jquery.flot.js

/* Javascript plotting library for jQuery, v. 0.6.
 *
 * Released under the MIT license by IOLA, December 2007.
 *
 */

// first an inline dependency, jquery.colorhelpers.js, we inline it here
// for convenience

/* Plugin for jQuery for working with colors.
 * 
 * Version 1.0.
 * 
 * Inspiration from jQuery color animation plugin by John Resig.
 *
 * Released under the MIT license by Ole Laursen, October 2009.
 *
 * Examples:
 *
 *   $.color.parse("#fff").scale('rgb', 0.25).add('a', -0.5).toString()
 *   var c = $.color.extract($("#mydiv"), 'background-color');
 *   console.log(c.r, c.g, c.b, c.a);
 *   $.color.make(100, 50, 25, 0.4).toString() // returns "rgba(100,50,25,0.4)"
 *
 * Note that .scale() and .add() work in-place instead of returning
 * new objects.
 */ 
(function(){jQuery.color={};jQuery.color.make=function(E,D,B,C){var F={};F.r=E||0;F.g=D||0;F.b=B||0;F.a=C!=null?C:1;F.add=function(I,H){for(var G=0;G<I.length;++G){F[I.charAt(G)]+=H}return F.normalize()};F.scale=function(I,H){for(var G=0;G<I.length;++G){F[I.charAt(G)]*=H}return F.normalize()};F.toString=function(){if(F.a>=1){return"rgb("+[F.r,F.g,F.b].join(",")+")"}else{return"rgba("+[F.r,F.g,F.b,F.a].join(",")+")"}};F.normalize=function(){function G(I,J,H){return J<I?I:(J>H?H:J)}F.r=G(0,parseInt(F.r),255);F.g=G(0,parseInt(F.g),255);F.b=G(0,parseInt(F.b),255);F.a=G(0,F.a,1);return F};F.clone=function(){return jQuery.color.make(F.r,F.b,F.g,F.a)};return F.normalize()};jQuery.color.extract=function(C,B){var D;do{D=C.css(B).toLowerCase();if(D!=""&&D!="transparent"){break}C=C.parent()}while(!jQuery.nodeName(C.get(0),"body"));if(D=="rgba(0, 0, 0, 0)"){D="transparent"}return jQuery.color.parse(D)};jQuery.color.parse=function(E){var D,B=jQuery.color.make;if(D=/rgb\(\s*([0-9]{1,3})\s*,\s*([0-9]{1,3})\s*,\s*([0-9]{1,3})\s*\)/.exec(E)){return B(parseInt(D[1],10),parseInt(D[2],10),parseInt(D[3],10))}if(D=/rgba\(\s*([0-9]{1,3})\s*,\s*([0-9]{1,3})\s*,\s*([0-9]{1,3})\s*,\s*([0-9]+(?:\.[0-9]+)?)\s*\)/.exec(E)){return B(parseInt(D[1],10),parseInt(D[2],10),parseInt(D[3],10),parseFloat(D[4]))}if(D=/rgb\(\s*([0-9]+(?:\.[0-9]+)?)\%\s*,\s*([0-9]+(?:\.[0-9]+)?)\%\s*,\s*([0-9]+(?:\.[0-9]+)?)\%\s*\)/.exec(E)){return B(parseFloat(D[1])*2.55,parseFloat(D[2])*2.55,parseFloat(D[3])*2.55)}if(D=/rgba\(\s*([0-9]+(?:\.[0-9]+)?)\%\s*,\s*([0-9]+(?:\.[0-9]+)?)\%\s*,\s*([0-9]+(?:\.[0-9]+)?)\%\s*,\s*([0-9]+(?:\.[0-9]+)?)\s*\)/.exec(E)){return B(parseFloat(D[1])*2.55,parseFloat(D[2])*2.55,parseFloat(D[3])*2.55,parseFloat(D[4]))}if(D=/#([a-fA-F0-9]{2})([a-fA-F0-9]{2})([a-fA-F0-9]{2})/.exec(E)){return B(parseInt(D[1],16),parseInt(D[2],16),parseInt(D[3],16))}if(D=/#([a-fA-F0-9])([a-fA-F0-9])([a-fA-F0-9])/.exec(E)){return B(parseInt(D[1]+D[1],16),parseInt(D[2]+D[2],16),parseInt(D[3]+D[3],16))}var C=jQuery.trim(E).toLowerCase();if(C=="transparent"){return B(255,255,255,0)}else{D=A[C];return B(D[0],D[1],D[2])}};var A={aqua:[0,255,255],azure:[240,255,255],beige:[245,245,220],black:[0,0,0],blue:[0,0,255],brown:[165,42,42],cyan:[0,255,255],darkblue:[0,0,139],darkcyan:[0,139,139],darkgrey:[169,169,169],darkgreen:[0,100,0],darkkhaki:[189,183,107],darkmagenta:[139,0,139],darkolivegreen:[85,107,47],darkorange:[255,140,0],darkorchid:[153,50,204],darkred:[139,0,0],darksalmon:[233,150,122],darkviolet:[148,0,211],fuchsia:[255,0,255],gold:[255,215,0],green:[0,128,0],indigo:[75,0,130],khaki:[240,230,140],lightblue:[173,216,230],lightcyan:[224,255,255],lightgreen:[144,238,144],lightgrey:[211,211,211],lightpink:[255,182,193],lightyellow:[255,255,224],lime:[0,255,0],magenta:[255,0,255],maroon:[128,0,0],navy:[0,0,128],olive:[128,128,0],orange:[255,165,0],pink:[255,192,203],purple:[128,0,128],violet:[128,0,128],red:[255,0,0],silver:[192,192,192],white:[255,255,255],yellow:[255,255,0]}})();

// the actual Flot code
(function($) {
    function Plot(placeholder, data_, options_, plugins) {
        // data is on the form:
        //   [ series1, series2 ... ]
        // where series is either just the data as [ [x1, y1], [x2, y2], ... ]
        // or { data: [ [x1, y1], [x2, y2], ... ], label: "some label", ... }
        
        var series = [],
            options = {
                // the color theme used for graphs
                colors: ["#edc240", "#afd8f8", "#cb4b4b", "#4da74d", "#9440ed"],
                legend: {
                    show: true,
                    noColumns: 1, // number of colums in legend table
                    labelFormatter: null, // fn: string -> string
                    labelBoxBorderColor: "#ccc", // border color for the little label boxes
                    container: null, // container (as jQuery object) to put legend in, null means default on top of graph
                    position: "ne", // position of default legend container within plot
                    margin: 5, // distance from grid edge to default legend container within plot
                    backgroundColor: null, // null means auto-detect
                    backgroundOpacity: 0.85 // set to 0 to avoid background
                },
                xaxis: {
                    mode: null, // null or "time"
                    transform: null, // null or f: number -> number to transform axis
                    inverseTransform: null, // if transform is set, this should be the inverse function
                    min: null, // min. value to show, null means set automatically
                    max: null, // max. value to show, null means set automatically
                    autoscaleMargin: null, // margin in % to add if auto-setting min/max
                    ticks: null, // either [1, 3] or [[1, "a"], 3] or (fn: axis info -> ticks) or app. number of ticks for auto-ticks
                    tickFormatter: null, // fn: number -> string
                    labelWidth: null, // size of tick labels in pixels
                    labelHeight: null,
                    
                    // mode specific options
                    tickDecimals: null, // no. of decimals, null means auto
                    tickSize: null, // number or [number, "unit"]
                    minTickSize: null, // number or [number, "unit"]
                    monthNames: null, // list of names of months
                    timeformat: null, // format string to use
                    twelveHourClock: false // 12 or 24 time in time mode
                },
                yaxis: {
                    autoscaleMargin: 0.02
                },
                x2axis: {
                    autoscaleMargin: null
                },
                y2axis: {
                    autoscaleMargin: 0.02
                },
                series: {
                    points: {
                        show: false,
                        radius: 3,
                        lineWidth: 2, // in pixels
                        fill: true,
                        fillColor: "#ffffff"
                    },
                    lines: {
                        // we don't put in show: false so we can see
                        // whether lines were actively disabled 
                        lineWidth: 2, // in pixels
                        fill: false,
                        fillColor: null,
                        steps: false
                    },
                    bars: {
                        show: false,
                        lineWidth: 2, // in pixels
                        barWidth: 1, // in units of the x axis
                        fill: true,
                        fillColor: null,
                        align: "left", // or "center" 
                        horizontal: false
                    },
                    shadowSize: 3
                },
                grid: {
                    show: true,
                    aboveData: false,
                    color: "#545454", // primary color used for outline and labels
                    backgroundColor: null, // null for transparent, else color
                    tickColor: "rgba(0,0,0,0.15)", // color used for the ticks
                    labelMargin: 5, // in pixels
                    borderWidth: 2, // in pixels
                    borderColor: null, // set if different from the grid color
                    markings: null, // array of ranges or fn: axes -> array of ranges
                    markingsColor: "#f4f4f4",
                    markingsLineWidth: 2,
                    // interactive stuff
                    clickable: false,
                    hoverable: false,
                    autoHighlight: true, // highlight in case mouse is near
                    mouseActiveRadius: 10 // how far the mouse can be away to activate an item
                },
                hooks: {}
            },
        canvas = null,      // the canvas for the plot itself
        overlay = null,     // canvas for interactive stuff on top of plot
        eventHolder = null, // jQuery object that events should be bound to
        ctx = null, octx = null,
        axes = { xaxis: {}, yaxis: {}, x2axis: {}, y2axis: {} },
        plotOffset = { left: 0, right: 0, top: 0, bottom: 0},
        canvasWidth = 0, canvasHeight = 0,
        plotWidth = 0, plotHeight = 0,
        hooks = {
            processOptions: [],
            processRawData: [],
            processDatapoints: [],
            draw: [],
            bindEvents: [],
            drawOverlay: []
        },
        plot = this;

