import { MathUtils } from 'three'
import Camera from '../Components/Camera'
import { normLng } from '../Components/utils'
import { controls } from '../config.json'

import { CameraPosition } from '../Types'

enum TouchType { Touch, Zoom }

export default class Controls{

    camera: Camera
    canvas: HTMLCanvasElement
    tween: boolean

    fovMax: number
    fovMin: number

    isInteracting: boolean

    onTouchDist: number
    onTouchFov: number
    touchType: TouchType

    onMouseDownMouseX: number
    onMouseDownMouseY: number

    lng: number
    lngVector: number
    onMouseDownLng: number

    lat: number
    latVector: number
    onMouseDownLat: number

    fov: number
    fovVector: number

    phi: number
    theta: number

    onTouchStartHandler: any
    onClickHandler: any
    onMouseDownHandler: any
    onMouseWheelHandler: any
    onTouchMoveHandler: any
    onTouchUpHandler: any
    onMouseMoveHandler: any
    onMouseUpHandler: any

    constructor(camera: Camera, canvas: HTMLCanvasElement) {

        this.camera = camera;
        this.canvas = canvas
        this.tween = true
        this.fovMax = controls.fovMax;
        this.fovMin = controls.fovMin;

        this.isInteracting = false
        this.onMouseDownMouseX = 0
        this.onMouseDownMouseY = 0

        this.lng = 90
        this.lngVector = 90
        this.onMouseDownLng = 0

        this.lat = 0
        this.latVector = 0
        this.onMouseDownLat = 0
        this.phi = 0
        this.theta = 0

        this.fov = 70
        this.fovVector = 70

        this.init()
    }

    init(){

        this.onTouchStartHandler = this.onTouchStart.bind(this)
        this.onClickHandler = this.onClick.bind(this)
        this.onMouseDownHandler = this.onMouseDown.bind(this)
        this.onMouseWheelHandler = this.onMouseWheel.bind(this)

        this.canvas.addEventListener('touchstart', this.onTouchStartHandler)
        this.canvas.addEventListener( 'click', this.onClickHandler )
        this.canvas.addEventListener( 'mousedown', this.onMouseDownHandler )
        this.canvas.addEventListener( 'mousewheel', this.onMouseWheelHandler )

        this.camera.lookAt(this.lat, this.lng)
    }

    setTween(tween: boolean){
        this.tween = tween
    }

    position(): CameraPosition{
        return { lat: this.lat, lng: normLng(this.lng), fov: this.fov }
    }

    tick(delta: number) {

        if ( this.isInteracting === false ) {
            //lng += 0.025;
        }

        this.lat = Math.max( - 90, Math.min( 89.9999999999, this.lat ) );
        if(this.tween){
            if(this.fovVector != this.fov){
                let diff = (this.fov - this.fovVector) / 10
                if(Math.abs(this.fovVector / diff) > 500000){
                    this.fov = this.fovVector
                }else{
                    this.fov = this.fov - diff
                }
                this.onFovChanged()
            }

            let posChanged = false

            if(this.latVector != this.lat){
                let diff = (this.lat - this.latVector) / 10
                if(Math.abs(this.fov / diff) > 100000){
                    this.lat = this.latVector
                }else{
                    this.lat = this.lat - diff
                }
                posChanged = true
            }

            if(this.lngVector != this.lng){
                let diff = (this.lng - this.lngVector) / 10
                if(Math.abs(this.fov / diff) > 100000){
                    this.lng = this.lngVector
                }else{
                    this.lng = this.lng - diff
                }
                posChanged = true
            }

            if(posChanged) this.onPosChanged();

        }
    }

    // Touch events

    onTouchStart(e: TouchEvent){

        var touches = e.touches
        if(touches.length == 1){
            this.touchType = TouchType.Touch
        }else if(touches.length == 2){
            this.touchType = TouchType.Zoom
        }

        if(this.touchType == TouchType.Touch && e.type == 'touchstart'){
            var touch = touches[0]
            this.isInteracting = true
            this.onMouseDownMouseX = touch.pageX
            this.onMouseDownMouseY = touch.pageY
            this.onMouseDownLng = this.lng
            this.onMouseDownLat = this.lat
        }

        if(this.touchType == TouchType.Zoom){
            this.onTouchDist = Math.hypot(
                touches[0].pageX - touches[1].pageX,
                touches[0].pageY - touches[1].pageY
            )
            this.onTouchFov = this.fov
        }

        this.onTouchMoveHandler = this.onTouchMove.bind(this)
        this.onTouchUpHandler = this.onTouchUp.bind(this)

        this.canvas.addEventListener( 'touchmove', this.onTouchMoveHandler )
        this.canvas.addEventListener( 'touchend', this.onTouchUpHandler )
        this.canvas.addEventListener( 'touchcancel', this.onTouchUpHandler )
        e.preventDefault()
    }

