import PIXIApp from '../app.js'
import { CoordinateDisplay } from './display.js'
import { MapLayer } from './geolayer.js'
import { RigidScatterContainer } from './scatter.js'
import { EventHandler } from './utils.js'
import { Points } from '../../utils.js'
import Logging from '../../logging.js'
import { MapList } from './maplist.js'

/**
 * A PIXI.Point or object in form {x,y}.
 * 
 * @typedef {Object} Point
 * @property {number} x - Indicates whether the Courage component is present.
 * @property {number} y - Indicates whether the Power component is present.
 */

/**
 * A coordinate point is a PIXI.Point or object in form {x,y} that contains map coordinates
 * instead of pixel values, where x represents the latitude and y the longitude.
 * @typedef {Object} CoordinatePoint
 * @property {number} x - Indicates whether the Courage component is present.
 * @property {number} y - Indicates whether the Power component is present.
 */

/**
 * MapApp is responsible for showing fullscreen
 * map applications.
 *
 * @export
 * @class MapApp
 * @extends {PIXIApp}
 */
export default class MapApp extends PIXIApp {
    /**
     *Creates an instance of MapApp.
     * @memberof MapApp
     */
    constructor(opts = {}) {
        super(opts)

        // Default values.
        opts = Object.assign(
            {
                debug: false,
                maps: {}, //required
                view: null, //required
                wrapper: null, // Required if you want to use DOM Overlays.
                startmap: null,
                coordsLogging: false,
                overlays: {},
                keycodes: {},
                imageMapZoomHeight: 256, //Defines the zoomvalue 1 for all image maps inside the mapapp.
                focus: null,
                zoom: 1,
                onMapChanged: null,
                onSizeChanged: null,
                onTransform: null
            },
            opts,
            {
                alpha: 0.5
            }
        )
        this.submaps = []
        this.overlayElements = new Map()
        this.debug = opts.debug
        this.fpsLogging = opts.fpsLogging
        this.keycodes = this._extractKeyCodes(opts.keycodes)
        this.coordsLogging = opts.coordsLogging
        this.overlays = opts.overlays
        this.focus = opts.focus
        this.zoom = opts.zoom
        this.wrapper = opts.wrapper

        this.onMapChanged = new EventHandler('mapChanged', {
            listeners: opts.onMapChanged
        })
        this.onSizeChanged = new EventHandler('sizeChanged', {
            listeners: opts.onSizeChanged
        })
        this.onTransform = new EventHandler('transformed', {
            listeners: opts.onTransform
        })

        /**
         * When in debug mode, this allows the user to copy the center coordinates to the clipboard.
         */
        if (this.debug) {
            this.DRAW_MODES = {
                PIXI_POINT: 0,
                PATH_MODE: 1,
                POLYGON_MODE: 2,

                getName: function(num) {
                    let result = null
                    for (const [key, val] of Object.entries(this)) {
                        if (val == num) result = key
                    }
                    return result
                }
            }
            this.drawMode = this.DRAW_MODES.PIXI_POINT
            this.drawData = []
        }

        this.mapList = new MapList(opts.startmap ? opts.startmap : null, opts.maps ? opts.maps : {})

        this._setupKeyboardUtils()
    }

    /**
     * Log boundaries for a shown map.
     * This is for development purposes only, if you want
     * to find the boundaries of a shown map.
     *
     * @memberof MapApp
     */
    logMapBoundaries() {
        let map = this.mapLayer.map

        let boundaries = {
            min: this.mapLayer.mapview.coordinatesFromWindowPoint(map, { x: 0, y: 0 }),
            max: this.mapLayer.mapview.coordinatesFromWindowPoint(map, { x: 0, y: 0 })
        }

        console.log(JSON.stringify(boundaries))
    }

    /**
     * Creates the MapLayer.
     *
     * @private
     * @memberof MapApp
     */
    _setupMapLayer() {
        this.mapContainer = new PIXI.Container()
        this._mapLayer = new MapLayer(this.mapList, this.scene, this.mapContainer, {
            name: 'Root Map Layer',
            focus: this.focus,
            zoom: this.zoom,
            onChange: this._mapChanged.bind(this)
        })
    }

    setup() {
        super.setup()

