/*!
 * Copyright (c) 2011 Averta.net
 * Licensed under the MIT license.
 *
 * @author Morteza Faghih Shojaei
 * @version 1.0b
 */

 var FarsiStyle = (function () {
 
	var api = function(){
		return api.convert.apply(null, arguments);
	}
 
	// Char map 
	var orginal_chars  = 'ئ ء ي ی ه و ن م ل گ ك ک ق ف غ ع ظ ط ض ص ش س ژ ز ر ذ د خ ح چ ج ث ت پ ب ا أ آ';
	var isolated_chars = 'ﺉ ﺀ ﻯ ﻯ ﻩ ﻭ ﻥ ﻡ ﻝ ﮒ ﮎ ﮎ ﻕ ﻑ ﻍ ﻉ ﻅ ﻁ ﺽ ﺹ ﺵ ﺱ ﮊ ﺯ ﺭ ﺫ ﺩ ﺥ ﺡ ﭺ ﺝ ﺙ ﺕ ﭖ ﺏ ﺍ ﺍ ﺁ';
	var initial_chars  = 'ﺋ ﺀ ﻳ ﻳ ﻫ ﻭ ﻧ ﻣ ﻟ ﮔ ﻛ ﻛ ﻗ ﻓ ﻏ ﻋ ﻇ ﻃ ﺿ ﺻ ﺷ ﺳ ﮊ ﺯ ﺭ ﺫ ﺩ ﺧ ﺣ ﭼ ﺟ ﺛ ﺗ ﭘ ﺑ ﺍ ﺋ ﺁ';
	var middle_chars   = 'ﺌ ﺀ ﻴ ﻴ ﻬ ﻮ ﻨ ﻤ ﻠ ﮕ ﻜ ﻜ ﻘ ﻔ ﻐ ﻌ ﻈ ﻄ ﻀ ﺼ ﺸ ﺴ ﮋ ﺰ ﺮ ﺬ ﺪ ﺨ ﺤ ﭽ ﺠ ﺜ ﺘ ﭙ ﺒ ﺎ ﺌ ﺁ';
	var final_chars    = 'ﺊ ﺀ ﻰ ﻰ ﻪ ﻮ ﻦ ﻢ ﻞ ﮓ ﮏ ﮏ ﻖ ﻒ ﻎ ﻊ ﻆ ﻂ ﺾ ﺺ ﺶ ﺲ ﮋ ﺰ ﺮ ﺬ ﺪ ﺦ ﺢ ﭻ ﺞ ﺚ ﺖ ﭗ ﺐ ﺎ ﺄ ﺁ';

	// replace sp_chars with sp_chars_replace on the same char index
	var sp_chars =         '[](){}<>؟،۰۱۲۳۴۵۶۷۸۹٪٫»«""';
	var sp_chars_replace = '][)(}{><?,0123456789%,][""';
	
	// odd bidi characters 
	var farsi_chars = 'ئحكيآابپتثجچهخدذرزژسشصضطظعغفقکگلمنوهیأ';
	
	// all of characters that have initial mode
	var left_join_chars = 'ئحكيبپتثجچهخسشصضطظعغفقکگلمنهی';
	
	// number characters
	var num_chars = '0123456789۰۱۲۳۴۵۶۷۸۹';
	
	var sp_num_chars = '٫،٫,:.,';
	
	var common_chars = ' /!@#$%&*()_+=-.,\"\';:{}|[]?<>÷؟،\r';
	
	// remove these characters in converted text 
	var remove_chars = 'ـ\nًٌٍَُِّ';
	var input_str;
	
	function getChar(org_char_index)  {
		
		var right_char = charAt(org_char_index - 1);
		var char = charAt(org_char_index);
		var left_char = charAt(org_char_index + 1);
		
		if (isFarsi(char)) {
			return checkLeftChar(char , left_char , !(right_char == '' || left_join_chars.indexOf(right_char) == -1) );
		} else if (sp_chars.indexOf(char) != -1) { 
			return getSpChars(char);
		} else {			
			return char;
		}
		
		return '';
		
