import logging
import os
import time
from typing import Dict, List

from fastapi import FastAPI, HTTPException

from .db import fetch_recent_transactions, log_api_hit
from .schemas import InsightRequest, InsightResponse, Transaction
from .services import generate_insights

logging.basicConfig(
    level=os.environ.get("LOG_LEVEL", "INFO"),
    format="%(asctime)s %(levelname)s [%(name)s] %(message)s",
)
logger = logging.getLogger(__name__)

app = FastAPI(
    title="AI Financial Insights",
    description="AI-powered personalized spending insight generator for WalletSync.",
    version="1.0.0",
)


@app.get("/")
def root() -> Dict[str, str]:
    """Simple description endpoint."""
    return {
        "message": "AI Financial Insights is ready. POST /insights with transactions to receive insights.",
        "docs": "/docs",
    }


@app.get("/health")
def health() -> Dict[str, str]:
    """Health probe for monitoring."""
    return {"status": "ok"}


def _resolve_transactions(payload: InsightRequest) -> List[Transaction]:
    if payload.transactions:
        return payload.transactions
    if not payload.user_id:
        raise HTTPException(
            status_code=400,
            detail="Provide `transactions` or `user_id` to fetch them from MongoDB.",
        )
    try:
        return fetch_recent_transactions(payload.user_id)
    except ValueError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    except Exception as exc:  # noqa: BLE001
        logger.exception("Failed to fetch MongoDB data for user_id=%s", payload.user_id)
        raise HTTPException(status_code=502, detail="Unable to query transaction store.") from exc


@app.post("/insights", response_model=InsightResponse)
def create_insights(payload: InsightRequest) -> InsightResponse:
    """Generate insights from a transaction payload."""
    start_time = time.time()
    status = "success"
    # Capture user_id directly from request body - store exactly what is passed
    user_id = payload.user_id
    
    try:
        logger.info("Received request for user_id=%s", user_id)
        transactions = _resolve_transactions(payload)
        insights, months = generate_insights(transactions)
        response = InsightResponse(user_id=user_id, insights=insights, evaluated_months=months)
        return response
    except HTTPException:
        status = "error"
        raise
    except Exception as exc:  # noqa: BLE001
        status = "error"
        logger.exception("Unexpected error processing insights request for user_id=%s", user_id)
        raise HTTPException(status_code=500, detail="Internal server error") from exc
    finally:
        response_time = time.time() - start_time
        try:
            # Log with the exact user_id from request body (can be None if not provided)
            log_api_hit(user_id, status, response_time)
        except Exception as log_exc:  # noqa: BLE001
            # Don't fail the request if logging fails
            logger.warning("Failed to log API hit: %s", log_exc)



# import logging
# import os
# from typing import Dict, List

# from fastapi import FastAPI, HTTPException

# from .db import fetch_recent_transactions
# from .schemas import InsightRequest, InsightResponse, Transaction
# from .services import generate_insights

# logging.basicConfig(
#     level=os.environ.get("LOG_LEVEL", "INFO"),
#     format="%(asctime)s %(levelname)s [%(name)s] %(message)s",
# )
# logger = logging.getLogger(__name__)

# app = FastAPI(
#     title="AI Financial Insights",
#     description="AI-powered personalized spending insight generator for WalletSync.",
#     version="1.0.0",
# )


# @app.get("/")
# def root() -> Dict[str, str]:
#     """Simple description endpoint."""
#     return {
#         "message": "AI Financial Insights is ready. POST /insights with transactions to receive insights.",
#         "docs": "/docs",
#     }


# @app.get("/health")
# def health() -> Dict[str, str]:
#     """Health probe for monitoring."""
#     return {"status": "ok"}


# def _resolve_transactions(payload: InsightRequest) -> List[Transaction]:
#     if payload.transactions:
#         return payload.transactions
#     if not payload.user_id:
#         raise HTTPException(
#             status_code=400,
#             detail="Provide `transactions` or `user_id` to fetch them from MongoDB.",
#         )
#     try:
#         return fetch_recent_transactions(payload.user_id)
#     except ValueError as exc:
#         raise HTTPException(status_code=400, detail=str(exc)) from exc
#     except Exception as exc:  # noqa: BLE001
#         logger.exception("Failed to fetch MongoDB data for user_id=%s", payload.user_id)
#         raise HTTPException(status_code=502, detail="Unable to query transaction store.") from exc


# @app.post("/insights", response_model=InsightResponse)
# def create_insights(payload: InsightRequest) -> InsightResponse:
#     """Generate insights from a transaction payload."""
#     logger.info("Received request for user_id=%s", payload.user_id)
#     transactions = _resolve_transactions(payload)
#     insights, months = generate_insights(transactions)
#     return InsightResponse(user_id=payload.user_id, insights=insights, evaluated_months=months)