/**
* Ajax upload
* Project page - http://valums.com/ajax-upload/
* Copyright (c) 2008 Andris Valums, http://valums.com
* Licensed under the MIT license (http://valums.com/mit-license/)
* Version 3.1 (24.04.2009)
*/

/**
* Changes from the previous version:
* 1. Fixed Safari 4 (Mac) upload problem
* Special thanks to Lauren Russell, Mike, Steffen for finding what caused this bug
* 2. Improved compatability with jquery ui.
* Thanks to Vladimir Shushkov
* 3. Fixed problems with Opera, but you can't use false as a response now.
* 
* For the full changelog please visit: 
* http://valums.com/ajax-upload-changelog/
*/

(function()
{

  var d = document, w = window;

  /**
  * Get element by id
  */
  function get(element)
  {
    if (typeof element == "string")
      element = d.getElementById(element);
    return element;
  }

  /**
  * Attaches event to a dom element
  */
  function addEvent(el, type, fn)
  {
    if (w.addEventListener)
    {
      el.addEventListener(type, fn, false);
    } else if (w.attachEvent)
    {
      var f = function()
      {
        fn.call(el, w.event);
      };
      el.attachEvent('on' + type, f)
    }
  }


  /**
  * Creates and returns element from html chunk
  */
  var toElement = function()
  {
    var div = d.createElement('div');
    return function(html)
    {
      div.innerHTML = html;
      var el = div.childNodes[0];
      div.removeChild(el);
      return el;
    }
  } ();

  function hasClass(ele, cls)
  {
    return ele.className.match(new RegExp('(\\s|^)' + cls + '(\\s|$)'));
  }
  function addClass(ele, cls)
  {
    if (!hasClass(ele, cls)) ele.className += " " + cls;
  }
  function removeClass(ele, cls)
  {
    var reg = new RegExp('(\\s|^)' + cls + '(\\s|$)');
    ele.className = ele.className.replace(reg, ' ');
  }

  // getOffset function copied from jQuery lib (http://jquery.com/)
  if (document.documentElement["getBoundingClientRect"])
  {
    // Get Offset using getBoundingClientRect
    // http://ejohn.org/blog/getboundingclientrect-is-awesome/
    var getOffset = function(el)
    {
      var box = el.getBoundingClientRect(),
		doc = el.ownerDocument,
		body = doc.body,
		docElem = doc.documentElement,

      // for ie 
		clientTop = docElem.clientTop || body.clientTop || 0,
		clientLeft = docElem.clientLeft || body.clientLeft || 0,

      // In Internet Explorer 7 getBoundingClientRect property is treated as physical,
      // while others are logical. Make all logical, like in IE8.


		zoom = 1;
      if (body.getBoundingClientRect)
      {
        var bound = body.getBoundingClientRect();
        zoom = (bound.right - bound.left) / body.clientWidth;
      }
      if (zoom > 1)
      {
        clientTop = 0;
        clientLeft = 0;
      }
      var top = box.top / zoom + (window.pageYOffset || docElem && docElem.scrollTop / zoom || body.scrollTop / zoom) - clientTop,
		left = box.left / zoom + (window.pageXOffset || docElem && docElem.scrollLeft / zoom || body.scrollLeft / zoom) - clientLeft;

      return {
        top: top,
        left: left
      };
    }

  } else
  {
    // Get offset adding all offsets 
    var getOffset = function(el)
    {
      if (w.jQuery)
      {
        return jQuery(el).offset();
      }

      var top = 0, left = 0;
      do
      {
        top += el.offsetTop || 0;
        left += el.offsetLeft || 0;
      }
      while (el = el.offsetParent);

      return {
        left: left,
        top: top
      };
    }
  }

  function getBox(el)
  {
    var left, right, top, bottom;
    var offset = getOffset(el);
    left = offset.left;
    top = offset.top;

    right = left + el.offsetWidth;
    bottom = top + el.offsetHeight;

    return {
      left: left,
      right: right,
      top: top,
      bottom: bottom
    };
  }

  /**
  * Crossbrowser mouse coordinates
  */
  function getMouseCoords(e)
  {
    // pageX/Y is not supported in IE
    // http://www.quirksmode.org/dom/w3c_cssom.html			
    if (!e.pageX && e.clientX)
    {
      // In Internet Explorer 7 some properties (mouse coordinates) are treated as physical,
      // while others are logical (offset).
      var zoom = 1;
      var body = document.body;

      if (body.getBoundingClientRect)
      {
        var bound = body.getBoundingClientRect();
        zoom = (bound.right - bound.left) / body.clientWidth;
      }

      return {
        x: e.clientX / zoom + d.body.scrollLeft + d.documentElement.scrollLeft,
        y: e.clientY / zoom + d.body.scrollTop + d.documentElement.scrollTop
      };
    }

    return {
      x: e.pageX,
      y: e.pageY
    };