	}
	
	 function checkLeftChar(char , left_char , join_to_right) {
		if (!(left_char == '' || !isFarsi(left_char))) {
			return (join_to_right) ? getFSChar(char , 'middle') : getFSChar(char , 'initial'); 
		}else {
			return (join_to_right) ? getFSChar(char , 'final') : getFSChar(char , 'isolated'); 
		}
		return '';
	}
	
	 function getSpChars(char) {
		return sp_chars_replace.charAt(sp_chars.indexOf(char));
	}
	
	 function getFSChar(org_char , type) {
		
		var index = orginal_chars.indexOf(org_char);
		
		switch(type) {
			case 'isolated':
				return isolated_chars.charAt(index);
				break;
			case 'initial':
				return initial_chars.charAt(index);
				break;
			case 'middle':
				return middle_chars.charAt(index);
				break;
			case 'final':
				return final_chars.charAt(index);
				break;
		}
		
		return '';
	}
	
	function isFarsi(char) {
		return farsi_chars.indexOf(char) != -1;
	}
	
	 function charAt(index) {
		return input_str.charAt(index);
	}
	
 	function convert(text) {
		var return_str = '';
		var en_chars_buffer = '';
		var common_chars_reverse_buffer = '';
		var num_chars_buffer = '';
		var num_self_buffer = '';
		var char;
		var org_char;
		
		input_str = text;
		
		for (var i = 0 ; i < input_str.length; i++) {
			
			if (remove_chars.indexOf(charAt(i + 1)) != -1) {
				input_str = input_str.slice(0 , i + 1) + input_str.slice(i + 2);
			}
			
			char = getChar(i);
			org_char = charAt(i);
			
			if (isFarsi(org_char)) {
				if(common_chars_reverse_buffer == ''){
					return_str = en_chars_buffer + return_str;
				}else {
					common_chars_reverse_buffer = '';
				}	
				return_str = num_chars_buffer + return_str;
				num_chars_buffer = '';
				en_chars_buffer = '';
				return_str = char + return_str;
			}else if(common_chars.indexOf(org_char) != -1) {
				if (common_chars_reverse_buffer == '') {
					return_str = en_chars_buffer + return_str;
				}
				return_str = num_chars_buffer + return_str;
				num_chars_buffer = '';
				return_str = char + return_str;
				common_chars_reverse_buffer += char;
			}else if(num_chars.indexOf(org_char) != -1 && en_chars_buffer == ''){
				if (common_chars_reverse_buffer.length == 1 && sp_num_chars.indexOf(common_chars_reverse_buffer) != -1) {
					return_str = return_str.slice(num_self_buffer.length);
					num_chars_buffer = num_self_buffer+ common_chars_reverse_buffer + char; 
					num_self_buffer = '';
				}else {
					num_self_buffer += char;
					num_chars_buffer += char;
				}
				common_chars_reverse_buffer = '';
			}else {
				if (common_chars_reverse_buffer != '' && en_chars_buffer != '') {
					return_str = return_str.slice((common_chars_reverse_buffer.length + en_chars_buffer.length));
					en_chars_buffer += common_chars_reverse_buffer + char;
					common_chars_reverse_buffer = '';
				}else if(common_chars_reverse_buffer != '') {
					common_chars_reverse_buffer = '';
					en_chars_buffer = char;
				}else {
					en_chars_buffer += char;
				}
			}
		}
		return return_str + ((common_chars_reverse_buffer == '')? en_chars_buffer : '') +  num_chars_buffer;
	}
		
	function getOrginalText() {
		return input_str;
	}
	
	api.convert = function(text){
		return convert(text + ' ').slice(1);
	}
	
	return api;	
})();	

var Bifon = (function () {
	
	var api = function(){
		return api.covert.apply(null, arguments);
	}
	
	api.convert = function(element){
		if(typeof(element.textContent) != "undefined")
			element.textContent = FarsiStyle.convert(element.textContent);
		else
			element.innerText = FarsiStyle.convert(element.innerText);
	}
	
	return api;
})();