import {Injectable} from '@angular/core';
import {PouchDBService} from '../database/pouchdb.service';
import {RecordCollection} from './record-collection';
import _ from 'lodash';
import {Observable, Subject} from 'rxjs/Rx';
import 'rxjs/Rx';

@Injectable()
export class RecordStoreService {
  db: PouchDB;
  streams: IRecordStoreEmitters;

  constructor(dbService: PouchDBService) {
    this.db = dbService.createDatabase('records-collection');
    this.streams = {
      put: new Subject<RecordCollection>()
    };
  }

  put(collection: RecordCollection): Observable<PouchUpdateResponse> {
    const observable = Observable.fromPromise(
      this.db.put(collection.serialize())
    );

    observable.subscribe(info => {
      collection.rev = info.rev;
      this.streams.put.next(collection);
    });

    return observable;
  }

  get(id: string): Observable<RecordCollection> {
    return Observable.fromPromise(this.db.get(id))
      .map(res => new RecordCollection(res));
  }

  remove(collection: RecordCollection): Observable<PouchUpdateResponse> {
    return Observable.fromPromise(
      this.db.remove(collection.id, collection.rev)
    );
  }

  allDocs(
    opts: PouchAllDocsOptions = {include_docs: true})
  : Observable<RecordCollection[]> {
    return Observable.fromPromise(this.db.allDocs(opts))
      .map((res: PouchAllDocsResponse) => {
        return _.map(
          res.rows,
          row => new RecordCollection(row.doc)
        );
      });
  }
}

export interface IRecordStoreEmitters {
  put: Subject<RecordCollection>;
}