import { Points } from '../../utils.js'
import { EventHandler } from './utils.js'
import { FlagPolygon } from '../graphics/label.js'
import { DeepZoomMap } from './map.js'
import { PIXIUtils } from '../../../../js/pixi/utils.js'

/**
 * * GeoGraphics are graphical objects, that does not store the graphics information
 * in screen space, but in geographical coordinates. Therefore GeoGraphics must be
 * placed on GeoLayers to work properly.
 *
 * (Note: As GeoLayers are always children of a map layer. When the map is changed
 * all GeoLayers are notified via the 'adaptTo(map)' method.)
 *
 * The geolayers forward this 'adaptTo' to all children that are GeoGraphics.
 * Which adjust their so called 'point' data to the new map.
 *
 * @export
 * @class GeoGraphics
 */
export class GeoGraphics {
    constructor(coordinates, { scale = 1, onDraw = null, onDrawEnd = null, debug = false } = {}) {
        this._coordinates = coordinates
        this.debug = debug
        this.graphics = new PIXI.Graphics()
        this.scale = scale
        this.drawHandler = new EventHandler('onDraw', { listeners: onDraw })
        this.drawEndHandler = new EventHandler('onDrawEnd', { listeners: onDrawEnd })
        this._points = null
        this._position = null
    }

    /**
     * The coordinates of the geographics.
     *
     * @member {array}
     * @readonly
     * @memberof GeoGraphics
     */
    get coordinates() {
        return this._coordinates
    }

    clone() {
        console.error(`Call of abstract method clone(). Overwrite in subclass.`, this)
    }

    _cloneOptions() {
        return {
            debug: this.debug,
            scale: this.scale
        }
    }

    /**
     * The _adaptCoordinates is called first by the adaptTo Method.
     * Here all coordinates are transformed into point coordinates.
     * This must be overloaded in subclass.
     *
     * @abstract
     */
    _adaptCoordinates(map) {
        console.error(`Call of abstract method _adaptCoordinates(map). Overwrite in subclass.`, this)
    }

    /**
     * Gets all screen points in a single array.
     *
     * @abstract
     * @returns {array} - Array of all points in the GeoGraphic.
     */
    _getPoints() {
        console.error(`Call of abstract method _getPoints(func). Overwrite in subclass.`, this)
    }

    /**
     * Manipulates all points depending on a function.
     * Mainly used to transform points to local space.
     *
     * @abstract
     * @param {function} func
     * @memberof GeoGraphics
     */
    _manipulatePoints(func) {
        console.error(`Call of abstract method _manipulatePoints(func). Overwrite in subclass.`, this)
    }

    /**
     * The _draw method is called last on adaptation. It creates the GraphicData
     * of the specified subclass. To manipulate the style of the graphic, hook an onDraw listener
     * to the GeoGraphics object. It is called before the _draw and lets the user modify color and
     * lineStyle of the drawn object.
     *
     * Note: It could also be used for more radical manipulations on the graphics object.
     * But this should be used with care.
     *
     * @abstract
     */
    _draw() {
        console.error(`Call of abstract method _draw(). Overwrite in subclass.`, this)
    }

    /**
     * Called by the containing geo layer, when the map changes.
     */
    adaptTo(map) {
        this._points = this._adaptCoordinates(map)
        this._updatePosition()
        this.draw()
    }

    /**
     * Redraws the graphics.
     *
     * This should be only called if you require an redraw independent of an adapt.
     *
     * @memberof GeoGraphics
     */
    draw() {
        this._prepareDraw()
        this.drawHandler.call(this, this.graphics)
        this._draw()
        this.drawEndHandler.call(this, this.graphics)
    }

    /**
     * Retrieves the point data.
     * Note: This data changes on adaptation.
     */
    get points() {
        return this._points
    }

    /**
     * Returns the screen position of the GeoGraphics.
     */
    get position() {
        return this._position
    }

    get layer() {
        return this._layer ? this._layer : null
    }

    setLayer(layer) {
        this._layer = layer
    }

    /**
     * Map of the containing layer. Null if on no layer.
     *
     * @readonly
     * @memberof GeoGraphics
     */
    get map() {
        let map = null
        if (this.mapLayer) {
            map = this.mapLayer.map
        }
        return map
    }

