/*
* 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 characters | #words words'
        };
        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);