/*!
 * jquery.tagcloud.js
 * A Simple Tag Cloud Plugin for JQuery
 *
 * https://github.com/addywaddy/jquery.tagcloud.js
 * created by Adam Groves
 */
(function($){

    /*global jQuery*/
    "use strict";
    
    var compareWeights = function(a, b){
        return a - b;
    };
    
    // Converts hex to an RGB array
    var toRGB = function(code){
        if (code.length === 4) {
            code = jQuery.map(/\w+/.exec(code), function(el){
                return el + el;
            }).join("");
        }
        var hex = /(\w{2})(\w{2})(\w{2})/.exec(code);
        return [parseInt(hex[1], 16), parseInt(hex[2], 16), parseInt(hex[3], 16)];
    };
    
    // Converts an RGB array to hex
    var toHex = function(ary){
        return "#" +
        jQuery.map(ary, function(i){
            var hex = i.toString(16);
            hex = (hex.length === 1) ? "0" + hex : hex;
            return hex;
        }).join("");
    };
    
    var colorIncrement = function(color, range){
        return jQuery.map(toRGB(color.end), function(n, i){
            return (n - toRGB(color.start)[i]) / range;
        });
    };
    
    var tagColor = function(color, increment, weighting){
        var rgb = jQuery.map(toRGB(color.start), function(n, i){
            var ref = Math.round(n + (increment[i] * weighting));
            if (ref > 255) {
                ref = 255;
            }
            else {
                if (ref < 0) {
                    ref = 0;
                }
            }
            return ref;
        });
        return toHex(rgb);
    };
    
    $.fn.tagcloud = function(options){
    
        var opts = $.extend({}, $.fn.tagcloud.defaults, options);
        var tagWeights = this.map(function(){
            return $(this).attr("rel");
        });
        tagWeights = jQuery.makeArray(tagWeights).sort(compareWeights);
        var lowest = tagWeights[0];
        var highest = tagWeights.pop();
        var range = highest - lowest;
        if (range === 0) {
            range = 1;
        }
        // Sizes
        var fontIncr, colorIncr;
        if (opts.size) {
            fontIncr = (opts.size.end - opts.size.start) / range;
        }
        // Colors
        if (opts.color) {
            colorIncr = colorIncrement(opts.color, range);
        }
        return this.each(function(){
            var weighting = $(this).attr("rel") - lowest;
            if (opts.size) {
                $(this).css({
                    "font-size": opts.size.start + (weighting * fontIncr) + opts.size.unit
                });
            }
            if (opts.color) {
                $(this).css({
                    "color": tagColor(opts.color, colorIncr, weighting)
                });
            }
        });
    };
    
    $.fn.tagcloud.defaults = {
        size: {
            start: 14,
            end: 18,
            unit: "pt"
        }
    };
    
})(jQuery);