//
// tjpzoom 2005.11.29 - 2005.12.02.
// details/usage: http://valid.tjp.hu/zoom/
//
var zoomw = 160;
var zoomh = 120;
var defzoomamount = 2;

var zoomamountstep = 1.2;
var zoomsizemin = 1000;
var zoomsizemax = 100000;
var zoomsizestep = 1.2;
var zoomamountmin = 1;
var zoomamountmax = 12;


var zoomamount = defzoomamount;
var objw;
var objh;
var zoomid = '';
var zoomratio = zoomw / zoomh;
var ieox = 0;
var ieoy = 0;
var ffox = 0;
var ffoy = 0;

function zoom_set(evt) {
    //alert('zoom_set');
    var evt = evt ? evt : window.event ? window.event : null;
    if (!evt) {
        return;
    }
    if (zoomid == '' || parseInt(document.getElementById(zoomid + '_container').style.width) == 0) {
        return true;
    }
    if (evt.keyCode == 37 || evt.keyCode == 100) {
        zoomw /= zoomsizestep;
        zoomh /= zoomsizestep;
        if (zoomw * zoomh < zoomsizemin) {
            zoomh = Math.sqrt(zoomsizemin / zoomratio);
            zoomw = zoomh * zoomratio;
        }
        zoom_init();
        zoom_move();
        return;
    } //left
    if (evt.keyCode == 39 || evt.keyCode == 102) {
        zoomw *= zoomsizestep;
        zoomh *= zoomsizestep;
        if (zoomw * zoomh > zoomsizemax) {
            zoomh = Math.sqrt(zoomsizemax / zoomratio);
            zoomw = zoomh * zoomratio;
        }
        if (zoomw > objw) {
            zoomw = objw;
            zoomh = objw / zoomratio;
        }
        else if (zoomh > objh) {
            zoomh = objh;
            zoomw = objh * zoomratio
        }
        zoom_init();
        zoom_move();
        return;
    } //right
    if (evt.keyCode == 40 || evt.keyCode == 98) {
        zoomamount /= zoomamountstep;
        if (zoomamount < zoomamountmin) {
            zoomamount = zoomamountmin;
        }
        zoom_init();
        zoom_move();
        return;
    } //down
    if (evt.keyCode == 38 || evt.keyCode == 104) {
        zoomamount *= zoomamountstep;
        if (zoomamount > zoomamountmax) {
            zoomamount = zoomamountmax;
        }
        zoom_init();
        zoom_move();
        return;
    } //up
    return;
}

function zoom_init() {
    document.getElementById(zoomid + '_clip').style.width = objw * zoomamount + 'px';
    document.getElementById(zoomid + '_clip').style.height = objh * zoomamount + 'px';
    setTimeout("document.getElementById('" + zoomid + "_trigger').focus();", 0);
}

function zoom_move(evt) {
    if (typeof(evt) == 'object') {
        var evt = evt ? evt : window.event ? window.event : null;
        if (!evt) {
            return;
        }
        if (evt.pageX) {
            xx = evt.pageX - ffox;
            yy = evt.pageY - ffoy;
        } else {
            if (typeof(document.getElementById(zoomid) + 1) == 'number') {
                return true;
            } //mert az ie egy ocska kurva
            //   xx=evt.x - ieox;
            //   yy=evt.y - ieoy;
            xx = evt.clientX - ieox;
            yy = evt.clientY - ieoy;
        }
    } else {
        xx = lastxx;
        yy = lastyy;
    }
    lastxx = xx;
    lastyy = yy;
    if( !document.getElementById(zoomid + '_clip') ) {
        //zoom_on();
        alert('here');
    }
    document.getElementById(zoomid + '_clip').style.margin = ((yy - zoomh / 2 > 0) ? (zoomh / 2 - yy * zoomamount) : (yy * (1 - zoomamount))) + 'px 0px 0px ' + ((xx - zoomw / 2 > 0) ? (zoomw / 2 - xx * zoomamount) : (xx * (1 - zoomamount))) + 'px';
    document.getElementById(zoomid + '_container').style.margin = ((yy - zoomh / 2 > 0) ? (yy - zoomh / 2) : (0)) + 'px 0px 0px ' + ((xx - zoomw / 2 > 0) ? (xx - zoomw / 2) : (0)) + 'px';

    w2 = ((xx + zoomw / 2 < objw) ? ((zoomw / 2 < xx) ? (zoomw) : (zoomw / 2 + xx)) : (zoomw / 2 + objw - xx));
    if (w2 < 0) {
        w2 = 0;
    }
    document.getElementById(zoomid + '_container').style.width = w2 + 'px';
    h2 = ((yy + zoomh / 2 < objh) ? ((zoomh / 2 < yy) ? (zoomh) : (zoomh / 2 + yy)) : (zoomh / 2 + objh - yy));
    if (h2 < 0) {
        h2 = 0;
    }
    document.getElementById(zoomid + '_container').style.height = h2 + 'px';
    return false;
}

function zoom_off() {
    if (zoomid != '') {
        //alert( 'zoom_off' );
        if( document.getElementById(zoomid + '_container') ) {
            document.getElementById(zoomid + '_container').style.width = '0px';
            document.getElementById(zoomid + '_container').style.height = '0px';
        }
    }
    //zoomid = '';
}

