/* *
 * Dependency wheel module
 *
 * (c) 2018-2019 Torstein Honsi
 *
 * License: www.highcharts.com/license
 */

'use strict';

import H from '../parts/Globals.js';
import '../parts/Utilities.js';
import '../parts/Options.js';
import '../mixins/nodes.js';

var base = H.seriesTypes.sankey.prototype;

/**
 * @private
 * @class
 * @name Highcharts.seriesTypes.dependencywheel
 *
 * @augments Highcharts.seriesTypes.sankey
 */
H.seriesType(
    'dependencywheel',
    'sankey',
    /**
     * A dependency wheel chart is a type of flow diagram, where all nodes are
     * laid out in a circle, and the flow between the are drawn as link bands.
     *
     * @sample highcharts/demo/dependency-wheel/
     *         Dependency wheel
     *
     * @extends      plotOptions.sankey
     * @since        7.1.0
     * @product      highcharts
     * @optionparent plotOptions.dependencywheel
     */
    {
        /**
         * The center of the wheel relative to the plot area. Can be
         * percentages or pixel values. The default behaviour is to
         * center the wheel inside the plot area.
         *
         * @type    {Array<number|string|null>}
         * @default [null, null]
         * @product highcharts
         */
        center: [null, null],
        curveFactor: 0.6,

        /**
         * The start angle of the dependency wheel, in degrees where 0 is up.
         */
        startAngle: 0
    }, {
        orderNodes: false,
        getCenter: H.seriesTypes.pie.prototype.getCenter,

        // Dependency wheel has only one column, it runs along the perimeter
        createNodeColumns: function () {
            var columns = [this.createNodeColumn()];
            this.nodes.forEach(function (node) {
                node.column = 0;
                columns[0].push(node);
            });
            return columns;
        },

        // Translate from vertical pixels to perimeter
        getNodePadding: function () {
            return this.options.nodePadding / Math.PI;
        },

        createNode: function (id) {
            var node = base.createNode.call(this, id);
            node.index = this.nodes.length - 1;

            // Return the sum of incoming and outgoing links
            node.getSum = function () {
                return node.linksFrom.concat(node.linksTo)
                    .reduce(function (acc, link) {
                        return acc + link.weight;
                    }, 0);
            };

            // Get the offset in weight values of a point/link.
            node.offset = function (point) {

                var offset = 0,
                    i,
                    links = node.linksFrom.concat(node.linksTo),
                    sliced;

                function otherNode(link) {
                    if (link.fromNode === node) {
                        return link.toNode;
                    }
                    return link.fromNode;
                }

                // Sort and slice the links to avoid links going out of each
                // node crossing each other.
                links.sort(function (a, b) {
                    return otherNode(a).index - otherNode(b).index;
                });
                for (i = 0; i < links.length; i++) {
                    if (otherNode(links[i]).index > node.index) {
                        links = links.slice(0, i).reverse().concat(
                            links.slice(i).reverse()
                        );
                        sliced = true;
                        break;
                    }
                }
                if (!sliced) {
                    links.reverse();
                }

                for (i = 0; i < links.length; i++) {
                    if (links[i] === point) {
                        return offset;
                    }
                    offset += links[i].weight;
                }
            };

            return node;
        },

        // @todo: Override the refactored sankey translateLink and translateNode
        // functions instead of the whole translate function
        translate: function () {

            var options = this.options,
                factor = 2 * Math.PI /
                    (this.chart.plotHeight + this.getNodePadding()),
                center = this.getCenter(),
                startAngle = (options.startAngle - 90) * H.deg2rad;

            base.translate.call(this);

            this.nodeColumns[0].forEach(function (node) {
                var shapeArgs = node.shapeArgs,
                    centerX = center[0],
                    centerY = center[1],
                    r = center[2] / 2,
                    innerR = r - options.nodeWidth,
                    start = startAngle + factor * shapeArgs.y,
                    end = startAngle +
                        factor * (shapeArgs.y + shapeArgs.height);

                // Middle angle
                node.angle = start + (end - start) / 2;

                node.shapeType = 'arc';
                node.shapeArgs = {
                    x: centerX,
                    y: centerY,
                    r: r,
                    innerR: innerR,
                    start: start,
                    end: end
                };

                node.dlBox = {
                    x: centerX + Math.cos((start + end) / 2) * (r + innerR) / 2,
                    y: centerY + Math.sin((start + end) / 2) * (r + innerR) / 2,
                    width: 1,
                    height: 1
                };

                // Draw the links from this node
                node.linksFrom.forEach(function (point) {
                    var distance;
                    var corners = point.linkBase.map(function (top, i) {
                        var angle = factor * top,
                            x = Math.cos(startAngle + angle) * (innerR + 1),
                            y = Math.sin(startAngle + angle) * (innerR + 1),
                            curveFactor = options.curveFactor;