    /**
     * MapLayer of the containing layer. Null if on no layer.
     *
     * @member {MapLayer}
     * @readonly
     * @memberof GeoGraphics
     */
    get mapLayer() {
        let mapLayer = null
        if (this.layer) {
            mapLayer = this.layer.mapLayer
        }
        return mapLayer
    }

    /**
     *  Prepare draw is a private function, that prepares the graphics
     * for the next draw call. It also fires the drawHandler.
     *
     * @private
     * @memberof GeoGraphics
     */
    _prepareDraw() {
        this.graphics.clear()
        /*
           Set a fillcolor and a stroke style for
           debugging. Can be overloaded using the onDraw 
           event function.
       */
        if (this.debug) this.graphics.beginFill(0xff00ff)
    }

    _updatePosition() {
        let points = this._getPoints()
        this._position = GeoGraphics.calculateCenterOfMass(points)
        this._manipulatePoints(point => {
            point = Points.subtract(point, this._position)
            return point
        })
        this.graphics.position = this._position
    }

    /**
     * Calculates the center of Mass for a set of points.
     *
     * @static
     * @param {Array} points - Array of points in the format {x: a, y:b}
     * @returns {object} - Returns a point containing the center of mass of the polygon.
     * @memberof GeoGraphics
     */
    static calculateCenterOfMass(points) {
        let com = new PIXI.Point()
        points.forEach(p => {
            let point = new PIXI.Point(p.x, p.y)
            com = Points.add(com, point)
        })
        return Points.multiplyScalar(com, 1 / points.length)
    }
}

/**
 * Represents a single point on the Map.
 *
 * This GeoGraphics does not provide any visual representation.
 * Draw the desired shape in the onDraw callback.
 *
 * @export
 * @class GeoPoint
 * @extends {GeoGraphics}
 */
export class GeoPoint extends GeoGraphics {
    clone() {
        return new GeoPoint(this.coordinates, this._cloneOptions())
    }

    _adaptCoordinates(map) {
        let scale = 1

        if (map instanceof DeepZoomMap) {
            scale = map.image.scale.x
        }

        scale = scale / 4

        return map.coordinatesToPoint(this.coordinates)
    }

    _getPoints() {
        return [this.points]
    }

    _manipulatePoints(func) {
        this._points = func(this._points)
    }

    _draw() {}
}

/**
 * Represensts a line between two locations.
 *
 * @export
 * @class GeoLine
 * @extends {GeoGraphics}
 */
export class GeoLine extends GeoGraphics {
    /**
     * @param {object} opts - Optional values
     * @param {array} [opts.points=[]] - Initial points of the geo shape.
     * @param {boolean} [closed=false] - Defines if the
     */
    constructor(coordinates, { closed = false, size = 1, onDraw = null } = {}) {
        super(coordinates, {
            size,
            onDraw
        })

        this._closed = closed
    }

    clone() {
        return new GeoLine(this.coordinates, this._cloneOptions)
    }

    _cloneOptions() {
        let options = super._cloneOptions()
        Object.assign(options, {
            closed: this.closed
        })
    }

    /**
     * Adds a point to the geo line.
     */
    addPoint(coordinate) {
        this.coordinates.push(coordinate)
    }

    _manipulatePoints(func) {
        this.points.forEach((point, idx, array) => {
            array[idx] = func(point)
        })
    }

    _getPoints() {
        return this.points
    }

    _adaptCoordinates(map) {
        let points = []
        this.coordinates.forEach(point => {
            points.push(map.coordinatesToPoint(point))
        })
        return points
    }

    _prepareDraw() {
        this.graphics.clear()
        if (this.debug) this.graphics.lineStyle(0.5, 0xff00ff)
        this.drawHandler.call(this)
    }

