// Define custom series type for displaying low/med/high values using boxplot as a base
Highcharts.seriesType('lowmedhigh', 'boxplot', {
    keys: ['low', 'median', 'high'],
    tooltip: {
        pointFormat: '<span style="color:{point.color}">\u25CF</span> {series.name}: ' +
            'Low <b>{point.low}</b> - Median <b>{point.median}</b> - High <b>{point.high}</b><br/>'
    }
}, {
    // Change point shape to a line with three crossing lines for low/median/high
    // Stroke width is hardcoded to 1 for simplicity
    drawPoints: function () {
        var series = this;
        this.points.forEach(function (point) {
            var graphic = point.graphic,
                verb = graphic ? 'animate' : 'attr',
                shapeArgs = point.shapeArgs,
                width = shapeArgs.width,
                left = Math.floor(shapeArgs.x) + 0.5,
                right = left + width,
                crispX = left + Math.round(width / 2) + 0.5,
                highPlot = Math.floor(point.highPlot) + 0.5,
                medianPlot = Math.floor(point.medianPlot) + 0.5,
                // Sneakily draw low marker even if 0
                lowPlot = Math.floor(point.lowPlot) +
                    0.5 - (point.low === 0 ? 1 : 0);

            if (point.isNull) {
                return;
            }

            if (!graphic) {
                point.graphic = graphic = series.chart.renderer.path('point').add(series.group);
            }

            graphic.attr({
                stroke: point.color || series.color,
                "stroke-width": 1
            });

            graphic[verb]({
                d: [
                    'M', left, highPlot,
                    'H', right,
                    'M', left, medianPlot,
                    'H', right,
                    'M', left, lowPlot,
                    'H', right,
                    'M', crispX, highPlot,
                    'V', lowPlot
                ]
            });
        });
    }
});

// Create chart
var chart = Highcharts.chart('container', {
    chart: {
        type: 'lowmedhigh'
    },

    title: {
        text: 'Daily company fruit consumption 2019'
    },

    accessibility: {
        point: {
            descriptionFormatter: function (point) {
                // Use default formatter for null points
                if (point.isNull) {
                    return false;
                }

                return point.category + ', low ' + point.low + ', median ' +
                    point.median + ', high ' + point.high;
            }
        },

        series: {
            descriptionFormatter: function (series) {
                return series.name + ', series ' + (series.index + 1) + ' of ' +
                    series.chart.series.length + ' with ' + series.points.length +
                    ' data points.';
            }
        },

        typeDescription: 'Low, median, high. Each data point has a low, median and high value, depicted vertically as small ticks.' // Describe the chart type to screen reader users, since this is not a traditional boxplot chart
    },

    xAxis: [{
        accessibility: {
            description: 'Months of the year'
        },
        categories: ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'],
        crosshair: true
    }],

    yAxis: {
        title: {
            text: 'Fruits consumed'
        },
        min: 0
    },

    responsive: {
        rules: [{
            condition: {
                maxWidth: 550
            },
            chartOptions: {
                xAxis: {
                    categories: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
                }
            }
        }]
    },

    tooltip: {
        shared: true
    },

    plotOptions: {
        series: {
            stickyTracking: true,
            whiskerWidth: 5
        }
    },

    series: [{
        name: 'Plums',
        data: [
            [0, 8, 19],
            [1, 11, 23],
            [3, 16, 28],
            [2, 15, 28],
            [1, 15, 27],
            [0, 9, 21],
            null,
            null,
            [1, 6, 19],
            [2, 8, 21],
            [2, 9, 22],
            [1, 11, 19]
        ]
    }, {
        name: 'Bananas',
        data: [
            [0, 3, 6],
            [1, 2, 4],
            [0, 2, 5],
            [2, 2, 5],
            [1, 3, 6],
            [0, 1, 3],
            [1, 1, 2],
            [0, 1, 3],
            [1, 1, 3],
            [0, 2, 4],
            [1, 2, 5],
            [1, 3, 5]
        ]
    }, {
        name: 'Apples',
        data: [
            [1, 4, 6],
            [2, 4, 5],
            [1, 3, 6],
            [2, 3, 6],
            [1, 3, 4],
            [0, 2, 4],
            [0, 1, 2],
            [0, 1, 2],
            [0, 1, 2],
            [0, 2, 4],
            [1, 2, 4],
            [1, 3, 4]
        ]
    }]
});

// Remove click events on container to avoid having "clickable" announced by AT
// These events are needed for custom click events, drag to zoom, and navigator
// support.
chart.container.onmousedown = null;
chart.container.onclick = null;
