// DrawSector
/*
九、绘制扇形
 */
class DrawSector {
    constructor(arg) {
        this.viewer = arg.viewer;
        this.Cesium = arg.Cesium;
        this.floatingPoint = null;//标识点
        this._sector = null; //活动扇形
        this._sectorLast = null; //最后一个扇形
        this._positions = [];  //活动点
        this._entities_point = [];  //脏数据
        this._entities_sector = [];  //脏数据
        this._sectorData = null; //用于构造扇形数据
        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);
    }

    //返回扇形
    get sector() {
        return this._sectorLast;
    }

    //返回扇形数据用于加载扇形
    getData() {
        return this._sectorData;
    }

    // 修改编辑调用计算
    computePosition(data){
        let $this = this;
        let pnts = data;
        let center = $this.lonLatToMercator($this.cartesianToLatlng(pnts[0]));
        let pnt2 = $this.lonLatToMercator($this.cartesianToLatlng(pnts[1]));
        let pnt3 = $this.lonLatToMercator($this.cartesianToLatlng(pnts[2]));
        var radius = $this.MathDistance(pnt2, center);
        var startAngle = $this.getAzimuth(pnt2, center);
        var endAngle = $this.getAzimuth(pnt3, center);
        var pList = $this.getArcPoints(center, radius, startAngle, endAngle);
        pList.push(pnts[0], pList[0]);
        let arrow = [];
        for (var i = 0; i < pList.length; i++) {
            var cart3 = new $this.Cesium.Cartesian3(pList[i].x, pList[i].y, pList[i].z);
            arrow.push(cart3);
        }
        var lnglatArr = [];
        for (var d = 0; d < data.length; d++){
            lnglatArr.push($this.cartesianToLatlng(data[d]))
        }
        $this._sectorData = lnglatArr;
        return new $this.Cesium.PolygonHierarchy(arrow)
    }

    //加载扇形
    addload(data) {
        var $this = this;
        let pnts = data;
        let center = $this.lonLatToMercator(pnts[0]);
        let pnt2 = $this.lonLatToMercator(pnts[1]);
        let pnt3 = $this.lonLatToMercator(pnts[2]);
        var radius = $this.MathDistance(pnt2, center);
        var startAngle = $this.getAzimuth(pnt2, center);
        var endAngle = $this.getAzimuth(pnt3, center);
        var pList = $this.getArcPoints(center, radius, startAngle, endAngle);
        let pntsc = $this.Cesium.Cartesian3.fromDegrees(pnts[0][0], pnts[0][1])
        pList.push(pntsc, pList[0]);
        let arrow = [];
        for (var i = 0; i < pList.length; i++) {
            var cart3 = new $this.Cesium.Cartesian3(pList[i].x, pList[i].y, pList[i].z);
            arrow.push(cart3);
        }
        var arrowEntity = $this.viewer.entities.add({
            Type: 'DrawSector',
            Position: data,
            id: data.id || $this.objId,
            polygon: {
                hierarchy: new $this.Cesium.PolygonHierarchy(arrow),
                show: true,
                fill: true,
                clampToGround: true,
                material: $this.Cesium.Color.AQUA.withAlpha(0.9)
            }
        });
        return arrowEntity;
    }

    //开始创建
    startCreate() {
        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 == 3) return
            if ($this._positions.length < 3) {
                $this.floatingPoint = $this.createPoint(cartesian);
                $this._positions.push(cartesian);
            }
            if (!$this._sector) {
                // $this.createPoint(cartesian);// 绘制点
            }


        }, $this.Cesium.ScreenSpaceEventType.LEFT_CLICK);
        this.handler.setInputAction(function (evt) { //移动时绘制面
            if ($this._positions.length < 2) return;
            var cartesian = $this.getCatesian3FromPX(evt.endPosition);
            if ($this._positions.length == 2) {
                $this._positions.push(cartesian);
            }
            if ($this._positions.length == 3) {
                $this._positions.pop();
                $this._positions.push(cartesian);
                if (!$this.Cesium.defined($this._sector)) {
                    $this._sector = $this.createsector();
                }
            }

        }, $this.Cesium.ScreenSpaceEventType.MOUSE_MOVE);

        this.handler.setInputAction(function (evt) {
            if (!$this._sector) return;
            var cartesian = $this.getCatesian3FromPX(evt.position);
            $this._positions.pop();
            $this._positions.push(cartesian);
            $this._sectorData = $this._positions.concat();
            $this.viewer.entities.remove($this._sector); //移除
            $this._sector = null;
            $this._positions = [];
            $this.floatingPoint.position.setValue(cartesian);
            var lnglatArr = [];
            for (var i = 0; i < $this._sectorData.length; i++) {
                var lnglat = $this.cartesianToLatlng($this._sectorData[i]);
                lnglatArr.push(lnglat)
            }
            $this._sectorData = lnglatArr;
            var sector = $this.addload(lnglatArr); //加载
            $this._entities_sector.push(sector);
            $this._sectorLast = sector;
            $this.clearPoint();
            $this.destroy()
        }, $this.Cesium.ScreenSpaceEventType.RIGHT_CLICK);
    }