        // TODO get access to fps display
        let fpsDisplay = null
        this.stage.children.forEach(element => {
            if (element.refreshFps) fpsDisplay = element
        })

        this._setupMapLayer()

        this.ui = new PIXI.Container()
        this.scene.addChild(this.ui)
        if (this.fpsLogging != null && fpsDisplay != null) this.ui.addChild(fpsDisplay)

        if (this.coordsLogging) {
            this.coordsDisplay = new CoordinateDisplay(this)
            this.ui.addChild(this.coordsDisplay)
        }

        this.__dragging = false
        this.__events = new Map()

        const scene = this.scene
        scene.interactive = true
        scene.on('pointercancel', this.__onEnd.bind(this))
        scene.on('pointerdown', this.__onStart.bind(this))
        scene.on('pointermove', this.__onMove.bind(this))
        scene.on('pointerout', this.__onEnd.bind(this))
        scene.on('pointerup', this.__onEnd.bind(this))
        scene.on('pointerupoutside', this.__onEnd.bind(this))

        return this
    }

    /**
     * You can add Dom elements directly to the app's DomLayer by calling
     * appendChild(). The elements will be forced to use an absolute positioning.
     * This shall prevent unwanted sideeffects with the app.
     *
     * @param {HTMLElement} element - Element to add to DOMRoot.
     * @memberof MapApp
     */
    appendChild(element) {
        if (!this.wrapper)
            console.error(
                `When using DOMElements on ${this.constructor.name} you must specify a wrapper in the constructor.`
            )
        if (!(element instanceof HTMLElement))
            console.error(
                'You can only append HTMLElements to DOM. If you want to add PIXI elements to the scene call app.scene.addChild(element).'
            )
        else {
            Object.assign(element.style, { position: 'absolute' })
            this.wrapper.appendChild(element)
        }
    }

    /**
     * Relayouts the app. E.g. called when the window is resized.
     *
     * @param {number} width - Desired width of the app.
     * @param {number} height - Desired height of the app.
     * @memberof MapApp
     */
    layout(width, height) {
        this.scene.resize(width, height)
        this.mapLayer.mapview.update()
        this.onSizeChanged.call(this)
    }

    /**
     * Overrides the sceneFactory of the PIXIApp to create a RigidScatterContainer instead of
     * a regular PIXI.Container()
     *
     * @private
     * @returns {RigidScatterContainer} - Returns the newly created RigidScatterContainer.
     * @memberof MapApp
     */
    sceneFactory() {
        return new RigidScatterContainer(this.width, this.height, this.renderer, {
            app: this,
            showBounds: true,
            showTouches: true,
            showPolygon: true,
            container: this
        })
    }

    /**
     * Changes the map to the given key.
     *
     * @param {string} key - Identifier of the map to change to.
     * @memberof MapApp
     */
    selectMap(key) {
        if (this.debug) console.log('Select map', key, result)
        let result = this.mapList.select(key)

        if (result && this.mapLayer) {
            this.mapLayer.changeMap(this.mapList.map)
        }
    }

    /**
     * Adds and sets a map to the mapapp.
     *
     * @param {string} key - Name of the map.
     * @param {GeoMap} map - Map to add.
     * @memberof MapApp
     */
    setMap(key, map) {
        this.addMap(key, map)
        this.selectMap(key)
    }

    /**
     * Adds a map to the maplist.
     * If no map is set, the added map will be set as default.
     *
     * @param {string} key - Identifier for the map.
     * @param {GeoMap} map - Map object to add.
     * @memberof MapApp
     */
    addMap(key, map) {
        if (this.mapList) this.mapList.add(key, map)
        else console.error('Cannot access mapLayer. It was not initialized yet.')
    }

    /**
     * Adds multiple maps at once.
     *
     * @param {object} mapObject
     * @memberof MapApp
     */
    addMaps(mapObject) {
        for (let [key, val] of Object.entries(mapObject)) {
            if (val instanceof GeoMap) {
                this.addMap(key, val)
            } else console.warn('Tried adding maps that are not og Type GeoMap.')
        }
    }

    transformed(event) {
        this.onTransform.call(this, event)
    }

    /**
     *
     * Called when the mapLayer changed the map.
     *
     * @private
     * @param {*} lastMap
     * @memberof MapApp
     */
    _mapChanged(lastMap) {
        if (lastMap) {
            lastMap.flushHandlers()
        }

        this.transformed()
        this.onMapChanged.call(this, this.map)

        this.map.onTransform.add(this.transformed.bind(this))

        if (this.ui && this.ui.parent) {
            const parent = this.ui.parent
            parent.removeChild(this.ui)
            parent.addChild(this.ui)
        }
    }

    /**
     * Returns the mapLayer of the map.
     *
     * @member {MapLayer}
     * @memberof MapApp
     */
    get mapLayer() {
        return this._mapLayer
    }

    _doesOverlayElementExist(layer, type, name) {
        let layerElements = this.overlayElements.get(layer)
        return layerElements != undefined && layerElements[type] != null && layerElements[type][name] != null
    }

