'use strict';
import H from '../../parts/Globals.js';
import '../../parts/Utilities.js';

var Annotation = H.Annotation,
    MockPoint = Annotation.MockPoint,
    Tunnel = Annotation.types.tunnel;

var createPathDGenerator = function (retracementIndex, isBackground) {
    return function () {
        var annotation = this.annotation,
            leftTop = this.anchor(
                annotation.startRetracements[retracementIndex]
            ).absolutePosition,
            rightTop = this.anchor(
                annotation.endRetracements[retracementIndex]
            ).absolutePosition,
            d = [
                'M',
                Math.round(leftTop.x),
                Math.round(leftTop.y),
                'L',
                Math.round(rightTop.x),
                Math.round(rightTop.y)
            ],
            rightBottom,
            leftBottom;

        if (isBackground) {
            rightBottom = this.anchor(
                annotation.endRetracements[retracementIndex - 1]
            ).absolutePosition;

            leftBottom = this.anchor(
                annotation.startRetracements[retracementIndex - 1]
            ).absolutePosition;

            d.push(
                'L',
                Math.round(rightBottom.x),
                Math.round(rightBottom.y),
                'L',
                Math.round(leftBottom.x),
                Math.round(leftBottom.y)
            );
        }

        return d;
    };
};

/**
 * @class
 * @extends Annotation.Tunnel
 * @memberOf Annotation
 **/
function Fibonacci() {
    this.startRetracements = [];
    this.endRetracements = [];

    Tunnel.apply(this, arguments);
}

Fibonacci.levels = [0, 0.236, 0.382, 0.5, 0.618, 0.786, 1];

H.extendAnnotation(Fibonacci, Tunnel,
    /** @lends Annotation.Fibonacci# */
    {
        linkPoints: function () {
            Tunnel.prototype.linkPoints.call(this);

            this.linkRetracementsPoints();
        },

        linkRetracementsPoints: function () {
            var points = this.points,
                startDiff = points[0].y - points[3].y,
                endDiff = points[1].y - points[2].y,
                startX = points[0].x,
                endX = points[1].x;

            Fibonacci.levels.forEach(function (level, i) {
                var startRetracement = points[0].y - startDiff * level,
                    endRetracement = points[1].y - endDiff * level;

                this.linkRetracementPoint(
                    i,
                    startX,
                    startRetracement,
                    this.startRetracements
                );

                this.linkRetracementPoint(
                    i,
                    endX,
                    endRetracement,
                    this.endRetracements
                );
            }, this);
        },

        linkRetracementPoint: function (
            pointIndex,
            x,
            y,
            retracements
        ) {
            var point = retracements[pointIndex],
                typeOptions = this.options.typeOptions;

            if (!point) {
                retracements[pointIndex] = new MockPoint(
                    this.chart,
                    this,
                    {
                        x: x,
                        y: y,
                        xAxis: typeOptions.xAxis,
                        yAxis: typeOptions.yAxis
                    }
                );
            } else {
                point.options.x = x;
                point.options.y = y;

                point.refresh();
            }
        },

        addShapes: function () {
            Fibonacci.levels.forEach(function (level, i) {
                this.initShape({
                    type: 'path',
                    d: createPathDGenerator(i)
                }, false);

                if (i > 0) {
                    this.initShape({
                        type: 'path',
                        fill: this.options.typeOptions.backgroundColors[i - 1],
                        strokeWidth: 0,
                        d: createPathDGenerator(i, true)
                    });
                }
            }, this);
        },

        addLabels: function () {
            Fibonacci.levels.forEach(function (level, i) {
                var options = this.options.typeOptions,
                    label = this.initLabel(
                        H.merge(options.labels[i], {
                            point: function (target) {
                                var point = MockPoint.pointToOptions(
                                    target.annotation.startRetracements[i]
                                );

                                return point;
                            },
                            text: level.toString()
                        })
                    );

                options.labels[i] = label.options;
            }, this);
        }
    },

    /**
     * A fibonacci annotation.
     *
     * @sample highcharts/annotations-advanced/fibonacci/
     *         Fibonacci
     *
     * @extends      annotations.crookedLine
     * @product      highstock
     * @optionparent annotations.fibonacci
     */
    {
        typeOptions: {
            /**
             * The height of the fibonacci in terms of yAxis.
             */
            height: 2,

            /**
             * An array of background colors:
             * Default to:
             * ```
             * [
             * 'rgba(130, 170, 255, 0.4)',
             * 'rgba(139, 191, 216, 0.4)',
             * 'rgba(150, 216, 192, 0.4)',
             * 'rgba(156, 229, 161, 0.4)',
             * 'rgba(162, 241, 130, 0.4)',
             * 'rgba(169, 255, 101, 0.4)'
             * ]
             * ```
             */
            backgroundColors: [
                'rgba(130, 170, 255, 0.4)',
                'rgba(139, 191, 216, 0.4)',
                'rgba(150, 216, 192, 0.4)',
                'rgba(156, 229, 161, 0.4)',
                'rgba(162, 241, 130, 0.4)',
                'rgba(169, 255, 101, 0.4)'
            ],

            /**
             * The color of line.
             */
            lineColor: 'grey',

            /**
             * An array of colors for the lines.
             */
            lineColors: [],

            /**
             * An array with options for the labels.
             *
             * @type      {Array<object>}
             * @extends   annotations.crookedLine.labelOptions
             * @apioption annotations.fibonacci.typeOptions.labels
             */
            labels: []
        },

        labelOptions: {
            allowOverlap: true,
            align: 'right',
            backgroundColor: 'none',
            borderWidth: 0,
            crop: false,
            overflow: 'none',
            shape: 'rect',
            style: {
                color: 'grey'
            },
            verticalAlign: 'middle',
            y: 0
        }
    });

Annotation.types.fibonacci = Fibonacci;

export default Fibonacci;
