/**
*>*************************************************************************<
* Name : uploadConstruct
* Author : Ed Cradock
* Date : 4 May 2006
* 
* Method  : __construct
*
* @param object simplejax - Simplejax object for callback script

* @return none
*
* Description:
* Upload construct object to handle an uploaded file
*>**************************************************************************<
*/
var _this;
function uploadConstruct(simplejax, statusurl)
{  
   //Setup vital properties
   this.curWidth = 0;                  // Current width of loadbar
   this.destWidth = 0;                 // Destination width of loadbar
   this.speed = 5;                     // Loadbar speed
   this.startTime = 0;                 // Upload started
   this.checkUpdate = 4;               // Refresh rate
   
   //Setup timers
   this.timer = '';
   this.loadbarTimer = '';

   // Error thresholds
   this.curFail = 0;                   // Current failures
   this.failMax = 5;                   // Maximum failures
   this.fail = false;                  // Generic failure
   this.errorPass = 2;                 // Concurrent errors before verified
   this.maxPasses = 2;                 // Maximum passes
   this.errorPasses = 1;               // Current error passes
   
   // Processed signal messages
   this.signals = new Array
   (
      /*0*/ 'The server could not process your request.', null,
      /*2*/ 'Your session has expired or cookies are not enabled, please refresh.',
      /*3*/ 'Filesize is invalid, please check the front page for the acceptable filesize.',
      /*4*/ 'Invalid filetype. Please only upload .rar files.',
      /*5*/ 'Filename contains illegal characters, please ensure no foreign characters or white space are present (spaces etc).',
      /*6*/ 'The captcha text entered does not match the image. <a href="javascript:void(0);" onclick="upload.captcha(\'' + this.instance + '\');"><strong>Try again</strong></a>'
   );

   //Assign the simplejax object
   simplejax.set('URL', statusurl);
   simplejax.set('CALLBACK', this.status);
   this.simplejax = simplejax;
   
   // Extract the instance (6 characters)
   var len = statusurl.length;
   this.instance = statusurl.substr((len -6), len-1);
   
   _this = this;
}

/**
*>***************************************************************<
* Method : status
* Access : PUBLIC 
*
* @param string dataRecv - Data received from simplejax connection
*
* @return boolean
*
* Description:
* The main processing for the upload bar
*>***************************************************************<
*/
uploadConstruct.prototype.status = function(dataRecv)
{
   if(!dataRecv) 
      _this.fail = true;

   var loadbar = eval(dataRecv);
   var error = loadbar.error;
   var signal = loadbar.signal;
   var skip = (typeof(loadbar.skip) != 'undefined') ? true : false;
   var context = loadbar.context;
   var failed = false;

   //Check for error
   if(_this.fail === true 
      || (error == true && _this.errorPasses == _this.maxPasses) 
      || (_this.curFail >= _this.failMax)
      || (skip == true))
   {
      //Reset error passes
      _this.errorPasses = 1;

      /*
         Translate error signals
      */
      var errStr;
      switch(signal)
      {
         case 0: errStr = _this.signals[0]; break;
         case 2: errStr = _this.signals[2]; break;
         case 3: errStr = _this.signals[3]; break;
         case 4: errStr = _this.signals[4]; break;
         case 5: errStr = _this.signals[5]; break;
         case 6: errStr = _this.signals[6]; break;

         default: errStr = 'Unknown error.';
      }
         
      _this.getElem('hiddenFrame').src = '';
      _this.getElem('uploadbox3').style.display = 'none';

      //Set contextual error & change step
      _this.getElem('contextualError').innerHTML = errStr;
      _this.changeStep(6);

      _this.destruct();
      
      return false;
   }else if(error === true && (_this.errorPasses < _this.maxPasses)){
      _this.errorPasses++;
      return false;
   }

   var totalBytes = loadbar.bytesTotal;            // File size in bytes
   var loadedBytes = loadbar.bytesLoaded;         // Bytes loaded
   var percentage = (loadedBytes / totalBytes) * 100;
   percentage = Math.round(percentage);            // Percentage complete

   /*
      Evil hack for ridiculously small rar files
   */
   if(percentage == '98')
      percentage = '100';

   var failed = false;
   if(isNaN(percentage) || typeof(percentage) == 'undefined')
      failed = true;

