import logging
from typing import Optional
from datetime import datetime, timedelta
from fastapi import APIRouter, HTTPException, Query, Depends, status, Body
from app.models.merchant import MerchantRegister, GetOtpRequest
from app.services.merchant_services import generate_and_send_otp, get_otp_from_cache, verify_otp_and_save_merchant, validate_merchant


# Initialize router and logger
router = APIRouter(prefix="/merchant")
logger = logging.getLogger(__name__)



@router.post("/register")
async def register_customer(user: MerchantRegister = Body(...)):
    """
    API endpoint to register a new Merchant.

    Args:
        user (MerchantRegister): The details of the Merchant to register.

    Returns:
        dict: Confirmation message indicating email and SMS verification pending.
    """
    try:
        logger.info("Registering a new Merchant with Merchant name : %s, email: %s and mobile: %s", user.merchant_name, user.email, user.mobile)

        # Validate email and mobile format
        validation_result = await validate_merchant(user)
        if validation_result["status"] == "error":
            logger.error("Validation failed: %s", validation_result["errors"])
            raise HTTPException(status_code=400, detail=validation_result["errors"])       

        return user.dict()

    except HTTPException as e:
        logger.error("Failed to register merchant: %s", e.detail)
        raise e
    except Exception as e:
        logger.error("Unexpected error while registering merchant: %s", e)
        raise HTTPException(status_code=500, detail="Failed to register Merchant") from e
    
@router.post("/otp/verify")
async def customer_otp_verification(user: MerchantRegister = Body(...)):
    """
    API endpoint to validate OTPs and save the complete Merchant object.

    Args:
        user (MerchantRegister): The complete Merchant object including email, mobile, and OTPs.

    Returns:
        dict: Confirmation message indicating success or failure.
    """
    try:
        logger.info("Verifying OTPs and registering merchant with email: %s and mobile: %s", user.email, user.mobile)
         # Verify OTPs and save customer
        result = await verify_otp_and_save_merchant(user)
        if result["status"] == "error":
            raise HTTPException(status_code=400, detail=result["errors"])

        return {"message": "Merchant successfully registered and verified."}

    except HTTPException as e:
        logger.error("Failed to verify and register merchant: %s", e.detail)
        raise e
    except Exception as e:
        logger.error("Unexpected error while verifying and registering merchant: %s", e)
        raise HTTPException(status_code=500, detail="Failed to verify and register merchant") from e

@router.post("/otp/get")
async def get_otps(payload: GetOtpRequest):
    """
    API endpoint to retrieve the email or SMS OTP from Redis cache.

    Args:
        payload (GetOtpRequest): The request payload containing the identifier and type.

    Returns:
        dict: The OTP data if found, or an error message if not found.
    """
    try:
        logger.info("Retrieving OTP for identifier: %s, type: %s", payload.identifier, payload.type)

        # Construct the Redis key based on the type
        redis_key = f"otp:{payload.type}:{payload.identifier}"

        # Retrieve OTP from Redis
        otp_data = await get_otp_from_cache(redis_key)
        if not otp_data:
            raise HTTPException(status_code=404, detail="OTP not found or expired")

        return {"identifier": payload.identifier, "type": payload.type, "otp_data": otp_data}

    except HTTPException as e:
        logger.error("Failed to retrieve OTP for identifier %s, type %s: %s", payload.identifier, payload.type, e.detail)
        raise e
    except Exception as e:
        logger.error("Unexpected error while retrieving OTP for identifier %s, type %s: %s", payload.identifier, payload.type, e)
        raise HTTPException(status_code=500, detail="Failed to retrieve OTP") from e

@router.post("/otp/regenerate")
async def regenerate_otp(user: MerchantRegister = Body(...)):
    """
    API endpoint to regenerate an OTP for a given email, mobile number, or both.

    Args:
        user (MerchantRegister): The Merchant object containing email and mobile details.

    Returns:
        dict: Confirmation message indicating the OTP has been regenerated.
    """
    try:
        logger.info("Regenerating OTP for Merchant with email: %s and mobile: %s", user.email, user.mobile)

        # Regenerate OTP for email & mobile
        if user.email and user.mobile:
            await generate_and_send_otp(user.email, user.mobile)       

        return {"message": "OTP successfully regenerated for email and/or mobile.", "email": user.email, "mobile": user.mobile}

    except Exception as e:
        logger.error("Failed to regenerate OTP for Merchant with email: %s and mobile: %s. Error: %s", user.email, user.mobile, e)
        raise HTTPException(status_code=500, detail="Failed to regenerate OTP") from e