import re
from datetime import datetime, timedelta, timezone

import psycopg
import pytest

from app.domains import accounts
from app.platform import db, mailer


@pytest.fixture()
def conn(fresh_db_url):
    with psycopg.connect(fresh_db_url) as c:
        db.migrate(c)
        yield c


def _issue(conn, email) -> str:
    m = mailer.LogMailer()
    accounts.request_code(conn, m, email)
    return re.search(r"\b(\d{6})\b", m.outbox[-1].body).group(1)


def test_14_01_0004_verify_creates_account_and_reports_created(conn):
    code = _issue(conn, "merchant@example.com")
    account, created = accounts.verify(conn, "merchant@example.com", code)
    assert created is True
    assert account.email == "merchant@example.com"
    assert account.id > 0
    # the account row exists exactly once (INV-2)
    n = conn.execute("SELECT count(*) FROM account WHERE email = %s", ("merchant@example.com",)).fetchone()[0]
    assert n == 1


def test_14_01_0009_returning_account_reports_not_created(conn):
    # First sign-up creates the account.
    code1 = _issue(conn, "merchant@example.com")
    a1, created1 = accounts.verify(conn, "merchant@example.com", code1)
    assert created1 is True
    # A later login resolves to the SAME account (INV-2 — email is canonical), created=False.
    code2 = _issue(conn, "Merchant@Example.com")  # different casing, same identity
    a2, created2 = accounts.verify(conn, "Merchant@Example.com", code2)
    assert created2 is False
    assert a2.id == a1.id
    n = conn.execute("SELECT count(*) FROM account").fetchone()[0]
    assert n == 1  # no duplicate account (14.01.0010)


def test_verify_consumes_the_code_single_use(conn):
    code = _issue(conn, "merchant@example.com")
    accounts.verify(conn, "merchant@example.com", code)
    # Reusing a consumed code is refused (single-use, INV-3): no live code -> CodeExpired.
    with pytest.raises(accounts.CodeExpired):
        accounts.verify(conn, "merchant@example.com", code)


def test_puc_02a_wrong_code_decrements_attempts(conn):
    _issue(conn, "merchant@example.com")
    with pytest.raises(accounts.CodeMismatch) as exc:
        accounts.verify(conn, "merchant@example.com", "000000")
    # 5 attempts allowed; one wrong -> 4 remaining (INV-3).
    assert exc.value.attempts_remaining == 4


def test_puc_02b_expired_code_is_refused(conn):
    code = _issue(conn, "merchant@example.com")
    # Force the live code to be expired.
    conn.execute(
        "UPDATE auth_code SET expires_at = %s WHERE email = %s",
        (datetime.now(timezone.utc) - timedelta(minutes=1), "merchant@example.com"),
    )
    conn.commit()
    with pytest.raises(accounts.CodeExpired):
        accounts.verify(conn, "merchant@example.com", code)


def test_inv3_attempts_exhausted_invalidates_code(conn):
    code = _issue(conn, "merchant@example.com")
    # Five wrong attempts: the 5th raises CodeExhausted and invalidates the code.
    for _ in range(4):
        with pytest.raises(accounts.CodeMismatch):
            accounts.verify(conn, "merchant@example.com", "000000")
    with pytest.raises(accounts.CodeExhausted):
        accounts.verify(conn, "merchant@example.com", "000000")
    # Even the correct code no longer works — a fresh request is required.
    with pytest.raises((accounts.CodeExpired, accounts.CodeExhausted)):
        accounts.verify(conn, "merchant@example.com", code)


def test_verify_with_no_request_is_code_expired(conn):
    with pytest.raises(accounts.CodeExpired):
        accounts.verify(conn, "stranger@example.com", "123456")


def test_get_account_loads_by_id(conn):
    code = _issue(conn, "merchant@example.com")
    account, _ = accounts.verify(conn, "merchant@example.com", code)
    loaded = accounts.get_account(conn, account.id)
    assert loaded is not None and loaded.email == "merchant@example.com"
    assert accounts.get_account(conn, 999999) is None