   //Calculate speed
   var dateObj = new Date();
   var Curtime = dateObj.getTime() / 1000;
   Curtime = Math.round(Curtime);

   var elapsed = Curtime - _this.startTime;
   if(elapsed != 0)
   {
      var Speed = loadedBytes / elapsed;
      var KilaBytes = _this.speedInKB(Speed);
      var remaining = (totalBytes - loadedBytes) / Speed;

      _this.getElem('stats').innerHTML = remaining + " - ";
      remaining = Math.round(remaining);
      
      var finalOutput = _this.remaining(remaining);

      if(failed == false)
      {
         _this.getElem('stats').innerHTML = finalOutput + ' remaining | ' + KilaBytes + ' kb/s upload speed';
         _this.getElem('tab2').innerHTML = percentage + '% .rar completed';
      }else{
         _this.curFail++;
         _this.getElem('stats').innerHTML = 'Loading...';
      }
   }

   _this.destWidth = percentage;
}

/**
*>***************************************************************<
* Method : speed
* Access : private 
*
* @param int speed - current speed
*
* @return int
*
* Description:
* Calculates speed in kb
*>***************************************************************<
*/ 
uploadConstruct.prototype.speedInKB = function(speed)
{
   var bits = speed * 8;
   var bytes = bits / 1024;
   var kilabytes = bytes / 8;
   
   return Math.round(kilabytes);
}

/**
*>***************************************************************<
* Method : remaining
* Access : PUBLIC 
*
* @param int remaining - Calculated time remaining
*
* @return string
*
* Description:
* Creates a human readable time remaining from a second 
* representation
*>***************************************************************<
*/ 
uploadConstruct.prototype.remaining = function(remaining)
{
   var units = new Array(1, 60, 3600);
   units = units.reverse();
   var unitNames = new Array('sec', 'min', 'hr');
   unitNames = unitNames.reverse();

   var output = new Array();
   for(unit in units)
   {
      if(remaining >= units[unit])
      {
         var quotient = Math.floor(remaining / units[unit]);
         remaining = remaining % units[unit];
         output.push(quotient + ' ' + ((quotient == 1) ? unitNames[unit] : unitNames[unit] + 's'));
      }
   }

   if(output.length > 2)
      output.pop();

   if(output.length > 1)
   {
      var last = output.pop();
      var finalstr = output.join(', ') + ' and ' + last;
   }else
      var finalstr = output.pop();

   return finalstr;
}

/**
*>***************************************************************<
* Method : update
* Access : PUBLIC 
*
* @param void
*
* @return void
*
* Description:
* Set on a timer will update the upload bar every 100ms
*>***************************************************************<
*/ 
uploadConstruct.prototype.update = function()
{
   //Date object
   var dateObj = new Date();

   //Set start time
   this.startTime = dateObj.getTime() / 1000;
   this.startTime = Math.round(this.startTime);

   //Invoke first off
   this.simplejax.invoke()
   
   //Set on interval
   this.timer = setInterval(function(){ _this.simplejax.invoke() }, (this.checkUpdate * 1000));
   
   var _this = this;
   //Start loadbarTimer
   this.loadbarTimer = setInterval(
      function()
      {
         _this.curWidth = parseInt(_this.getElem('loadbar').style.width);

         if(_this.curWidth == 100 || _this.destWidth == 100)
         {
            setTimeout(function(){ _this.changeStep(4) }, 2000);
            _this.getElem('stats').innerHTML = 'Completed';
            _this.getElem('loadbar').style.width = '100%';

            _this.destruct();
         }else if(_this.curWidth < _this.destWidth)
         {
            _this.curWidth += 1;
            _this.getElem('loadbar').style.width = _this.curWidth + '%';
         }
      }
   , 100);
}

/**
*>***************************************************************<
* Method : getElem
* Access : PUBLIC 
*
* @param ElementID - Id for the element to return
*
* @return void
*
* Description:
* Wrapper for returning the gebid for the instructed element
*>***************************************************************<
*/  
uploadConstruct.prototype.getElem = function(ElementID)
{
   var element = document.getElementById(ElementID);
   var exists = eval(element);

   if(exists)
      return element;
   else
   {
      alert('Provided element \'' + ElementID + '\' does not exist');
      return false;
   }
}

/**
*>***************************************************************<
* Method : changeStep
* Access : PUBLIC 
*
* @param int num - The step to switch to
*
* @return void
*
* Description:
* Hides/shows a layer in numerical order
*>***************************************************************<
*/  
uploadConstruct.prototype.changeStep = function(num)
{
   var layerFamily = 'uploadbox';
   var previousSibling = this.getElem(layerFamily + (num - 1));
   var element = this.getElem(layerFamily + num);

   if(element && previousSibling)
   {
      // Hide current step
      previousSibling.style.display = 'none';
      previousSibling.style.visibility = 'hidden';
      