        // public functions
        // plot.getOverlay = function () {return overlay}
        plot.setData = setData;
        plot.setupGrid = setupGrid;
        plot.draw = draw;
        plot.getPlaceholder = function() { return placeholder; };
        plot.getCanvas = function() { return canvas; };
        plot.getPlotOffset = function() { return plotOffset; };
        plot.width = function () { return plotWidth; };
        plot.height = function () { return plotHeight; };
        plot.offset = function () {
            var o = eventHolder.offset();
            o.left += plotOffset.left;
            o.top += plotOffset.top;
            return o;
        };
        plot.getData = function() { return series; };
        plot.getAxes = function() { return axes; };
        plot.getOptions = function() { return options; };
        plot.highlight = highlight;
        plot.unhighlight = unhighlight;
        plot.triggerRedrawOverlay = triggerRedrawOverlay;
        plot.pointOffset = function(point) {
            return { left: parseInt(axisSpecToRealAxis(point, "xaxis").p2c(+point.x) + plotOffset.left),
                     top: parseInt(axisSpecToRealAxis(point, "yaxis").p2c(+point.y) + plotOffset.top) };
        };
        

        // public attributes
        plot.hooks = hooks;
        
        // initialize
        initPlugins(plot);
        parseOptions(options_);
        constructCanvas();
        setData(data_);
        setupGrid();
        draw();
        bindEvents();


        function executeHooks(hook, args) {
            args = [plot].concat(args);
            for (var i = 0; i < hook.length; ++i)
                hook[i].apply(this, args);
        }

        function initPlugins() {
            for (var i = 0; i < plugins.length; ++i) {
                var p = plugins[i];
                p.init(plot);
                if (p.options)
                    $.extend(true, options, p.options);
            }
        }
        
        function parseOptions(opts) {
            $.extend(true, options, opts);
            if (options.grid.borderColor == null)
                options.grid.borderColor = options.grid.color;
            // backwards compatibility, to be removed in future
            if (options.xaxis.noTicks && options.xaxis.ticks == null)
                options.xaxis.ticks = options.xaxis.noTicks;
            if (options.yaxis.noTicks && options.yaxis.ticks == null)
                options.yaxis.ticks = options.yaxis.noTicks;
            if (options.grid.coloredAreas)
                options.grid.markings = options.grid.coloredAreas;
            if (options.grid.coloredAreasColor)
                options.grid.markingsColor = options.grid.coloredAreasColor;
            if (options.lines)
                $.extend(true, options.series.lines, options.lines);
            if (options.points)
                $.extend(true, options.series.points, options.points);
            if (options.bars)
                $.extend(true, options.series.bars, options.bars);
            if (options.shadowSize)
                options.series.shadowSize = options.shadowSize;

            for (var n in hooks)
                if (options.hooks[n] && options.hooks[n].length)
                    hooks[n] = hooks[n].concat(options.hooks[n]);

            executeHooks(hooks.processOptions, [options]);
        }

        function setData(d) {
            series = parseData(d);
            fillInSeriesOptions();
            processData();
        }
        
        function parseData(d) {
            var res = [];
            for (var i = 0; i < d.length; ++i) {
                var s = $.extend(true, {}, options.series);

                if (d[i].data) {
                    s.data = d[i].data; // move the data instead of deep-copy
                    delete d[i].data;

                    $.extend(true, s, d[i]);

                    d[i].data = s.data;
                }
                else
                    s.data = d[i];
                res.push(s);
            }

            return res;
        }
        
        function axisSpecToRealAxis(obj, attr) {
            var a = obj[attr];
            if (!a || a == 1)
                return axes[attr];
            if (typeof a == "number")
                return axes[attr.charAt(0) + a + attr.slice(1)];
            return a; // assume it's OK
        }
        
        function fillInSeriesOptions() {
            var i;
            
            // collect what we already got of colors
            var neededColors = series.length,
                usedColors = [],
                assignedColors = [];
            for (i = 0; i < series.length; ++i) {
                var sc = series[i].color;
                if (sc != null) {
                    --neededColors;
                    if (typeof sc == "number")
                        assignedColors.push(sc);
                    else
                        usedColors.push($.color.parse(series[i].color));
                }
            }
            
            // we might need to generate more colors if higher indices
            // are assigned
            for (i = 0; i < assignedColors.length; ++i) {
                neededColors = Math.max(neededColors, assignedColors[i] + 1);
            }

            // produce colors as needed
            var colors = [], variation = 0;
            i = 0;
            while (colors.length < neededColors) {
                var c;
                if (options.colors.length == i) // check degenerate case
                    c = $.color.make(100, 100, 100);
                else
                    c = $.color.parse(options.colors[i]);

                // vary color if needed
                var sign = variation % 2 == 1 ? -1 : 1;
                c.scale('rgb', 1 + sign * Math.ceil(variation / 2) * 0.2)

                // FIXME: if we're getting to close to something else,
                // we should probably skip this one
                colors.push(c);
                
                ++i;
                if (i >= options.colors.length) {
                    i = 0;
                    ++variation;
                }
            }

            // fill in the options
            var colori = 0, s;
            for (i = 0; i < series.length; ++i) {
                s = series[i];
                
                // assign colors
                if (s.color == null) {
                    s.color = colors[colori].toString();
                    ++colori;
                }
                else if (typeof s.color == "number")
                    s.color = colors[s.color].toString();

                // turn on lines automatically in case nothing is set
                if (s.lines.show == null) {
                    var v, show = true;
                    for (v in s)
                        if (s[v] && s[v].show) {
                            show = false;
                            break;
                        }
                    if (show)
                        s.lines.show = true;
                }

                // setup axes
                s.xaxis = axisSpecToRealAxis(s, "xaxis");
                s.yaxis = axisSpecToRealAxis(s, "yaxis");
            }
        }
        
        function processData() {
            var topSentry = Number.POSITIVE_INFINITY,
                bottomSentry = Number.NEGATIVE_INFINITY,
                i, j, k, m, length,
                s, points, ps, x, y, axis, val, f, p;

            for (axis in axes) {
                axes[axis].datamin = topSentry;
                axes[axis].datamax = bottomSentry;
                axes[axis].used = false;
            }

            function updateAxis(axis, min, max) {
                if (min < axis.datamin)
                    axis.datamin = min;
                if (max > axis.datamax)
                    axis.datamax = max;
            }

            for (i = 0; i < series.length; ++i) {
                s = series[i];
                s.datapoints = { points: [] };
                
                executeHooks(hooks.processRawData, [ s, s.data, s.datapoints ]);
            }
            
            // first pass: clean and copy data
            for (i = 0; i < series.length; ++i) {
                s = series[i];

                var data = s.data, format = s.datapoints.format;

                if (!format) {
                    format = [];
                    // find out how to copy
                    format.push({ x: true, number: true, required: true });
                    format.push({ y: true, number: true, required: true });

                    if (s.bars.show || (s.lines.show && s.lines.fill)) {
                        format.push({ y: true, number: true, required: false, defaultValue: 0 });
                        if (s.bars.horizontal) {
                            delete format[format.length - 1].y;
                            format[format.length - 1].x = true;
                        }
                    }
                    
                    s.datapoints.format = format;
                }

                if (s.datapoints.pointsize != null)
                    continue; // already filled in

                if (s.datapoints.pointsize == null)
                    s.datapoints.pointsize = format.length;
                
                ps = s.datapoints.pointsize;
                points = s.datapoints.points;

                insertSteps = s.lines.show && s.lines.steps;
                s.xaxis.used = s.yaxis.used = true;
                
                for (j = k = 0; j < data.length; ++j, k += ps) {
                    p = data[j];

                    var nullify = p == null;
                    if (!nullify) {
                        for (m = 0; m < ps; ++m) {
                            val = p[m];
                            f = format[m];

                            if (f) {
                                if (f.number && val != null) {
                                    val = +val; // convert to number
                                    if (isNaN(val))
                                        val = null;
                                }

                                if (val == null) {
                                    if (f.required)
                                        nullify = true;
                                    
                                    if (f.defaultValue != null)
                                        val = f.defaultValue;
                                }
                            }
                            
                            points[k + m] = val;
                        }
                    }
                    
                    if (nullify) {
                        for (m = 0; m < ps; ++m) {
                            val = points[k + m];
                            if (val != null) {
                                f = format[m];
                                // extract min/max info
                                if (f.x)
                                    updateAxis(s.xaxis, val, val);
                                if (f.y)
                                    updateAxis(s.yaxis, val, val);
                            }
                            points[k + m] = null;
                        }
                    }
                    else {
                        // a little bit of line specific stuff that
                        // perhaps shouldn't be here, but lacking
                        // better means...
                        if (insertSteps && k > 0
                            && points[k - ps] != null
                            && points[k - ps] != points[k]
                            && points[k - ps + 1] != points[k + 1]) {
                            // copy the point to make room for a middle point
                            for (m = 0; m < ps; ++m)
                                points[k + ps + m] = points[k + m];

                            // middle point has same y
                            points[k + 1] = points[k - ps + 1];

                            // we've added a point, better reflect that
                            k += ps;
                        }
                    }
                }
            }

