from datetime import date

import pytest
from hypothesis import HealthCheck, given, settings
from hypothesis import strategies as st
from sqlalchemy.orm import Session

from app.errors import AppError
from app.identity.models import User
from app.ledger.models import Posting
from app.ledger.service import (
    account_balance,
    create_account,
    create_expense,
    create_income,
    create_refund,
    create_transfer,
    get_account,
)
from app.spaces.service import create_space


def seed(db: Session):
    user = User(email="owner@example.test", password_hash="unused-in-domain-tests")
    db.add(user)
    db.flush()
    space = create_space(db, user=user, name="Personal")
    return user, space


@given(amount=st.integers(min_value=1, max_value=10**12))
@settings(suppress_health_check=[HealthCheck.function_scoped_fixture])
def test_transfer_postings_conserve_money(db: Session, amount: int) -> None:
    db.rollback()
    user, space = seed(db)
    source = create_account(
        db,
        space_id=space.id,
        user=user,
        name="Debit",
        kind="debit",
        opened_on=date(2026, 1, 1),
        opening_amount_kopecks=amount,
    )
    target = create_account(
        db,
        space_id=space.id,
        user=user,
        name="Cash",
        kind="cash",
        opened_on=date(2026, 1, 1),
    )
    operation = create_transfer(
        db,
        space_id=space.id,
        user=user,
        source_account_id=source.id,
        target_account_id=target.id,
        amount_kopecks=amount,
        occurred_on=date(2026, 1, 2),
    )
    db.flush()
    postings = db.query(Posting).filter_by(operation_id=operation.id).all()
    assert len(postings) == 2
    assert sum(item.amount_kopecks for item in postings) == 0
    assert account_balance(db, source) == 0
    assert account_balance(db, target) == amount
    db.rollback()


def test_credit_expense_is_negative_balance_and_refund_is_capped(db: Session) -> None:
    user, space = seed(db)
    card = create_account(
        db,
        space_id=space.id,
        user=user,
        name="Credit",
        kind="credit",
        opened_on=date(2026, 2, 1),
    )
    expense = create_expense(
        db,
        space_id=space.id,
        user=user,
        account_id=card.id,
        amount_kopecks=12_345,
        occurred_on=date(2026, 2, 2),
    )
    assert account_balance(db, card) == -12_345
    create_refund(
        db,
        space_id=space.id,
        user=user,
        parent_operation_id=expense.id,
        amount_kopecks=2_345,
        occurred_on=date(2026, 2, 3),
    )
    assert account_balance(db, card) == -10_000
    with pytest.raises(AppError, match="Refund exceeds"):
        create_refund(
            db,
            space_id=space.id,
            user=user,
            parent_operation_id=expense.id,
            amount_kopecks=10_001,
            occurred_on=date(2026, 2, 4),
        )


def test_cross_space_lookup_fails_closed(db: Session) -> None:
    user, first = seed(db)
    other = create_space(db, user=user, name="Other")
    account = create_account(
        db,
        space_id=first.id,
        user=user,
        name="Cash",
        kind="cash",
        opened_on=date(2026, 1, 1),
    )
    with pytest.raises(AppError) as exc:
        get_account(db, space_id=other.id, account_id=account.id)
    assert exc.value.code == "LEDGER_ACCOUNT_NOT_FOUND"


def test_idempotency_key_prevents_duplicate_income(db: Session) -> None:
    user, space = seed(db)
    account = create_account(
        db,
        space_id=space.id,
        user=user,
        name="Debit",
        kind="debit",
        opened_on=date(2026, 1, 1),
    )
    first = create_income(
        db,
        space_id=space.id,
        user=user,
        account_id=account.id,
        amount_kopecks=50_000,
        occurred_on=date(2026, 1, 5),
        request_key="retry-1",
    )
    second = create_income(
        db,
        space_id=space.id,
        user=user,
        account_id=account.id,
        amount_kopecks=50_000,
        occurred_on=date(2026, 1, 5),
        request_key="retry-1",
    )
    assert first.id == second.id
    assert account_balance(db, account) == 50_000