app/main.py

from fastapi import FastAPI, Request, status
from fastapi.responses import JSONResponse
from fastapi.responses import Response
from fastapi.exceptions import HTTPException
from fastapi.background import BackgroundTasks
from slowapi import Limiter, _rate_limit_exceeded_handler
from slowapi.errors import RateLimitExceeded
from slowapi.util import get_remote_address
from slowapi.middleware import SlowAPIMiddleware
from typing import Dict, List
from prometheus_client import Counter, Histogram, start_http_server
from pydantic import BaseModel, ValidationError
from app.services.message import generate_reply, send_reply
import logging
import httpx
from datetime import datetime
from sentence_transformers import SentenceTransformer
from app.search.rag_pipeline import RAGSystem
from contextlib import asynccontextmanager
# from app.db.database import create_indexes, init_db
# from app.services.webhook_handler import verify_webhook
from app.handlers.message_handler import MessageHandler
from app.handlers.webhook_handler import WebhookHandler
from app.handlers.media_handler import WhatsAppMediaHandler
from app.services.cache import MessageCache
from app.services.chat_manager import ChatManager
from app.api.api_prompt import prompt_router
from app.api.api_file import file_router, load_file_with_markdown_function
from app.utils.load_env import ACCESS_TOKEN, WHATSAPP_API_URL, GEMINI_API


from markitdown import MarkItDown

# Configure logging
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
)

logger = logging.getLogger(__name__)

# Initialize handlers at startup
message_handler = None
webhook_handler = None

indexed_links = ["https://sswalfa.surabaya.go.id/info/detail/izin-pengumpulan-sumbangan-bencana",
        "https://sswalfa.surabaya.go.id/info/detail/izin-pemakaian-ruang-terbuka-hijau",
        "https://sswalfa.surabaya.go.id/info/detail/pengganti-ipt",
        "https://sswalfa.surabaya.go.id/info/detail/arahan-sistem-drainase",
        "https://sswalfa.surabaya.go.id/info/detail/rangkaian-pelayanan-surat-pernyataan-belum-menikah-lagi-bagi-jandaduda"
    ]


async def setup_message_handler():
    logger = logging.getLogger(__name__)
    message_cache = MessageCache()
    chat_manager = ChatManager()
    media_handler = WhatsAppMediaHandler()
    
    
    return MessageHandler(
        message_cache=message_cache,
        chat_manager=chat_manager,
        media_handler=media_handler,
        logger=logger
    )
async def setup_rag_system():
    embedding_model = SentenceTransformer('all-MiniLM-L6-v2')  # Replace with your model if different
    rag_system = RAGSystem(embedding_model)


    return rag_system
# Initialize FastAPI app
@asynccontextmanager
async def lifespan(app: FastAPI):
   
    
    try:
        # await init_db()
      
        logger.info("Connected to the MongoDB database!")
        rag_system = await setup_rag_system()

        app.state.rag_system = rag_system

        global message_handler, webhook_handler
        message_handler = await setup_message_handler()
        webhook_handler = WebhookHandler(message_handler)
        # collections = app.database.list_collection_names()
        # print(f"Collections in {db_name}: {collections}")
        await load_file_with_markdown_function(rag_system=rag_system, filepaths=indexed_links)
        yield
    except Exception as e:
        logger.error(e)

# Initialize Limiter and Prometheus Metrics
limiter = Limiter(key_func=get_remote_address)
app = FastAPI(lifespan=lifespan)
app.state.limiter = limiter
app.add_exception_handler(RateLimitExceeded, _rate_limit_exceeded_handler)

# Add SlowAPI Middleware
app.add_middleware(SlowAPIMiddleware)

# app.include_router(users.router, prefix="/users", tags=["Users"])
app.include_router(prompt_router, prefix="/prompts", tags=["Prompts"])
app.include_router(file_router, prefix="/file_load", tags=["File Load"])
# Prometheus metrics
webhook_requests = Counter('webhook_requests_total', 'Total webhook requests')
webhook_processing_time = Histogram('webhook_processing_seconds', 'Time spent processing webhook')