  }
  /**
  * Function generates unique id
  */
  var getUID = function()
  {
    var id = 0;
    return function()
    {
      return 'ValumsAjaxUpload' + id++;
    }
  } ();

  function fileFromPath(file)
  {
    return file.replace(/.*(\/|\\)/, "");
  }

  function getExt(file)
  {
    return (/[.]/.exec(file)) ? /[^.]+$/.exec(file.toLowerCase()) : '';
  }

  // Please use AjaxUpload , Ajax_upload will be removed in the next version
  Ajax_upload = AjaxUpload = function(button, options)
  {
    if (button.jquery)
    {
      // jquery object was passed
      button = button[0];
    } else if (typeof button == "string" && /^#.*/.test(button))
    {
      button = button.slice(1);
    }
    button = get(button);

    this._input = null;
    this._button = button;
    this._disabled = false;
    this._submitting = false;
    // Variable changes to true if the button was clicked
    // 3 seconds ago (requred to fix Safari on Mac error)
    this._justClicked = false;
    this._parentDialog = d.body;

    if (window.jQuery && jQuery.ui && jQuery.ui.dialog)
    {
      var parentDialog = jQuery(self._button).parents('.ui-dialog-content');
      if (parentDialog.length)
      {
        this._parentDialog = parentDialog[0];
      }
    }

    this._settings = {
      // Location of the server-side upload script
      action: 'upload.php',
      // File upload name
      name: 'userfile',
      // Additional data to send
      data: {},
      // Submit file as soon as it's selected
      autoSubmit: true,
      // The type of data that you're expecting back from the server.
      // Html and xml are detected automatically.
      // Only useful when you are using json data as a response.
      // Set to "json" in that case. 
      responseType: false,
      // When user selects a file, useful with autoSubmit disabled			
      onChange: function(file, extension) { },
      // Callback to fire before file is uploaded
      // You can return false to cancel upload
      onSubmit: function(file, extension) { },
      // Fired when file upload is completed
      onComplete: function(file, response) { }
    };

    // Merge the users options with our defaults
    for (var i in options)
    {
      this._settings[i] = options[i];
    }

    this._createInput();
    this._rerouteClicks();
  }

  // assigning methods to our class
  AjaxUpload.prototype = {
    setData: function(data)
    {
      this._settings.data = data;
    },
    disable: function()
    {
      this._disabled = true;
    },
    enable: function()
    {
      this._disabled = false;
    },
    // removes ajaxupload
    destroy: function()
    {
      if (this._input)
      {
        if (this._input.parentNode)
        {
          this._input.parentNode.removeChild(this._input);
        }
        this._input = null;
      }
    },
    /**
    * Creates invisible file input above the button 
    */
    _createInput: function()
    {
      var self = this;
      var input = d.createElement("input");
      input.setAttribute('type', 'file');
      input.setAttribute('name', this._settings.name);
      var styles = {
        'position': 'absolute'
			, 'margin': '-5px 0 0 -175px'
			, 'padding': 0
			, 'width': '220px'
			, 'height': '30px'
			, 'opacity': 0
			, 'cursor': 'pointer'
			, 'display': 'none'
			, 'zIndex': 2147483583 //Max zIndex supported by Opera 9.0-9.2x 
        // Strange, I expected 2147483647					
      };
      for (var i in styles)
      {
        input.style[i] = styles[i];
      }

      // Make sure that element opacity exists
      // (IE uses filter instead)
      if (!(input.style.opacity === "0"))
      {
        input.style.filter = "alpha(opacity=0)";
      }

      this._parentDialog.appendChild(input);

      addEvent(input, 'change', function()
      {
        // get filename from input
        var file = fileFromPath(this.value);
        if (self._settings.onChange.call(self, file, getExt(file)) == false)
        {
          return;
        }
        // Submit form when value is changed
        if (self._settings.autoSubmit)
        {
          self.submit();
        }
      });

      // Fixing problem with Safari
      // The problem is that if you leave input before the file select dialog opens
      // it does not upload the file.
      // As dialog opens slowly (it is a sheet dialog which takes some time to open)
      // there is some time while you can leave the button.
      // So we should not change display to none immediately
      addEvent(input, 'click', function()
      {
        self.justClicked = true;
        setTimeout(function()
        {
          // we will wait 3 seconds for dialog to open
          self.justClicked = false;
        }, 3000);
      });

      this._input = input;
    },
    _rerouteClicks: function()
    {
      var self = this;

