/**
 * @package     Joomla.JavaScript
 * @copyright   Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

// Only define the Joomla namespace if not defined.
if (typeof(Joomla) === 'undefined') {
    var Joomla = {};
}

Joomla.Highlighter = function(_options){
    var $, words, options = {
        autoUnhighlight: true,
        caseSensitive: false,
        startElement: false,
        endElement: false,
        elements: [],
        className: 'highlight',
        onlyWords: true,
        tag: 'span'
    },

    highlight = function (words) {
        if (words.constructor === String) {
            words = [words];
        }
        if (options.autoUnhighlight) {
            unhighlight(words);
        }
        var pattern = options.onlyWords ? '\b' + pattern + '\b' : '(' + words.join('\\b|\\b') + ')',
        regex = new RegExp(pattern, options.caseSensitive ? '' : 'i');
        options.elements.map(function(el){
            recurse(el, regex, options.className);
        });
        return this;
    },

    unhighlight = function (words) {
        if (words.constructor === String) {
            words = [words];
        }

        var $elements, tn;
        words.map(function(word){
            word = (options.caseSensitive ? word : word.toUpperCase());
            if (words[word]) {
                $elements = $(words[word]);
                $elements.removeClass();
                $elements.each(function (index, el) {
                    tn = document.createTextNode($(el).text());
                    el.parentNode.replaceChild(tn, el);
                });
            }
        });
        return this;
    },

    recurse = function (node, regex, klass) {
        if (node.nodeType === 3) {
            var match = node.nodeValue.match(regex), highlight, $highlight, wordNode, wordClone, comparer, i;
            if (match) {
                highlight = document.createElement(options.tag);
                $highlight = $(highlight);
                $highlight.addClass(klass);
                wordNode = node.splitText(match.index);
                wordNode.splitText(match[0].length);
                wordClone = wordNode.cloneNode(true);
                $highlight.append(wordClone);
                $(wordNode).replaceWith(highlight)
                $highlight.attr('rel', $highlight.text());
                comparer = $highlight.text()
                if (!options.caseSensitive) {
                    comparer = $highlight.text().toUpperCase();
                }
                if (!words[comparer]) {
                    words[comparer] = [];
                }
                words[comparer].push(highlight);
                return 1;
            }
        } else if ((node.nodeType === 1 && node.childNodes) && !/(script|style|textarea|iframe)/i.test(node.tagName) && !(node.tagName === options.tag.toUpperCase() && node.className === klass)) {
            for (i = 0; i < node.childNodes.length; i++) {
                i += recurse(node.childNodes[i], regex, klass);
            }
        }
        return 0;
    },

    getElements = function ($start, $end) {
        var $next = $start.next();
        if ($next.attr('id') !== $end.attr('id')) {
            options.elements.push($next.get(0));
            getElements($next, $end);
        }
    },

    initialize = function(_options) {
        $ = jQuery.noConflict();
        $.extend(options, _options);
        getElements($(options.startElement), $(options.endElement));
        words = [];
    };

    initialize(_options);

    return {
        highlight: highlight,
        unhighlight : unhighlight
    };
}
