Element.implement({

  pin: function(options) {
    if (!options) options = {};
    if (!options.left) options.left = 0;
    if (!options.top) options.top = 0;
    if (!options.right) options.right = 0;
    if (!options.bottom) options.bottom = 0;
    
    var el = this;
    var resize = function() {
      var sizes = {
        scroll: window.getScroll(),
        scrollSize: window.getScrollSize(),
        size: window.getSize()
      }
      if (Browser.Engine.trident4) {
        el.setStyles({
          'left': sizes.scroll.x + options.left,
          'top': sizes.scroll.y + options.top
        });
      }
      el.setStyles({
        'width': sizes.size.x - (options.left + options.right),
        'height': sizes.size.y - (options.top + options.bottom)
      });
    };
    
    el.setStyles({
      'position': Browser.Engine.trident4 ? 'absolute' : 'fixed',      
      'left': options.left,
      'top': options.top,
      'width': 1,
      'height': 1
    }).store('pin', resize);
    resize();
    
    window.addEvents({
      'resize': resize,
      'scroll': resize      
    });
    
    return this;
  },

  unpin: function(reset) {
    if (reset == null) reset = true;
    
    var resize = this.retrieve('pin', null);
    if (resize) {
      window.removeEvents({
        'resize': resize,
        'scroll': resize      
      });
      this.store('pin', null);
      if (reset) {
        this.setStyles({
          'position': 'static',
          'left': 'auto',
          'top': 'auto'
        });
      }
    }
    
    return this;
  }

});

var ZoomBox = new Class({

  Implements: Options,
  
  Binds: ['open', 'close', 'zoomIn', 'showImage', 'prev', 'next'],

  options: {
    topOffset: 65,
    initWidth: 350,
    initHeight: 350,
    overlayOpacity: 0.8,
    showCaption: false,
    captionMinHeight: 65,
    hideTags: true,
    uncoverableTags: ['object', 'embed']
  },

  initialize: function(options) {
    this.setOptions(options);
    this.current_image = 0;
    this.current_gallery = 0;
    this.galleries = [];
    this.box = null;
    this.overlay = null;
    this.uncoverableTags = [];
    
    this.scrollTop = window.getScroll().y;
    
    this.families = [];
    this.zoombox_a = [];
    
    this.collect();
  },
  
  collect: function() {
    //var families = this.families;
    var families = [];
    var zoombox_a = [];
    this.galleries = [];
    
    this.current_image = 0;
    this.current_gallery = 0;

    // remove old handlers
    this.zoombox_a.each(function(a) {
      a.removeEvent('click', a.retrieve('zoombox'));
    });

    $$('a').each(function(a) {
      // test 'zoombox' and link extension, and collect all zoombox links
      if (a.rel && a.rel.test(/^zoombox/i) && a.href.split('?')[0].test(/\.(gif|jpg|png)$/i)) {
        if (a.rel.length > 7 && !families.contains(a.rel)) families.push(a.rel);
        if (!this.zoombox_a.contains(a)) zoombox_a.push(a);
      }
    }, this);
    
    this.families = families;
    this.zoombox_a = zoombox_a;
    
    // create an array of arras with all galleries
    zoombox_a.each(function(a) {
      if (a.rel.length > 7) {
        families.each(function(f, i) {
          if (a.rel == f) {
            if (!this.galleries[i]) this.galleries[i] = [];
            this.galleries[i].push($(a));
          };
        }, this);
      } else {
        this.galleries.push([$(a)]);
      }
      a.store('zoombox', this.open.bindWithEvent(this, a));
      a.addEvent('click', a.retrieve('zoombox'));
    }, this);
  },
  
  add: function(a) {
    a = $(a);
    if (!a) return;
    // test 'zoombox' and link extension, and collect all zoombox links
    if (a.rel && a.rel.test(/^zoombox/i) && a.href.split('?')[0].test(/\.(gif|jpg|png)$/i)) {
      if (a.rel.length > 7 && !this.families.contains(a.rel)) this.families.push(a.rel);
      if (!this.zoombox_a.contains(a)) {
        this.zoombox_a.push(a);

