main.go

// 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.

package main

import (
	"fmt"
	"log"
	"net/http"
	"os"
	"strconv"

	"github.com/line/line-bot-sdk-go/v8/linebot"
	"github.com/line/line-bot-sdk-go/v8/linebot/webhook"
)

var bot *linebot.Client

func main() {
	var err error
	bot, err = linebot.New(os.Getenv("ChannelSecret"), os.Getenv("ChannelAccessToken"))
	log.Println("Bot:", bot, " err:", err)
	http.HandleFunc("/callback", callbackHandler)
	port := os.Getenv("PORT")
	addr := fmt.Sprintf(":%s", port)
	http.ListenAndServe(addr, nil)
}

func callbackHandler(w http.ResponseWriter, r *http.Request) {
	cb, err := webhook.ParseRequest(os.Getenv("ChannelSecret"), r)
	if err != nil {
		if err == linebot.ErrInvalidSignature {
			w.WriteHeader(400)
		} else {
			w.WriteHeader(500)
		}
		return
	}

	for _, event := range cb.Events {
		log.Printf("Got event %v", event)
		switch e := event.(type) {
		case webhook.MessageEvent:
			switch message := e.Message.(type) {
			// Handle only on text message
			case webhook.TextMessageContent:
				// GetMessageQuota: Get how many remain free tier push message quota you still have this month. (maximum 500)
				quota, err := bot.GetMessageQuota().Do()
				if err != nil {
					log.Println("Quota err:", err)
				}
				// message.ID: Msg unique ID
				// message.Text: Msg text
				if _, err = bot.ReplyMessage(e.ReplyToken, linebot.NewTextMessage("msg ID:"+message.Id+":"+"Get:"+message.Text+" , \n OK! remain message:"+strconv.FormatInt(quota.Value, 10))).Do(); err != nil {
					log.Print(err)
				}

			// Handle only on Sticker message
			case webhook.StickerMessageContent:
				var kw string
				for _, k := range message.Keywords {
					kw = kw + "," + k
				}

				outStickerResult := fmt.Sprintf("收到貼圖訊息: %s, pkg: %s kw: %s  text: %s", message.StickerId, message.PackageId, kw, message.Text)
				if _, err = bot.ReplyMessage(e.ReplyToken, linebot.NewTextMessage(outStickerResult)).Do(); err != nil {
					log.Print(err)
				}
			default:
				log.Printf("Unknown message: %v", message)
			}
		case webhook.FollowEvent:
			log.Printf("message: Got followed event")
		case webhook.PostbackEvent:
			data := e.Postback.Data
			log.Printf("Unknown message: Got postback: " + data)
		case webhook.BeaconEvent:
			log.Printf("Got beacon: " + e.Beacon.Hwid)
		}
	}
}