
        parent.appendChild(ctr);

        var zoomBorder = dc("div");
        zoomBorder.className = "mojomagnify_border";
        zoom.appendChild(zoomBorder);

        var zoomInput = parent;

        // clear old overlay
        if (img.__mojoMagnifyOverlay)
            parent.removeChild(img.__mojoMagnifyOverlay);
        img.__mojoMagnifyOverlay = ctr;

        // clear old high-res image
        if (img.__mojoMagnifyImage && img.__mojoMagnifyImage.parentNode)
            img.__mojoMagnifyImage.parentNode.removeChild(img.__mojoMagnifyImage);

        img.__mojoMagnifyImage = zoomImg;
        img.__mojoMagnifyZoomer = zoom;
        img.__mojoMagnifyBorder = zoomBorder;

        var isInImage = false;

        addEvent(zoomImg, "load", function() {

            var onMouseOut = function(e) {
                var target = e.target || e.srcElement;
                if (!target) return;
                if (target.nodeName != "DIV") return;
                var relTarget = e.relatedTarget || e.toElement;
                if (!relTarget) return;
                while (relTarget != target && relTarget.nodeName != "BODY" && relTarget.parentNode) {
                    relTarget = relTarget.parentNode;
                }
                if (relTarget != target) {
                    isInImage = false;
                    ctr.style.display = "none";
                }
            };

            addEvent(ctr, "mouseout", onMouseOut);
            addEvent(ctr, "mouseleave", onMouseOut);
            if (isIE) {
                addEvent(document.body, "mouseover",
                    function(e) {
                        if (isInImage && e.toElement != zoomImg) {
                            ctr.style.display = "none";
                        }
                    }
                );
            }

            addEvent(zoomInput, "mousemove",
                function(e) {
                    if (!isInImage) {
                        if (options.animate) {
                            startAnimation(img);
                        }
                    }
                    isInImage = true;

                    ctr.style.display = "block";

                    var pos = getEventMousePos(zoomInput, e);

                    if (e.srcElement && isIE) {
                        if (e.srcElement == zoom) return;
                        if (e.srcElement != zoomInput) {
                            var zoomImgPos = getElementPos(e.srcElement);
                            var imgPos = getElementPos(img);
                            pos.x -= (imgPos.x - zoomImgPos.x);
                            pos.y -= (imgPos.y - zoomImgPos.y);
                        }
                    }

                    var x = e.clientX - (getElementPos(img).x - (document.body.scrollLeft||document.documentElement.scrollLeft));
                    var y = e.clientY - (getElementPos(img).y - (document.body.scrollTop||document.documentElement.scrollTop));

                    setZoomPos(img, x, y, pos);
                }
            );

            if (options.full) {
                var maskWidth = zoomImg.offsetWidth;
                var maskHeight = zoomImg.offsetHeight;
                img.__mojoMagnifyWidth = maskWidth;
                img.__mojoMagnifyHeight = maskHeight;
                zoomBorder.style.width = maskWidth + "px";
                zoomBorder.style.height = maskHeight + "px";
                zoom.style.width = maskWidth + "px";
                zoom.style.height = maskHeight + "px";
            }

            ctr.style.display = "none";
        });

        // I've no idea. Simply setting the src will make IE screw it self into a 100% CPU fest. In a timeout, it's ok.
        setTimeout(function() {
            zoomImg.src = zoomSrc;
        }, 1);
    }

    function setCoords(img, x, y) {
        if (!img.__mojoMagnifyOverlay) return;
        isInImage = true;
        img.__mojoMagnifyOverlay.style.display = "block";
        setZoomPos(img, x, y, { x : x, y : y });
    }

    function init() {
        //alert('MM init.');
        var images = document.getElementsByTagName("img");
        var imgList = [];
        for (var i=0;i<images.length;i++) {
            imgList.push(images[i]);
        }
        for (var i=0;i<imgList.length;i++) {
            var img = imgList[i];
            var zoomSrc = img.getAttribute("data-magnifysrc");
            if (zoomSrc) {
                var opt = {
                    full : img.getAttribute("data-magnifyfull") === "true",
                    animate : img.getAttribute("data-magnifyanimate") === "true"
                };
                makeMagnifiable(img, zoomSrc, opt);
            }
        }
    }

    return {
        addEvent : addEvent,
        init : init,
        makeMagnifiable : makeMagnifiable,
        setCoords : setCoords
    };

})();

//MojoMagnify.addEvent(window, "load", MojoMagnify.init);