/*
---

script: Element.Forms.js

name: Element.Forms

description: Extends the Element native object to include methods useful in managing inputs.

license: MIT-style license

authors:
  - Aaron Newton

requires:
  - Core/Element
  - /String.Extras
  - /MooTools.More

provides: [Element.Forms]

...
*/

Element.implement({

	tidy: function(){
		this.set('value', this.get('value').tidy());
	},

	getTextInRange: function(start, end){
		return this.get('value').substring(start, end);
	},

	getSelectedText: function(){
		if (this.setSelectionRange) return this.getTextInRange(this.getSelectionStart(), this.getSelectionEnd());
		return document.selection.createRange().text;
	},

	getSelectedRange: function(){
		if (this.selectionStart != null){
			return {
				start: this.selectionStart,
				end: this.selectionEnd
			};
		}

		var pos = {
			start: 0,
			end: 0
		};
		var range = this.getDocument().selection.createRange();
		if (!range || range.parentElement() != this) return pos;
		var duplicate = range.duplicate();

		if (this.type == 'text'){
			pos.start = 0 - duplicate.moveStart('character', -100000);
			pos.end = pos.start + range.text.length;
		} else {
			var value = this.get('value');
			var offset = value.length;
			duplicate.moveToElementText(this);
			duplicate.setEndPoint('StartToEnd', range);
			if (duplicate.text.length) offset -= value.match(/[\n\r]*$/)[0].length;
			pos.end = offset - duplicate.text.length;
			duplicate.setEndPoint('StartToStart', range);
			pos.start = offset - duplicate.text.length;
		}
		return pos;
	},

	getSelectionStart: function(){
		return this.getSelectedRange().start;
	},

	getSelectionEnd: function(){
		return this.getSelectedRange().end;
	},

	setCaretPosition: function(pos){
		if (pos == 'end') pos = this.get('value').length;
		this.selectRange(pos, pos);
		return this;
	},

	getCaretPosition: function(){
		return this.getSelectedRange().start;
	},

	selectRange: function(start, end){
		if (this.setSelectionRange){
			this.focus();
			this.setSelectionRange(start, end);
		} else {
			var value = this.get('value');
			var diff = value.substr(start, end - start).replace(/\r/g, '').length;
			start = value.substr(0, start).replace(/\r/g, '').length;
			var range = this.createTextRange();
			range.collapse(true);
			range.moveEnd('character', start + diff);
			range.moveStart('character', start);
			range.select();
		}
		return this;
	},

	insertAtCursor: function(value, select){
		var pos = this.getSelectedRange();
		var text = this.get('value');
		this.set('value', text.substring(0, pos.start) + value + text.substring(pos.end, text.length));
		if (select !== false) this.selectRange(pos.start, pos.start + value.length);
		else this.setCaretPosition(pos.start + value.length);
		return this;
	},

	insertAroundCursor: function(options, select){
		options = Object.append({
			before: '',
			defaultMiddle: '',
			after: ''
		}, options);

		var value = this.getSelectedText() || options.defaultMiddle;
		var pos = this.getSelectedRange();
		var text = this.get('value');

		if (pos.start == pos.end){
			this.set('value', text.substring(0, pos.start) + options.before + value + options.after + text.substring(pos.end, text.length));
			this.selectRange(pos.start + options.before.length, pos.end + options.before.length + value.length);
		} else {
			var current = text.substring(pos.start, pos.end);
			this.set('value', text.substring(0, pos.start) + options.before + current + options.after + text.substring(pos.end, text.length));
			var selStart = pos.start + options.before.length;
			if (select !== false) this.selectRange(selStart, selStart + current.length);
			else this.setCaretPosition(selStart + text.length);
		}
		return this;
	}

});