            // give the hooks a chance to run
            for (i = 0; i < series.length; ++i) {
                s = series[i];
                
                executeHooks(hooks.processDatapoints, [ s, s.datapoints]);
            }

            // second pass: find datamax/datamin for auto-scaling
            for (i = 0; i < series.length; ++i) {
                s = series[i];
                points = s.datapoints.points,
                ps = s.datapoints.pointsize;

                var xmin = topSentry, ymin = topSentry,
                    xmax = bottomSentry, ymax = bottomSentry;
                
                for (j = 0; j < points.length; j += ps) {
                    if (points[j] == null)
                        continue;

                    for (m = 0; m < ps; ++m) {
                        val = points[j + m];
                        f = format[m];
                        if (!f)
                            continue;
                        
                        if (f.x) {
                            if (val < xmin)
                                xmin = val;
                            if (val > xmax)
                                xmax = val;
                        }
                        if (f.y) {
                            if (val < ymin)
                                ymin = val;
                            if (val > ymax)
                                ymax = val;
                        }
                    }
                }
                
                if (s.bars.show) {
                    // make sure we got room for the bar on the dancing floor
                    var delta = s.bars.align == "left" ? 0 : -s.bars.barWidth/2;
                    if (s.bars.horizontal) {
                        ymin += delta;
                        ymax += delta + s.bars.barWidth;
                    }
                    else {
                        xmin += delta;
                        xmax += delta + s.bars.barWidth;
                    }
                }
                
                updateAxis(s.xaxis, xmin, xmax);
                updateAxis(s.yaxis, ymin, ymax);
            }

            for (axis in axes) {
                if (axes[axis].datamin == topSentry)
                    axes[axis].datamin = null;
                if (axes[axis].datamax == bottomSentry)
                    axes[axis].datamax = null;
            }
        }

        function constructCanvas() {
            function makeCanvas(width, height) {
                var c = document.createElement('canvas');
                c.width = width;
                c.height = height;
                if (!c.getContext) // excanvas hack
                    c = window.G_vmlCanvasManager.initElement(c);
                return c;
            }
            
            canvasWidth = placeholder.width();
            canvasHeight = placeholder.height();
            placeholder.html(""); // clear placeholder
            if (placeholder.css("position") == 'static')
                placeholder.css("position", "relative"); // for positioning labels and overlay

            if (canvasWidth <= 0 || canvasHeight <= 0)
                throw "Invalid dimensions for plot, width = " + canvasWidth + ", height = " + canvasHeight;

            if (window.G_vmlCanvasManager) // excanvas hack
                window.G_vmlCanvasManager.init_(document); // make sure everything is setup
            
            // the canvas
            canvas = $(makeCanvas(canvasWidth, canvasHeight)).appendTo(placeholder).get(0);
            ctx = canvas.getContext("2d");

            // overlay canvas for interactive features
            overlay = $(makeCanvas(canvasWidth, canvasHeight)).css({ position: 'absolute', left: 0, top: 0 }).appendTo(placeholder).get(0);
            octx = overlay.getContext("2d");
            octx.stroke();
        }

        function bindEvents() {
            // we include the canvas in the event holder too, because IE 7
            // sometimes has trouble with the stacking order
            eventHolder = $([overlay, canvas]);

            // bind events
            if (options.grid.hoverable)
                eventHolder.mousemove(onMouseMove);

            if (options.grid.clickable)
                eventHolder.click(onClick);

            executeHooks(hooks.bindEvents, [eventHolder]);
        }

        function setupGrid() {
            function setTransformationHelpers(axis, o) {
                function identity(x) { return x; }
                
                var s, m, t = o.transform || identity,
                    it = o.inverseTransform;
                    
                // add transformation helpers
                if (axis == axes.xaxis || axis == axes.x2axis) {
                    // precompute how much the axis is scaling a point
                    // in canvas space
                    s = axis.scale = plotWidth / (t(axis.max) - t(axis.min));
                    m = t(axis.min);

                    // data point to canvas coordinate
                    if (t == identity) // slight optimization
                        axis.p2c = function (p) { return (p - m) * s; };
                    else
                        axis.p2c = function (p) { return (t(p) - m) * s; };
                    // canvas coordinate to data point
                    if (!it)
                        axis.c2p = function (c) { return m + c / s; };
                    else
                        axis.c2p = function (c) { return it(m + c / s); };
                }
                else {
                    s = axis.scale = plotHeight / (t(axis.max) - t(axis.min));
                    m = t(axis.max);
                    
                    if (t == identity)
                        axis.p2c = function (p) { return (m - p) * s; };
                    else
                        axis.p2c = function (p) { return (m - t(p)) * s; };
                    if (!it)
                        axis.c2p = function (c) { return m - c / s; };
                    else
                        axis.c2p = function (c) { return it(m - c / s); };
                }
            }

            function measureLabels(axis, axisOptions) {
                var i, labels = [], l;
                
                axis.labelWidth = axisOptions.labelWidth;
                axis.labelHeight = axisOptions.labelHeight;

                if (axis == axes.xaxis || axis == axes.x2axis) {
                    // to avoid measuring the widths of the labels, we
                    // construct fixed-size boxes and put the labels inside
                    // them, we don't need the exact figures and the
                    // fixed-size box content is easy to center
                    if (axis.labelWidth == null)
                        axis.labelWidth = canvasWidth / (axis.ticks.length > 0 ? axis.ticks.length : 1);

                    // measure x label heights
                    if (axis.labelHeight == null) {
                        labels = [];
                        for (i = 0; i < axis.ticks.length; ++i) {
                            l = axis.ticks[i].label;
                            if (l)
                                labels.push('<div class="tickLabel" style="float:left;width:' + axis.labelWidth + 'px">' + l + '</div>');
                        }
                        
                        if (labels.length > 0) {
                            var dummyDiv = $('<div style="position:absolute;top:-10000px;width:10000px;font-size:smaller">'
                                             + labels.join("") + '<div style="clear:left"></div></div>').appendTo(placeholder);
                            axis.labelHeight = dummyDiv.height();
                            dummyDiv.remove();
                        }
                    }
                }
                else if (axis.labelWidth == null || axis.labelHeight == null) {
                    // calculate y label dimensions
                    for (i = 0; i < axis.ticks.length; ++i) {
                        l = axis.ticks[i].label;
                        if (l)
                            labels.push('<div class="tickLabel">' + l + '</div>');
                    }
                    
                    if (labels.length > 0) {
                        var dummyDiv = $('<div style="position:absolute;top:-10000px;font-size:smaller">'
                                         + labels.join("") + '</div>').appendTo(placeholder);
                        if (axis.labelWidth == null)
                            axis.labelWidth = dummyDiv.width();
                        if (axis.labelHeight == null)
                            axis.labelHeight = dummyDiv.find("div").height();
                        dummyDiv.remove();
                    }
                    
                }

                if (axis.labelWidth == null)
                    axis.labelWidth = 0;
                if (axis.labelHeight == null)
                    axis.labelHeight = 0;
            }
            
            function setGridSpacing() {
                // get the most space needed around the grid for things
                // that may stick out
                var maxOutset = options.grid.borderWidth;
                for (i = 0; i < series.length; ++i)
                    maxOutset = Math.max(maxOutset, 2 * (series[i].points.radius + series[i].points.lineWidth/2));
                
                plotOffset.left = plotOffset.right = plotOffset.top = plotOffset.bottom = maxOutset;
                
                var margin = options.grid.labelMargin + options.grid.borderWidth;
                
                if (axes.xaxis.labelHeight > 0)
                    plotOffset.bottom = Math.max(maxOutset, axes.xaxis.labelHeight + margin);
                if (axes.yaxis.labelWidth > 0)
                    plotOffset.left = Math.max(maxOutset, axes.yaxis.labelWidth + margin);
                if (axes.x2axis.labelHeight > 0)
                    plotOffset.top = Math.max(maxOutset, axes.x2axis.labelHeight + margin);
                if (axes.y2axis.labelWidth > 0)
                    plotOffset.right = Math.max(maxOutset, axes.y2axis.labelWidth + margin);
            
                plotWidth = canvasWidth - plotOffset.left - plotOffset.right;
                plotHeight = canvasHeight - plotOffset.bottom - plotOffset.top;
            }
            
            var axis;
            for (axis in axes)
                setRange(axes[axis], options[axis]);
            
            if (options.grid.show) {
                for (axis in axes) {
                    prepareTickGeneration(axes[axis], options[axis]);
                    setTicks(axes[axis], options[axis]);
                    measureLabels(axes[axis], options[axis]);
                }

                setGridSpacing();
            }
            else {
                plotOffset.left = plotOffset.right = plotOffset.top = plotOffset.bottom = 0;
                plotWidth = canvasWidth;
                plotHeight = canvasHeight;
            }
            
            for (axis in axes)
                setTransformationHelpers(axes[axis], options[axis]);

            if (options.grid.show)
                insertLabels();
            
            insertLegend();
        }
        
        function setRange(axis, axisOptions) {
            var min = +(axisOptions.min != null ? axisOptions.min : axis.datamin),
                max = +(axisOptions.max != null ? axisOptions.max : axis.datamax),
                delta = max - min;

            if (delta == 0.0) {
                // degenerate case
                var widen = max == 0 ? 1 : 0.01;

                if (axisOptions.min == null)
                    min -= widen;
                // alway widen max if we couldn't widen min to ensure we
                // don't fall into min == max which doesn't work
                if (axisOptions.max == null || axisOptions.min != null)
                    max += widen;
            }
            else {
                // consider autoscaling
                var margin = axisOptions.autoscaleMargin;
                if (margin != null) {
                    if (axisOptions.min == null) {
                        min -= delta * margin;
                        // make sure we don't go below zero if all values
                        // are positive
                        if (min < 0 && axis.datamin != null && axis.datamin >= 0)
                            min = 0;
                    }
                    if (axisOptions.max == null) {
                        max += delta * margin;
                        if (max > 0 && axis.datamax != null && axis.datamax <= 0)
                            max = 0;
                    }
                }
            }
            axis.min = min;
            axis.max = max;
        }

        function prepareTickGeneration(axis, axisOptions) {
            // estimate number of ticks
            var noTicks;
            if (typeof axisOptions.ticks == "number" && axisOptions.ticks > 0)
                noTicks = axisOptions.ticks;
            else if (axis == axes.xaxis || axis == axes.x2axis)
                 // heuristic based on the model a*sqrt(x) fitted to
                 // some reasonable data points
                noTicks = 0.3 * Math.sqrt(canvasWidth);
            else
                noTicks = 0.3 * Math.sqrt(canvasHeight);
            
            var delta = (axis.max - axis.min) / noTicks,
                size, generator, unit, formatter, i, magn, norm;

            if (axisOptions.mode == "time") {
                // pretty handling of time
                
                // map of app. size of time units in milliseconds
                var timeUnitSize = {
                    "second": 1000,
                    "minute": 60 * 1000,
                    "hour": 60 * 60 * 1000,
                    "day": 24 * 60 * 60 * 1000,
                    "month": 30 * 24 * 60 * 60 * 1000,
                    "year": 365.2425 * 24 * 60 * 60 * 1000
                };


