(function($, block) {

// a simple barchart example
block.fn.barchart = function(config) {
    var options = $.extend({
    	series : { "serie1":{
        	data: {"January": 10, "February": 8, "March": 4, "April": 13, "May": 20, "June": 9},
        	label: "serie 1",
        	bars: {
                	show: true,
                	barWidth: 0.2,
                	align: "left"
            	}
       	 
    	},  "serie2":{
        	data: {"January": 10, "February": 8, "March": 4, "April": 13, "May": 20, "June": 9},
        	label: "series 2",
        	bars: {
                	show: true,
                	barWidth: 0.2,
                	align: "center"
            	}
    	},  "serie3":{
        	data: {"January": 10, "February": 8, "March": 4, "April": 13, "May": 20, "June": 9},
        	label: "series 3",
        	bars: {
                	show: true,
                	barWidth: 0.2,
                	align: "right"
            	}
    	}}
    }, config);

    var bar_init = {
            xaxis: {
                mode: "categories",
                tickLength: 0
            }
	}

    var bardata_series = options.series;

    var translate_bar = function() {
        var result = [];
	for(var k in bardata_series) {
	    if (bardata_series.hasOwnProperty(k)) {
		var newserie = jQuery.extend({}, bardata_series[k]);
        	var newdata = [];
		var data = newserie.data;
		for(var l in data) {
	    	    if (data.hasOwnProperty(l)) {
			newdata.push([l,data[l]]);
		    }
		}
		newserie.data = newdata;
		result.push(newserie);
	    }
	}
	return result;
    }

    var plot = $.plot(this.$element, translate_bar(), bar_init);

    var addbar = function(serie_label, category, value) {
	var data = bardata_series[serie_label].data;
	if (data.hasOwnProperty(category))
		data[category] = (data[category] + value);
	else
		data[category] = value;
	redraw();
    }

    var setbar = function(serie_label, category, value) {
	var data = bardata_series[serie_label].data;
	data[category] = value;
	redraw();
    }

    var redraw = function() {
        plot.setData(translate_bar());
	plot.setupGrid();
        plot.draw();
    }

    var reset = function() {
	for(var k in bardata_series) {
	    if (bardata_series.hasOwnProperty(k)) {
		bardata_series[k].data = {};
	    }
	}
    }

    this.actions({
        'set': function(e, message) {
		setbar(message.series,message.value[0],message.value[1]);
        },
        'add': function(e, message) {
		addbar(message.series,message.value[0],message.value[1]);
        },
        'reset': function(e, message) {
		reset();
	}
    });
    // return element to allow further work
    return this.$element;
}

})(jQuery, block);