      // IE displays 'access denied' error when using this method
      // other browsers just ignore click()
      // addEvent(this._button, 'click', function(e){
      //   self._input.click();
      // });

      var box, dialogOffset = { top: 0, left: 0 }, over = false;
      addEvent(self._button, 'mouseover', function(e)
      {
        if (!self._input || over) return;
        over = true;
        box = getBox(self._button);

        if (self._parentDialog != d.body)
        {
          dialogOffset = getOffset(self._parentDialog);
        }
      });


      // we can't use mouseout on the button,
      // because invisible input is over it
      addEvent(document, 'mousemove', function(e)
      {
        var input = self._input;
        if (!input || !over) return;

        if (self._disabled)
        {
          removeClass(self._button, 'hover');
          input.style.display = 'none';
          return;
        }

        var c = getMouseCoords(e);

        if ((c.x >= box.left) && (c.x <= box.right) &&
			(c.y >= box.top) && (c.y <= box.bottom))
        {
          input.style.top = c.y - dialogOffset.top + 'px';
          input.style.left = c.x - dialogOffset.left + 'px';
          input.style.display = 'block';
          addClass(self._button, 'hover');
        } else
        {
          // mouse left the button
          over = false;
          if (!self.justClicked)
          {
            input.style.display = 'none';
          }
          removeClass(self._button, 'hover');
        }
      });

    },
    /**
    * Creates iframe with unique name
    */
    _createIframe: function()
    {
      // unique name
      // We cannot use getTime, because it sometimes return
      // same value in safari :(
      var id = getUID();

      // Remove ie6 "This page contains both secure and nonsecure items" prompt 
      // http://tinyurl.com/77w9wh
      var iframe = toElement('<iframe src="javascript:false;" name="' + id + '" />');
      iframe.id = id;
      iframe.style.display = 'none';
      d.body.appendChild(iframe);
      return iframe;
    },
    /**
    * Upload file without refreshing the page
    */
    submit: function()
    {
      var self = this, settings = this._settings;

      if (this._input.value === '')
      {
        // there is no file
        return;
      }

      // get filename from input
      var file = fileFromPath(this._input.value);

      // execute user event
      if (!(settings.onSubmit.call(this, file, getExt(file)) == false))
      {
        // Create new iframe for this submission
        var iframe = this._createIframe();

        // Do not submit if user function returns false										
        var form = this._createForm(iframe);
        form.appendChild(this._input);

        form.submit();

        d.body.removeChild(form);
        form = null;
        this._input = null;

        // create new input
        this._createInput();

        var toDeleteFlag = false;

        addEvent(iframe, 'load', function(e)
        {
          if (iframe.src == "about:blank")
          {
            // First time around, do not delete.
            if (toDeleteFlag)
            {
              // Fix busy state in FF3
              setTimeout(function()
              {
                d.body.removeChild(iframe);
              }, 0);
            }
            return;
          }

          var doc = iframe.contentDocument ? iframe.contentDocument : frames[iframe.id].document;

          // fixing Opera 9.26
          if (doc.readyState && doc.readyState != 'complete')
          {
            // Opera fires load event multiple times
            // Even when the DOM is not ready yet
            // this fix should not affect other browsers
            return;
          }

          // fixing Opera 9.64
          if (doc.body && doc.body.innerHTML == "false")
          {
            // In Opera 9.64 event was fired second time
            // when body.innerHTML changed from false 
            // to server response approx. after 1 sec
            return;
          }

          var response;

          if (doc.XMLDocument)
          {
            // response is a xml document IE property
            response = doc.XMLDocument;
          } else if (doc.body)
          {
            // response is html document or plain text
            response = doc.body.innerHTML;
            if (settings.responseType == 'json')
            {
              response = window["eval"]("(" + response + ")");
            }
          } else
          {
            // response is a xml document
            var response = doc;
          }

          settings.onComplete.call(self, file, response);

          // Reload blank page, so that reloading main page
          // does not re-submit the post. Also, remember to
          // delete the frame
          toDeleteFlag = true;
          iframe.src = "about:blank"; //load event fired				 								
        });

      } else
      {
        // clear input to allow user to select same file
        this._input.value = '';
      }
    },
    /**
    * Creates form, that will be submitted to iframe
    */
    _createForm: function(iframe)
    {
      var settings = this._settings;

      // method, enctype must be specified here
      // because changing this attr on the fly is not allowed in IE 6/7		
      var form = toElement('<form method="post" enctype="multipart/form-data"></form>');
      form.style.display = 'none';
      form.action = settings.action;
      form.target = iframe.name;
      d.body.appendChild(form);

      // Create hidden input element for each data key
      for (var prop in settings.data)
      {
        var el = d.createElement("input");
        el.type = 'hidden';
        el.name = prop;
        el.value = settings.data[prop];
        form.appendChild(el);
      }
      return form;
    }
  };
})();