        if (a.rel.length > 7) {
          this.families.each(function(f, i) {
            if (a.rel == f) {
              if (!this.galleries[i]) this.galleries[i] = [];
              this.galleries[i].push($(a));
            };
          }, this);
        } else {
          this.galleries.push([$(a)]);
        }
        a.store('zoombox', this.open.bindWithEvent(this, a));
        a.addEvent('click', a.retrieve('zoombox'));
      }
    }
  },
  
  open: function(event, a) {
    if (!a) {
      a = event;
    } else {
      event.stop();
    }
    
    if (a && $type(a) == 'element') {
      a.blur();
    }
    
    this.galleries.each(function(gallery, idx) {
      var i = gallery.indexOf(a);
      if (i != -1) {
        this.current_gallery = idx;
        this.current_image = i;
      }
    }.bind(this));
    
    this.build();

    if (this.options.hideTags) {
      this.uncoverableTags = $$(this.options.uncoverableTags);
      if (this.uncoverableTags.length != 0) this.uncoverableTags.each(function(el) { el.style.visibility = 'hidden'; });
    }

    this.scrollTop = window.getScroll().y;

    var wsize = window.getSize();
    this.box.setStyles({
      'left': (wsize.x - this.options.initWidth) / 2,
      'top': this.scrollTop + (wsize.y - this.options.initHeight) / 2,
      'width': this.options.initWidth,
      'height': this.options.initHeight
    });
    this.image_box.setStyles({
      'width': this.options.initWidth,
      'height': this.options.initHeight
    });

    this.prev_img.setStyle('opacity', 0);
    this.prev_btn.setStyle('display', 'none');
    this.next_img.setStyle('opacity', 0);
    this.next_btn.setStyle('display', 'none');
    //this.close_btn.setStyle('opacity', 0);

    this.overlay.setStyles({
      'display': 'block',
      'opacity': 0
    });
    this.overlay.set('tween', {}).tween('opacity', this.options.overlayOpacity).pin();
    
    if (this.caption) {
      var caption_display = this.caption.retrieve('caption-display', null);
      if (!caption_display) {
        this.caption.store('caption-display', this.caption.getStyle('display'));
      }
      this.caption.setStyles({
        'display': 'none'
      });
    }
    
    this.load(a);
    
    $(document.body).addEvent('keyescape', this.close);
  },

  load: function(a) {
    var url = a.href;
    if (this.options.showCaption) {
      this.image.store('caption', a.title);
      this.captionText = a.title;
    }
    this.image_box.setStyle('visibility', 'hidden').setStyle('opacity', 0.01);
    this.box.setStyle('display', 'block');
    
    if (this.options.showCaption) {
      this.caption.set('tween', {duration: 120}).tween('opacity', 0);
    }
    
    this.prev_img.tween('opacity', 0);
    this.prev_btn.setStyle('display', 'none');
    this.next_img.tween('opacity', 0);
    this.next_btn.setStyle('display', 'none');
    this.image_box.tween('opacity', 0);
    this.box.addClass('zoombox-loading').set('tween', {
      onComplete: function() {
        this.prepareLoad(url);
      }.bind(this)
    }).tween('opacity', 1);
  },
  
  close: function() {
    this.box.set('tween', {
      duration: 300,
      onComplete: function() {
        this.box.setStyle('display', 'none');
      }.bind(this)
    }).tween('opacity', 0);

    this.overlay.unpin(false).set('tween', {
      onComplete: function() {
        this.overlay.setStyle('display', 'none');
        
        if (this.uncoverableTags.length != 0) this.uncoverableTags.each(function(el) { el.style.visibility = 'visible'; });
      }.bind(this)
    }).tween('opacity', 0);
    