    onTouchMove(e: TouchEvent){

        var touches = e.touches
        var newTouchType: TouchType
        if(touches.length == 1){
            newTouchType = TouchType.Touch
        }else if(touches.length == 2){
            newTouchType = TouchType.Zoom
        }
        if(this.touchType != newTouchType){
            return null
        }

        if(this.touchType == TouchType.Touch && e.type == 'touchmove'){
            var touch = touches[0]
            this.lng = ( this.onMouseDownMouseX - touch.pageX ) * this.camera.get().fov * controls.moveFactor / this.canvas.clientWidth + this.onMouseDownLng;
            this.lat = ( touch.pageY - this.onMouseDownMouseY ) * this.camera.get().fov * controls.moveFactor / this.canvas.clientWidth + this.onMouseDownLat;
            this.latVector = this.lat
            this.lngVector = this.lng
            this.onPosChanged()
        }

        if(this.touchType == TouchType.Zoom && e.type == 'touchmove'){
            var dist = Math.hypot(
                touches[0].pageX - touches[1].pageX,
                touches[0].pageY - touches[1].pageY
            )
            var diff = this.onTouchDist - dist
            this.fov = MathUtils.clamp( this.onTouchFov + diff * this.onTouchFov / 500, this.fovMin, this.fovMax )
            this.fovVector = this.fov
            this.onFovChanged()
        }

    }

    onTouchUp(e: TouchEvent){
        this.isInteracting = false
        this.canvas.removeEventListener( 'touchmove', this.onTouchMoveHandler )
        this.canvas.removeEventListener( 'touchend', this.onTouchUpHandler )
        this.canvas.removeEventListener( 'touchcancel', this.onTouchMoveHandler )
        this.touchType = null

        if(e.changedTouches.length == 1){
            const touch = e.changedTouches[0]
            if(touch.clientX == this.onMouseDownMouseX && touch.clientY == this.onMouseDownMouseY){
                this.onTap(e)
            }
        }
    }

    onTap(e: TouchEvent){
        console.log('onTap')
    }

    // mouse events

    onMouseDown(e: MouseEvent){
        this.isInteracting = true
        this.onMouseDownMouseX = e.clientX
        this.onMouseDownMouseY = e.clientY
        this.onMouseDownLng = this.lng
        this.onMouseDownLat = this.lat

        this.onMouseMoveHandler = this.onMouseMove.bind(this)
        this.onMouseUpHandler = this.onMouseUp.bind(this)

        this.canvas.addEventListener( 'mousemove', this.onMouseMoveHandler )
        this.canvas.addEventListener( 'mouseup', this.onMouseUpHandler )
        this.canvas.addEventListener( 'mouseleave', this.onMouseUpHandler )
    }
    
    onMouseMove(e: MouseEvent){
        if(this.tween){
            this.lngVector = ( this.onMouseDownMouseX - e.clientX ) * this.camera.get().fov * controls.moveFactor / this.canvas.clientWidth + this.onMouseDownLng
            this.latVector = ( e.clientY - this.onMouseDownMouseY ) * this.camera.get().fov * controls.moveFactor / this.canvas.clientWidth + this.onMouseDownLat
        }else{
            this.lng = ( this.onMouseDownMouseX - e.clientX ) * this.camera.get().fov * controls.moveFactor / this.canvas.clientWidth + this.onMouseDownLng;
            this.lat = ( e.clientY - this.onMouseDownMouseY ) * this.camera.get().fov * controls.moveFactor / this.canvas.clientWidth + this.onMouseDownLat;
            this.onPosChanged()
        }
    }
    
    onMouseUp(e: MouseEvent){
        this.isInteracting = false
         this.canvas.removeEventListener( 'mousemove', this.onMouseMoveHandler )
         this.canvas.removeEventListener( 'mouseup', this.onMouseUpHandler )
         this.canvas.removeEventListener( 'mouseleave', this.onMouseUpHandler )
    }

    onMouseWheel(e: WheelEvent){
        e.preventDefault()
        e.stopPropagation()
        if(this.tween){
            this.fovVector = MathUtils.clamp(this.fovVector + e.deltaY * this.fovVector / 1000, this.fovMin, this.fovMax )
        }else{
            this.fov = MathUtils.clamp( this.fov + e.deltaY * this.fov / 1000, this.fovMin, this.fovMax )
            this.onFovChanged()
        }
    }

    onClick(e: PointerEvent){
        if(e.clientX == this.onMouseDownMouseX && e.clientY == this.onMouseDownMouseY){
            this.canvas.dispatchEvent(new CustomEvent('panoClick', {detail: e}))
        }
    }

    onFovChanged(){
        this.camera.setFov(this.fov)
        this.canvas.dispatchEvent( new CustomEvent('fovChanged', {detail: { fov: this.fov }}) )
    }

    onPosChanged(){
        this.camera.lookAt(this.lat, this.lng)
        this.canvas.dispatchEvent(new CustomEvent('cameraMove', {detail: { lat: this.lat, lng: this.lng }}))
    }
}