                        // The distance between the from and to node along the
                        // perimeter. This affect how curved the link is, so
                        // that links between neighbours don't extend too far
                        // towards the center.
                        distance = Math.abs(
                            point.linkBase[3 - i] * factor - angle
                        );
                        if (distance > Math.PI) {
                            distance = 2 * Math.PI - distance;
                        }
                        distance = distance * innerR;
                        if (distance < innerR) {
                            curveFactor *= (distance / innerR);
                        }


                        return {
                            x: centerX + x,
                            y: centerY + y,
                            cpX: centerX + (1 - curveFactor) * x,
                            cpY: centerY + (1 - curveFactor) * y
                        };
                    });

                    point.shapeArgs = {
                        d: [
                            'M',
                            corners[0].x, corners[0].y,
                            'A',
                            innerR, innerR,
                            0,
                            0, // long arc
                            1, // clockwise
                            corners[1].x, corners[1].y,
                            'C',
                            corners[1].cpX, corners[1].cpY,
                            corners[2].cpX, corners[2].cpY,
                            corners[2].x, corners[2].y,
                            'A',
                            innerR, innerR,
                            0,
                            0,
                            1,
                            corners[3].x, corners[3].y,
                            'C',
                            corners[3].cpX, corners[3].cpY,
                            corners[0].cpX, corners[0].cpY,
                            corners[0].x, corners[0].y
                        ]
                    };

                });

            });
        },

        animate: function (init) {
            if (!init) {
                var duration = H.animObject(this.options.animation).duration,
                    step = (duration / 2) / this.nodes.length;
                this.nodes.forEach(function (point, i) {
                    var graphic = point.graphic;
                    if (graphic) {
                        graphic.attr({ opacity: 0 });
                        setTimeout(function () {
                            graphic.animate(
                                { opacity: 1 },
                                { duration: step }
                            );
                        }, step * i);
                    }
                }, this);
                this.points.forEach(function (point) {
                    var graphic = point.graphic;
                    if (!point.isNode && graphic) {
                        graphic.attr({ opacity: 0 })
                            .animate({
                                opacity: 1
                            }, this.options.animation);
                    }
                }, this);

                this.animate = null;
            }
        }
    },

    // Point class
    {
        setState: H.NodesMixin.setNodeState,
        // Return a text path that the data label uses
        getDataLabelPath: function (label) {
            var renderer = this.series.chart.renderer,
                shapeArgs = this.shapeArgs,
                upperHalf = this.angle < 0 || this.angle > Math.PI,
                start = shapeArgs.start,
                end = shapeArgs.end;

            if (!this.dataLabelPath) {
                this.dataLabelPath = renderer
                    .arc({ open: true })

                    // Add it inside the data label group so it gets destroyed
                    // with the label
                    .add(label);
            }

            this.dataLabelPath.attr({
                x: shapeArgs.x,
                y: shapeArgs.y,
                r: shapeArgs.r + (this.dataLabel.options.distance || 0),
                start: (upperHalf ? start : end),
                end: (upperHalf ? end : start),
                clockwise: +upperHalf
            });

            return this.dataLabelPath;
        },
        isValid: function () {
            // No null points here
            return true;
        }
    }
);

/**
 * A `dependencywheel` series. If the [type](#series.dependencywheel.type)
 * option is not specified, it is inherited from [chart.type](#chart.type).
 *
 * @extends   series,plotOptions.dependencywheel
 * @product   highcharts
 * @apioption series.dependencywheel
 */

/**
 * A collection of options for the individual nodes. The nodes in a dependency
 * diagram are auto-generated instances of `Highcharts.Point`, but options can
 * be applied here and linked by the `id`.
 *
 * @extends   series.sankey.nodes
 * @type      {Array<*>}
 * @product   highcharts
 * @excluding offset
 * @apioption series.dependencywheel.nodes
 */

/**
 * An array of data points for the series. For the `dependencywheel` series
 * type, points can be given in the following way:
 *
 * An array of objects with named values. The following snippet shows only a
 * few settings, see the complete options set below. If the total number of data
 * points exceeds the series' [turboThreshold](#series.area.turboThreshold),
 * this option is not available.
 *
 *  ```js
 *     data: [{
 *         from: 'Category1',
 *         to: 'Category2',
 *         weight: 2
 *     }, {
 *         from: 'Category1',
 *         to: 'Category3',
 *         weight: 5
 *     }]
 *  ```
 *
 * @type      {Array<*>}
 * @extends   series.sankey.data
 * @product   highcharts
 * @excluding outgoing, dataLabels
 * @apioption series.dependencywheel.data
 */

/**
 * Individual data label for each node. The options are the same as
 * the ones for [series.dependencywheel.dataLabels](#series.dependencywheel.dataLabels).
 *
 * @apioption series.dependencywheel.nodes.dataLabels
 */
