import logging
from datetime import timedelta
from typing import Optional

from django.db import transaction, models
from django.utils import timezone
from rest_framework.request import Request

from labs.models import (
    User,
    UserCreditSummary,
    UserCreditDetail,
    CreditTransaction,
    BillingUserProfile,
    BillingStripePaymentMethod,
)
from labs.billing.providers.stripe import StripeProvider
from labs.billing.utils import round_to_end_of_day
from labs.billing.consts import BILLING_ALLOWED_COUNTRIES

logger = logging.getLogger(__name__)


INITIAL_FREE_CREDITS_AMOUNT = 5
INITIAL_FREE_CREDITS_EXPIRES_IN_DAYS = 366


@transaction.atomic
def init_user_credit_record(user: User) -> None:
    """
    Initialize the credit record for a user.
    Should be called when a user is created(Sign up).

    Args:
        user: The user to initialize the credit record for

    Returns:
        None
    """
    credit_summary, created = (
        UserCreditSummary.objects.select_for_update().get_or_create(
            user=user,
        )
    )

    if not created:
        logger.info(
            f"User {user.id} already has a credit record. Skipping initialization."
        )
        return

    UserCreditDetail.objects.create(
        user=user,
        credit_type=UserCreditDetail.CreditType.PAID,
        amount=0,
    )
    UserCreditDetail.objects.create(
        user=user,
        credit_type=UserCreditDetail.CreditType.FREE,
        initial_amount=INITIAL_FREE_CREDITS_AMOUNT,
        amount=INITIAL_FREE_CREDITS_AMOUNT,
        remark="Sign up bonus",
        expires_at=round_to_end_of_day(
            timezone.now() + timedelta(days=INITIAL_FREE_CREDITS_EXPIRES_IN_DAYS)
        ),
    )
    credit_summary.free_credits = INITIAL_FREE_CREDITS_AMOUNT
    credit_summary.save()
    CreditTransaction.objects.create(
        user=user,
        transaction_type=CreditTransaction.TransactionType.BONUS,
        paid_credits=0,
        free_credits=INITIAL_FREE_CREDITS_AMOUNT,
        remark="Sign up bonus",
    )
    logger.info(f"User {user.id} credit record initialized.")


def get_balance(user: User) -> dict:
    """
    Get the balance of a user.

    Returns:
        dict: The balance of the user.
    """
    now = timezone.now()

    data = {
        "paid_credits": user.credit_summary.paid_credits,
    }

    free_credits_details = (
        UserCreditDetail.objects.filter(
            user=user,
            credit_type=UserCreditDetail.CreditType.FREE,
            expires_at__gte=now,
        )
        .order_by("expires_at", "created_at")
        .values(
            "id", "credit_type", "amount", "initial_amount", "expires_at", "created_at"
        )
    )
    data["free_credits"] = sum(detail["amount"] for detail in free_credits_details)
    data["free_credits_details"] = free_credits_details
    return data


@transaction.atomic
def update_user_credit_summary(user: User) -> None:
    """
    Update the credit summary for a user.

    Since the free credits may expire, we need to update the credit summary to ensure the credits summary is correct.
    """

    try:
        credit_summary = UserCreditSummary.objects.select_for_update().get(user=user)
    except UserCreditSummary.DoesNotExist:
        init_user_credit_record(user)
        credit_summary = UserCreditSummary.objects.select_for_update().get(user=user)

    now = timezone.now()
    free_credits_amount = (
        UserCreditDetail.objects.filter(
            user=user,
            credit_type=UserCreditDetail.CreditType.FREE,
            amount__gt=0,
            expires_at__gte=now,
        ).aggregate(total_amount=models.Sum("amount"))["total_amount"]
        or 0
    )
    credit_summary.free_credits = free_credits_amount
    credit_summary.save()
    logger.info(f"User {user.id} credit summary updated.")


def get_user_billing_profile(user: User) -> tuple[Optional[dict], list]:
    """
    Get the user billing profile for a user.

    Args:
        user: The user to get the profile for

    Returns:
        tuple[Optional[dict], list]: A tuple containing:
            - billing_details: User's billing address information or None if not set
            - stripe_payment_methods: List of user's stripe payment methods
    """
    billing_details = None
    try:
        profile = BillingUserProfile.objects.get(user=user)
        if profile.country:
            billing_details = {
                "country": profile.country,
                "city": profile.city,
                "state": profile.state,
                "postal_code": profile.postal_code,
                "line1": profile.line1,
                "line2": profile.line2,
            }
    except BillingUserProfile.DoesNotExist:
        logger.debug(f"No billing profile found for user {user.id}")

    stripe_payment_methods = BillingStripePaymentMethod.objects.filter(
        user=user
    ).values(
        "stripe_pm_id",
        "card_brand",
        "last4",
        "exp_month",
        "exp_year",
    )

    return billing_details, stripe_payment_methods