    _getOverlayElement(layer, type, name) {
        let layerElements = this.overlayElements.get(layer)
        return layerElements[type][name]
    }

    _setOverlayElement(layer, type, name, value) {
        let obj = this.overlayElements.get(layer)
        if (obj == undefined) obj = {}

        if (obj[type] == null) obj[type] = {}

        obj[type][name] = value

        this.overlayElements.set(layer, obj)
    }

    /**
     * Copies the current location to the clipboard.
     *
     * @memberof MapApp
     */
    locationToClipboard() {
        let hidden = document.createElement('input')
        document.body.appendChild(hidden)
        hidden.value = '"location":' + JSON.stringify(app.mapLayer.mapview.focus)
        hidden.readOnly = true
        hidden.select()
        document.execCommand('Copy')
        this.showNotification('Copied location to clipboard.')
        document.body.removeChild(hidden)
    }

    /**
     * Can be used to copy polygons to the clipboard.
     *
     * Useful for debugging or to roughly trace a shape in the map.
     * The generated pointarray can be used as geometry of a geographic
     * or inside an overlay to draw that shape onto the map.
     *
     * @memberof MapApp
     */
    pathToClipboard() {
        let hidden = document.createElement('input')
        document.body.appendChild(hidden)

        this.drawData.push(this.mapLayer.mapview.focus)

        if (this.drawMode == this.DRAW_MODES.POLYGON_MODE) {
            let data = {
                type: 'Polygon',
                coordinates: [this.drawData]
            }

            hidden.value = '"geometry":' + JSON.stringify(data)
        } else {
            // PATH_MODE is default.
            hidden.value = JSON.stringify(this.drawData)
        }
        hidden.select()
        document.execCommand('Copy')
        this.showNotification('Location appended in clipboard.')
        document.body.removeChild(hidden)
    }

    /**
     * Returns the active map.
     *
     * @readonly
     * @memberof MapApp
     */
    get map() {
        return this.mapList.map
    }

    clearDrawData() {
        this.drawData = []
    }

    /**
     * Logs a text field on the map.
     * The text element is a DOMElement.
     *
     * @param {string} msg - Message to log.
     * @memberof MapApp
     */
    showNotification(msg) {
        let notification = document.createElement('div')
        notification.classList.add('notification')

        let text = document.createElement('p')
        text.innerHTML = msg
        notification.appendChild(text)

        /**
         * TODO: move styling (except opacity) to css.
         */
        Object.assign(notification.style, {
            opacity: 0,
            top: 0,
            left: 0,
            position: 'fixed',
            display: 'flex',
            width: '100%',
            height: '100%',
            justifyContent: 'center',
            alignItems: 'center',
            pointerEvents: 'none'
        })

        document.body.appendChild(notification)

        let popAnimation = new TimelineLite({
            onComplete: () => {
                notification.parentNode.removeChild(notification)
            }
        })
        let animationSpeed = 0.5

        popAnimation
            .to(notification, animationSpeed, {
                opacity: 1
            })
            .to(notification, animationSpeed, {
                opacity: 0
            })
    }

    /**
     * @typedef KeyCode
     * @type {object}
     * @property {string} key - an ID.
     * @property {boolean} altKey - Defines if KeyCode requires the alt key to be pressed.
     * @property {boolean} shiftKey - Defines if KeyCode requires the shift key to be pressed.
     * @property {boolean} ctrlKey - Defines if KeyCode requires the ctrl key to be pressed.
     *
     */

    /**
     * Check's if a key event matches a defined KeyCode.
     *
     * @private
     * @param {KeyboardEvent} event - Event that is fired on keydown, -pressed or -up.
     * @param {KeyCode} keyCode - KeyCode is an object in the form of : {key:number, altKey:boolean,shiftKey:boolean,ctrlKey:boolean }
     * @returns {boolean} - True, when the event matches the keycode, false otherwise.
     * @memberof MapApp
     */
    _matchKeyCode(event, keyCode) {
        // If keycode does not exist or is invalid - return.
        if (!keyCode || keyCode.key == null) return false

        let code = keyCode.key
        if (event.shiftKey) code -= 32
        const key = event.which == code || event.keyCode == code || event.charCode == code

        const ctrl = keyCode.ctrlKey == event.ctrlKey
        const shift = keyCode.shiftKey == event.shiftKey
        const alt = keyCode.altKey == event.altKey

        return key && ctrl && shift && alt
    }

    _setupKeyboardUtils() {
        document.body.addEventListener('keypress', event => {
            this._checkForKeyCode(event)
        })
    }

