$(function() {
  if ($.isController('exercise_collections')) {
    var data = $('#data').data('working-times');
    var averageWorkingTimeValue = parseFloat($('#data').data('average-working-time'));

    var margin = { top: 30, right: 40, bottom: 30, left: 50 },
      width = 720 - margin.left - margin.right,
      height = 500 - margin.top - margin.bottom;

    var x = d3.scaleBand().range([0, width]);
    var y = d3.scaleLinear().range([height, 0]);

    var xAxis = d3.axisBottom(x);
    var yAxisLeft = d3.axisLeft(y);

    var tooltip = d3.select("#graph").append("div").attr("class", "exercise-id-tooltip");

    var averageWorkingTime = d3.line()
      .x(function (d) { return x(d.index) + x.bandwidth()/2; })
      .y(function () { return y(averageWorkingTimeValue); });

    var minWorkingTime = d3.line()
      .x(function (d) { return x(d.index) + x.bandwidth()/2; })
      .y(function () { return y(0.1*averageWorkingTimeValue); });

    var maxWorkingTime = d3.line()
      .x(function (d) { return x(d.index) + x.bandwidth()/2; })
      .y(function () { return y(2*averageWorkingTimeValue); });

    var svg = d3.select('#graph')
      .append("svg")
      .attr("width", width + margin.left + margin.right)
      .attr("height", height + margin.top + margin.bottom)
      .append("g")
      .attr("transform",
        "translate(" + margin.left + "," + margin.top + ")");

    // Get the data
    data = Object.keys(data).map(function (key, index) {
      return {
        index: index,
        exercise_id: parseInt(key),
        working_time: parseFloat(data[key])
      };
    });

    // Scale the range of the data
    x.domain(data.map(function (d) { return d.index; }));
    y.domain([0, d3.max(data, function (d) { return d.working_time; })]);

    // Add the X Axis
    svg.append("g")
      .attr("class", "x axis")
      .attr("transform", "translate(0," + height + ")")
      .call(xAxis);

    // Add the Y Axis
    svg.append("g")
      .attr("class", "y axis")
      .style("fill", "steelblue")
      .call(yAxisLeft);

    // Draw the bars
    svg.selectAll("bar")
      .data(data)
      .enter()
      .append("rect")
      .attr("class", "value-bar")
      .on("mousemove", function (d){
        tooltip
          .style("left", d3.event.pageX - 50 + "px")
          .style("top", d3.event.pageY + 50 + "px")
          .style("display", "inline-block")
          .html("<%= I18n.t('activerecord.models.exercise.one') %> ID: " + d.exercise_id + "<br>" +
            "<%= I18n.t('exercises.statistics.average_worktime') %>: " + d.working_time + "s");
      })
      .on("mouseout", function (){ tooltip.style("display", "none");})
      .on("click", function (d) {
        window.location.href = "/exercises/" + d.exercise_id + "/statistics";
      })
      .attr("x", function (d) { return x(d.index); })
      .attr("width", x.bandwidth())
      .attr("y", function (d) { return y(d.working_time); })
      .attr("height", function (d) { return height - y(d.working_time); });

    // Add the average working time path
    svg.append("path")
      .datum(data)
      .attr("class", "line average-working-time")
      .attr("d", averageWorkingTime);

    // Add the anomaly paths (min/max average exercise working time)
    svg.append("path")
      .datum(data)
      .attr("class", "line minimum-working-time")
      .attr("d", minWorkingTime);
    svg.append("path")
      .datum(data)
      .attr("class", "line maximum-working-time")
      .attr("d", maxWorkingTime);
  }
});