                // the allowed tick sizes, after 1 year we use
                // an integer algorithm
                var spec = [
                    [1, "second"], [2, "second"], [5, "second"], [10, "second"],
                    [30, "second"], 
                    [1, "minute"], [2, "minute"], [5, "minute"], [10, "minute"],
                    [30, "minute"], 
                    [1, "hour"], [2, "hour"], [4, "hour"],
                    [8, "hour"], [12, "hour"],
                    [1, "day"], [2, "day"], [3, "day"],
                    [0.25, "month"], [0.5, "month"], [1, "month"],
                    [2, "month"], [3, "month"], [6, "month"],
                    [1, "year"]
                ];

                var minSize = 0;
                if (axisOptions.minTickSize != null) {
                    if (typeof axisOptions.tickSize == "number")
                        minSize = axisOptions.tickSize;
                    else
                        minSize = axisOptions.minTickSize[0] * timeUnitSize[axisOptions.minTickSize[1]];
                }

                for (i = 0; i < spec.length - 1; ++i)
                    if (delta < (spec[i][0] * timeUnitSize[spec[i][1]]
                                 + spec[i + 1][0] * timeUnitSize[spec[i + 1][1]]) / 2
                       && spec[i][0] * timeUnitSize[spec[i][1]] >= minSize)
                        break;
                size = spec[i][0];
                unit = spec[i][1];
                
                // special-case the possibility of several years
                if (unit == "year") {
                    magn = Math.pow(10, Math.floor(Math.log(delta / timeUnitSize.year) / Math.LN10));
                    norm = (delta / timeUnitSize.year) / magn;
                    if (norm < 1.5)
                        size = 1;
                    else if (norm < 3)
                        size = 2;
                    else if (norm < 7.5)
                        size = 5;
                    else
                        size = 10;

                    size *= magn;
                }

                if (axisOptions.tickSize) {
                    size = axisOptions.tickSize[0];
                    unit = axisOptions.tickSize[1];
                }
                
                generator = function(axis) {
                    var ticks = [],
                        tickSize = axis.tickSize[0], unit = axis.tickSize[1],
                        d = new Date(axis.min);
                    
                    var step = tickSize * timeUnitSize[unit];

                    if (unit == "second")
                        d.setUTCSeconds(floorInBase(d.getUTCSeconds(), tickSize));
                    if (unit == "minute")
                        d.setUTCMinutes(floorInBase(d.getUTCMinutes(), tickSize));
                    if (unit == "hour")
                        d.setUTCHours(floorInBase(d.getUTCHours(), tickSize));
                    if (unit == "month")
                        d.setUTCMonth(floorInBase(d.getUTCMonth(), tickSize));
                    if (unit == "year")
                        d.setUTCFullYear(floorInBase(d.getUTCFullYear(), tickSize));
                    
                    // reset smaller components
                    d.setUTCMilliseconds(0);
                    if (step >= timeUnitSize.minute)
                        d.setUTCSeconds(0);
                    if (step >= timeUnitSize.hour)
                        d.setUTCMinutes(0);
                    if (step >= timeUnitSize.day)
                        d.setUTCHours(0);
                    if (step >= timeUnitSize.day * 4)
                        d.setUTCDate(1);
                    if (step >= timeUnitSize.year)
                        d.setUTCMonth(0);


                    var carry = 0, v = Number.NaN, prev;
                    do {
                        prev = v;
                        v = d.getTime();
                        ticks.push({ v: v, label: axis.tickFormatter(v, axis) });
                        if (unit == "month") {
                            if (tickSize < 1) {
                                // a bit complicated - we'll divide the month
                                // up but we need to take care of fractions
                                // so we don't end up in the middle of a day
                                d.setUTCDate(1);
                                var start = d.getTime();
                                d.setUTCMonth(d.getUTCMonth() + 1);
                                var end = d.getTime();
                                d.setTime(v + carry * timeUnitSize.hour + (end - start) * tickSize);
                                carry = d.getUTCHours();
                                d.setUTCHours(0);
                            }
                            else
                                d.setUTCMonth(d.getUTCMonth() + tickSize);
                        }
                        else if (unit == "year") {
                            d.setUTCFullYear(d.getUTCFullYear() + tickSize);
                        }
                        else
                            d.setTime(v + step);
                    } while (v < axis.max && v != prev);

                    return ticks;
                };

                formatter = function (v, axis) {
                    var d = new Date(v);

                    // first check global format
                    if (axisOptions.timeformat != null)
                        return $.plot.formatDate(d, axisOptions.timeformat, axisOptions.monthNames);
                    
                    var t = axis.tickSize[0] * timeUnitSize[axis.tickSize[1]];
                    var span = axis.max - axis.min;
                    var suffix = (axisOptions.twelveHourClock) ? " %p" : "";
                    
                    if (t < timeUnitSize.minute)
                        fmt = "%h:%M:%S" + suffix;
                    else if (t < timeUnitSize.day) {
                        if (span < 2 * timeUnitSize.day)
                            fmt = "%h:%M" + suffix;
                        else
                            fmt = "%b %d %h:%M" + suffix;
                    }
                    else if (t < timeUnitSize.month)
                        fmt = "%b %d";
                    else if (t < timeUnitSize.year) {
                        if (span < timeUnitSize.year)
                            fmt = "%b";
                        else
                            fmt = "%b %y";
                    }
                    else
                        fmt = "%y";
                    
                    return $.plot.formatDate(d, fmt, axisOptions.monthNames);
                };
            }
            else {
                // pretty rounding of base-10 numbers
                var maxDec = axisOptions.tickDecimals;
                var dec = -Math.floor(Math.log(delta) / Math.LN10);
                if (maxDec != null && dec > maxDec)
                    dec = maxDec;

                magn = Math.pow(10, -dec);
                norm = delta / magn; // norm is between 1.0 and 10.0
                
                if (norm < 1.5)
                    size = 1;
                else if (norm < 3) {
                    size = 2;
                    // special case for 2.5, requires an extra decimal
                    if (norm > 2.25 && (maxDec == null || dec + 1 <= maxDec)) {
                        size = 2.5;
                        ++dec;
                    }
                }
                else if (norm < 7.5)
                    size = 5;
                else
                    size = 10;

                size *= magn;
                
                if (axisOptions.minTickSize != null && size < axisOptions.minTickSize)
                    size = axisOptions.minTickSize;

                if (axisOptions.tickSize != null)
                    size = axisOptions.tickSize;

                axis.tickDecimals = Math.max(0, (maxDec != null) ? maxDec : dec);

                generator = function (axis) {
                    var ticks = [];

                    // spew out all possible ticks
                    var start = floorInBase(axis.min, axis.tickSize),
                        i = 0, v = Number.NaN, prev;
                    do {
                        prev = v;
                        v = start + i * axis.tickSize;
                        ticks.push({ v: v, label: axis.tickFormatter(v, axis) });
                        ++i;
                    } while (v < axis.max && v != prev);
                    return ticks;
                };

                formatter = function (v, axis) {
                    return v.toFixed(axis.tickDecimals);
                };
            }

            axis.tickSize = unit ? [size, unit] : size;
            axis.tickGenerator = generator;
            if ($.isFunction(axisOptions.tickFormatter))
                axis.tickFormatter = function (v, axis) { return "" + axisOptions.tickFormatter(v, axis); };
            else
                axis.tickFormatter = formatter;
        }
        
        function setTicks(axis, axisOptions) {
            axis.ticks = [];

            if (!axis.used)
                return;
            
            if (axisOptions.ticks == null)
                axis.ticks = axis.tickGenerator(axis);
            else if (typeof axisOptions.ticks == "number") {
                if (axisOptions.ticks > 0)
                    axis.ticks = axis.tickGenerator(axis);
            }
            else if (axisOptions.ticks) {
                var ticks = axisOptions.ticks;

                if ($.isFunction(ticks))
                    // generate the ticks
                    ticks = ticks({ min: axis.min, max: axis.max });
                
