import * as _ from "lodash";
import { StorageService } from './StorageService';
import { Parser, safeParse } from './Parsers';
import { Marshaller } from './Marshallers';
export const Prefix = "ovo";

export class LocalStorageService implements StorageService {
  constructor(private $window: ng.IWindowService) { }

  get<T>(key: string, parse: Parser<T>): T;
  get<T extends string>(key: string): T;
  get<T>(key: string, parser?: Parser<T>) {
    let value = this.$window.localStorage.getItem(`${Prefix}.${key}`);
    // Check null/undefined explicitly, because the parse function may not cope
    if (!value) return undefined;
    return (parser) ? safeParse(parser, value) : value;
  }

  set<T>(key: string, value: T, marshal: Marshaller<T>): void;
  set<T extends string>(key: string, value: T): void;
  set<T>(key: string, value: T, marshal?: Marshaller<T>) {
    if (_.isNil(value))
      this.$window.localStorage.removeItem(`${Prefix}.${key}`);
    else
      this.$window.localStorage.setItem(`${Prefix}.${key}`, marshal ? marshal(value) : value as any);
  }

  contains(key: string): boolean {
    return `${Prefix}.${key}` in this.$window.localStorage;
  }
}