import { DataSource, DataSourceStaticFunction, DataSourceDb, DataSourceServer, DataSourceProcessFunction } from './YvanDataSource'
import { YvEvent, YvEventDispatch } from './YvanEvent'
import * as YvanUI from './YvanUIExtend'
import { brokerInvoke } from './Service'
import { Db } from './YvanUIDb'
import _ from 'lodash'

export class YvDataSource<T> {
  private readonly module: any
  private option: DataSource<T>
  private dataSourceProcess?: DataSourceProcessFunction
  private ctl: any
  private watches: Function[] = []
  public reload: undefined | (() => void)

  customFunctionModeDebounce = _.debounce((option: DataSourceStaticFunction<T>) => {
    const that = this

    that.ctl.loading = true
    option.call(that.module, that.ctl, {
      successCallback(data: any[]) {
        if (that.dataSourceProcess) {
          //自定义的数据处理过程
          that.ctl.dataReal = that.dataSourceProcess(data)
        } else {
          that.ctl.dataReal = data
        }

        that.ctl.loading = false
        YvEventDispatch(that.ctl.onDataComplete, that.ctl, undefined)

      },
      failCallback() {
        that.ctl.dataReal = []
        that.ctl.loading = false
        YvEventDispatch(that.ctl.onDataComplete, that.ctl, undefined)
      }
    })
  });

  sqlModeDebounce = _.debounce((option: DataSourceDb<T> | DataSourceServer<T>) => {
    const that = this

    let ajaxPromise: Promise<Db.Response>;
    if (option.type === 'SQL') {
      const ajaxParam = {
        params: option.params,
        needCount: false,
        sqlId: option.sqlId
      }
      const allow = YvEventDispatch(option.onBefore, that.ctl, ajaxParam)
      if (allow === false) {
        // 不允许请求
        return;
      }
      ajaxPromise = YvanUI.dbs[option.db].query(ajaxParam)

    } else if (option.type === 'Server') {
      const [serverUrl, method] = _.split(option.method, '@');
      const ajaxParam = {
        params: option.params,
        needCount: false,
      }
      const allow = YvEventDispatch(option.onBefore, that.ctl, ajaxParam)
      if (allow === false) {
        // 不允许请求
        return;
      }
      ajaxPromise = <Promise<Db.Response>>brokerInvoke(YvanUI.getServerPrefix(serverUrl), method, ajaxParam)

    } else {
      console.error('unSupport dataSource mode:', option);
      that.ctl.dataReal = []
      that.ctl.loading = false
      return;
    }

    //异步请求数据内容
    that.ctl.loading = true
    ajaxPromise.then(res => {
      YvEventDispatch(option.onAfter, that.ctl, res)
      const { data: resultData, params: resParams } = res

      if (this.dataSourceProcess) {
        //自定义的数据处理过程
        that.ctl.dataReal = this.dataSourceProcess(resultData)
      } else {
        that.ctl.dataReal = resultData
      }
      YvEventDispatch(that.ctl.onDataComplete, that.ctl, undefined)

    }).catch(r => {
      that.ctl.dataReal = []

    }).finally(() => {
      that.ctl.loading = false

    })
  });

  /**
   * 自定义函数式取值
   */
  setCustomFunctionMode(option: DataSourceStaticFunction<T>) {
    const that = this
    this.reload = () => {
      that.customFunctionModeDebounce(option)
    }
    this.reload()
  }

  /**
   * SQL取值
   */
  setSqlMode(option: DataSourceDb<T> | DataSourceServer<T>) {
    const that = this
    this.reload = () => {
      that.sqlModeDebounce(option)
    }
    this.reload()
  }

  constructor(ctl: any, option: DataSource<T>, dataSourceProcess?: DataSourceProcessFunction) {
    if (ctl._webix.$scope.isDesignMode === true) {
      return
    }
    this.ctl = ctl
    this.option = option
    this.dataSourceProcess = dataSourceProcess
    this.module = ctl._webix.$scope
  }

  public init() {
    if (!this.option) {
      //没有设值，退出
      this.reload = undefined
      return
    }

    if (typeof this.option === 'function') {
      //以 function 方式运行
      this.setCustomFunctionMode(this.option)
      return
    }

    if (_.isArray(this.option)) {
      //结果就是数组
      this.reload = () => {
        this.ctl.dataReal = this.option
        this.ctl.$yvDispatch(this.ctl.onDataComplete)
      }
      this.reload()
      return
    }

    // 使 watch 生效
    _.each(this.option.watch, watchExp => {
      const unwatch = this.module.$watch(watchExp, () => {
        if (this.reload) {
          this.reload()
        }
      })
      this.watches.push(unwatch)
    })

    if (this.option.type === 'function') {
      // 取 bind 函数
      if (typeof this.option.bind === 'function') {
        this.setCustomFunctionMode(this.option.bind)
      } else {
        const bindFunction: DataSourceStaticFunction<T> = _.get(
          this.module,
          this.option.bind
        ) as DataSourceStaticFunction<T>
        if (!bindFunction) {
          console.error(`没有找到名称为 ${this.option.bind} 的方法`)
          return
        }
        this.setCustomFunctionMode(bindFunction)
      }
    } else if (this.option.type === 'SQL' || this.option.type === 'Server') {
      this.setSqlMode(this.option)
    } else {
      console.error(`其他方式没有实现`)
    }
  }

  destory() {
    // 解除全部 watch
    _.each(this.watches, unwatch => {
      unwatch()
    })
    this.reload = undefined
    if (this.ctl) {
      // ctl 对象可能已经被移除
      this.ctl.dataReal = []
    }
  }
}