import * as localForage from 'localforage';

export interface IRequestCache {
  url: string; // 匹配 url，必填
  retry?: number; // 错误重试次数，非必填，默认为 0
  method?: 'get' | 'post' | 'put' | 'delete'; // 接口请求方法，默认为 'get'
  maxAge?: number; // 接口存储保留时间，默认为无限制
  maxRows?: number; // 接口存储规格上限配置，默认 10 条
  timeout?: number; // 前端判断接口超时时间，非必填，默认为无限制
  degradedTime?: number; // 接口熔断时间，非必填，默认为30秒
  withHeaders?: string[]; // 需要识别的 header，非必填，默认为空
  ignoreUrlParams?: string[]; // 需要忽略的 url 参数，非必填，默认为空，即会保存携带不同参数的所有url
  withBodys?: string[]; // 区分请求体不同的请求
  excludeStatusCode?: number[]; // 忽略的http状态码
}

export class StorageService {
  instanceName = '';
  instanceMap:any = {};
  requestCacheList: IRequestCache[] = [];
  SINGLE_SIZE_LIMIT =  1024 * 1024; //单条数据大小限制1M
  TOTAL_NUMBER_LIMIT = 200; //单数据库实例存储条数不超过200

  setRequestCacheList(requestCacheList: IRequestCache[]) {
    this.requestCacheList = requestCacheList;
  }

  getRequestCacheList() {
    return this.requestCacheList;
  }
  

  setInstanceName(name: string) {
    this.instanceName = name;
  }

  getInstance(name: string) {
    if (!this.instanceMap[name]) {
      this.instanceMap[name] = localForage.createInstance({
        name: `GitcodeDB_${name}`,
        storeName: `GitcodeStore_${name}`,
      });
    }
    return this.instanceMap[name];
  }
  setItem(key: string, value: any, instanceName = this.instanceName) {
    const store = this.getInstance(instanceName);
    this.chkAndCtlIntSize(store);
    store.setItem(key, value);
  }

  getItem(key: string, instanceName = this.instanceName) {
    const store = this.getInstance(instanceName);
    return store.getItem(key);
  }

  removeItem(key: string, instanceName = this.instanceName) {
    const store = this.getInstance(instanceName);
    store.removeItem(key);
  }

  // 控制数据库总条数，超过后删除最早的一条
  chkAndCtlIntSize(store: any, size = this.TOTAL_NUMBER_LIMIT) {
    store.keys().then((keys: any) => {
      const len = keys.length;
      if (len > size) {
        store.removeItem(keys[0]);
      }
    });
  }

  // 获取字符串占用存储大小
  sizeOf(str: any) {
    let total = 0;
    let charCode;
    str.split('').forEach((element: any, index: any) => {
      charCode = str.charCodeAt(index);
      if (charCode <= 0x007f) {
        total += 1;
      } else if (charCode <= 0x07ff) {
        total += 2;
      } else if (charCode <= 0xffff) {
        total += 3;
      } else {
        total += 4;
      }
    });
    return total;
  }
}

export const storageService = new StorageService();