"""Unit tests for scripts/auto_merge.py."""

import http
from unittest.mock import MagicMock, patch

import click
import pytest
from click.testing import CliRunner

from gitea_runner_manager.config import CONVENTIONAL_RE, TASK_ID_RE
from gitea_runner_manager.exceptions import APIError
from scripts.auto_merge import extract_task_id, has_ready_to_merge_label, main, validate_pr_title


class TestRegexes:
    def test_task_id_re_matches(self) -> None:
        assert TASK_ID_RE.search("GRM-19-fix-bug")
        assert TASK_ID_RE.search("feature/GRM-42")

    def test_task_id_re_no_match(self) -> None:
        assert not TASK_ID_RE.search("feature-no-id")

    def test_conventional_re_matches(self) -> None:
        assert CONVENTIONAL_RE.match("feat: add feature")
        assert CONVENTIONAL_RE.match("fix(api): handle timeout")

    def test_conventional_re_rejects(self) -> None:
        assert not CONVENTIONAL_RE.match("random message")
        assert not CONVENTIONAL_RE.match("feat:")


class TestExtractTaskId:
    def test_extracts_from_branch(self) -> None:
        assert extract_task_id("GRM-19-fix-bug") == "GRM-19"

    def test_extracts_from_feature_branch(self) -> None:
        assert extract_task_id("feature/GRM-42-add-x") == "GRM-42"

    def test_returns_empty_when_missing(self) -> None:
        assert extract_task_id("feature-no-id") == ""


class TestValidatePrTitle:
    def test_valid_title_passes(self) -> None:
        validate_pr_title("fix: resolve timeout")

    def test_valid_title_with_scope_passes(self) -> None:
        validate_pr_title("feat(cli): add --url option")

    def test_invalid_title_raises(self) -> None:
        with pytest.raises(click.ClickException) as exc:
            validate_pr_title("random message")
        assert "conventional" in str(exc.value)


class TestHasReadyToMergeLabel:
    def test_label_present(self) -> None:
        client = MagicMock()
        client.get_pr_labels.return_value = [{"name": "bug"}, {"name": "ready-to-merge"}]
        assert has_ready_to_merge_label(client, "5") is True

    def test_label_absent(self) -> None:
        client = MagicMock()
        client.get_pr_labels.return_value = [{"name": "bug"}]
        assert has_ready_to_merge_label(client, "5") is False

    def test_no_labels(self) -> None:
        client = MagicMock()
        client.get_pr_labels.return_value = []
        assert has_ready_to_merge_label(client, "5") is False


class TestMain:
    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.auto_merge.GiteaClient")
    def test_successful_flow_with_label_arg(self, mock_client_cls: MagicMock) -> None:
        mock_client = MagicMock()
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(
            main,
            ["GRM-19-fix-bug", "fix: resolve timeout", "owner/repo", "7", "ready-to-merge"],
        )
        assert result.exit_code == 0
        assert "squash-merged" in result.output
        mock_client.merge_pr.assert_called_once_with("7", "GRM-19: fix: resolve timeout")

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.auto_merge.GiteaClient")
    def test_successful_flow_label_fallback(self, mock_client_cls: MagicMock) -> None:
        """Label not passed via arg, but PR has ready-to-merge via API."""
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(
            main,
            ["GRM-19-fix-bug", "fix: resolve timeout", "owner/repo", "7"],
        )
        assert result.exit_code == 0
        assert "squash-merged" in result.output
        mock_client.merge_pr.assert_called_once_with("7", "GRM-19: fix: resolve timeout")

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.auto_merge.GiteaClient")
    def test_wrong_label_skips_merge(self, mock_client_cls: MagicMock) -> None:
        """Label is not ready-to-merge and PR doesn't have it via API either."""
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "bug"}]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(
            main,
            ["GRM-19-fix-bug", "fix: resolve timeout", "owner/repo", "7", "bug"],
        )
        assert result.exit_code == 0
        assert "skipping" in result.output
        mock_client.merge_pr.assert_not_called()

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.auto_merge.GiteaClient")
    def test_empty_label_falls_back_to_api(self, mock_client_cls: MagicMock) -> None:
        """Gitea Actions doesn't populate label name, but API shows ready-to-merge."""
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(
            main,
            ["GRM-19-fix-bug", "fix: resolve timeout", "owner/repo", "7", ""],
        )
        assert result.exit_code == 0
        assert "squash-merged" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": ""}, clear=True)
    def test_missing_token_exits(self) -> None:
        runner = CliRunner()
        result = runner.invoke(main, ["branch", "title", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "REPO_TOKEN" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.auto_merge.GiteaClient")
    def test_missing_task_id_exits(self, mock_client_cls: MagicMock) -> None:
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["feature-no-id", "fix: bug", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "task ID" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.auto_merge.GiteaClient")
    def test_invalid_pr_title_exits(self, mock_client_cls: MagicMock) -> None:
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["GRM-19-fix", "random title", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "conventional" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.auto_merge.GiteaClient")
    def test_merge_pr_failure_raises_click(self, mock_client_cls: MagicMock) -> None:
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client.merge_pr.side_effect = APIError(http.HTTPStatus.INTERNAL_SERVER_ERROR, "server error")
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["GRM-19-fix", "fix: bug", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "HTTP" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.auto_merge.GiteaClient")
    def test_merge_pr_json_parse_failure(self, mock_client_cls: MagicMock) -> None:
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client.merge_pr.side_effect = APIError(http.HTTPStatus.BAD_GATEWAY, "bad gateway")
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["GRM-19-fix", "fix: bug", "owner/repo", "1"])
        assert result.exit_code == 1
        assert str(http.HTTPStatus.BAD_GATEWAY) in result.output