mermaid/src/diagrams/gantt/ganttRenderer.js

var w = 1600;
var h = 800;


var svg = d3.selectAll(".svg")
    //.selectAll("svg")
    .append("svg")
    .attr("width", w)
    .attr("height", h)
    .attr("class", "svg");

// http://codepen.io/anon/pen/azLvWR

var taskArray = [
    {
        task: "conceptualize",
        type: "development",
        startTime: "2013-1-28", //year/month/day
        endTime: "2013-2-1",
        details: "This actually didn't take any conceptualization"
    },

    {
        task: "sketch",
        type: "development",
        startTime: "2013-2-1",
        endTime: "2013-2-6",
        details: "No sketching either, really"
    },

    {
        task: "color profiles",
        type: "development",
        startTime: "2013-2-6",
        endTime: "2013-2-9"
    },

    {
        task: "HTML",
        type: "coding",
        startTime: "2013-2-2",
        endTime: "2013-2-6",
        details: "all three lines of it"
    },

    {
        task: "write the JS",
        type: "coding",
        startTime: "2013-2-6",
        endTime: "2013-2-9"
    },

    {
        task: "advertise",
        type: "promotion",
        startTime: "2013-2-9",
        endTime: "2013-2-12",
        details: "This counts, right?"
    },

    {
        task: "spam links",
        type: "promotion",
        startTime: "2013-2-12",
        endTime: "2013-2-14"
    },
    {
        task: "eat",
        type: "celebration",
        startTime: "2013-2-8",
        endTime: "2013-2-13",
        details: "All the things"
    },

    {
        task: "crying",
        type: "development",
        startTime: "2013-2-13",
        endTime: "2013-2-16"
    },

];

var dateFormat = d3.time.format("%Y-%m-%d");

var timeScale = d3.time.scale()
    .domain([d3.min(taskArray, function(d) {return dateFormat.parse(d.startTime);}),
        d3.max(taskArray, function(d) {return dateFormat.parse(d.endTime);})])
    .range([0,w-150]);

var categories = [];

for (var i = 0; i < taskArray.length; i++){
    categories.push(taskArray[i].type);
}

var catsUnfiltered = categories; //for vert labels

categories = checkUnique(categories);


makeGant(taskArray, w, h);

var title = svg.append("text")
    .text("Gantt Chart Process")
    .attr("x", w/2)
    .attr("y", 25)
    .attr("text-anchor", "middle")
    .attr("font-size", 18)
    .attr("fill", "#009FFC");



function makeGant(tasks, pageWidth, pageHeight){

    var barHeight = 20;
    var gap = barHeight + 4;
    var topPadding = 75;
    var sidePadding = 75;

    var colorScale = d3.scale.linear()
        .domain([0, categories.length])
        .range(["#00B9FA", "#F95002"])
        .interpolate(d3.interpolateHcl);

    makeGrid(sidePadding, topPadding, pageWidth, pageHeight);
    drawRects(tasks, gap, topPadding, sidePadding, barHeight, colorScale, pageWidth, pageHeight);
    vertLabels(gap, topPadding, sidePadding, barHeight, colorScale);

}


function drawRects(theArray, theGap, theTopPad, theSidePad, theBarHeight, theColorScale, w, h){

    var bigRects = svg.append("g")
        .selectAll("rect")
        .data(theArray)
        .enter()
        .append("rect")
        .attr("x", 0)
        .attr("y", function(d, i){
            return i*theGap + theTopPad - 2;
        })
        .attr("width", function(d){
            return w-theSidePad/2;
        })
        .attr("height", theGap)
        .attr("stroke", "none")
        .attr("fill", function(d){
            for (var i = 0; i < categories.length; i++){
                if (d.type == categories[i]){
                    return d3.rgb(theColorScale(i));
                }
            }
        })
        .attr("opacity", 0.2);


    var rectangles = svg.append('g')
        .selectAll("rect")
        .data(theArray)
        .enter();


    var innerRects = rectangles.append("rect")
        .attr("rx", 3)
        .attr("ry", 3)
        .attr("x", function(d){
            return timeScale(dateFormat.parse(d.startTime)) + theSidePad;
        })
        .attr("y", function(d, i){
            return i*theGap + theTopPad;
        })
        .attr("width", function(d){
            return (timeScale(dateFormat.parse(d.endTime))-timeScale(dateFormat.parse(d.startTime)));
        })
        .attr("height", theBarHeight)
        .attr("stroke", "none")
        .attr("fill", function(d){
            for (var i = 0; i < categories.length; i++){
                if (d.type == categories[i]){
                    return d3.rgb(theColorScale(i));
                }
            }
        });


    var rectText = rectangles.append("text")
        .text(function(d){
            return d.task;
        })
        .attr("x", function(d){
            return (timeScale(dateFormat.parse(d.endTime))-timeScale(dateFormat.parse(d.startTime)))/2 + timeScale(dateFormat.parse(d.startTime)) + theSidePad;
        })
        .attr("y", function(d, i){
            return i*theGap + 14+ theTopPad;
        })
        .attr("font-size", 11)
        .attr("text-anchor", "middle")
        .attr("text-height", theBarHeight)
        .attr("fill", "#fff");


    rectText.on('mouseover', function(e) {
        // console.log(this.x.animVal.getItem(this));
        var tag = "";