    $(document.body).removeEvent('keyescape', this.close);
  },

  prepareLoad: function(url) {
    this.image.src = url;
  },
 
  build: function() {
    if (this.box) return;
    
    if (!this.overlay) {
      this.overlay = new Element('div').
        setStyle('display', 'none').
        addClass('overlay').addClass('zoombox-overlay').
        injectInside(document.body).
        setStyle('cursor', 'pointer').
        addEvent('click', this.close);
    }

    this.box = new Element('div').addClass('zoombox').injectInside(document.body).adopt(
      this.image_box = new Element('div', {'align': 'center'}).addClass('zoombox-image-wrapper').setStyle('overflow', 'hidden').adopt(
        this.image = new Element('img').addEvent('load', this.zoomIn)
      ),
      this.prev_img = new Element('div').addClass('prev_btn').setStyle('opacity', 0),
      this.next_img = new Element('div').addClass('next_btn').setStyle('opacity', 0),
      this.prev_btn = new Element('div').addClass('prev_zone').setStyle('display', 'none').addEvent('click', this.prev).set('html', ' '),
      this.next_btn = new Element('div').addClass('next_zone').setStyle('display', 'none').addEvent('click', this.next).set('html', ' '),
      this.close_btn = new Element('div').addClass('close_btn')./*setStyle('opacity', 0).*/addEvent('click', this.close).set('html', ' ')
    ).setStyles({
      'position': 'absolute',
      'display': 'block',
      'opacity': 0
    });
    
    if (this.options.showCaption) {
      this.caption = new Element('div').addClass('caption').injectInside(this.box);      
    }
    
    this.box_fx = new Fx.Morph(this.box, {duration: 200}).addEvent('onComplete', this.showImage);
    this.image_box_fx = new Fx.Morph(this.image_box, {duration: 200}).addEvent('onComplete', this.showImage);
  },
  
  zoomIn: function() {
    if (this.box) this.box.removeClass('zoombox-loading');
    
    var wsize = window.getSize();
    var width = this.image.width +
      this.image.getStyle('margin-left').toInt() + this.image.getStyle('margin-right').toInt() +
      this.image.getStyle('border-left-width').toInt() + this.image.getStyle('border-right-width').toInt();
    var height = this.image.height +
      this.image.getStyle('margin-top').toInt() + this.image.getStyle('margin-bottom').toInt() +
      this.image.getStyle('border-bottom-width').toInt() + this.image.getStyle('border-bottom-width').toInt();
    
    // zoom
    var y = this.scrollTop + (wsize.y - (height + ((this.options.showCaption && this.captionText.trim() != '') ? this.options.captionMinHeight : 0))) / 2;
    if (y < this.options.topOffset) y = this.options.topOffset;
    this.box_fx.start({
      'left': (wsize.x - width) / 2,
      'top': y,
      'width': width,
      'height': height
    });
    this.image_box_fx.start({
      'width': width,
      'height': height
    });
    
    if (this.current_image > 0) {
      this.prev_img.tween('opacity', 1);
      this.prev_btn.setStyle('display', 'block');
    }
    if (this.current_image < (this.galleries[this.current_gallery].length - 1)) {
      this.next_img.tween('opacity', 1);
      this.next_btn.setStyle('display', 'block');
    }
    this.close_btn.tween('opacity', 1);
  },
  
  showImage: function() {
    if (this.options.showCaption) {
      var caption = this.image.retrieve('caption');
      if (caption) {
        this.caption.set('html', caption);
        this.caption.setStyles({
          'display': this.caption.retrieve('caption-display', 'block'),
          'visibility': 'visible',
          'opacity': 0
        }).set('tween', {duration: 150}).tween('opacity', 1);
      }
    }
    this.image_box.setStyles({
      'visibility': 'visible',
      'opacity': 0
    }).tween('opacity', 1);
  },
  
  prev: function() {
    if (this.current_image <= 0) return;
    this.current_image--;
    try {
      this.load(this.galleries[this.current_gallery][this.current_image]);
    } catch(e) {
      if (console) console.log(e);
    }
  },
  
  next: function() {
    if (this.current_image >= this.galleries[this.current_gallery].length) return;
    this.current_image++;
    try {
      this.load(this.galleries[this.current_gallery][this.current_image]);
    } catch(e) {
      if (console) console.log(e);
    }
  }
  
});

var zoombox;
window.addEvent('domready', function() {
  zoombox = new ZoomBox({overlayOpacity: 0.5});
});