import os
import subprocess

import pytest

from core.backup import (
    DatabaseSnapshot,
    DatabaseTarget,
    _read_snapshot,
    run_synthetic_restore_verification,
)


def test_backup_configuration_is_allow_gated(settings):
    assert settings.BACKUP_ROOT == "/app/backups"
    if not os.environ.get("BACKUP_SOURCE_HOST"):
        assert settings.BACKUP_VERIFY_ALLOWED is False


def test_application_image_installs_matching_postgresql_client():
    result = subprocess.run(
        ["pg_dump", "--version"], check=True, capture_output=True, text=True
    )

    assert result.stdout.startswith("pg_dump (PostgreSQL) 17.")


@pytest.mark.skipif(
    not all(
        os.environ.get(name)
        for name in (
            "BACKUP_SOURCE_HOST",
            "BACKUP_SOURCE_NAME",
            "BACKUP_SOURCE_USER",
            "BACKUP_SOURCE_PASSWORD",
        )
    ),
    reason="requires the backup profile's disposable databases",
)
def test_synthetic_restore_is_repeatable_and_leaves_both_databases_empty(
    settings, django_db_blocker
):
    with django_db_blocker.unblock():
        first = run_synthetic_restore_verification()
        second = run_synthetic_restore_verification()
        source = DatabaseTarget(
            host=os.environ["BACKUP_SOURCE_HOST"],
            port=os.environ.get("BACKUP_SOURCE_PORT", "5432"),
            name=os.environ["BACKUP_SOURCE_NAME"],
            user=os.environ["BACKUP_SOURCE_USER"],
            password=os.environ["BACKUP_SOURCE_PASSWORD"],
        )
        target = DatabaseTarget.from_default(settings.DATABASES["default"])
        empty = DatabaseSnapshot(migrations=(), row_counts={})
        assert first.row_counts == second.row_counts
        assert _read_snapshot(source) == empty
        assert _read_snapshot(target) == empty