import { Injectable } from '@angular/core';
import { Http, Response } from '@angular/http';

import { Observable } from 'rxjs';

import { IConfigurationService } from './config.interface';
import { ConfigData } from './config.modal';

@Injectable()
export class ConfigService implements IConfigurationService {
    private http: Http;
    private configIsLoaded: boolean;

    constructor (http: Http) {
        this.http = http;
    }

    private handleError (error: any) {
        let that: ConfigService = this;
        let errMsg = (error.message) ? error.message :
        error.status ? `${error.status} - ${error.statusText}` : 'Server error';

        this.configIsLoaded = false;
        console.error(errMsg); // log to console instead
        return Observable.throw(errMsg);
    }

    public retrieveConfigData(): Observable<ConfigData> {
        return this.http.get('./config/config.json')
        .map((response: Response) => {
            let that: ConfigService = this;
            that.configIsLoaded = true;

            return <ConfigData>response.json();
        })
        .catch(this.handleError);
    }

    public get isLoaded(): boolean {
        return this.configIsLoaded;
    }
}