import * as Cesium from 'cesium'
import { MapTooltip } from '@ztzf/utils'
import { ToolBase } from '../ToolBase'
import { getBoundsFromCartesians, rectanglePositionsFromBounds } from '../shapeUtils'

const DEFAULT_STYLE = {
	fill: Cesium.Color.fromBytes(45, 140, 240, 99),
	outline: Cesium.Color.fromBytes(45, 140, 240, 255),
}
const resolveStyle = style => ({
	fill: style?.fill || DEFAULT_STYLE.fill,
	outline: style?.outline || DEFAULT_STYLE.outline,
})

export class DrawRectangleTool extends ToolBase {
	constructor(viewer, options = {}) {
		super(viewer)
		this.tooltip = new MapTooltip(viewer)
		this.dataSource = null
		this.rectangleEntity = null
		this.outlineEntity = null
		this.startPosition = null
		this.endPosition = null
		this.isDrawing = false
		this.style = resolveStyle(options?.style)
	}

	start() {
		this.dataSource = new Cesium.CustomDataSource('draw-rectangle')
		this.viewer.dataSources.add(this.dataSource)
		this.handler = new Cesium.ScreenSpaceEventHandler(this.viewer.scene.canvas)

		this.handler.setInputAction(click => this.handleLeftClick(click), Cesium.ScreenSpaceEventType.LEFT_CLICK)
		this.handler.setInputAction(movement => this.handleMouseMove(movement), Cesium.ScreenSpaceEventType.MOUSE_MOVE)

		this.tooltip.hide()
	}

	handleLeftClick(click) {
		const position = this.getPositionFromScreen(click.position)
		if (!position) return

		if (!this.startPosition) {
			this.startPosition = position
			this.endPosition = position
			this.isDrawing = true
			this.createEntities()
			this.tooltip.show('单击结束绘制', click.position)
			return
		}

		if (this.isDrawing) {
			this.endPosition = position
			this.isDrawing = false
			const positions = this.getRectanglePositions()
			this.notify('getPolygonPositions', positions)
			this.tooltip.hide()
			this.clearPreviewEntities()
		}
	}

	handleMouseMove(movement) {
		const tipText = this.startPosition ? '单击结束绘制' : '单击设置起点'
		if (!this.tooltip?.isVisible) {
			this.tooltip.show(tipText, movement.endPosition)
		} else {
			this.tooltip.show(tipText)
			this.tooltip.move(movement.endPosition)
		}
		if (!this.isDrawing) return
		const position = this.getPositionFromScreen(movement.endPosition)
		if (!position) return
		this.endPosition = position
	}

	createEntities() {
		if (this.rectangleEntity) return
		const hierarchy = new Cesium.CallbackProperty(() => {
			const positions = this.getRectanglePositions()
			return new Cesium.PolygonHierarchy(positions)
		}, false)

		this.rectangleEntity = this.dataSource.entities.add({
			polygon: {
				hierarchy,
				material: this.style.fill,
				outline: false,
				heightReference: Cesium.HeightReference.CLAMP_TO_GROUND,
			},
		})

		this.outlineEntity = this.dataSource.entities.add({
			polyline: {
				positions: new Cesium.CallbackProperty(() => {
					const positions = this.getRectanglePositions()
					return positions.length ? [...positions, positions[0]] : []
				}, false),
				clampToGround: true,
				width: 2,
				material: this.style.outline,
			},
		})
	}

	getRectanglePositions() {
		if (!this.startPosition || !this.endPosition) return []
		const bounds = getBoundsFromCartesians([this.startPosition, this.endPosition])
		return rectanglePositionsFromBounds(bounds)
	}

	clearPreviewEntities() {
		if (!this.dataSource) return
		this.dataSource.entities.removeAll()
		this.rectangleEntity = null
		this.outlineEntity = null
	}

	getPositionFromScreen(screenPosition) {
		const scene = this.viewer.scene
		const ray = scene.camera.getPickRay(screenPosition)
		const cartesian = ray ? scene.globe.pick(ray, scene) : null
		if (cartesian) return cartesian
		return scene.camera.pickEllipsoid(screenPosition, scene.globe.ellipsoid)
	}

	setStyle(style) {
		this.style = resolveStyle(style)
		if (this.rectangleEntity?.polygon) {
			this.rectangleEntity.polygon.material = this.style.fill
		}
		if (this.outlineEntity?.polyline) {
			this.outlineEntity.polyline.material = this.style.outline
		}
	}

	destroy() {
		if (this.dataSource) {
			this.dataSource.entities.removeAll()
			this.viewer.dataSources.remove(this.dataSource)
			this.dataSource = null
		}
		if (this.handler) {
			this.handler.removeInputAction(Cesium.ScreenSpaceEventType.LEFT_CLICK)
			this.handler.removeInputAction(Cesium.ScreenSpaceEventType.MOUSE_MOVE)
			this.handler.destroy()
			this.handler = null
		}
		this.tooltip?.destroy()
		this.tooltip = null
		this.startPosition = null
		this.endPosition = null
		this.isDrawing = false
	}
}