# Start Prometheus metrics server on port 8002
# start_http_server(8002)
# Register webhook routes
# app.post("/webhook")(webhook)
# Define Pydantic schema for request validation
class WebhookPayload(BaseModel):
    entry: List[Dict]

@app.post("/webhook")
# @limiter.limit("20/minute")
async def webhook(request: Request, background_tasks: BackgroundTasks):
    try:
        payload = await request.json()

        rag_system = request.app.state.rag_system
        # validated_payload = WebhookPayload(**payload)  # Validate payload
        # logger.info(f"Validated Payload: {validated_payload}")
            
            # Process the webhook payload here
            # For example:
        # results = process_webhook_entries(validated_payload.entry)
         # e.g., whatsapp_token, verify_token, llm_api_key, llm_model
        whatsapp_token = request.query_params.get("whatsapp_token")
        whatsapp_url = request.query_params.get("whatsapp_url")
        gemini_api = request.query_params.get("gemini_api")
        llm_model = request.query_params.get("cx_code")

          # Return HTTP 200 immediately
        # response = JSONResponse(
        #     content={"status": "received"},
        #     status_code=200
        # )
        
        print(f"payload: {payload}")
        # response = await webhook_handler.process_webhook(
        #     payload=payload,
        #     whatsapp_token=ACCESS_TOKEN,
        #     whatsapp_url=WHATSAPP_API_URL,
        #     gemini_api=GEMINI_API,
        #     rag_system=rag_system,
        # )

          # Add the processing to background tasks
        background_tasks.add_task(
            webhook_handler.process_webhook,
            payload=payload,
            whatsapp_token=ACCESS_TOKEN,
            whatsapp_url=WHATSAPP_API_URL,
            gemini_api=GEMINI_API,
            rag_system=rag_system,
        )
        # Return HTTP 200 immediately
        return JSONResponse(
            content={"status": "received"},
            status_code=status.HTTP_200_OK
        )
        # return JSONResponse(
        #     content=response.__dict__,
        #     status_code=status.HTTP_200_OK
        # )
        
    except ValidationError as ve:
            logger.error(f"Validation error: {ve}")
            return JSONResponse(
                content={"status": "error", "detail": ve.errors()},
                status_code=status.HTTP_422_UNPROCESSABLE_ENTITY
            )
    except Exception as e:
            logger.error(f"Unexpected error: {str(e)}")
            return JSONResponse(
                content={"status": "error", "detail": str(e)},
                status_code=status.HTTP_500_INTERNAL_SERVER_ERROR
            )

@app.get("/webhook")
async def verify_webhook(request: Request):
    mode = request.query_params.get('hub.mode')
    token = request.query_params.get('hub.verify_token')
    challenge = request.query_params.get('hub.challenge')

    if mode == 'subscribe' and token == 'test':
        return Response(content=challenge, media_type="text/plain")
    else:
        raise HTTPException(status_code=403, detail="Verification failed") 
    
@app.post("/load_file")
async def load_file_with_markitdown(file_path:str, llm_client:str=None, model:str=None):
    
    if llm_client and model:
        markitdown = MarkItDown(llm_client, model)
        documents = markitdown.convert(file_path)
    else:
        markitdown = MarkItDown()
        documents = markitdown.convert(file_path)

    print(f"documents: {documents}")
    return documents

# Add a route for Prometheus metrics (optional, if not using a separate Prometheus server)
@app.get("/metrics")
async def metrics():
    from prometheus_client import generate_latest
    return Response(content=generate_latest(), media_type="text/plain")

# In-memory cache with timestamp cleanup
# class MessageCache:
#     def __init__(self, max_age_hours: int = 24):
#         self.messages: Dict[str, float] = {}
#         self.max_age_seconds = max_age_hours * 3600

#     def add(self, message_id: str) -> None:
#         self.cleanup()
#         self.messages[message_id] = time.time()

#     def exists(self, message_id: str) -> bool:
#         self.cleanup()
#         return message_id in self.messages

#     def cleanup(self) -> None:
#         current_time = time.time()
#         self.messages = {
#             msg_id: timestamp 
#             for msg_id, timestamp in self.messages.items()
#             if current_time - timestamp < self.max_age_seconds
#         }

# message_cache = MessageCache()
# user_chats = {}