var siteFeedBack = Class.create();
	siteFeedBack.prototype =
	{
		initialize: function( feedback_form_id, mandatory_inputs_class, feedback_status_container_id )
		{
			this.wait_alt = 'Sending, please wait...';
			this.msg_empty = 'Empty field: ';
			this.msg_mismatch = 'Wrong value for: ';
			this.msg_too_short = 'Value is too short in field: ';
			this.msg_sent = 'Message successfully sent.';
			this.msg_not_sent = 'Failed to send message.';

			this.mandatory_inputs_class = mandatory_inputs_class;
			this.min_length = 10;
			this.use_alert = false;
			this.max_rows = 15;
			this.min_rows = 3;

			this.text_fields = new Array();
			this.strict_fields = new Array();

			this.feedback_form = $(feedback_form_id);
			this.feedback_form.onsubmit = function(){ return false; }

			this.status = $(feedback_status_container_id);
			Element.hide(this.status);

			return true;
		},

		init: function()
		{
			this.feedback_form.getElements().each( this.filter.bind(this) );
			Event.observe
			(
				this.feedback_form,
				'submit',
				this.send.bind(this)
			);

			Event.observe
			(
				this.feedback_form,
				'keydown',
				this.checkPressedButton.bind(this)
			);
		},

		filter: function(input)
		{
			if( ['text','password','textarea'].indexOf(input.type) != -1 )
			{
				this.text_fields.push(input);

				if( input.hasClassName(this.mandatory_inputs_class) )
				{
					this.strict_fields.push(input);
				}

				Event.observe
				(
					input,
					'focus',
					this.setFocus.bind(this, input )
				);

				Event.observe
				(
					input,
					'focus',
					this.showMessage.bind(this,'')
				);

				Event.observe
				(
					input,
					'blur',
					this.setBlur.bind(this, input )
				);

				if( input.type == 'textarea' )
				{
					Event.observe
					(
						input,
						'keydown',
						this.resizeTextArea.bind(this, input )
					);
					Event.observe
					(
						input,
						'change',
						this.resizeTextArea.bind(this, input )
					);
					Event.observe
					(
						input,
						'focus',
						this.resizeTextArea.bind(this, input )
					);
					Event.observe
					(
						input,
						'blur',
						this.resizeTextArea.bind(this, input )
					);
				}

				this.setBlur(input);
			}
			return true;
		},

		resizeTextArea: function( textarea )
		{
			this.nesessary_rows = Math.round( textarea.value.strip().length / textarea.cols );
			if( this.nesessary_rows > this.max_rows ){ this.nesessary_rows = this.max_rows; }
			if( this.nesessary_rows < this.min_rows ){ this.nesessary_rows = this.min_rows; }
			if( textarea.rows != this.nesessary_rows) textarea.rows = this.nesessary_rows;
			return true;
		},

		protectEmail: function( insertion_point_id, input_class, input_title, tabindex, id_suffix )
		{
			this.input_str = '<'+'in'+'put'+' class="'+ input_class +'" tabindex="'+ tabindex +'" type="t'+'ext"'+' value="" title="'+ input_title +'" maxlength="70" name="feed'+'back_e'+'mail" id="feed'+'back_em'+'ail'+id_suffix+'"'+'>';
			Element.update(insertion_point_id,this.input_str);
		},

		checkPressedButton: function(event)
		{
			if( event.ctrlKey && event.keyCode == Event.KEY_RETURN )
			{
				this.send();
			}
		},

		setFocus: function( input )
		{
			input.value = ( input.value.strip() == input.title ) ? '' : input.value.strip();
			return true;
		},

		setBlur: function( input)
		{
			input.value = ( input.value.strip() == '' ) ? input.title : input.value.strip();
			return true;
		},

		checkMail: function( input )
		{
			return  /^\w+[A-Za-z0-9\-\_\.]{1,50}\w+@\w+\.?[a-z0-9\-\_]{1,30}\.[a-z]{2,4}$/.test( input.value ) ;
		},

		validate: function( input )
		{
			input.value = input.value.strip();
			if( (input.value == input.title) || (input.value == '') )
			{
				this.showMessage( this.msg_empty + input.title  );
				return false;
			}

			if( input.name.indexOf('mail') != -1 )
			{
				if( !this.checkMail(input) )
				{
					this.showMessage( this.msg_mismatch + input.title );
					return false;
				}
			}

			if( input.name.indexOf('message') != -1 && input.value.length < this.min_length )
			{
				this.showMessage( this.msg_too_short + input.title );
				return false;
			}
			return true;
		},

		showMessage: function( message )
		{
			if( message == '' || message == undefined  )
			{
				if(this.use_alert){ return false; }
				if( this.status.innerHTML.length > 0 )
				{
					this.status.innerHTML = '';
					Element.hide(this.status);
				}
			}
			else
			{
				if(this.use_alert)
				{
					alert(message);
					return true;
				}
				this.status.innerHTML = message;
				Element.show(this.status);
			}
			return true;
		},

		send: function()
		{
			for( var i=0; i<this.strict_fields.length; i++  )
			{
				if( !this.validate( this.strict_fields[i] ) )
				{
					return false
				}
			}

			this.wait = '<img src="images/other/wait.gif" alt="Sending..." title="'+ this.wait_alt +'">';
			this.showMessage(this.wait);
			this.parameters = Form.serialize(this.feedback_form);
			this.feedback_form.disable();

			this.feedback_request = new Ajax.Request( this.feedback_form.action,
						{
							method: "post",
							parameters: this.parameters+'&ajax',
							onComplete: this.reply.bind(this)
						} );
			return true;
		},

		reply: function( request )
		{
			this.feedback_form.enable();
			if( request.responseText == 'NOT_SENT' )
			{
				this.showMessage(this.msg_not_sent);
			}
			else
			{
				this.showMessage(this.msg_sent);
				this.reset();
			}

			return true;
		},

		reset: function()
		{
			this.text_fields.each(
				function(field)
				{
					field.value = field.title;
				}
			);
		}
	};