                // clean up the user-supplied ticks, copy them over
                var i, v;
                for (i = 0; i < ticks.length; ++i) {
                    var label = null;
                    var t = ticks[i];
                    if (typeof t == "object") {
                        v = t[0];
                        if (t.length > 1)
                            label = t[1];
                    }
                    else
                        v = t;
                    if (label == null)
                        label = axis.tickFormatter(v, axis);
                    axis.ticks[i] = { v: v, label: label };
                }
            }

            if (axisOptions.autoscaleMargin != null && axis.ticks.length > 0) {
                // snap to ticks
                if (axisOptions.min == null)
                    axis.min = Math.min(axis.min, axis.ticks[0].v);
                if (axisOptions.max == null && axis.ticks.length > 1)
                    axis.max = Math.max(axis.max, axis.ticks[axis.ticks.length - 1].v);
            }
        }
      
        function draw() {
            ctx.clearRect(0, 0, canvasWidth, canvasHeight);

            var grid = options.grid;
            
            if (grid.show && !grid.aboveData)
                drawGrid();

            for (var i = 0; i < series.length; ++i)
                drawSeries(series[i]);

            executeHooks(hooks.draw, [ctx]);
            
            if (grid.show && grid.aboveData)
                drawGrid();
        }

        function extractRange(ranges, coord) {
            var firstAxis = coord + "axis",
                secondaryAxis = coord + "2axis",
                axis, from, to, reverse;

            if (ranges[firstAxis]) {
                axis = axes[firstAxis];
                from = ranges[firstAxis].from;
                to = ranges[firstAxis].to;
            }
            else if (ranges[secondaryAxis]) {
                axis = axes[secondaryAxis];
                from = ranges[secondaryAxis].from;
                to = ranges[secondaryAxis].to;
            }
            else {
                // backwards-compat stuff - to be removed in future
                axis = axes[firstAxis];
                from = ranges[coord + "1"];
                to = ranges[coord + "2"];
            }

            // auto-reverse as an added bonus
            if (from != null && to != null && from > to)
                return { from: to, to: from, axis: axis };
            
            return { from: from, to: to, axis: axis };
        }
        
        function drawGrid() {
            var i;
            
            ctx.save();
            ctx.translate(plotOffset.left, plotOffset.top);

            // draw background, if any
            if (options.grid.backgroundColor) {
                ctx.fillStyle = getColorOrGradient(options.grid.backgroundColor, plotHeight, 0, "rgba(255, 255, 255, 0)");
                ctx.fillRect(0, 0, plotWidth, plotHeight);
            }

            // draw markings
            var markings = options.grid.markings;
            if (markings) {
                if ($.isFunction(markings))
                    // xmin etc. are backwards-compatible, to be removed in future
                    markings = markings({ xmin: axes.xaxis.min, xmax: axes.xaxis.max, ymin: axes.yaxis.min, ymax: axes.yaxis.max, xaxis: axes.xaxis, yaxis: axes.yaxis, x2axis: axes.x2axis, y2axis: axes.y2axis });

                for (i = 0; i < markings.length; ++i) {
                    var m = markings[i],
                        xrange = extractRange(m, "x"),
                        yrange = extractRange(m, "y");

                    // fill in missing
                    if (xrange.from == null)
                        xrange.from = xrange.axis.min;
                    if (xrange.to == null)
                        xrange.to = xrange.axis.max;
                    if (yrange.from == null)
                        yrange.from = yrange.axis.min;
                    if (yrange.to == null)
                        yrange.to = yrange.axis.max;

                    // clip
                    if (xrange.to < xrange.axis.min || xrange.from > xrange.axis.max ||
                        yrange.to < yrange.axis.min || yrange.from > yrange.axis.max)
                        continue;

                    xrange.from = Math.max(xrange.from, xrange.axis.min);
                    xrange.to = Math.min(xrange.to, xrange.axis.max);
                    yrange.from = Math.max(yrange.from, yrange.axis.min);
                    yrange.to = Math.min(yrange.to, yrange.axis.max);

                    if (xrange.from == xrange.to && yrange.from == yrange.to)
                        continue;

                    // then draw
                    xrange.from = xrange.axis.p2c(xrange.from);
                    xrange.to = xrange.axis.p2c(xrange.to);
                    yrange.from = yrange.axis.p2c(yrange.from);
                    yrange.to = yrange.axis.p2c(yrange.to);
                    
                    if (xrange.from == xrange.to || yrange.from == yrange.to) {
                        // draw line
                        ctx.beginPath();
                        ctx.strokeStyle = m.color || options.grid.markingsColor;
                        ctx.lineWidth = m.lineWidth || options.grid.markingsLineWidth;
                        //ctx.moveTo(Math.floor(xrange.from), yrange.from);
                        //ctx.lineTo(Math.floor(xrange.to), yrange.to);
                        ctx.moveTo(xrange.from, yrange.from);
                        ctx.lineTo(xrange.to, yrange.to);
                        ctx.stroke();
                    }
                    else {
                        // fill area
                        ctx.fillStyle = m.color || options.grid.markingsColor;
                        ctx.fillRect(xrange.from, yrange.to,
                                     xrange.to - xrange.from,
                                     yrange.from - yrange.to);
                    }
                }
            }
            
            // draw the inner grid
            ctx.lineWidth = 1;
            ctx.strokeStyle = options.grid.tickColor;
            ctx.beginPath();
            var v, axis = axes.xaxis,
                bw = options.grid.borderWidth;
            for (i = 0; i < axis.ticks.length; ++i) {
                v = axis.ticks[i].v;
                if (v < axis.min || v > axis.max ||
                    (bw > 0 && (v == axis.min || v == axis.max)))
                    continue;   // skip those lying on the axes if we got a border

                ctx.moveTo(Math.floor(axis.p2c(v)) + ctx.lineWidth/2, 0);
                ctx.lineTo(Math.floor(axis.p2c(v)) + ctx.lineWidth/2, plotHeight);
            }

            axis = axes.yaxis;
            for (i = 0; i < axis.ticks.length; ++i) {
                v = axis.ticks[i].v;
                if (v < axis.min || v > axis.max ||
                    (bw > 0 && (v == axis.min || v == axis.max)))
                    continue;

                ctx.moveTo(0, Math.floor(axis.p2c(v)) + ctx.lineWidth/2);
                ctx.lineTo(plotWidth, Math.floor(axis.p2c(v)) + ctx.lineWidth/2);
            }

            axis = axes.x2axis;
            for (i = 0; i < axis.ticks.length; ++i) {
                v = axis.ticks[i].v;
                if (v < axis.min || v > axis.max ||
                    (bw > 0 && (v == axis.min || v == axis.max)))
                    continue;
    
                ctx.moveTo(Math.floor(axis.p2c(v)) + ctx.lineWidth/2, -5);
                ctx.lineTo(Math.floor(axis.p2c(v)) + ctx.lineWidth/2, 5);
            }

            axis = axes.y2axis;
            for (i = 0; i < axis.ticks.length; ++i) {
                v = axis.ticks[i].v;
                if (v < axis.min || v > axis.max ||
                    (bw > 0 && (v == axis.min || v == axis.max)))
                    continue;

                ctx.moveTo(plotWidth-5, Math.floor(axis.p2c(v)) + ctx.lineWidth/2);
                ctx.lineTo(plotWidth+5, Math.floor(axis.p2c(v)) + ctx.lineWidth/2);
            }
            
            ctx.stroke();
            
            if (options.grid.borderWidth) {
                // draw border
                ctx.lineWidth = bw;
                ctx.strokeStyle = options.grid.borderColor;
                ctx.strokeRect(-bw/2, -bw/2, plotWidth + bw, plotHeight + bw);
            }

            ctx.restore();
        }

        function insertLabels() {
            placeholder.find(".tickLabels").remove();
            
            var html = ['<div class="tickLabels" style="font-size:smaller;color:' + options.grid.color + '">'];

            function addLabels(axis, labelGenerator) {
                for (var i = 0; i < axis.ticks.length; ++i) {
                    var tick = axis.ticks[i];
                    if (!tick.label || tick.v < axis.min || tick.v > axis.max)
                        continue;
                    html.push(labelGenerator(tick, axis));
                }
            }

            var margin = options.grid.labelMargin + options.grid.borderWidth;
            
            addLabels(axes.xaxis, function (tick, axis) {
                return '<div style="position:absolute;top:' + (plotOffset.top + plotHeight + margin) + 'px;left:' + Math.round(plotOffset.left + axis.p2c(tick.v) - axis.labelWidth/2) + 'px;width:' + axis.labelWidth + 'px;text-align:center" class="tickLabel">' + tick.label + "</div>";
            });
            
            
            addLabels(axes.yaxis, function (tick, axis) {
                return '<div style="position:absolute;top:' + Math.round(plotOffset.top + axis.p2c(tick.v) - axis.labelHeight/2) + 'px;right:' + (plotOffset.right + plotWidth + margin) + 'px;width:' + axis.labelWidth + 'px;text-align:right" class="tickLabel">' + tick.label + "</div>";
            });
            
            addLabels(axes.x2axis, function (tick, axis) {
                return '<div style="position:absolute;bottom:' + (plotOffset.bottom + plotHeight + margin) + 'px;left:' + Math.round(plotOffset.left + axis.p2c(tick.v) - axis.labelWidth/2) + 'px;width:' + axis.labelWidth + 'px;text-align:center" class="tickLabel">' + tick.label + "</div>";
            });
            
            addLabels(axes.y2axis, function (tick, axis) {
                return '<div style="position:absolute;top:' + Math.round(plotOffset.top + axis.p2c(tick.v) - axis.labelHeight/2) + 'px;left:' + (plotOffset.left + plotWidth + margin) +'px;width:' + axis.labelWidth + 'px;text-align:left" class="tickLabel">' + tick.label + "</div>";
            });

            html.push('</div>');
            
            placeholder.append(html.join(""));
        }

        function drawSeries(series) {
            if (series.lines.show)
                drawSeriesLines(series);
            if (series.bars.show)
                drawSeriesBars(series);
            if (series.points.show)
                drawSeriesPoints(series);
        }
        
        function drawSeriesLines(series) {
            function plotLine(datapoints, xoffset, yoffset, axisx, axisy) {
                var points = datapoints.points,
                    ps = datapoints.pointsize,
                    prevx = null, prevy = null;
                
                ctx.beginPath();
                for (var i = ps; i < points.length; i += ps) {
                    var x1 = points[i - ps], y1 = points[i - ps + 1],
                        x2 = points[i], y2 = points[i + 1];
                    
                    if (x1 == null || x2 == null)
                        continue;

