// This jQuery plugin implements the $.fn.highlightText method
// making it easy to highlight text within an element by wrapping
// it in a span with a given class.
//
// To use this plugin, first select the element that contains the text
// that you want to replace, then call .highlightText() on it.
// the plugin has one required parameter and two optional parameters.
//
// The plugin is always called in the same way:
// $(sel).highlightText(<parameters>);
// It accepts three parameters.
//
// The first parameter decides what text will be matched. It can be a 
// string, a regular expression in string format, a regular expression
// object, or an array of words.
//
// The second parameter is the class that will be added to the matched
// text. it is optional and can be a space delimited list of classes to
// add to the element that wraps the matched text. It is set to "highlight"
// by default.
//
// The third parameter lets you decide whether or not the plugin should
// only match full matches. It is defaulted to false, meaning it will
// match partial matches. However, this third parameter is ignored if
// the first parameter is a regular expression object.
(function($) {

    $.fn.highlightText = function() {
        // handler first parameter
        // is the first parameter a regexp?
        var re,
			hClass,
			reStr,
			argType = $.type(arguments[0]),
			defaultTagName = $.fn.highlightText.defaultTagName;

        if (argType === "regexp") {
            // first argument is a regular expression
            re = arguments[0];
        }
        // is the first parameter an array?
        else if (argType === "array") {
            // first argument is an array, generate
            // regular expression string for later use
            reStr = arguments[0].join("|");
        }
        // is the first parameter a string?
        else if (argType === "string") {
            // store string in regular expression string
            // for later use
            reStr = arguments[0];
        }
        // else, return out and do nothing because this
        // argument is required.
        else {
            return;
        }

        // the second parameter is optional, however,
        // it must be a string or boolean value. If it is 
        // a string, it will be used as the highlight class.
        // If it is a boolean value and equal to true, it 
        // will be used as the third parameter and the highlight
        // class will default to "highlight". If it is undefined,
        // the highlight class will default to "highlight" and 
        // the third parameter will default to false, allowing
        // the plugin to match partial matches.
        // ** The exception is if the first parameter is a regular
        // expression, the third parameter will be ignored.
        argType = $.type(arguments[1]);
        if (argType === "string") {
            hClass = arguments[1];
        }
        else if (argType === "boolean") {
            hClass = "highlight";
            if (reStr) {
                reStr = "\\b" + reStr + "\\b";
            }
        }
        else {
            hClass = "highlight";
        }

        if (arguments[2] && reStr) {
            reStr = reStr = "\\b" + reStr + "\\b";
        }
        console.log(reStr);
        // if re is not defined ( which means either an array or
        // string was passed as the first parameter ) create the
        // regular expression.
        if (!re) {
            re = new RegExp("(" + reStr + ")", "ig");
        }

        // iterate through each matched element
        return this.each(function() {
            // select all contents of this element
            $(this).add($(this).find("*")).contents()

            // filter to only text nodes that aren't already highlighted
	        .filter(function() {
	            return this.nodeType === 3 && $(this).closest("." + hClass).length === 0;
	        })

            // loop through each text node
			.each(function() {
			    var output;
			    output = this.nodeValue
	                .replace(re, "<" + defaultTagName + " class='" + hClass + "'>$1</" + defaultTagName + ">");
			    if (output !== this.nodeValue) {
			        $(this).wrap("<p></p>").parent()
	                    .html(output).contents().unwrap();
			    }
			});
        });
    };

    $.fn.highlightText.defaultTagName = "span";

})(jQuery);