MapGIS Client for JavaScript API

import FeatureRender from '../base/FeatureRender'
import FeatureCollection from '../document/layer/support/FeatureCollection'
import { defaultValue, Log } from '../util'
import { BaseRendererLayerView } from './index'
import { updateRenderer } from './support/RendererUtil'
import { Feature, FeatureSet } from '../base'
import { RendererType } from '../base/enum'
import { setElevationInfo } from '../document'

class BaseFeatureLayerView extends BaseRendererLayerView {
  _initInstance(options) {
    super._initInstance(options)
    // 渲染器
    this.render = defaultValue(options.render, new FeatureRender())
    // 要素缓存
    this._featureSetCache = new FeatureCollection()
  }

  /**
   * @description: 定义监听器
   * @return {*}
   */
  _initHandlers() {
    super._initHandlers()
    this._onFeatureChange = this._onFeatureChange.bind(this)
    this._onFeatureSetCacheChange = this._onFeatureSetCacheChange.bind(this)
    this._zoomChange = this._zoomChange.bind(this)
    // 监听要素属性变化，更新操作
    this._featureSetCache.on('set', this._onFeatureChange)
    // 监听要素变化,进行绘制或者删除操作
    this._featureSetCache.on('change', this._onFeatureSetCacheChange)
    // 监听层级变化
    this.view.on('zoom', this._zoomChange)
  }

  /**
   * @description: 移除监听器
   * @return {*}
   */
  _removeHandlers() {
    super._removeHandlers()
    this.off('set', this._onFeatureChange)
    this.off('change', this._onFeatureSetCacheChange)
    this.view.off('zoom', this._zoomChange)
  }

  /**
   * @description: renderer变化Action
   * @return {*}
   */
  _rendererChangeAction(event) {
    super._rendererChangeAction(event)
    const featureItems = this._featureSetCache.items || []
    updateRenderer(featureItems, this.layer.renderer)
  }

  /**
   * @description: 单个要素变化Action
   * @param {*} event
   * @return {*}
   */
  _onFeatureChange(event) {
    const eventPath = event.eventPath || []
    const { value } = event.eventData
    const sourceEventData = event.sourceEventData
    // 处理要素刷新机制
    if (eventPath.length <= 0 || !value) return
    if (eventPath.length > 1) {
      // 获取到要素
      const feature = value
      if (!feature) return
      const updateType = eventPath[1]
      const updateDetail = {
        geometryUpdated: null,
        symbolUpdated: null
      }
      if (updateType === 'symbol') {
        updateDetail.symbolUpdated = sourceEventData
      } else if (updateType === 'geometry') {
        updateDetail.geometryUpdated = sourceEventData
      }
      this.render.updateFeature(this.innerLayer, [feature], [updateDetail])
    }
  }

  /**
   * @description: 要素数据集更新
   * @param {*} e
   * @return {*}
   */
  _onFeatureSetCacheChange(e) {
    if (e) {
      if (e.added) {
        this.render.drawFeature(this.innerLayer, e.added)
      }
      if (e.removed) {
        this.render.clearFeature(this.innerLayer, e.removed)
      }
    }
  }

  /**
   * @description: 层级变化
   * @param {*}
   * @return {*}
   */
  _zoomChange(e) {
    if (this.layer && this.layer.renderer) {
      const renderer = this.layer.renderer
      // 根据层级实时变化
      if (renderer.type === RendererType.random) {
        const featureItems = this._featureSetCache.items || []
        updateRenderer(featureItems, renderer)
      }
    }
  }

  /**
   * @description: 初始化要素
   * @param {*} featureSet
   * @param {*} renderer
   * @return {*}
   */
  _initFeatures(featureSet, renderer) {
    let features = []
    if (featureSet instanceof FeatureSet) {
      features = featureSet.features
    } else if (
      Array.isArray(featureSet) &&
      featureSet.every((feature) => feature instanceof Feature)
    ) {
      features = featureSet
    } else {
      Log.info('传入要素集错误')
    }
    // 如果要素上没有高程参数，就用图层上的，否则用要素自己的
    for (let i = 0; i < features.length; i++) {
      setElevationInfo(features[i], this.layer)
    }
    // 设置renderer信息
    updateRenderer(features, renderer)
    // 添加要素
    this._featureSetCache.addMany(features)
  }

  /**
   * 移除图层视图
   * @param {LayerEvent} 图层事件
   * @return {Promise<LayerView>} 图层视图
   */
  onRemove(event) {
    this._featureSetCache.removeAll()
    super.onRemove(event)
  }
}

export default BaseFeatureLayerView