                    // clip with ymin
                    if (y1 <= y2 && y1 < axisy.min) {
                        if (y2 < axisy.min)
                            continue;   // line segment is outside
                        // compute new intersection point
                        x1 = (axisy.min - y1) / (y2 - y1) * (x2 - x1) + x1;
                        y1 = axisy.min;
                    }
                    else if (y2 <= y1 && y2 < axisy.min) {
                        if (y1 < axisy.min)
                            continue;
                        x2 = (axisy.min - y1) / (y2 - y1) * (x2 - x1) + x1;
                        y2 = axisy.min;
                    }

                    // clip with ymax
                    if (y1 >= y2 && y1 > axisy.max) {
                        if (y2 > axisy.max)
                            continue;
                        x1 = (axisy.max - y1) / (y2 - y1) * (x2 - x1) + x1;
                        y1 = axisy.max;
                    }
                    else if (y2 >= y1 && y2 > axisy.max) {
                        if (y1 > axisy.max)
                            continue;
                        x2 = (axisy.max - y1) / (y2 - y1) * (x2 - x1) + x1;
                        y2 = axisy.max;
                    }

                    // clip with xmin
                    if (x1 <= x2 && x1 < axisx.min) {
                        if (x2 < axisx.min)
                            continue;
                        y1 = (axisx.min - x1) / (x2 - x1) * (y2 - y1) + y1;
                        x1 = axisx.min;
                    }
                    else if (x2 <= x1 && x2 < axisx.min) {
                        if (x1 < axisx.min)
                            continue;
                        y2 = (axisx.min - x1) / (x2 - x1) * (y2 - y1) + y1;
                        x2 = axisx.min;
                    }

                    // clip with xmax
                    if (x1 >= x2 && x1 > axisx.max) {
                        if (x2 > axisx.max)
                            continue;
                        y1 = (axisx.max - x1) / (x2 - x1) * (y2 - y1) + y1;
                        x1 = axisx.max;
                    }
                    else if (x2 >= x1 && x2 > axisx.max) {
                        if (x1 > axisx.max)
                            continue;
                        y2 = (axisx.max - x1) / (x2 - x1) * (y2 - y1) + y1;
                        x2 = axisx.max;
                    }

                    if (x1 != prevx || y1 != prevy)
                        ctx.moveTo(axisx.p2c(x1) + xoffset, axisy.p2c(y1) + yoffset);
                    
                    prevx = x2;
                    prevy = y2;
                    ctx.lineTo(axisx.p2c(x2) + xoffset, axisy.p2c(y2) + yoffset);
                }
                ctx.stroke();
            }

            function plotLineArea(datapoints, axisx, axisy) {
                var points = datapoints.points,
                    ps = datapoints.pointsize,
                    bottom = Math.min(Math.max(0, axisy.min), axisy.max),
                    i = 0, top, areaOpen = false,
                    ypos = 1, segmentStart = 0, segmentEnd = 0;

                // we process each segment in two turns, first forward
                // direction to sketch out top, then once we hit the
                // end we go backwards to sketch the bottom
                while (true) {
                    if (ps > 0 && i > points.length + ps)
                        break;

                    i += ps; // ps is negative if going backwards

                    var x1 = points[i - ps],
                        y1 = points[i - ps + ypos],
                        x2 = points[i], y2 = points[i + ypos];

                    if (areaOpen) {
                        if (ps > 0 && x1 != null && x2 == null) {
                            // at turning point
                            segmentEnd = i;
                            ps = -ps;
                            ypos = 2;
                            continue;
                        }

                        if (ps < 0 && i == segmentStart + ps) {
                            // done with the reverse sweep
                            ctx.fill();
                            areaOpen = false;
                            ps = -ps;
                            ypos = 1;
                            i = segmentStart = segmentEnd + ps;
                            continue;
                        }
                    }

                    if (x1 == null || x2 == null)
                        continue;

                    // clip x values
                    
                    // clip with xmin
                    if (x1 <= x2 && x1 < axisx.min) {
                        if (x2 < axisx.min)
                            continue;
                        y1 = (axisx.min - x1) / (x2 - x1) * (y2 - y1) + y1;
                        x1 = axisx.min;
                    }
                    else if (x2 <= x1 && x2 < axisx.min) {
                        if (x1 < axisx.min)
                            continue;
                        y2 = (axisx.min - x1) / (x2 - x1) * (y2 - y1) + y1;
                        x2 = axisx.min;
                    }

                    // clip with xmax
                    if (x1 >= x2 && x1 > axisx.max) {
                        if (x2 > axisx.max)
                            continue;
                        y1 = (axisx.max - x1) / (x2 - x1) * (y2 - y1) + y1;
                        x1 = axisx.max;
                    }
                    else if (x2 >= x1 && x2 > axisx.max) {
                        if (x1 > axisx.max)
                            continue;
                        y2 = (axisx.max - x1) / (x2 - x1) * (y2 - y1) + y1;
                        x2 = axisx.max;
                    }

                    if (!areaOpen) {
                        // open area
                        ctx.beginPath();
                        ctx.moveTo(axisx.p2c(x1), axisy.p2c(bottom));
                        areaOpen = true;
                    }
                    
                    // now first check the case where both is outside
                    if (y1 >= axisy.max && y2 >= axisy.max) {
                        ctx.lineTo(axisx.p2c(x1), axisy.p2c(axisy.max));
                        ctx.lineTo(axisx.p2c(x2), axisy.p2c(axisy.max));
                        continue;
                    }
                    else if (y1 <= axisy.min && y2 <= axisy.min) {
                        ctx.lineTo(axisx.p2c(x1), axisy.p2c(axisy.min));
                        ctx.lineTo(axisx.p2c(x2), axisy.p2c(axisy.min));
                        continue;
                    }
                    
                    // else it's a bit more complicated, there might
                    // be a flat maxed out rectangle first, then a
                    // triangular cutout or reverse; to find these
                    // keep track of the current x values
                    var x1old = x1, x2old = x2;

                    // clip the y values, without shortcutting, we
                    // go through all cases in turn
                    
                    // clip with ymin
                    if (y1 <= y2 && y1 < axisy.min && y2 >= axisy.min) {
                        x1 = (axisy.min - y1) / (y2 - y1) * (x2 - x1) + x1;
                        y1 = axisy.min;
                    }
                    else if (y2 <= y1 && y2 < axisy.min && y1 >= axisy.min) {
                        x2 = (axisy.min - y1) / (y2 - y1) * (x2 - x1) + x1;
                        y2 = axisy.min;
                    }

                    // clip with ymax
                    if (y1 >= y2 && y1 > axisy.max && y2 <= axisy.max) {
                        x1 = (axisy.max - y1) / (y2 - y1) * (x2 - x1) + x1;
                        y1 = axisy.max;
                    }
                    else if (y2 >= y1 && y2 > axisy.max && y1 <= axisy.max) {
                        x2 = (axisy.max - y1) / (y2 - y1) * (x2 - x1) + x1;
                        y2 = axisy.max;
                    }

                    // if the x value was changed we got a rectangle
                    // to fill
                    if (x1 != x1old) {
                        ctx.lineTo(axisx.p2c(x1old), axisy.p2c(y1));
                        // it goes to (x1, y1), but we fill that below
                    }
                    
                    // fill triangular section, this sometimes result
                    // in redundant points if (x1, y1) hasn't changed
                    // from previous line to, but we just ignore that
                    ctx.lineTo(axisx.p2c(x1), axisy.p2c(y1));
                    ctx.lineTo(axisx.p2c(x2), axisy.p2c(y2));

                    // fill the other rectangle if it's there
                    if (x2 != x2old) {
                        ctx.lineTo(axisx.p2c(x2), axisy.p2c(y2));
                        ctx.lineTo(axisx.p2c(x2old), axisy.p2c(y2));
                    }
                }
            }

            ctx.save();
            ctx.translate(plotOffset.left, plotOffset.top);
            ctx.lineJoin = "round";

            var lw = series.lines.lineWidth,
                sw = series.shadowSize;
            // FIXME: consider another form of shadow when filling is turned on
            if (lw > 0 && sw > 0) {
                // draw shadow as a thick and thin line with transparency
                ctx.lineWidth = sw;
                ctx.strokeStyle = "rgba(0,0,0,0.1)";
                // position shadow at angle from the mid of line
                var angle = Math.PI/18;
                plotLine(series.datapoints, Math.sin(angle) * (lw/2 + sw/2), Math.cos(angle) * (lw/2 + sw/2), series.xaxis, series.yaxis);
                ctx.lineWidth = sw/2;
                plotLine(series.datapoints, Math.sin(angle) * (lw/2 + sw/4), Math.cos(angle) * (lw/2 + sw/4), series.xaxis, series.yaxis);
            }

            ctx.lineWidth = lw;
            ctx.strokeStyle = series.color;
            var fillStyle = getFillStyle(series.lines, series.color, 0, plotHeight);
            if (fillStyle) {
                ctx.fillStyle = fillStyle;
                plotLineArea(series.datapoints, series.xaxis, series.yaxis);
            }

            if (lw > 0)
                plotLine(series.datapoints, 0, 0, series.xaxis, series.yaxis);
            ctx.restore();
        }

