// tslint:disable:no-console class-name
import { HttpClient, HttpHeaders, HttpParams } from '@angular/common/http';
import { Injectable } from '@angular/core';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/do';
import * as moment from 'moment';
import { environment } from '../../../environments/environment';

/**
 * 封装HttpClient，主要解决：
 * + 优化HttpClient在参数上便利性
 * + 统一实现 loading
 * + 统一处理时间格式问题
 */
@Injectable()
export class _HttpClient {
    constructor(private http: HttpClient) { }

    private _loading = false;

    /** 是否正在加载中 */
    get loading(): boolean {
        return this._loading;
    }

    parseParams(params: any): HttpParams {
        let ret = new HttpParams();
        if (params) {
            // tslint:disable-next-line:forin
            for (const key in params) {
                let _data = params[key];
                // 将时间转化为：时间戳 (秒)
                if (moment.isDate(_data)) {
                    _data = moment(_data).unix();
                }
                ret = ret.set(key, _data);
            }
        }
        return ret;
    }

    private begin() {
        console.time('http');
        this._loading = true;
    }

    private end() {
        console.timeEnd();
        this._loading = false;
    }

    /** 服务端URL地址 */
    get SERVER_URL(): string {
        return environment.SERVER_URL;
    }

    /**
     * GET请求
     *
     * @param {string} url URL地址
     * @param {*} [params] 请求参数
     */
    get(url: string, params?: any): Observable<any> {
        this.begin();
        return this.http
            .get(url, {
                params: this.parseParams(params)
            })
            .do(() => this.end())
            .catch((res) => {
                this.end();
                return res;
            });
    }

    /**
     * POST请求
     *
     * @param {string} url URL地址
     * @param {*} [body] body内容
     * @param {*} [params] 请求参数
     */
    post(url: string, body?: any, params?: any): Observable<any> {
        this.begin();
        return this.http
            .post(url, body || null, {
                params: this.parseParams(params)
            })
            .do(() => this.end())
            .catch((res) => {
                this.end();
                return res;
            });
    }

    /**
     * DELETE请求
     *
     * @param {string} url URL地址
     * @param {*} [params] 请求参数
     */
    delete(url: string, params?: any): Observable<any> {
        this.begin();
        return this.http
            .delete(url, {
                params: this.parseParams(params)
            })
            .do(() => this.end())
            .catch((res) => {
                this.end();
                return res;
            });
    }
}