    _draw() {
        /**
         * This resets the fill.
         *
         *  DISCUSS:    SO: "I'm not sure how the line should be defined.
         *              On the one hand. The line is clearly intended to
         *              represent a line and not an area. On the other hand,
         *              why should the user be prevented from using a fill for the
         *              area within the line. But if he want's a fill, why don't take
         *              a Polygon in the first place?
         *
         *              (But if it's a predefined GeoJSON object obtained through e.g. elasticsearch,
         *              then the user is not in full control of the object type and it may be a good
         *              addition to grant the user this additional design choice.)
         *
         *              The opportunity to do so would result in additional conditions, when creating the
         *              GeoGraphics of an overlay."
         * */
        this.graphics.beginFill(0, 0)

        if (this.points.length > 0) {
            this.graphics.moveTo(this.points[0].x, this.points[0].y)

            for (let i = 1; i < this.points.length; i++) {
                this.graphics.lineTo(this.points[i].x, this.points[i].y)
            }

            if (this.closed) {
                this.graphics.lineTo(this.points[0].x, this.points[0].y)
            }
        }
    }

    get closed() {
        return this._closed
    }

    set closed(val) {
        if (val != this._closed) {
            this._closed = val
            this.draw()
        }
    }
}

/**
 * Represents a shape on a map.
 *
 * @export
 * @class GeoShape
 * @extends {GeoGraphics}
 */
export class GeoShape extends GeoGraphics {
    clone() {
        return new GeoShape(this.coordinates, this._cloneOptions)
    }

    _manipulatePoints(func) {
        this.constructor._manipulatePoints(this.points, func)
    }

    /**
     * Mets the requirements for the _manipulatePointsMethod().
     * Primarily used in subclasses to get the processing steps from
     * their superclass.
     *
     * @static
     * @protected
     * @param {Array.<PIXI.Points>} points - The points array that shold be manipulated.
     * @param {function} func   - The function that changes the single point value. Has to return a new point.
     * @memberof GeoShape
     */
    static _manipulatePoints(points, func) {
        points.forEach((pointArray, arrIdx) => {
            pointArray.forEach((point, idx) => {
                points[arrIdx][idx] = func(point)
            })
        })
    }

    _getPoints() {
        return this.constructor._getPointsFrom(this.points)
    }

    /**
     * Returns all points of a polygon array.
     * Useful for when getting sub polygons in child class.
     */
    static _getPointsFrom(shape) {
        let concatArray = []
        shape.forEach(array => {
            concatArray = concatArray.concat(array)
        })

        return concatArray
    }

    _adaptCoordinates(map) {
        let val = this.constructor._adaptPoint(this.coordinates, map)
        return val
    }

    static _adaptPoint(coordinates, map) {
        return coordinates.map(array => {
            return array.map(point => {
                return map.coordinatesToPoint(point)
            })
        })
    }

    _draw() {
        this._drawFrom(this.points)
        this.graphics.position = this.position
    }

    _drawFrom(shape) {
        const { polygon, hole } = this.constructor._pointsToShape(shape)
        this._drawShape(polygon, hole)
    }

    /**
     * Separates the points array into it's two parts:
     *      - the solid polygon
     *      - a hole that is cut into the polygon (optional)
     *
     * @private
     * @returns {object} - Returns an object containing the polygon and the hole in the form of {polygon: [...PIXI.Point], hole: [...PIXI.Point]}
     */
    static _pointsToShape(points) {
        let polygon = GeoShape._transformToPIXI(points[0])
        let hole = points[1] ? GeoShape._transformToPIXI(points[1]) : []
        return { polygon, hole }
    }

    /**
     * Transform an array of poins into an array of PIXI.Points.
     * Note:    When creating PIXI.Polygons, for some reason the points
     *          need to be a PIXI.Points object (at least the first one).
     *
     * @param {array} points - Points in the form of {x:a,y:b}
     * @returns An array of PIXI.Points
     * @memberof GeoPolygon
     */
    static _transformToPIXI(points = []) {
        let polygon = []
        points.forEach(point => {
            polygon.push(new PIXI.Point(point.x, point.y))
        })

        return polygon
    }

    /**
     * Draws a single shape onto the graphics object.
     * Useful when being called from subclass.
     *
     * @protected
     * @param {Array.<PIXI.Point>} polygon - An array of PIXI.Points for drawing a polygon.
     * @param {Array.<PIXI.Point>} [hole=[]] - An Array of PIXI.Points for cutting a hole into the polygon
     * @memberof GeoShape
     */
    _drawShape(polygon, hole = []) {
        // We save the fill specified in the onDraw event handler.
        let { fill, alpha } = PIXIUtils.saveFill(this.graphics)

