main.py

from fastapi.middleware.cors import CORSMiddleware
from fastapi import FastAPI, Request,  Header, BackgroundTasks, HTTPException, status, staticfiles
from gradio_client import Client
import json
import os

from linebot import (
    LineBotApi, WebhookHandler
)
from linebot.exceptions import (
    InvalidSignatureError
)
from linebot.models import (
    MessageEvent, TextMessage, TextSendMessage, ImageSendMessage, AudioMessage
)

# 設定 GeminiRAG 的HF網址
client = Client(os.environ["GeminiRAGapi"], hf_token=os.environ['HF_TOKEN'])
# 設定 Line Bot 的 API 金鑰和秘密金鑰
line_bot_api = LineBotApi(os.environ["CHANNEL_ACCESS_TOKEN"])
line_handler = WebhookHandler(os.environ["CHANNEL_SECRET"])
# 設定是否正在與使用者交談
working_status = os.getenv("DEFALUT_TALKING", default = "true").lower() == "true"

# 建立 FastAPI 應用程式
app = FastAPI()
# app.mount("/static", staticfiles.StaticFiles(directory="static"), name="static")

# 設定 CORS，允許跨域請求
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# 處理根路徑請求
@app.get("/")
def root():
    return {"title": "RAG Line Bot"}

# 處理 Line Webhook 請求
@app.post("/webhook")
async def webhook(
    request: Request,
    background_tasks: BackgroundTasks,
    x_line_signature=Header(None),
):
    # 取得請求內容
    body = await request.body()
    try:
        # 將處理 Line 事件的任務加入背景工作
        background_tasks.add_task(
            line_handler.handle, body.decode("utf-8"), x_line_signature
        )
    except InvalidSignatureError:
        # 處理無效的簽章錯誤
        raise HTTPException(status_code=400, detail="Invalid signature")
    return "ok"

# 處理文字訊息事件
@line_handler.add(MessageEvent, message=TextMessage)
def handle_message(event):
    global working_status
    
    # 檢查事件類型和訊息類型
    if event.type != "message" or event.message.type != "text":
        # 回覆錯誤訊息
        line_bot_api.reply_message(
            event.reply_token,
            TextSendMessage(text="Event type error:[No message or the message does not contain text]")
        )
        
    # 檢查使用者是否輸入 "再見"
    elif event.message.text == "再見":
        # 回覆 "Bye!"
        line_bot_api.reply_message(
            event.reply_token,
            TextSendMessage(text="Bye!")
        )
        return
       
    # 檢查是否正在與使用者交談
    elif working_status:
        try: 
            # 取得使用者輸入的文字
            prompt = event.message.text
            # 使用 GeminiRAGapi
            completion = client.predict(question=prompt, api_name="/predict")
            # 檢查生成結果是否為空
            if (completion != None):
                # 取得生成結果
                out = completion
            else:
                # 回覆 "Gemini沒答案!請換個說法！"
                out = "Gemini沒答案!請換個說法！"
        except:
            # 處理錯誤
            out = "Gemini執行出錯!請換個說法！" 
  
        # 回覆生成結果
        line_bot_api.reply_message(
            event.reply_token,
            TextSendMessage(text=out))

if __name__ == "__main__":
    # 啟動 FastAPI 應用程式
    uvicorn.run("main:app", host="0.0.0.0", port=7860, reload=True)