      // Display next step
      element.style.display = 'block';
      element.style.visibility = 'visible';
   }
}

/**
*>***************************************************************<
* Method : startDialog
* Access : PUBLIC 
*
* @param void
*
* @return void
*
* Description:
* Display step one and fade out background uploadbox
*>***************************************************************<
*/   
uploadConstruct.prototype.startDialog = function()
{
   if(this.getElem('a').value == '')
      return false;

   var element = this.getElem('uploadbox1')
   element.style.display = 'block';

   //Fade out all other elements
   var divs = this.getElem('CenterContainer').getElementsByTagName('div');
   var opacValue = 10;
   var opacStop = 5;

   changeOpac = setInterval(
      function(){
      for(var i = 0; i <= divs.length-1; i++)
      {
         if(divs[i].id.substr(0, 9) != 'uploadbox') 
         {
               _this.getElem('logo').style.opacity = opacValue / 10;
               _this.getElem('logo').style.filter = 'alpha(opacity=' + (opacValue * 10) + ')';
               divs[i].style.opacity = opacValue / 10;
               divs[i].style.filter = 'alpha(opacity=' + (opacValue * 10) + ')';
         }else
            continue;
      }

      if(opacValue != opacStop)
         opacValue--;
      else
         clearInterval(changeOpac);
   }, 100);
   
   this.getElem('uploadit').disabled = true;
}

/**
*>***************************************************************<
* Method : terms
* Access : PUBLIC 
*
* @param object element - the element to check
*
* @return void
*
* Description:
* Validates that the user has agreed to tos
*>***************************************************************<
*/
uploadConstruct.prototype.terms = function(element)
{
   if(element.checked == false)
      alert('You must agree to the terms of service before uploading.');
   else
   {
      this.changeStep(2);
      this.upload();
   }
}

/**
*>***************************************************************<
* Method : upload
* Access : PUBLIC 
*
* @param void
*
* @return void
*
* Description:
* Triggers the upload to begin (controlled by the user)
*>***************************************************************<
*/     
uploadConstruct.prototype.upload = function()
{
   if(this.getElem('checktwo').checked != true)
   {
      alert('You must agree to the terms of service before uploading.');
      return false;
   }else
      this.getElem('agreed').value = '1';

   //Set captcha id
   this.getElem('boxform').action += this.getElem('captcha').value;

   //Set up previously set values for hidden fields
   if(this.getElem('filedescription').value.length > 0)
      this.getElem('description').value = this.getElem('filedescription').value;

   if(this.getElem('checkone').checked == true)
      this.getElem('display').value = '1';
   else
      this.getElem('display').value = '0';

   document.forms['uploadForm'].submit();
   this.changeStep(3);
   this.update();
}

/**
*>***************************************************************<
* Method : showid
* Access : PUBLIC 
*
* @param void
*
* @return void
*
* Description:
* Displays unique file id
*>***************************************************************<
*/    
uploadConstruct.prototype.showid = function()
{
   prompt('Your unique id is located below:', this.instance);
}

/**
*>***************************************************************<
* Method : captcha
* Access : PUBLIC 
*
* @param void
*
* @return void
*
* Description:
* Updates captcha id and reloads image
*>***************************************************************<
*/    
uploadConstruct.prototype.captcha = function()
{
   //Refresh session
   var time = new Date();
   this.getElem('hiddenFrame').src = 'captcha/set.php?instance=' + this.instance;

   //Give it some time to load the page
   setTimeout(
   function() 
   {
      _this.getElem('uploadbox6').style.display = 'none';
      _this.getElem('uploadbox2').style.display = 'block';
      _this.getElem('uploadbox2').style.visibility = 'visible';
      _this.getElem('captcha').value = '';
      _this.getElem('captchaImg').src = '/captcha/image.php?instance=' + _this.instance + '&' + time.getTime();
   }, 500);
}

/**
*>***************************************************************<
* Method : destruct
* Access : private
*
* @param void
*
* @return void
*
* Description:
* Destroys set intervals
*>***************************************************************<
*/
uploadConstruct.prototype.destruct = function()
{
   clearInterval(this.timer);
   clearInterval(this.loadbarTimer);
}