    //创建直线扇形
    createsector() {
        // console.log(this._positions)
        var $this = this;
        var arrowEntity = $this.viewer.entities.add({
            polygon: {
                hierarchy: new $this.Cesium.CallbackProperty(
                    function () {
                        // if(this._positions.length < 3) return
                        let pnts = $this._positions;
                        let center = $this.lonLatToMercator($this.cartesianToLatlng(pnts[0]));
                        let pnt2 = $this.lonLatToMercator($this.cartesianToLatlng(pnts[1]));
                        let pnt3 = $this.lonLatToMercator($this.cartesianToLatlng(pnts[2]));
                        var radius = $this.MathDistance(pnt2, center);
                        var startAngle = $this.getAzimuth(pnt2, center);
                        var endAngle = $this.getAzimuth(pnt3, center);
                        var pList = $this.getArcPoints(center, radius, startAngle, endAngle);
                        pList.push(pnts[0], pList[0]);
                        let arrow = [];
                        for (var i = 0; i < pList.length; i++) {
                            var cart3 = new $this.Cesium.Cartesian3(pList[i].x, pList[i].y, pList[i].z);
                            arrow.push(cart3);
                        }

                        return new $this.Cesium.PolygonHierarchy(pList);

                    }, false),
                show: true,
                fill: true,
                clampToGround: true,
                material: $this.Cesium.Color.AQUA.withAlpha(0.5)
            }
        }
        )
        $this._entities_sector.push(arrowEntity);
        return arrowEntity
    }

    //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;
    }

    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];
    }
    /**
     * 经纬度坐标转墨卡托坐标
     */
    // 墨卡托坐标系：展开地球，赤道作为x轴，向东为x轴正方，本初子午线作为y轴，向北为y轴正方向。
    // 数字20037508.34是地球赤道周长的一半：地球半径6378137米，赤道周长2*PI*r = 2 * 20037508.3427892，墨卡托坐标x轴区间[-20037508.3427892,20037508.3427892]
    lonLatToMercator(Latlng) {
        var E = Latlng[0];
        var N = Latlng[1];
        var x = E * 20037508.34 / 180;
        var y = Math.log(Math.tan((90 + N) * Math.PI / 360)) / (Math.PI / 180);
        y = y * 20037508.34 / 180;
        return [x, y]
    }

    WebMercator2lonLat(mercator) {
        let x = mercator[0] / 20037508.34 * 180;
        let ly = mercator[1] / 20037508.34 * 180;
        let y = 180 / Math.PI * (2 * Math.atan(Math.exp(ly * Math.PI / 180)) - Math.PI / 2)
        return [x, y];
    }

    //销毁
    destroy() {
        if (this.handler) {
            this.handler.destroy();
            this.handler = null;
        }
    }

    clearPoint() {
        this.DrawEndEvent.raiseEvent(this._sectorLast, this._sectorData);
        for (var i = 0; i < this._entities_point.length; i++) {
            this.viewer.entities.remove(this._entities_point[i]);
        }
        this._entities_point = [];  //脏数据
    }

    //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_sector.length; i++) {
            this.viewer.entities.remove(this._entities_sector[i]);
        }
        this.floatingPoint = null;//标识点
        this._sector = null; //活动扇形
        this._sectorLast = null; //最后一个扇形
        this._positions = [];  //活动点
        this._entities_point = [];  //脏数据
        this._entities_sector = [];  //脏数据
        this._sectorData = null; //用于构造扇形数据
    }

    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;
    }

    // 求取扇形坐标函数/
    //扇形配置函数
    MathDistance(pnt1, pnt2) {
        return Math.sqrt(Math.pow(pnt1[0] - pnt2[0], 2) + Math.pow(pnt1[1] - pnt2[1], 2));
    }

    getAzimuth(startPoint, endPoint) {
        var azimuth;
        var angle = Math.asin(Math.abs(endPoint[1] - startPoint[1]) / this.MathDistance(startPoint, endPoint));

        if (endPoint[1] >= startPoint[1] && endPoint[0] >= startPoint[0]) {
            azimuth = angle + Math.PI;
        } else if (endPoint[1] >= startPoint[1] && endPoint[0] < startPoint[0]) {
            azimuth = Math.PI * 2 - angle;
        } else if (endPoint[1] < startPoint[1] && endPoint[0] < startPoint[0]) {
            azimuth = angle;
        } else if (endPoint[1] < startPoint[1] && endPoint[0] >= startPoint[0]) {
            azimuth = Math.PI - angle;
        }

        return azimuth;
    }


    getArcPoints(center, radius, startAngle, endAngle) {
        var x = null,
            y = null,
            z = null,
            pnts = [],
            angleDiff = endAngle - startAngle;
        angleDiff = angleDiff < 0 ? angleDiff + Math.PI * 2 : angleDiff;

        for (var i = 0; i <= 100; i++) {
            var angle = startAngle + angleDiff * i / 100;
            x = center[0] + radius * Math.cos(angle);
            y = center[1] + radius * Math.sin(angle);
            let latlon = this.WebMercator2lonLat([x, y])
            pnts.push(this.Cesium.Cartesian3.fromDegrees(latlon[0], latlon[1]));
        }
        return pnts;
    }
}

export default DrawSector