function countoffset() {
    ieox = 0;
    ieoy = 0;
    for (zmi = 0; zmi < 50; zmi++) {
        zme = 'document.getElementById(zoomid)';
        for (zmj = 1; zmj <= zmi; zmj++) {
            zme += '.offsetParent';
        }
        if (eval(zme) + 1 == 1) {
            zmi = 100
        } else {
            ieox += eval(zme + '.offsetLeft');
            ieoy += eval(zme + '.offsetTop');
        }
    }
    ffox = ieox;
    ffoy = ieoy;
    if (document.documentElement && document.documentElement.scrollTop) {
        ieox -= document.documentElement.scrollLeft;
        ieoy -= document.documentElement.scrollTop;
    } else {
        ieox -= document.body.scrollLeft;
        ieoy -= document.body.scrollTop;
    }
}

function zoom_on(evt, ow, oh, lowres, highres) {   
    var thisid = String(lowres) + String(highres) + String(ow) + String(oh);
    thisid = 'zoom_' + thisid.replace(/[^a-z0-9]/ig, '')
    if (zoomid == thisid) {
        return;
    }
    if (typeof(highres) == typeof(nemistudom)) {
        highres = lowres;
    }
    var evt = evt ? evt : window.event ? window.event : null;
    if (!evt) {
        return;
    }
    zoomamount = defzoomamount;
    objw = ow;
    objh = oh;
    zoomid = thisid;
    if (evt.pageX) {
        evt.target.parentNode.id = thisid;
        countoffset();
        lastxx = evt.pageX - ffox; //mert a ff egy ocska kurva
        lastyy = evt.pageY - ffoy;
    } else {
        evt.srcElement.parentNode.id = thisid;
        countoffset();
        //  lastxx=evt.x - ieox; //mert az ie egy ocska kurva
        //  lastyy=evt.y - ieoy;
        lastxx = evt.clientX - ieox;
        lastyy = evt.clientY - ieoy;
    }
    
    document.getElementById(thisid).style.width = ow + 'px';
    document.getElementById(thisid).style.height = oh + 'px';
    /**
    * edited by Rick Robinson
    * removed innerHTML and wrote code to 
    * add proper elements to the dom. This
    * seemed to fix the FF3 issue of losing
    * the magnifier
    */
    //document.getElementById(thisid).innerHTML = '<div style="position:absolute; overflow:hidden; width:0; height:0;" id="' + thisid + '_container" onmousemove="zoom_move(event);" onmouseout="zoom_off()"><img src="' + highres + '" alt="" id="' + thisid + '_clip" style="padding:0;margin:0;border:0;" /></div><img src="' + lowres + '" id="' + thisid + '_pic" alt="" style="padding:0;margin:0;border:0;width:' + ow + 'px; height: ' + oh + 'px"/><input type="text" id="' + thisid + '_trigger"  style="width:0;height:0;border:0;margin:0; padding:0;overflow:hidden;"/>';
    var el_image = document.getElementById(thisid);
    zoom_removeChildrenFromNode( el_image );
    var el_zoom_div = document.createElement('div');
    el_zoom_div.style.position = 'absolute';
    el_zoom_div.style.overflow = 'hidden';
    el_zoom_div.style.width = 0;
    el_zoom_div.style.height = 0;
    el_zoom_div.setAttribute('id', thisid + '_container' );
    el_zoom_div.setAttribute('onmousemove', "zoom_move(event);" );
    el_zoom_div.setAttribute('onmouseout', "zoom_off();" );
    
    var el_zoom_image_high_res = document.createElement('img');
    el_zoom_image_high_res.setAttribute('src', highres );
    el_zoom_image_high_res.setAttribute('id', thisid + '_clip');
    el_zoom_image_high_res.style.padding = 0;
    el_zoom_image_high_res.style.margin = 0;
    el_zoom_image_high_res.style.border = 0;
    
    el_zoom_div.appendChild( el_zoom_image_high_res );
    el_image.appendChild( el_zoom_div );
    
    var el_zoom_image_low_res = document.createElement('img');
    el_zoom_image_low_res.setAttribute('src', lowres );
    el_zoom_image_low_res.setAttribute('id', thisid + '_pic');
    el_zoom_image_low_res.style.padding = 0;
    el_zoom_image_low_res.style.margin = 0;
    el_zoom_image_low_res.style.border = 0;
    el_zoom_image_low_res.style.width = ow + 'px';
    el_zoom_image_low_res.style.height = oh + 'px';
    
    el_image.appendChild( el_zoom_image_low_res );
    
    var el_input = document.createElement('input');
    el_input.setAttribute('type', 'text' );
    el_input.setAttribute('id', thisid + '_trigger' );
    el_input.style.padding = 0;
    el_input.style.margin = 0;
    el_input.style.border = 0;
    el_input.style.width = 0;
    el_input.style.height = 0;
    el_input.style.overflow = "hidden";
     
    el_image.appendChild( el_input ); 

    if (zoomw > objw) {
        zoomw = objw;
        zoomh = objw / zoomratio;
    }
    else if (zoomh > objh) {
        zoomh = objh;
        zoomw = objh * zoomratio
    }
    zoom_init();
    zoom_move('');
    if (document.all) {
        document.onkeydown = zoom_set;
    } else {
        //window.captureEvents(Event.KEYDOWN);  
        window.addEventListener( "keydown", zoom_set, true ); 
        //window.onkeydown = zoom_set;
    }
    return false;
}

function zoom_removeChildrenFromNode(node) {
    var i = 0;
    if( node == "undefined" || node == null ) { return; }
    for( i = 0; i < node.childNodes.length; i++ ) {
        node.removeChild( node.childNodes[i] );
    }
}