/**
 * 接口请求缓存
 * 1、urlPath变换，清空缓存
 * 2、参数变化重新请求
 */

interface IDelStoreItem {
  paramsJson?: string,
  data?: any,
  callbackList: Function[]
}

interface ICacheReq {
  delStoreFc: Function[],
  delStore: Function,
  reg: Function
}

const cacheReq: ICacheReq = {
  // 重制缓存Fc列表
  delStoreFc: [],
  // 清空缓存列表
  delStore() {
    this.delStoreFc.forEach(item => item())
  },
  // 注册
  reg(Fc) {
    let cacheList: IDelStoreItem[] = [] // 缓存数据
    this.delStoreFc.push(() => {
      cacheList = []
    })
    return (callback: any = null, params = {}, cache = true) => {
      return new Promise((resolve: Function) => {
        if (callback) resolve()
        else callback = resolve
        const crtParamsJson = JSON.stringify(params)
        // 查找缓存列表
        let find: any = cache && cacheList.find(item => {
          return item.paramsJson === crtParamsJson
        })
        if (find?.data) {
          return callback(find.data)
        } else if (!find) {
          cacheList.push({
            paramsJson: crtParamsJson,
            data: null,
            callbackList: [callback]
          })
          find = cacheList[cacheList.length - 1]
        } else {
          find.callbackList.push(callback)
        }
        if (find.callbackList.length > 1) return
        Fc((data) => {
          find.data = data
          find.callbackList.forEach(back => {
            back(data)
          })
          find.callbackList = []
        }, params)
      })
    }
  }
}

export default cacheReq