/*
 * jQuery Textarea Characters Counter Plugin v 2.0
 * Examples and documentation at: http://roy-jin.appspot.com/jsp/textareaCounter.jsp
 * Copyright (c) 2010 Roy Jin
 * Version: 2.0 (11-JUN-2010)
 * Dual licensed under the MIT and GPL licenses:
 * http://www.opensource.org/licenses/mit-license.php
 * http://www.gnu.org/licenses/gpl.html
 * Requires: jQuery v1.4.2 or later
 */
(function($){  
    $.fn.textareaCount = function(options, fn) {   
        var defaults = {  
            maxCharacterSize: -1,  
            originalStyle: 'originalTextareaInfo',
            warningStyle: 'warningTextareaInfo',  
            warningNumber: 20,
            displayFormat: '#input caracteres | #words palabras'
        };  
        var options = $.extend(defaults, options);
        
        var container = $(this);
        
        $("<div class='charleft'>&nbsp;</div>").insertAfter(container);
        
        //create charleft css
        var charLeftCss = {
            'width' : container.width()
        };
        
        var charLeftInfo = getNextCharLeftInformation(container);
        charLeftInfo.addClass(options.originalStyle);
        charLeftInfo.css(charLeftCss);
        
        var numInput = 0;
        var maxCharacters = options.maxCharacterSize;
        var numLeft = 0;
        var numWords = 0;
                
        container.bind('keyup', function(event){limitTextAreaByCharacterCount();})
                 .bind('mouseover', function(event){setTimeout(function(){limitTextAreaByCharacterCount();}, 10);})
                 .bind('paste', function(event){setTimeout(function(){limitTextAreaByCharacterCount();}, 10);});
        
        function limitTextAreaByCharacterCount(){
            charLeftInfo.html(countByCharacters());
            //function call back
            if(typeof fn != 'undefined'){
                fn.call(this, getInfo());
            }
            return true;
        }
        
        function countByCharacters(){
            var content = container.val();
            var contentLength = content.length;
            
            //Start Cut
            if(options.maxCharacterSize > 0){
                //If copied content is already more than maxCharacterSize, chop it to maxCharacterSize.
                if(contentLength >= options.maxCharacterSize) {
                    content = content.substring(0, options.maxCharacterSize);                 
                }
                
                var newlineCount = getNewlineCount(content);
                
                // newlineCount new line character. For windows, it occupies 2 characters
                var systemmaxCharacterSize = options.maxCharacterSize - newlineCount;
                if (!isWin()){
                     systemmaxCharacterSize = options.maxCharacterSize
                }
                if(contentLength > systemmaxCharacterSize){
                    //avoid scroll bar moving
                    var originalScrollTopPosition = this.scrollTop;
                    container.val(content.substring(0, systemmaxCharacterSize));
                    this.scrollTop = originalScrollTopPosition;
                }
                charLeftInfo.removeClass(options.warningStyle);
                if(systemmaxCharacterSize - contentLength <= options.warningNumber){
                    charLeftInfo.addClass(options.warningStyle);
                }
                
                numInput = container.val().length + newlineCount;
                if(!isWin()){
                    numInput = container.val().length;
                }
            
                numWords = countWord(getCleanedWordString(container.val()));
                
                numLeft = maxCharacters - numInput;
            } else {
                //normal count, no cut
                var newlineCount = getNewlineCount(content);
                numInput = container.val().length + newlineCount;
                if(!isWin()){
                    numInput = container.val().length;
                }
                numWords = countWord(getCleanedWordString(container.val()));
            }
            
            return formatDisplayInfo();
        }
        
        function formatDisplayInfo(){
            var format = options.displayFormat;
            format = format.replace('#input', numInput);
            format = format.replace('#words', numWords);
            //When maxCharacters <= 0, #max, #left cannot be substituted.
            if(maxCharacters > 0){
                format = format.replace('#max', maxCharacters);
                format = format.replace('#left', numLeft);
            }
            return format;
        }
        
        function getInfo(){
            var info = {
                input: numInput,
                max: maxCharacters,
                left: numLeft,
                words: numWords
            };
            return info;
        }
        
        function getNextCharLeftInformation(container){
                return container.next('.charleft');
        }
        
        function isWin(){
            var strOS = navigator.appVersion;
            if (strOS.toLowerCase().indexOf('win') != -1){
                return true;
            }
            return false;
        }
        
        function getNewlineCount(content){
            var newlineCount = 0;
            for(var i=0; i<content.length;i++){
                if(content.charAt(i) == '\n'){
                    newlineCount++;
                }
            }
            return newlineCount;
        }
        
        function getCleanedWordString(content){
            var fullStr = content + " ";
            var initial_whitespace_rExp = /^[^A-Za-z0-9]+/gi;
            var left_trimmedStr = fullStr.replace(initial_whitespace_rExp, "");
            var non_alphanumerics_rExp = rExp = /[^A-Za-z0-9]+/gi;
            var cleanedStr = left_trimmedStr.replace(non_alphanumerics_rExp, " ");
            var splitString = cleanedStr.split(" ");
            return splitString;
        }
        
        function countWord(cleanedWordString){
            var word_count = cleanedWordString.length-1;
            return word_count;
        }
    };  
})(jQuery);