        /**
         * a) Draw the hole with a polygon.
         *
         * This may seem redundant to (c), but it's required (in this order(!))
         * to make the hole clickable.
         *
         * It was a bit confusing, so I made a CodePen
         * for it: https://codepen.io/Ukmasmu/pen/WJEaoK
         */
        if (hole.length > 0) {
            this.graphics.beginFill(0x0000ff, 0.0000001)
            this.graphics.drawPolygon(hole)
        }

        /**
         * b) Draw the shape.
         */
        this.graphics.beginFill(fill, alpha)
        this.graphics.drawPolygon(polygon)

        /**
         * c) Add the hole.
         */
        if (hole.length > 0) {
            this.graphics.beginHole()
            this.graphics.drawPolygon(hole)
            this.graphics.endHole()
        }
    }
}

/**
 * The MultiGraphics makes use of the other GeoGraphics to
 * create a single graphics element out of multiple different
 * GeoGraphics.
 *
 * @class GeoMultiGraphics
 * @extends {GeoGraphics}
 */
class GeoMultiGraphics extends GeoGraphics {
    /**
     * The _adaptCoordinates is called first by the adaptTo Method.
     * Here all coordinates are transformed into point coordinates.
     * This must be overloaded in subclass.
     *
     * @abstract
     */
    _adaptCoordinates(map) {}

    /**
     * Gets all screen points in a single array.
     *
     * @abstract
     * @returns {array} - Array of all points in the GeoGraphic.
     */
    _getPoints() {
        console.error(`Call of abstract method _getPoints(func). Overwrite in subclass.`, this)
    }

    /**
     * Manipulates all points depending on a function.
     * Mainly used to transform points to local space.
     *
     * @abstract
     * @param {function} func
     * @memberof GeoGraphics
     */
    _manipulatePoints(func) {
        console.error(`Call of abstract method _manipulatePoints(func). Overwrite in subclass.`, this)
    }

    /**
     * The _draw method is called last on adaptation. It creates the GraphicData
     * of the specified subclass. To manipulate the style of the graphic, hook an onDraw listener
     * to the GeoGraphics object. It is called before the _draw and lets the user modify color and
     * lineStyle of the drawn object.
     *
     * Note: It could also be used for more radical manipulations on the graphics object.
     * But this should be used with care.
     *
     * @abstract
     */
    _draw() {
        console.error(`Call of abstract method _draw(). Overwrite in subclass.`, this)
    }
}

/**
 * Text that is attatched to a GeoPoint.
 *
 * @export
 * @class GeoText
 * @extends {GeoPoint}
 */
export class GeoText extends GeoPoint {
    constructor(coordinates, text, opts) {
        super(coordinates, opts)
        this.align = opts.align
        this.textStyle = Object.assign(new PIXI.TextStyle(), opts.textStyle)
        this._text = new PIXI.Text(text, this.textStyle)

        switch (this.align) {
            case 'left':
                break
            case 'center':
                this.text.position.x -= this.text.width / 2
                break
            case 'right':
                this.text.position.x -= this.text.width
                break
            default:
                console.error('Align type is not implemented: ' + this.align + ". Use 'left', 'right' or 'center'.")
        }
        this.text.position.y -= this.text.height / 2
        this.graphics.addChild(this.text)
    }

    get text() {
        return this._text
    }

    _draw() {
        super._draw()
    }

    adaptTo(map) {
        super.adaptTo(map)
    }
}

/**
 * A geotext with a notch at a certain Position.
 *
 * TODO: This is a specialization for the Tüsch. This should be inside the Tüsch project.
 */
export class GeoFlagLabel extends GeoText {
    constructor(coordinates, text, opts) {
        super(
            coordinates,
            text,
            Object.assign(opts, {
                align: 'left'
            })
        )

        if (!opts.flag) {
            opts.flag = {}
        }

        const {
            alpha = 1,
            color = 0xffffff,
            borderAlpha = 1,
            borderColor = 0x000000,
            borderThickness = 0,
            fillNotch = false
        } = opts

