import shutil
import unittest
from pathlib import Path

from composectl import (
    build_compose_command,
    build_update_commands,
    detect_runtime,
    discover_compose_files,
    discover_stack_names,
)


class ComposeCtlTests(unittest.TestCase):
    def test_detect_runtime_returns_installed_backend(self):
        runtime = detect_runtime(preferred="docker")
        expected = "docker" if shutil.which("docker") else "podman"
        self.assertEqual(runtime, expected)

    def test_build_compose_command_uses_selected_runtime(self):
        cmd = build_compose_command(
            runtime="podman",
            compose_file=Path("media/compose.yaml"),
            project_name="media_services",
            action="up",
        )
        self.assertEqual(
            cmd,
            ["podman", "compose", "-f", "media/compose.yaml", "-p", "media_services", "up", "-d"],
        )

    def test_discover_compose_files_finds_existing_stacks(self):
        stack_files = discover_compose_files(Path("."))
        self.assertIn(Path("services/media/compose.yaml"), stack_files)

    def test_discover_stack_names_returns_inferred_stack_names(self):
        stack_names = discover_stack_names(Path("."))
        self.assertIn("media", stack_names)

    def test_build_update_commands_returns_full_stack_refresh_sequence(self):
        commands = build_update_commands(
            runtime="podman",
            compose_file=Path("services/media/compose.yaml"),
            project_name="media_services",
        )
        self.assertEqual(
            commands,
            [
                ["podman", "compose", "-f", "services/media/compose.yaml", "-p", "media_services", "pull"],
                ["podman", "compose", "-f", "services/media/compose.yaml", "-p", "media_services", "down"],
                ["podman", "compose", "-f", "services/media/compose.yaml", "-p", "media_services", "up", "-d"],
                ["podman", "image", "prune", "-f"],
            ],
        )


if __name__ == "__main__":
    unittest.main()