        if (typeof d3.select(this).data()[0].details !== 'undefined'){
            tag = "Task: " + d3.select(this).data()[0].task + "<br/>" +
            "Type: " + d3.select(this).data()[0].type + "<br/>" +
            "Starts: " + d3.select(this).data()[0].startTime + "<br/>" +
            "Ends: " + d3.select(this).data()[0].endTime + "<br/>" +
            "Details: " + d3.select(this).data()[0].details;
        } else {
            tag = "Task: " + d3.select(this).data()[0].task + "<br/>" +
            "Type: " + d3.select(this).data()[0].type + "<br/>" +
            "Starts: " + d3.select(this).data()[0].startTime + "<br/>" +
            "Ends: " + d3.select(this).data()[0].endTime;
        }
        var output = document.getElementById("tag");

        var x = this.x.animVal.getItem(this) + "px";
        var y = this.y.animVal.getItem(this) + 25 + "px";

        output.innerHTML = tag;
        output.style.top = y;
        output.style.left = x;
        output.style.display = "block";
    }).on('mouseout', function() {
        var output = document.getElementById("tag");
        output.style.display = "none";
    });


    innerRects.on('mouseover', function(e) {
        //console.log(this);
        var tag = "";

        if (typeof d3.select(this).data()[0].details !== 'undefined'){
            tag = "Task: " + d3.select(this).data()[0].task + "<br/>" +
            "Type: " + d3.select(this).data()[0].type + "<br/>" +
            "Starts: " + d3.select(this).data()[0].startTime + "<br/>" +
            "Ends: " + d3.select(this).data()[0].endTime + "<br/>" +
            "Details: " + d3.select(this).data()[0].details;
        } else {
            tag = "Task: " + d3.select(this).data()[0].task + "<br/>" +
            "Type: " + d3.select(this).data()[0].type + "<br/>" +
            "Starts: " + d3.select(this).data()[0].startTime + "<br/>" +
            "Ends: " + d3.select(this).data()[0].endTime;
        }
        var output = document.getElementById("tag");

        var x = (this.x.animVal.value + this.width.animVal.value/2) + "px";
        var y = this.y.animVal.value + 25 + "px";

        output.innerHTML = tag;
        output.style.top = y;
        output.style.left = x;
        output.style.display = "block";
    }).on('mouseout', function() {
        var output = document.getElementById("tag");
        output.style.display = "none";

    });



}


function makeGrid(theSidePad, theTopPad, w, h){

    var xAxis = d3.svg.axis()
        .scale(timeScale)
        .orient('bottom')
        .ticks(d3.time.weeks, 5)
        .tickSize(-h+theTopPad+20, 0, 0)
        .tickFormat(d3.time.format('%d %b'));

    var grid = svg.append('g')
        .attr('class', 'grid')
        .attr('transform', 'translate(' +theSidePad + ', ' + (h - 50) + ')')
        .call(xAxis)
        .selectAll("text")
        .style("text-anchor", "middle")
        .attr("fill", "#000")
        .attr("stroke", "none")
        .attr("font-size", 10)
        .attr("dy", "1em");
}

function vertLabels(theGap, theTopPad, theSidePad, theBarHeight, theColorScale){
    var numOccurances = [];
    var prevGap = 0;

    for (var i = 0; i < categories.length; i++){
        numOccurances[i] = [categories[i], getCount(categories[i], catsUnfiltered)];
    }

    var axisText = svg.append("g") //without doing this, impossible to put grid lines behind text
        .selectAll("text")
        .data(numOccurances)
        .enter()
        .append("text")
        .text(function(d){
            return d[0];
        })
        .attr("x", 10)
        .attr("y", function(d, i){
            if (i > 0){
                for (var j = 0; j < i; j++){
                    prevGap += numOccurances[i-1][1];
                    // console.log(prevGap);
                    return d[1]*theGap/2 + prevGap*theGap + theTopPad;
                }
            } else{
                return d[1]*theGap/2 + theTopPad;
            }
        })
        .attr("font-size", 11)
        .attr("text-anchor", "start")
        .attr("text-height", 14)
        .attr("fill", function(d){
            for (var i = 0; i < categories.length; i++){
                if (d[0] == categories[i]){
                    //  console.log("true!");
                    return d3.rgb(theColorScale(i)).darker();
                }
            }
        });

}

//from this stackexchange question: http://stackoverflow.com/questions/1890203/unique-for-arrays-in-javascript
function checkUnique(arr) {
    var hash = {}, result = [];
    for ( var i = 0, l = arr.length; i < l; ++i ) {
        if ( !hash.hasOwnProperty(arr[i]) ) { //it works with objects! in FF, at least
            hash[ arr[i] ] = true;
            result.push(arr[i]);
        }
    }
    return result;
}

//from this stackexchange question: http://stackoverflow.com/questions/14227981/count-how-many-strings-in-an-array-have-duplicates-in-the-same-array
function getCounts(arr) {
    var i = arr.length, // var to loop over
        obj = {}; // obj to store results
    while (i) obj[arr[--i]] = (obj[arr[i]] || 0) + 1; // count occurrences
    return obj;
}

// get specific from everything
function getCount(word, arr) {
    return getCounts(arr)[word] || 0;
}