//二、折线
// DrawPolyline
/*
绘制线
 */
class DrawPolyline {
    constructor(arg) {
        this.viewer = arg.viewer;
        this.Cesium = arg.Cesium;
        // this.callback=arg.callback;
        this._polyline = null; //活动线
        this._polylineLast = null; //最后一条线
        this._positions = [];  //活动点
        this._entities_point = [];  //脏数据
        this._entities_line = [];  //脏数据
        this._polylineData = null; //用于构造线数据
        this.DrawStartEvent = new Cesium.Event(); //开始绘制事件
        this.DrawEndEvent = new Cesium.Event(); //结束绘制事件 
		
		/* 通用参数集合 */
		this._param = {
			id: "DrawStraightArrow",
			polygonColor: 'rgba(0,255,0,0.5)', //面填充颜色
			outlineColor: 'rgba(255, 255, 255, 1)', //边框颜色
			outlineWidth: 1, //边框宽度
		}
		
		/* 创建面材质 */
		this.polygonMaterial = Cesium.Color.fromCssColorString(this._param.polygonColor);
		/* 创建线材质 */
		// this.outlineMaterial = new Cesium.PolylineDashMaterialProperty({//曲线
		// 	dashLength: 16,
		// 	color: Cesium.Color.fromCssColorString(this._param.outlineColor)
		// });
		this.outlineMaterial = Cesium.Color.fromCssColorString(this._param.outlineColor);
    }
 
    //返回最后活动线
    get line() {
        return this._polylineLast;
    }
 
    //返回线数据用于加载线
    getData() {
        return this._polylineData;
    }

    // 修改编辑调用计算
    computePosition(data){
        //计算面
        let $this = this
        var lnglatArr = [];
        for (var i = 0; i < data.length; i++) {
            var lnglat = $this.cartesianToLatlng(data[i]);
            lnglatArr.push(lnglat)
        }
        $this._polylineData = lnglatArr;
        return data;
    }
 
    //加载线
    addload(data) {
        var $this = this;
        var lnglatArr = [];
        for (var i = 0; i < data.length; i++) {
            var lnglat = $this.LatlngTocartesian(data[i]);
            lnglatArr.push(lnglat)
        }
        var polyline = this.viewer.entities.add({
            Type:'DrawPolyline',
            Position:data,
            id:data.id || $this.objId,
            polyline: {
                positions: lnglatArr,
                show: true,
                material: $this.Cesium.Color.RED,
                width: 3,
                clampToGround: true
            }
        });
        return polyline;
    }
 
    //开始创建
    startCreate(drawType) {
        this.drawType = drawType;
        var $this = this;
        this.handler = new this.Cesium.ScreenSpaceEventHandler(this.viewer.scene.canvas);
        this.handler.setInputAction(function (evt) { //单机开始绘制
            //屏幕坐标转地形上坐标
            var cartesian = $this.getCatesian3FromPX(evt.position);
            if ($this._positions.length == 0) {
                $this._positions.push(cartesian.clone());
            }
            $this._positions.push(cartesian);
            $this.createPoint(cartesian);// 绘制点
        }, $this.Cesium.ScreenSpaceEventType.LEFT_CLICK);
        this.handler.setInputAction(function (evt) { //移动时绘制线
            if ($this._positions.length < 1) return;
            var cartesian = $this.getCatesian3FromPX(evt.endPosition);
            if (!$this.Cesium.defined($this._polyline)) {
                $this._polyline = $this.createPolyline();
            }
            if ($this._polyline) {
                $this._positions.pop();
                $this._positions.push(cartesian);
            }
        }, $this.Cesium.ScreenSpaceEventType.MOUSE_MOVE);
        this.handler.setInputAction(function (evt) {
            if (!$this._polyline) return;
            var cartesian = $this.getCatesian3FromPX(evt.position);
            $this._positions.pop();
            // $this._positions.push(cartesian);
            $this.createPoint(cartesian);// 绘制点
            $this._polylineData = $this._positions.concat();
            $this.viewer.entities.remove($this._polyline); //移除
            $this._polyline = null;
            $this._positions = [];
            var lnglatArr = [];
            for (var i = 0; i < $this._polylineData.length; i++) {
                var lnglat = $this.cartesianToLatlng($this._polylineData[i]);
                lnglatArr.push(lnglat)
            }
            $this._polylineData = lnglatArr;
            var line = $this.addload($this._polylineData); //加载线
            $this._entities_line.push(line);
            $this._polylineLast=line;
            // if(typeof $this.callback=="function"){
            //     $this.callback(line);
            // }
            $this.clearPoint();
            $this.destroy()
        }, $this.Cesium.ScreenSpaceEventType.RIGHT_CLICK);
    }
 
    //创建点
    createPoint(cartesian) {
        var $this = this;
        var point = this.viewer.entities.add({
            position: cartesian,
            point: {
                pixelSize: 10,
                color: $this.Cesium.Color.RED,
                heightReference: Cesium.HeightReference.CLAMP_TO_GROUND,
            }
        });
        $this._entities_point.push(point);
        return point;
    }
 
    //创建线
    createPolyline() {
        var $this = this;
        var polyline = this.viewer.entities.add({
            polyline: {
                //使用cesium的peoperty
                positions: new $this.Cesium.CallbackProperty(function () {
                    return $this._positions
                }, false),
                show: true,
                material: $this.Cesium.Color.RED,
                width: 3,
                clampToGround: true
            }
        });
        $this._entities_line.push(polyline);
        return polyline;
    }

    cartesianToLatlng(cartesian) {
        var latlng = this.viewer.scene.globe.ellipsoid.cartesianToCartographic(cartesian);
        var lat = this.Cesium.Math.toDegrees(latlng.latitude);
        var lng = this.Cesium.Math.toDegrees(latlng.longitude);
        return [lng, lat];
    }

    LatlngTocartesian(latlng) {
        let cartesian3 = this.Cesium.Cartesian3.fromDegrees(latlng[0], latlng[1]);
        return cartesian3
    }

    clearPoint() {
        this.DrawEndEvent.raiseEvent(this._polylineLast , this._polylineData, this.drawType);
        for (var i = 0; i < this._entities_point.length; i++) {
            this.viewer.entities.remove(this._entities_point[i]);
        }
        this._entities_point = [];  //脏数据
    }
 
    //销毁
    destroy() {
        if (this.handler) {
            this.handler.destroy();
            this.handler = null;
        }
    }
 
    //清空实体对象
    clear() {
        for (var i = 0; i < this._entities_point.length; i++) {
            this.viewer.entities.remove(this._entities_point[i]);
        }
        for (var i = 0; i < this._entities_line.length; i++) {
            this.viewer.entities.remove(this._entities_line[i]);
        }
        this._polyline = null;
        this._positions = [];
        this._entities_point = [];  //脏数据
        this._entities_line = [];  //脏数据
        this._polylineData = null; //用于构造线数据
        this._polylineLast=null;
    }
 
    getCatesian3FromPX(px) {
        var cartesian;
        var ray = this.viewer.camera.getPickRay(px);
        if (!ray) return null;
        cartesian = this.viewer.scene.globe.pick(ray, this.viewer.scene);
        return cartesian;
    }
}
 
export default DrawPolyline