        function drawSeriesPoints(series) {
            function plotPoints(datapoints, radius, fillStyle, offset, circumference, axisx, axisy) {
                var points = datapoints.points, ps = datapoints.pointsize;
                
                for (var i = 0; i < points.length; i += ps) {
                    var x = points[i], y = points[i + 1];
                    if (x == null || x < axisx.min || x > axisx.max || y < axisy.min || y > axisy.max)
                        continue;
                    
                    ctx.beginPath();
                    ctx.arc(axisx.p2c(x), axisy.p2c(y) + offset, radius, 0, circumference, false);
                    if (fillStyle) {
                        ctx.fillStyle = fillStyle;
                        ctx.fill();
                    }
                    ctx.stroke();
                }
            }
            
            ctx.save();
            ctx.translate(plotOffset.left, plotOffset.top);

            var lw = series.lines.lineWidth,
                sw = series.shadowSize,
                radius = series.points.radius;
            if (lw > 0 && sw > 0) {
                // draw shadow in two steps
                var w = sw / 2;
                ctx.lineWidth = w;
                ctx.strokeStyle = "rgba(0,0,0,0.1)";
                plotPoints(series.datapoints, radius, null, w + w/2, Math.PI,
                           series.xaxis, series.yaxis);

                ctx.strokeStyle = "rgba(0,0,0,0.2)";
                plotPoints(series.datapoints, radius, null, w/2, Math.PI,
                           series.xaxis, series.yaxis);
            }

            ctx.lineWidth = lw;
            ctx.strokeStyle = series.color;
            plotPoints(series.datapoints, radius,
                       getFillStyle(series.points, series.color), 0, 2 * Math.PI,
                       series.xaxis, series.yaxis);
            ctx.restore();
        }

        function drawBar(x, y, b, barLeft, barRight, offset, fillStyleCallback, axisx, axisy, c, horizontal) {
            var left, right, bottom, top,
                drawLeft, drawRight, drawTop, drawBottom,
                tmp;

            // in horizontal mode, we start the bar from the left
            // instead of from the bottom so it appears to be
            // horizontal rather than vertical
            if (horizontal) {
                drawBottom = drawRight = drawTop = true;
                drawLeft = false;
                left = b;
                right = x;
                top = y + barLeft;
                bottom = y + barRight;

                // account for negative bars
                if (right < left) {
                    tmp = right;
                    right = left;
                    left = tmp;
                    drawLeft = true;
                    drawRight = false;
                }
            }
            else {
                drawLeft = drawRight = drawTop = true;
                drawBottom = false;
                left = x + barLeft;
                right = x + barRight;
                bottom = b;
                top = y;

                // account for negative bars
                if (top < bottom) {
                    tmp = top;
                    top = bottom;
                    bottom = tmp;
                    drawBottom = true;
                    drawTop = false;
                }
            }
           
            // clip
            if (right < axisx.min || left > axisx.max ||
                top < axisy.min || bottom > axisy.max)
                return;
            
            if (left < axisx.min) {
                left = axisx.min;
                drawLeft = false;
            }

            if (right > axisx.max) {
                right = axisx.max;
                drawRight = false;
            }

            if (bottom < axisy.min) {
                bottom = axisy.min;
                drawBottom = false;
            }
            
            if (top > axisy.max) {
                top = axisy.max;
                drawTop = false;
            }

            left = axisx.p2c(left);
            bottom = axisy.p2c(bottom);
            right = axisx.p2c(right);
            top = axisy.p2c(top);
            
            // fill the bar
            if (fillStyleCallback) {
                c.beginPath();
                c.moveTo(left, bottom);
                c.lineTo(left, top);
                c.lineTo(right, top);
                c.lineTo(right, bottom);
                c.fillStyle = fillStyleCallback(bottom, top);
                c.fill();
            }

            // draw outline
            if (drawLeft || drawRight || drawTop || drawBottom) {
                c.beginPath();

                // FIXME: inline moveTo is buggy with excanvas
                c.moveTo(left, bottom + offset);
                if (drawLeft)
                    c.lineTo(left, top + offset);
                else
                    c.moveTo(left, top + offset);
                if (drawTop)
                    c.lineTo(right, top + offset);
                else
                    c.moveTo(right, top + offset);
                if (drawRight)
                    c.lineTo(right, bottom + offset);
                else
                    c.moveTo(right, bottom + offset);
                if (drawBottom)
                    c.lineTo(left, bottom + offset);
                else
                    c.moveTo(left, bottom + offset);
                c.stroke();
            }
        }
        
        function drawSeriesBars(series) {
            function plotBars(datapoints, barLeft, barRight, offset, fillStyleCallback, axisx, axisy) {
                var points = datapoints.points, ps = datapoints.pointsize;
                
                for (var i = 0; i < points.length; i += ps) {
                    if (points[i] == null)
                        continue;
                    drawBar(points[i], points[i + 1], points[i + 2], barLeft, barRight, offset, fillStyleCallback, axisx, axisy, ctx, series.bars.horizontal);
                }
            }

            ctx.save();
            ctx.translate(plotOffset.left, plotOffset.top);

            // FIXME: figure out a way to add shadows (for instance along the right edge)
            ctx.lineWidth = series.bars.lineWidth;
            ctx.strokeStyle = series.color;
            var barLeft = series.bars.align == "left" ? 0 : -series.bars.barWidth/2;
            var fillStyleCallback = series.bars.fill ? function (bottom, top) { return getFillStyle(series.bars, series.color, bottom, top); } : null;
            plotBars(series.datapoints, barLeft, barLeft + series.bars.barWidth, 0, fillStyleCallback, series.xaxis, series.yaxis);
            ctx.restore();
        }

        function getFillStyle(filloptions, seriesColor, bottom, top) {
            var fill = filloptions.fill;
            if (!fill)
                return null;

            if (filloptions.fillColor)
                return getColorOrGradient(filloptions.fillColor, bottom, top, seriesColor);
            
            var c = $.color.parse(seriesColor);
            c.a = typeof fill == "number" ? fill : 0.4;
            c.normalize();
            return c.toString();
        }
        
        function insertLegend() {
            placeholder.find(".legend").remove();

            if (!options.legend.show)
                return;
            
            var fragments = [], rowStarted = false,
                lf = options.legend.labelFormatter, s, label;
            for (i = 0; i < series.length; ++i) {
                s = series[i];
                label = s.label;
                if (!label)
                    continue;
                
                if (i % options.legend.noColumns == 0) {
                    if (rowStarted)
                        fragments.push('</tr>');
                    fragments.push('<tr>');
                    rowStarted = true;
                }

                if (lf)
                    label = lf(label, s);
                
                fragments.push(
                    '<td class="legendColorBox"><div style="border:1px solid ' + options.legend.labelBoxBorderColor + ';padding:1px"><div style="width:4px;height:0;border:5px solid ' + s.color + ';overflow:hidden"></div></div></td>' +
                    '<td class="legendLabel">' + label + '</td>');
            }
            if (rowStarted)
                fragments.push('</tr>');
            
            if (fragments.length == 0)
                return;

            var table = '<table style="font-size:smaller;color:' + options.grid.color + '">' + fragments.join("") + '</table>';
            if (options.legend.container != null)
                $(options.legend.container).html(table);
            else {
                var pos = "",
                    p = options.legend.position,
                    m = options.legend.margin;
                if (m[0] == null)
                    m = [m, m];
                if (p.charAt(0) == "n")
                    pos += 'top:' + (m[1] + plotOffset.top) + 'px;';
                else if (p.charAt(0) == "s")
                    pos += 'bottom:' + (m[1] + plotOffset.bottom) + 'px;';
                if (p.charAt(1) == "e")
                    pos += 'right:' + (m[0] + plotOffset.right) + 'px;';
                else if (p.charAt(1) == "w")
                    pos += 'left:' + (m[0] + plotOffset.left) + 'px;';
                var legend = $('<div class="legend">' + table.replace('style="', 'style="position:absolute;' + pos +';') + '</div>').appendTo(placeholder);
                if (options.legend.backgroundOpacity != 0.0) {
                    // put in the transparent background
                    // separately to avoid blended labels and
                    // label boxes
                    var c = options.legend.backgroundColor;
                    if (c == null) {
                        c = options.grid.backgroundColor;
                        if (c && typeof c == "string")
                            c = $.color.parse(c);
                        else
                            c = $.color.extract(legend, 'background-color');
                        c.a = 1;
                        c = c.toString();
                    }
                    var div = legend.children();
                    $('<div style="position:absolute;width:' + div.width() + 'px;height:' + div.height() + 'px;' + pos +'background-color:' + c + ';"> </div>').prependTo(legend).css('opacity', options.legend.backgroundOpacity);
                }
            }
        }


        // interactive features
        
        var highlights = [],
            redrawTimeout = null;
        
        // returns the data item the mouse is over, or null if none is found
        function findNearbyItem(mouseX, mouseY, seriesFilter) {
            var maxDistance = options.grid.mouseActiveRadius,
                smallestDistance = maxDistance * maxDistance + 1,
                item = null, foundPoint = false, i, j;

            for (i = series.length - 1; i >= 0; --i) {
                if (!seriesFilter(series[i]))
                    continue;
                
                var s = series[i],
                    axisx = s.xaxis,
                    axisy = s.yaxis,
                    points = s.datapoints.points,
                    ps = s.datapoints.pointsize,
                    mx = axisx.c2p(mouseX), // precompute some stuff to make the loop faster
                    my = axisy.c2p(mouseY),
                    maxx = maxDistance / axisx.scale,
                    maxy = maxDistance / axisy.scale;

                if (s.lines.show || s.points.show) {
                    for (j = 0; j < points.length; j += ps) {
                        var x = points[j], y = points[j + 1];
                        if (x == null)
                            continue;
                        