    /**
     * Checks on every key down if it matches a keycode.
     *
     * @private
     * @param {KeyboardEvent} event
     * @memberof MapApp
     */
    _checkForKeyCode(event) {
        if (this._matchKeyCode(event, this.keycodes.copyCoordinate)) {
            event.preventDefault()

            switch (this.drawMode) {
                case this.DRAW_MODES.PIXI_POINT:
                    this.locationToClipboard()
                    break
                case this.DRAW_MODES.PATH_MODE:
                case this.DRAW_MODES.POLYGON_MODE:
                    this.pathToClipboard()
                    break
                default:
                    console.error(
                        `Draw mode is not implemented yet: ${this.DRAW_MODES.getName(this.drawMode)}(${this.drawMode}).`
                    )
            }
        }

        if (this._matchKeyCode(event, this.keycodes.togglePathMode)) {
            if (this.drawMode == this.DRAW_MODES.PATH_MODE) {
                this.showNotification('Path Mode disabled.')
                this._resetDrawMode()
            } else {
                this.drawMode = this.DRAW_MODES.PATH_MODE
                this.showNotification('Path Mode enabled.')
                this.clearDrawData()
            }
        }

        //When SHIFT+P is pressed POLYGON-MODE is toggled:
        if (this._matchKeyCode(event, this.keycodes.togglePolygonMode)) {
            if (this.drawMode == this.DRAW_MODES.POLYGON_MODE) {
                this.showNotification('Polygon Mode disabled.')
                this._resetDrawMode()
            } else {
                this.drawMode = this.DRAW_MODES.POLYGON_MODE
                this.showNotification('Polygon Mode enabled.')
                this.clearDrawData()
            }
        }

        // When SHIFT+X is pressed toggle crosshair
        if (this.keycodes.toggleUi && this._matchKeyCode(event, this.keycodes.toggleUi)) {
            if (this.pixiUiLayer.visible) {
                this.pixiUiLayer.hide()
                this.domUiLayer.hide()
            } else {
                this.pixiUiLayer.show()
                this.domUiLayer.show()
            }
        }
    }

    _resetDrawMode() {
        this.drawMode = this.DRAW_MODES.PIXI_POINT
    }

    /**
     * @typedef KeyCodePairs
     * @type {object}
     * @property {string} name - Name of the KeyCode.
     * @property {KeyCode} keyCode - KeyCode
     *
     */

    /**
     * Extracts keycodes from a string.
     *
     * KeycodeStrings may look like this 'ctrl+shift+b'
     *
     * @private
     * @param {KeyCodePairs} nameKeyCodePairs
     * @returns {array} - Returns an array of KeyCode objects.
     * @memberof MapApp
     */
    _extractKeyCodes(nameKeyCodePairs) {
        let out = {}

        for (let [name, combinationString] of Object.entries(nameKeyCodePairs)) {
            let keys = combinationString.split('+')
            out[name] = {
                key: null,
                ctrlKey: false,
                shiftKey: false,
                altKey: false
            }
            let errors = []

            const special = ['shift', 'ctrl', 'alt']
            keys.forEach(key => {
                if (key.length == 1) {
                    if (out[name].key) {
                        const error = 'Tried to set multiple keys as keycode. This is currently not supported.'
                        errors.push(error)
                    } else out[name].key = key.charCodeAt(0)
                } else {
                    key = key.toLowerCase()
                    if (special.indexOf(key) != -1) {
                        out[name][key + 'Key'] = true
                    } else {
                        const error = 'Wrong / non-implemented special character OR typo in key: ' + key
                        errors.push(error)
                    }
                }
            })

            // Disable hotkey if an error occured.
            if (errors.length > 0)
                out[name] = {
                    key: null,
                    ctrlKey: false,
                    shiftKey: false,
                    altKey: false
                }
        }

        return out
    }

    __onStart(event) {
        this.__dragging = true

        let hittedSubmap = null
        let center = null
        for (const submap of this.submaps) {
            const radius = submap.container.width / 2
            const distance = Points.distance(submap.center, event.data.global)
            if (distance < radius) {
                hittedSubmap = submap
                center = submap.center
            }
        }

        this.__events.set(event.data.identifier, {
            event,
            submap: hittedSubmap,
            center
        })
    }

    __onMove(event) {
        if (this.__dragging) {
            const myevent = this.__events.get(event.data.identifier)

            if (myevent && myevent.submap) {
                const submap = myevent.submap
                const center = submap.center
                const radius = submap.container.width / 2
                const distance = Points.distance(center, event.data.global) / submap.scatter.scale
            }
        }
    }

    __onEnd(event) {
        this.__dragging = false
        this.__events.delete(event.data.identifier)
    }
}