"""Spins up a throwaway Postgres 16 container (matching production) and
applies backoffice/db/init.sql against it, per the module's testing decision
(#14): real Postgres, no mocking, so the EXCLUDE constraint and tenancy
filters are exercised for real, not asserted by inspection.
"""
import atexit
import os
import socket
import subprocess
import sys
import time
import uuid

import psycopg
import pytest

sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))

_CONTAINER = f"smb-booking-test-db-{uuid.uuid4().hex[:8]}"


def _free_port():
    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
        s.bind(("127.0.0.1", 0))
        return s.getsockname()[1]


def _wait_ready(url, timeout=30):
    deadline = time.time() + timeout
    last_err = None
    while time.time() < deadline:
        try:
            with psycopg.connect(url, connect_timeout=2):
                return
        except psycopg.OperationalError as e:
            last_err = e
            time.sleep(0.5)
    raise RuntimeError(f"test db never became ready: {last_err}")


def _start_db():
    port = _free_port()
    subprocess.run(
        ["docker", "run", "-d", "--rm", "--name", _CONTAINER,
         "-e", "POSTGRES_DB=smbcrm_test",
         "-e", "POSTGRES_USER=smbcrm",
         "-e", "POSTGRES_PASSWORD=test",
         "-p", f"127.0.0.1:{port}:5432",
         "postgres:16-alpine"],
        check=True, capture_output=True)
    atexit.register(
        lambda: subprocess.run(["docker", "stop", _CONTAINER], capture_output=True))
    url = f"postgresql://smbcrm:test@127.0.0.1:{port}/smbcrm_test"
    _wait_ready(url)
    schema_path = os.path.join(os.path.dirname(__file__), "..", "..", "db", "init.sql")
    with open(schema_path) as f:
        schema = f.read()
    with psycopg.connect(url) as conn, conn.cursor() as cur:
        cur.execute(schema)
        conn.commit()
    return url


DATABASE_URL = _start_db()
os.environ["DATABASE_URL"] = DATABASE_URL


@pytest.fixture(autouse=True)
def _clean_tables():
    with psycopg.connect(DATABASE_URL) as conn, conn.cursor() as cur:
        cur.execute(
            "TRUNCATE resources, services, bookings, users, "
            "password_reset_tokens RESTART IDENTITY CASCADE")
        conn.commit()
    yield