(function($) {
    /**
     * Class: $.jqplot.BoxplotRenderer
     * jqPlot Plugin to draw box plots <http://en.wikipedia.org/wiki/Box_plot>.
     * 
     * To use this plugin, include the renderer js file in 
     * your source:
     * 
     * > <script type="text/javascript" src="plugins/jqplot.boxplotRenderer.js"></script>
     * 
     * Then you set the renderer in the series options on your plot:
     * 
     * > series: [{renderer:$.jqplot.BoxplotRenderer}]
     * 
     * Data should be specified like so:
     * 
     * > dat = [[sample_id, min, q1, median, q3, max], ...]
     * 
     */
    $.jqplot.BoxplotRenderer = function(){
        // subclass line renderer to make use of some of its methods.
        $.jqplot.LineRenderer.call(this);
        // prop: boxWidth
        // Default will auto calculate based on plot width and number
        // of boxes displayed.
        this.boxWidth = 'auto';
        this._boxMaxWidth = 100; // if 'auto', cap at this max
        // prop: lineWidth
        // The thickness of all lines drawn. Default is 1.5 pixels.
        this.lineWidth = 1.5;
    };
    
    $.jqplot.BoxplotRenderer.prototype = new $.jqplot.LineRenderer();
    $.jqplot.BoxplotRenderer.prototype.constructor = $.jqplot.BoxplotRenderer;
    
    // called with scope of series.
    $.jqplot.BoxplotRenderer.prototype.init = function(options) {
        this.lineWidth = options.lineWidth || this.renderer.lineWidth;
        $.jqplot.LineRenderer.prototype.init.call(this, options);
        // set the yaxis data bounds here to account for high and low values
        var db = this._yaxis._dataBounds;
        var d = this._plotData;
        for (var j=0, dj=d[j]; j<d.length; dj=d[++j]) {
            if (dj[1] < db.min || db.min == null)
                db.min = dj[1];
            if (dj[5] > db.max || db.max == null)
                db.max = dj[5];
        }
    };
    
    // called within scope of series.
    $.jqplot.BoxplotRenderer.prototype.draw = function(ctx, gd, options) {
        var d = this.data;
        var r = this.renderer;
        var xp = this._xaxis.series_u2p;
        var yp = this._yaxis.series_u2p;
        if (!options)
            options = {};
        if (!('lineWidth' in options))
            $.extend(true, options, {lineWidth: this.lineWidth});
        var boxopts = $.extend(true, {}, options, {strokeRect: true});
        var boxW = options.boxWidth || r.boxWidth;
        if (boxW == 'auto')
            boxW = Math.min(r._boxMaxWidth, 0.6 * ctx.canvas.width/d.length);
        var endW = boxW / 2; // min and max ticks are half the box width
        boxW -= this.lineWidth*2;
        ctx.save();
        if (this.show) {
            for (var i=0, di=d[i]; i<d.length; di=d[++i]) {
               var  x = xp(di[0]),
                  min = yp(di[1]),
                   q1 = yp(di[2]),
                  med = yp(di[3]),
                   q3 = yp(di[4]),
                  max = yp(di[5]);

                var endL = x - endW/2; // start (left) x coord of min/max ticks
                var endR = x + endW/2; // end (right) x coord of min/max ticks
                var medL = x - boxW/2; // start (left) x coord of median tick
                var medR = x + boxW/2; // end (right) x coord of median tick

                // draw whiskers
                r.shapeRenderer.draw(ctx, [[x, min], [x, q1]], options); 
                r.shapeRenderer.draw(ctx, [[x, q3], [x, max]], options); 

                // draw min and max ticks
                r.shapeRenderer.draw(ctx, [[endL, min], [endR, min]], options);
                r.shapeRenderer.draw(ctx, [[endL, max], [endR, max]], options);
                // median tick is full box width
                r.shapeRenderer.draw(ctx, [[medL, med], [medR, med]], options);

                // draw box
                boxH = q1 - q3;
                boxpoints = [medL, q3, boxW, boxH];
                r.shapeRenderer.draw(ctx, boxpoints, boxopts);
            }
        }
        ctx.restore();
    };  
    
    $.jqplot.BoxplotRenderer.prototype.drawShadow = function(ctx, gd, options) {
        // This is a no-op, shadows drawn with lines.
    };
    
    // called with scope of plot.
    $.jqplot.BoxplotRenderer.checkOptions = function(target, data, options) {
        // provide some sensible highlighter options by default
        hldefaults = {
            showMarker: false,
            tooltipAxes: 'y',
            yvalues: 5,
            formatString: '<table class="jqplot-highlighter">' +
                          '<tr><td>min:</td><td>%s</td></tr>' +
                          '<tr><td>q1:</td><td>%s</td></tr>' +
                          '<tr><td>med:</td><td>%s</td></tr>' +
                          '<tr><td>q3:</td><td>%s</td></tr>' +
                          '<tr><td>max:</td><td>%s</td></tr>' +
                          '</table>'
            };
        if (!options.highlighter)
            options.highlighter = {show: true};
        if (options.highlighter.show) {
            for (opt in hldefaults) {
                if (!(opt in options.highlighter)) {
                    options.highlighter[opt] = hldefaults[opt];
                }
            }
        }
    };
    
    $.jqplot.preInitHooks.push($.jqplot.BoxplotRenderer.checkOptions);
    
})(jQuery);