import EventEmitter from "./event-emitter";
import { LOADED, LOADING } from "../constant/context";
import { Mode, Platform } from "../types/page";

/**
 * page render context
 */
export default class Context extends EventEmitter {
  public $mode: Mode;
  public $platform: Platform;
  // 渲染状态队列
  private $loadingQueue: Array<string> = [];
  private $loadedQueue: Array<string> = [];
  public $mixins: Record<string, Function>[] = [];
  // 页面数据源
  // private $source: Record<string, any> = {};

  constructor(mode: Mode = "edit", platform: Platform = "auto") {
    super();

    this.$mode = mode;
    this.$platform = platform;
  }

  /**
   * 设置mode
   * @param mode
   */
  setMode(mode: Mode) {
    if (mode) {
      this.$mode = mode;
    }
  }

  /**
   * 设置platform
   * @param platform
   */
  setPlatform(platform: Platform) {
    if (platform) {
      this.$platform = platform;
    }
  }

  /**
   * 全局混入
   * @param mixin
   */
  addMixins(mixin: Record<string, Function>) {
    if (this.$mixins.indexOf(mixin) === -1) {
      this.$mixins.push(mixin);
    }
  }

  /**
   * 执行全局混入方法
   * @param name
   * @param args
   */
  invokeMixin(name: string, ...args: any[]) {
    this.$mixins.forEach((mixin) => {
      if (typeof mixin[name] === "function") {
        mixin[name].apply(null, args);
      }
    });
  }

  /**
   * 重置
   */
  public reset() {
    this.removeAllListener();
    this.$loadingQueue = [];
    this.$loadedQueue = [];
  }

  /**
   * 创建加载组价记录
   * @param uid
   */
  public createLoading(uid: string) {
    this.$loadingQueue.push(uid);
    this.emit(
      LOADING,
      uid,
      Math.ceil(
        (this.$loadedQueue.length * 100) / (this.$loadingQueue.length + this.$loadedQueue.length)
      )
    );

    return () => {
      this.$loadedQueue.push(uid);
      this.$loadingQueue = this.$loadingQueue.filter((_uid) => _uid !== uid);

      let type: string = LOADING;
      if (this.$loadingQueue.length === 0) {
        type = LOADED;
      }

      this.emit(
        type,
        uid,
        Math.ceil(
          (this.$loadedQueue.length * 100) / (this.$loadingQueue.length + this.$loadedQueue.length)
        )
      );
    };
  }
}