import sys
import pytest
import testinfra
import os
import shutil
import subprocess
import textwrap

from pathlib import Path
THIS_COOKBOOK_DIR = Path(__file__).parent.parent
COOKBOOKS_DIR = THIS_COOKBOOK_DIR.parent
TOP_LEVEL_DIR = COOKBOOKS_DIR.parent
THIS_COOKBOOK_NAME = THIS_COOKBOOK_DIR.name

# Add directories to the path so we can import Python modules from the top level "tests" directory and current directory.
sys.path.insert(0, str(Path(__file__).parent))
sys.path.insert(0, str(TOP_LEVEL_DIR / "tests"))
import helpers  # noqa: E402
from fcos_vm import FCOSVirtualMachine, ensure_fcos_ign  # noqa: E402

# Major version of PostgreSQL to install by default on a fresh VM boot.
PG_MAJOR_DEFAULT = 18

# PostgreSQL VM are kept for the duration of a test module, backed with a persistent Virtiofs directory.
@pytest.fixture(scope="module")
def fcos_vm(
    request,
    keep_vm: bool,
    test_ssh_key: Path,
    test_ssh_pubkey: str,
    virtiofs_dirs: list[tuple[Path, str]],
    tmp_path_factory: pytest.TempPathFactory,
) -> FCOSVirtualMachine:
    """Running CoreOS VM with Quadlets installed.

    With --keep-vm the VM is reused across runs: it is created only if it
    does not already exist and is never destroyed on teardown.
    """
    module_name = request.module.__name__.split(".")[-1].replace("test_", "").replace("_", "-")
    vm = FCOSVirtualMachine(
        cookbook_name=THIS_COOKBOOK_NAME,
        instance_name=module_name,
        keep=keep_vm,
        virtiofs_dirs=virtiofs_dirs,
    )

    if not (keep_vm and vm.exists()):
        fcos_ign = ensure_fcos_ign(THIS_COOKBOOK_DIR)
        vm.ignition.ignition_files.append(fcos_ign)
        vm.ignition.extra_files.update({
            "/etc/quadlets/postgresql/config.env": (
                textwrap.dedent(f"""
                    # This file is generated by conftest.py for testing purposes.
                    POSTGRES_USER=postgres
                    POSTGRES_PASSWORD=postgres
                    POSTGRES_DB=postgres
                    POSTGRES_HOST_AUTH_METHOD=scram-sha-256
                    POSTGRES_INITDB_ARGS=--auth-host=scram-sha-256
                    POSTGRES_ARGS=-h 127.0.0.1
                    PGPORT=5432
                    PG_MAJOR={PG_MAJOR_DEFAULT}
                    POSTGRES_BACKUP_RETENTION=7
                """),
                0,
                0,
                0o600,
            ),
        })
        vm.ignition.ssh_key = test_ssh_pubkey
        vm.create()

    vm.wait_ssh(ssh_key=test_ssh_key, timeout=300)

    yield vm # <-- tests run here with access to the VM instance

    if not keep_vm:
        vm.destroy()

"""
Verify that the postgresql Quadlet correctly restores a database from a backup.
"""
class TestPostgresqlQuadletRestore(helpers.TestPostgresqlQuadlet):
    expected_pg_major = PG_MAJOR_DEFAULT

    def test_data_is_still_there_after_restore(self, fcos_host):
        """Data created before the restore must still be there after the restore."""
        # Check that the old data is still there after the restore
        output = self._run_sql(fcos_host, "SELECT datname FROM pg_database WHERE datname = 'upgrade_path_db'")
        assert output == "upgrade_path_db", f"Unexpected output from SQL query: {output}"
        output = self._run_sql(fcos_host, "SELECT datname FROM pg_database WHERE datname = 'testdb'")
        assert output == "testdb", f"Unexpected output from SQL query: {output}"
        result = fcos_host.run(
            "podman exec postgresql-server psql -U test -d testdb --csv -t -c %s", "SELECT 1 AS probe"
        )
        assert result.exit_status == 0, f"SQL query failed with exit code {result.exit_status}: {result.stderr}"
        
        # Check that the upgrade_path table contains the initial postgresql version (14)
        output = self._run_sql(fcos_host, "SELECT version FROM upgrade_path ORDER BY version ASC LIMIT 1", database="upgrade_path_db")
        assert output.startswith("14."), f"Unexpected output from SQL query: {output}"