/*!
 * @license
 * Copyright 2016 Alfresco Software, Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import { APP_INITIALIZER, Injectable, NgModule } from '@angular/core';
import { Http, HttpModule } from '@angular/http';
import { ObjectUtils } from '../utils/object-utils';

@Injectable()
export class AppConfigService {

    config: any = {
        application: {
            name: 'Alfresco ADF Application'
        },
        ecmHost: 'http://{hostname}:{port}/ecm',
        bpmHost: 'http://{hostname}:{port}/bpm'
    };

    constructor(private http: Http) {}

    get<T>(key: string, defaultValue?: T): T {
        let result: any = ObjectUtils.getValue(this.config, key);
        if (typeof result === 'string') {
            const map = new Map<string, string>();
            map.set('hostname', location.hostname);
            map.set('port', location.port);
            result = this.formatString(result, map);
        }
        if (result === undefined) {
            return defaultValue;
        }
        return <T> result;
    }

    load(): Promise<any> {
        return new Promise(resolve => {
            this.http.get('app.config.json').subscribe(
                data => {
                    this.config = Object.assign({}, this.config, data.json() || {});
                    resolve(this.config);
                },
                () => {
                    resolve(this.config);
                }
            );
        });
    }

    private formatString(str: string, map: Map<string, string>): string {
        let result = str;

        map.forEach((value, key) => {
            const expr = new RegExp('{' + key + '}', 'gm');
            result = result.replace(expr, value);
        });

        return result;
    }
}

export function startupServiceFactory(configService: AppConfigService): Function {
    return () => configService.load();
}

@NgModule({
    imports: [
        HttpModule
    ],
    providers: [
        AppConfigService,
        {
            provide: APP_INITIALIZER,
            useFactory: startupServiceFactory,
            deps: [
                AppConfigService
            ],
            multi: true
        }
    ]
})
export class AppConfigModule {}