/**
 * @author Ryan Johnson <ryan@livepipe.net>
 * @copyright 2007 LivePipe LLC
 * @package Control.TextArea
 * @license MIT
 * @url http://livepipe.net/projects/control_textarea/
 * @version 2.0.1
 */

if(typeof(Control) == 'undefined')
	Control = {};
Control.TextArea = Class.create();
Object.extend(Control.TextArea.prototype,{
	onChangeTimeoutLength: 500,
	element: false,
	onChangeTimeout: false,
	initialize: function(textarea){
		this.element = $(textarea);
		$(this.element).observe('keyup',this.doOnChange.bindAsEventListener(this));
		$(this.element).observe('paste',this.doOnChange.bindAsEventListener(this));
		$(this.element).observe('input',this.doOnChange.bindAsEventListener(this));
		if(!!document.selection){
			$(this.element).observe('mouseup',this.saveRange.bindAsEventListener(this));  
			$(this.element).observe('keyup',this.saveRange.bindAsEventListener(this));
		}
	},
	doOnChange: function(event){
		if(this.onChangeTimeout)
			window.clearTimeout(this.onChangeTimeout);
		this.onChangeTimeout = window.setTimeout(function(){
			if(this.notify)
				this.notify('change',this.getValue());
		}.bind(this),this.onChangeTimeoutLength);
	},
	saveRange: function(){
		this.range = document.selection.createRange();  
	},
	getValue: function(){
		return this.element.value;
	},
	setValue: function(val) {
		this.element.value = val;
	},
	getSelection: function(){
		if(!!document.selection)
			return document.selection.createRange().text;
		else if(!!this.element.setSelectionRange)
			return this.element.value.substring(this.element.selectionStart,this.element.selectionEnd);
		else
			return false;
	},
	setSelection: function(start, end) {
		if(!!document.selection){
			var range = this.element.createTextRange();
			range.collapse(true);
			range.moveEnd('character', end);
			range.moveStart('character', start);
			range.select();
		}
		else
			this.element.setSelectionRange(start, end);
	},
	replaceSelection: function(text){
		var scroll_top = this.element.scrollTop;
		if(!!document.selection){
			this.element.focus();
			var range = (this.range) ? this.range : document.selection.createRange();
			range.text = text;
			range.select();
		}else if(!!this.element.setSelectionRange){
			var selection_start = this.element.selectionStart;
			this.element.value = this.element.value.substring(0,selection_start) + text + this.element.value.substring(this.element.selectionEnd);
			this.element.setSelectionRange(selection_start + text.length,selection_start + text.length);
		}
		this.doOnChange();
		this.element.focus();
		this.element.scrollTop = scroll_top;
	},
	wrapSelection: function(before,after){
		this.replaceSelection(before + this.getSelection() + after);
	},
	insertBeforeSelection: function(text){
		this.replaceSelection(text + this.getSelection());
	},
	insertAfterSelection: function(text){
		this.replaceSelection(this.getSelection() + text);
	},
	injectEachSelectedLine: function(callback,before,after){
		this.replaceSelection((before || '') + $A(this.getSelection().split("\n")).inject([],callback).join("\n") + (after || ''));
	},
	insertBeforeEachSelectedLine: function(text,before,after){
		this.injectEachSelectedLine(function(lines,line){
			lines.push(text + line);
			return lines;
		},before,after);
	}
});
if(typeof(Object.Event) != 'undefined')
	Object.Event.extend(Control.TextArea);