import * as line from "@line/bot-sdk";
import dateFormat from "dateformat";
import express from "express";
import fs from "fs";
import { IncomingMessage, ServerResponse } from "http";
import https from "https";
import MemberJoinedClass from "./MemberJoinedClass";
import MessageClass from "./MessageClass";

/**
 * LineBot
 */
export default class LineBotClass {

	//#region private

	private bot: line.Client = null;

	private message: MessageClass;
	private memberJoined: MemberJoinedClass;

	//#endregion

	//#region Lifecycle

	/**
	 *
	 */
	constructor() {
		//讀取憑證及金鑰
		const prikey: string = fs.readFileSync("/certificate/RSA-privkey.pem", "utf8");
		const cert: string = fs.readFileSync("/certificate/RSA-cert.pem", "utf8");
		const cafile: string = fs.readFileSync("/certificate/RSA-chain.pem", "utf-8");

		//建立憑證及金鑰
		const credentials: Object = {
			key: prikey,
			cert: cert,
			ca: cafile
		};

		// 用於辨識Line Channel的資訊
		const config: any = {
			channelSecret: process.env.channelSecret,
			channelAccessToken: process.env.channelAccessToken || ""
		};
		this.bot = new line.Client(config);
		this.message = new MessageClass(this.bot);
		this.memberJoined = new MemberJoinedClass(this.bot);
		// const ZhuHanbot: linebot.Client = new linebot.Client({
		// 	channelSecret: process.env.ZhuHanchannelSecret,
		// 	channelAccessToken: process.env.ZhuHanchannelAccessToken || ""
		// });


		// Bot所監聽的webhook路徑與port
		const path: string = process.env.URLPATH || "/";
		const port: number = +process.env.PORT || 3000;
		// tslint:disable-next-line:typedef
		const app = express();
		const httpsServer: https.Server<typeof IncomingMessage, typeof ServerResponse> = https.createServer(credentials, app);
		app.post(path, line.middleware(config), (req, res) => {
			Promise
				.all(req.body.events.map(this.handleEvent.bind(this)))
				.then((result) => res.json(result));
		});
		httpsServer.listen(port, () => {
			let datetime: string = dateFormat(new Date(), "yyyy-mm-dd HH:MM:ss");
			console.log(`${datetime} listening on ${port}`);
			console.log(`${datetime} [BOT已準備就緒]`);
		});
	}

	//#endregion

	//#region Custom

	private async handleEvent(event: any): Promise<any> {
		switch (event.type) {
			case "message": {
				this.message.Message(event);
				break;
			}

			case "postback": {
				// self.Postback.Postback(event);
				return Promise.resolve(null);
			}

			case "join":
			case "leave":
			case "follow":
			case "unfollow":

			case "memberJoin": {
				this.memberJoined.MemberJoined(event);
				break;
			}

			case "memberLeave":
			case "accountLink":
			case "fallback":
			default: {
				return Promise.resolve(null);
			}
		}
		// if (event.type !== "message" || event.message.type !== "text") {
		// 	return Promise.resolve(null);
		// }

		// return this.bot.replyMessage(event.replyToken, {
		// 	type: "text",
		// 	text: event.message.text
		// });
	}

	//#endregion
}