        Object.assign(this, {
            alpha,
            color,
            fillNotch,
            borderAlpha,
            borderColor,
            borderThickness
        })

        this.flagOptions = Object.assign(
            {
                notchSize: 10,
                notchWidth: null,
                notchHeight: null,
                padding: { x: 0, y: 0 },
                originOffset: { x: 0, y: 0 }
            },
            opts.flag
        )

        this.border = this.borderThickness > 0

        Object.assign(this.flagOptions, {
            width: this.text.width + this.flagOptions.padding.x * 2,
            height: this.text.height + this.flagOptions.padding.y * 2
        })

        this.flagPolygon = new FlagPolygon(this.flagOptions)

        // hover effect
        //--------------------
        const duration = 0.2
        this.graphics.interactive = true
        this.graphics.on('pointerover', event => {
            TweenLite.to(this.graphics, duration, { alpha: 0.6 })
        })
        this.graphics.on('pointerout', event => {
            TweenLite.to(this.graphics, duration, { alpha: 1 })
        })
        this.graphics.on('pointerupoutside', event => {
            TweenLite.to(this.graphics, duration, { alpha: 1 })
        })
        this.graphics.on('pointercancel', event => {
            TweenLite.to(this.graphics, duration, { alpha: 1 })
        })
        this.graphics.on('pointertap', event => {
            TweenLite.to(this.graphics, duration, { alpha: 1 })
        })
        // this.graphics.on('pointerdown', event => {
        //     TweenLite.to(this.graphics, duration, { alpha: 0.45 })
        // })
        // this.graphics.on('pointerup', event => {
        //     TweenLite.to(this.graphics, duration, { alpha: 0.6 })
        // })
    }

    _draw() {
        super._draw()

        this.graphics.beginFill(this.color, this.alpha)
        this.graphics.drawPolygon(this.flagPolygon)
        this.flagPolygon.placeText(this.text, this.flagOptions.padding)

        if (this.border) {
            const lineStyle = [this.borderThickness, this.borderColor, this.borderAlpha]
            if (this.fillNotch) {
                this.graphics.beginFill(this.borderColor)
                this.graphics.drawPolygon(this.flagPolygon.notch)
                this.graphics.endFill()

                this.graphics.lineStyle(...lineStyle)
                this.graphics.drawPolygon(this.flagPolygon.rect)
                this.graphics.drawPolygon(this.flagPolygon.notch)
            } else {
                this.graphics.lineStyle(...lineStyle)
                this.graphics.drawPolygon(this.flagPolygon)
            }
        }
    }
}

/**
 * The GeoMultiShape displays multiple forms.
 *
 * @export
 * @class GeoMultiShape
 * @extends {GeoShape}
 */
export class GeoMultiShape extends GeoShape {
    static _manipulatePoints(points, func) {
        points.forEach(shape => {
            GeoShape._manipulatePoints(shape, func)
        })
    }

    static _getPointsFrom(multiShapeArray) {
        let points = []
        multiShapeArray.forEach(shape => {
            points = points.concat(GeoShape._getPointsFrom(shape))
        })
        return points
    }

    static _adaptPoint(coordinates, map) {
        let points = []
        coordinates.forEach(shape => {
            let adaptedPoint = GeoShape._adaptPoint(shape, map)
            points.push(adaptedPoint)
        })
        return points
    }

    calculateLocation() {
        let coms = []
        this.coordinates.forEach(polygon => {
            coms.push(GeoGraphics.calculateCenterOfMass(polygon))
        })

        return GeoGraphics.calculateCenterOfMass(coms)
    }

    _drawFrom(multiShape) {
        multiShape.forEach(shape => {
            super._drawFrom(shape)
        })
    }
}