                        // For points and lines, the cursor must be within a
                        // certain distance to the data point
                        if (x - mx > maxx || x - mx < -maxx ||
                            y - my > maxy || y - my < -maxy)
                            continue;

                        // We have to calculate distances in pixels, not in
                        // data units, because the scales of the axes may be different
                        var dx = Math.abs(axisx.p2c(x) - mouseX),
                            dy = Math.abs(axisy.p2c(y) - mouseY),
                            dist = dx * dx + dy * dy; // we save the sqrt

                        // use <= to ensure last point takes precedence
                        // (last generally means on top of)
                        if (dist < smallestDistance) {
                            smallestDistance = dist;
                            item = [i, j / ps];
                        }
                    }
                }
                    
                if (s.bars.show && !item) { // no other point can be nearby
                    var barLeft = s.bars.align == "left" ? 0 : -s.bars.barWidth/2,
                        barRight = barLeft + s.bars.barWidth;
                    
                    for (j = 0; j < points.length; j += ps) {
                        var x = points[j], y = points[j + 1], b = points[j + 2];
                        if (x == null)
                            continue;
  
                        // for a bar graph, the cursor must be inside the bar
                        if (series[i].bars.horizontal ? 
                            (mx <= Math.max(b, x) && mx >= Math.min(b, x) && 
                             my >= y + barLeft && my <= y + barRight) :
                            (mx >= x + barLeft && mx <= x + barRight &&
                             my >= Math.min(b, y) && my <= Math.max(b, y)))
                                item = [i, j / ps];
                    }
                }
            }

            if (item) {
                i = item[0];
                j = item[1];
                ps = series[i].datapoints.pointsize;
                
                return { datapoint: series[i].datapoints.points.slice(j * ps, (j + 1) * ps),
                         dataIndex: j,
                         series: series[i],
                         seriesIndex: i };
            }
            
            return null;
        }

        function onMouseMove(e) {
            if (options.grid.hoverable)
                triggerClickHoverEvent("plothover", e,
                                       function (s) { return s["hoverable"] != false; });
        }
        
        function onClick(e) {
            triggerClickHoverEvent("plotclick", e,
                                   function (s) { return s["clickable"] != false; });
        }

        // trigger click or hover event (they send the same parameters
        // so we share their code)
        function triggerClickHoverEvent(eventname, event, seriesFilter) {
            var offset = eventHolder.offset(),
                pos = { pageX: event.pageX, pageY: event.pageY },
                canvasX = event.pageX - offset.left - plotOffset.left,
                canvasY = event.pageY - offset.top - plotOffset.top;

            if (axes.xaxis.used)
                pos.x = axes.xaxis.c2p(canvasX);
            if (axes.yaxis.used)
                pos.y = axes.yaxis.c2p(canvasY);
            if (axes.x2axis.used)
                pos.x2 = axes.x2axis.c2p(canvasX);
            if (axes.y2axis.used)
                pos.y2 = axes.y2axis.c2p(canvasY);

            var item = findNearbyItem(canvasX, canvasY, seriesFilter);

            if (item) {
                // fill in mouse pos for any listeners out there
                item.pageX = parseInt(item.series.xaxis.p2c(item.datapoint[0]) + offset.left + plotOffset.left);
                item.pageY = parseInt(item.series.yaxis.p2c(item.datapoint[1]) + offset.top + plotOffset.top);
            }

            if (options.grid.autoHighlight) {
                // clear auto-highlights
                for (var i = 0; i < highlights.length; ++i) {
                    var h = highlights[i];
                    if (h.auto == eventname &&
                        !(item && h.series == item.series && h.point == item.datapoint))
                        unhighlight(h.series, h.point);
                }
                
                if (item)
                    highlight(item.series, item.datapoint, eventname);
            }
            
            placeholder.trigger(eventname, [ pos, item ]);
        }

        function triggerRedrawOverlay() {
            if (!redrawTimeout)
                redrawTimeout = setTimeout(drawOverlay, 30);
        }

        function drawOverlay() {
            redrawTimeout = null;
            
            // draw highlights
            octx.save();
            octx.clearRect(0, 0, canvasWidth, canvasHeight);
            octx.translate(plotOffset.left, plotOffset.top);
            var i, hi;
            for (i = 0; i < highlights.length; ++i) {
                hi = highlights[i];

                if (hi.series.bars.show)
                    drawBarHighlight(hi.series, hi.point);
                else
                    drawPointHighlight(hi.series, hi.point);
            }
            octx.restore();
            
            executeHooks(hooks.drawOverlay, [octx]);
        }
        
        function highlight(s, point, auto) {
            if (typeof s == "number")
                s = series[s];

            if (typeof point == "number")
                point = s.data[point];

            var i = indexOfHighlight(s, point);
            if (i == -1) {
                highlights.push({ series: s, point: point, auto: auto });

                triggerRedrawOverlay();
            }
            else if (!auto)
                highlights[i].auto = false;
        }
            
        function unhighlight(s, point) {
            if (s == null && point == null) {
                highlights = [];
                triggerRedrawOverlay();
            }
            
            if (typeof s == "number")
                s = series[s];

            if (typeof point == "number")
                point = s.data[point];

            var i = indexOfHighlight(s, point);
            if (i != -1) {
                highlights.splice(i, 1);

                triggerRedrawOverlay();
            }
        }
        
        function indexOfHighlight(s, p) {
            for (var i = 0; i < highlights.length; ++i) {
                var h = highlights[i];
                if (h.series == s && h.point[0] == p[0]
                    && h.point[1] == p[1])
                    return i;
            }
            return -1;
        }
        
        function drawPointHighlight(series, point) {
            var x = point[0], y = point[1],
                axisx = series.xaxis, axisy = series.yaxis;
            
            if (x < axisx.min || x > axisx.max || y < axisy.min || y > axisy.max)
                return;
            
            var pointRadius = series.points.radius + series.points.lineWidth / 2;
            octx.lineWidth = pointRadius;
            octx.strokeStyle = $.color.parse(series.color).scale('a', 0.5).toString();
            var radius = 1.5 * pointRadius;
            octx.beginPath();
            octx.arc(axisx.p2c(x), axisy.p2c(y), radius, 0, 2 * Math.PI, false);
            octx.stroke();
        }

        function drawBarHighlight(series, point) {
            octx.lineWidth = series.bars.lineWidth;
            octx.strokeStyle = $.color.parse(series.color).scale('a', 0.5).toString();
            var fillStyle = $.color.parse(series.color).scale('a', 0.5).toString();
            var barLeft = series.bars.align == "left" ? 0 : -series.bars.barWidth/2;
            drawBar(point[0], point[1], point[2] || 0, barLeft, barLeft + series.bars.barWidth,
                    0, function () { return fillStyle; }, series.xaxis, series.yaxis, octx, series.bars.horizontal);
        }

        function getColorOrGradient(spec, bottom, top, defaultColor) {
            if (typeof spec == "string")
                return spec;
            else {
                // assume this is a gradient spec; IE currently only
                // supports a simple vertical gradient properly, so that's
                // what we support too
                var gradient = ctx.createLinearGradient(0, top, 0, bottom);
                
                for (var i = 0, l = spec.colors.length; i < l; ++i) {
                    var c = spec.colors[i];
                    if (typeof c != "string") {
                        var co = $.color.parse(defaultColor);
                        if (c.brightness != null)
                            co = co.scale('rgb', c.brightness)
                        if (c.opacity != null)
                            co.a *= c.opacity;
                        c = co.toString();
                    }
                    gradient.addColorStop(i / (l - 1), c);
                }
                
                return gradient;
            }
        }
    }

    $.plot = function(placeholder, data, options) {
        var plot = new Plot($(placeholder), data, options, $.plot.plugins);
        /*var t0 = new Date();
        var t1 = new Date();
        var tstr = "time used (msecs): " + (t1.getTime() - t0.getTime())
        if (window.console)
            console.log(tstr);
        else
            alert(tstr);*/
        return plot;
    };

    $.plot.plugins = [];

    // returns a string with the date d formatted according to fmt
    $.plot.formatDate = function(d, fmt, monthNames) {
        var leftPad = function(n) {
            n = "" + n;
            return n.length == 1 ? "0" + n : n;
        };
        
        var r = [];
        var escape = false;
        var hours = d.getUTCHours();
        var isAM = hours < 12;
        if (monthNames == null)
            monthNames = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"];

        if (fmt.search(/%p|%P/) != -1) {
            if (hours > 12) {
                hours = hours - 12;
            } else if (hours == 0) {
                hours = 12;
            }
        }
        for (var i = 0; i < fmt.length; ++i) {
            var c = fmt.charAt(i);
            
            if (escape) {
                switch (c) {
                case 'h': c = "" + hours; break;
                case 'H': c = leftPad(hours); break;
                case 'M': c = leftPad(d.getUTCMinutes()); break;
                case 'S': c = leftPad(d.getUTCSeconds()); break;
                case 'd': c = "" + d.getUTCDate(); break;
                case 'm': c = "" + (d.getUTCMonth() + 1); break;
                case 'y': c = "" + d.getUTCFullYear(); break;
                case 'b': c = "" + monthNames[d.getUTCMonth()]; break;
                case 'p': c = (isAM) ? ("" + "am") : ("" + "pm"); break;
                case 'P': c = (isAM) ? ("" + "AM") : ("" + "PM"); break;
                }
                r.push(c);
                escape = false;
            }
            else {
                if (c == "%")
                    escape = true;
                else
                    r.push(c);
            }
        }
        return r.join("");
    };
    
    // round to nearby lower multiple of base
    function floorInBase(n, base) {
        return base * Math.floor(n / base);
    }
    
})(jQuery);