/**
 * Convert a single file-input element into a 'multiple' input list
 *
 * Usage:
 *
 *   1. Create a file input element (no name)
 *      eg. <input type="file" id="first_file_element">
 *
 *   2. Create a DIV for the output to be written to
 *      eg. <div id="files_list"></div>
 *
 *   3. Instantiate a MultiSelector object, passing in the DIV and an (optional) maximum number of files
 *      eg. var multi_selector = new MultiSelector( document.getElementById( 'files_list' ), 3 );
 *
 *   4. Add the first element
 *      eg. multi_selector.addElement( document.getElementById( 'first_file_element' ) );
 *
 *   5. That's it.
 *
 *   You might (will) want to play around with the addListRow() method to make the output prettier.
 *
 *   You might also want to change the line 
 *       element.name = 'file_' + this.count;
 *   ...to a naming convention that makes more sense to you.
 * 
 * Licence:
 *   Use this however/wherever you like, just don't blame me if it breaks anything.
 *
 * Credit:
 *   If you're nice, you'll leave this bit:
 *  
 *   Class by Stickman -- http://www.the-stickman.com
 *      with thanks to:
 *      [for Safari fixes]
 *         Luis Torrefranca -- http://www.law.pitt.edu
 *         and
 *         Shawn Parker & John Pennypacker -- http://www.fuzzycoconut.com
 *      [for duplicate name bug]
 *         'neal'
 */
function MultiSelector( list_target, max ){

	// Where to write the list
	this.list_target = list_target;
	// How many elements?
	this.count = 0;
	// How many elements?
	this.id = 0;
	// Is there a maximum?
	if( max ){
		this.max = max;
	} else {
		this.max = -1;
	};
	
	/**
	 * Add a new file input element
	 */
	this.addElement = function( element ){
        // Make sure element is not NULL
        if ( element )
        {           
		    // Make sure it's a file input element
		    if( element.tagName == 'INPUT' && element.type == 'file' ){
			    // Element name -- what number am I?
			    element.name = 'file_' + this.id++;

			    // Add reference to this object
			    element.multi_selector = this;

			    // What to do when a file is selected
			    element.onchange = function(){

				    // New file input
				    var new_element = document.createElement( 'input' );
				    new_element.type = 'file';

				    // Add new element
				    this.parentNode.insertBefore( new_element, this );

				    // Apply 'update' to element
				    this.multi_selector.addElement( new_element );

				    // Update list
				    this.multi_selector.addListRow( this );

				    // Hide this: we can't use display:none because Safari doesn't like it
				    this.style.position = 'absolute';
				    this.style.left = '-1000px';

			    };
			    // If we've reached maximum number, disable input element
			    if( this.max != -1 && this.count >= this.max ){
				    element.disabled = true;
			    };

			    // File element counter
			    this.count++;
			    // Most recent element
			    this.current_element = element;
    			
		    } else {
			    // This can only be applied to file input elements!
			    alert( 'Error: not a file input element' );
		    };        
        }


	};

	/**
	 * Add a new row to the list of files
	 */
	this.addListRow = function( element ){
        // Clear the upload report
        if (document.getElementById('ctl00_content_PropertyDetails1_ImageGallery1_ImageUploader1_lblUploadReport'))
        {
            document.getElementById('ctl00_content_PropertyDetails1_ImageGallery1_ImageUploader1_lblUploadReport').innerHTML = '';
        }
               
		// Row div
		var new_row = document.createElement( 'div' );
        new_row.className = 'imageuploaderlistitem';
        
        // Delete DIV
        //var new_row_button_container = document.createElement( 'div' );
        //new_row_button_container.className = 'imageuploadlistbutton';
        
		// Delete button
		var new_row_button = document.createElement( 'input' );
		new_row_button.type = 'button';
		new_row_button.value = 'Remove';

		// References
		new_row.element = element;

		// Delete function
		new_row_button.onclick= function(){

			// Remove element from form
			this.parentNode.element.parentNode.removeChild( this.parentNode.element );

			// Remove this row from the list
			this.parentNode.parentNode.removeChild( this.parentNode );

			// Decrement counter
			this.parentNode.element.multi_selector.count--;

			// Re-enable input element (if it's disabled)
			this.parentNode.element.multi_selector.current_element.disabled = false;

			// Appease Safari
			//    without it Safari wants to reload the browser window
			//    which nixes your already queued uploads
			return false;
		};

		// Set row value
		//new_row.innerHTML = element.value;
        new_row.innerHTML = this.ParseFilename(element.value);
		// Add button container
		//new_row_button_container.appendChild( new_row_button );
		// Add button
		new_row.appendChild( new_row_button );

		// Add it to the list
		this.list_target.appendChild( new_row );
		
	};

    this.ParseFilename = function( filename )
    {
        if ( filename )
        {
            var lastPathDelimiter = filename.lastIndexOf("\\");
            return filename.substring(lastPathDelimiter+1);
        }
    };
};