"""Unit tests for devx.tools.check_alert_rules."""

from __future__ import annotations

from pathlib import Path
from unittest.mock import MagicMock, patch

from click.testing import CliRunner

from devx.tools.check_alert_rules import main


class TestMain:
    def test_skip_when_promtool_not_found(self, tmp_path: Path):
        """Should exit 0 and print skip message when promtool is not on PATH."""
        with patch("shutil.which", return_value=None):
            runner = CliRunner()
            result = runner.invoke(main, ["--template-path", str(tmp_path)])
        assert result.exit_code == 0
        assert "promtool not found" in result.output

    def test_validates_rules_successfully(self, tmp_path: Path):
        """Should exit 0 when promtool reports SUCCESS."""
        (tmp_path / "alert-rules.yml.j2").write_text("groups: []")
        mock_result = MagicMock()
        mock_result.returncode = 0
        mock_result.stdout = "Checking /tmp/test.yml\n  SUCCESS: 60 rules found\n"
        mock_result.stderr = ""
        with patch("shutil.which", return_value="/usr/bin/promtool"):
            with patch("subprocess.run", return_value=mock_result):
                runner = CliRunner()
                result = runner.invoke(main, ["--template-path", str(tmp_path)])
        assert result.exit_code == 0

    def test_fails_on_promtool_error(self, tmp_path: Path):
        """Should exit non-zero when promtool reports an error."""
        (tmp_path / "alert-rules.yml.j2").write_text("groups: []")
        mock_result = MagicMock()
        mock_result.returncode = 1
        mock_result.stdout = ""
        mock_result.stderr = "Error: invalid template function 'default'\n"
        with patch("shutil.which", return_value="/usr/bin/promtool"):
            with patch("subprocess.run", return_value=mock_result):
                runner = CliRunner()
                result = runner.invoke(main, ["--template-path", str(tmp_path)])
        assert result.exit_code != 0

    def test_uses_correct_template_path(self, tmp_path: Path):
        """Should render the specified template from the given path."""
        (tmp_path / "alert-rules.yml.j2").write_text("groups: []")
        captured_args = []

        def fake_run(args, **kwargs):
            captured_args.append(args)
            mock = MagicMock()
            mock.returncode = 0
            mock.stdout = "SUCCESS"
            mock.stderr = ""
            return mock

        with patch("shutil.which", return_value="/usr/bin/promtool"):
            with patch("subprocess.run", side_effect=fake_run):
                runner = CliRunner()
                runner.invoke(main, ["--template-path", str(tmp_path)])
        assert captured_args[0][0] == "promtool"
        assert captured_args[0][1] == "check"
        assert captured_args[0][2] == "rules"

    def test_custom_template_name(self, tmp_path: Path):
        """Should render a custom template name."""
        (tmp_path / "custom-rules.yml.j2").write_text("groups: []")
        mock_result = MagicMock()
        mock_result.returncode = 0
        mock_result.stdout = "SUCCESS"
        mock_result.stderr = ""
        with patch("shutil.which", return_value="/usr/bin/promtool"):
            with patch("subprocess.run", return_value=mock_result):
                runner = CliRunner()
                result = runner.invoke(
                    main, ["--template-path", str(tmp_path), "--template-name", "custom-rules.yml.j2"]
                )
        assert result.exit_code == 0

    def test_template_vars_passed(self, tmp_path: Path):
        """Should pass template variables to the render call."""
        (tmp_path / "alert-rules.yml.j2").write_text("grafana: {{ grafana_base_url }}\ngroups: []")
        mock_result = MagicMock()
        mock_result.returncode = 0
        mock_result.stdout = "SUCCESS"
        mock_result.stderr = ""
        with patch("shutil.which", return_value="/usr/bin/promtool"):
            with patch("subprocess.run", return_value=mock_result):
                runner = CliRunner()
                result = runner.invoke(
                    main,
                    [
                        "--template-path",
                        str(tmp_path),
                        "--var",
                        "grafana_base_url=https://grafana.test.example.com",
                    ],
                )
        assert result.exit_code == 0