"""Unit tests for scripts/ci/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.ci.auto_merge import (
    PR_TITLE_RE,
    extract_conventional_msg,
    extract_task_id,
    has_approval_review,
    has_ready_to_merge_label,
    main,
    run_cmd,
    validate_pr_title,
    validate_pr_title_matches_vikunja,
    wait_for_ci,
)

CI_SUCCESS = "success"
CI_PENDING = "pending"
CI_FAILURE = "failure"


def _status(context: str, status: str, updated_at: str = "2026-01-01T00:00:00Z") -> dict[str, str]:
    return {"context": context, "status": status, "updated_at": updated_at}


def _commit(message: str) -> dict[str, dict[str, str]]:
    return {"commit": {"message": message}}


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:")

    def test_pr_title_re_matches(self) -> None:
        assert PR_TITLE_RE.match("GRM-19: Some task title")
        assert PR_TITLE_RE.match("GRM-42:  double space title")

    def test_pr_title_re_rejects(self) -> None:
        assert not PR_TITLE_RE.match("fix: resolve timeout")
        assert not PR_TITLE_RE.match("GRM-19:No space after colon")
        assert not PR_TITLE_RE.match("random message")


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("GRM-19: Some task title", "GRM-19")

    def test_valid_title_with_scope_passes(self) -> None:
        validate_pr_title("GRM-42: Add --url option", "GRM-42")

    def test_invalid_format_raises(self) -> None:
        with pytest.raises(click.ClickException) as exc:
            validate_pr_title("random message", "GRM-19")
        assert "GRM-N" in str(exc.value)

    def test_invalid_format_conventional_raises(self) -> None:
        with pytest.raises(click.ClickException) as exc:
            validate_pr_title("fix: resolve timeout", "GRM-19")
        assert "GRM-N" in str(exc.value)

    def test_task_id_mismatch_raises(self) -> None:
        with pytest.raises(click.ClickException) as exc:
            validate_pr_title("GRM-42: Some task title", "GRM-19")
        assert "mismatch" in str(exc.value)


class TestExtractConventionalMsg:
    def test_returns_newest_conventional(self) -> None:
        """Iterates in reverse — picks the newest conventional commit."""
        commits = [
            _commit("fix: resolve timeout"),
            _commit("random message"),
            _commit("feat: add thing"),
        ]
        assert extract_conventional_msg(commits) == "feat: add thing"

    def test_falls_back_to_newest_commit(self) -> None:
        commits = [
            _commit("another random"),
            _commit("random message"),
        ]
        assert extract_conventional_msg(commits) == "random message"

    def test_uses_first_line_only(self) -> None:
        commits = [_commit("fix: resolve timeout\n\nBody text here")]
        assert extract_conventional_msg(commits) == "fix: resolve timeout"

    def test_empty_commits_returns_empty(self) -> None:
        assert extract_conventional_msg([]) == ""

    def test_commit_with_scope(self) -> None:
        commits = [_commit("feat(api): new endpoint")]
        assert extract_conventional_msg(commits) == "feat(api): new endpoint"

    def test_missing_commit_key(self) -> None:
        commits = [{}]  # type: ignore[list-item]
        assert extract_conventional_msg(commits) == ""


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 TestHasApprovalReview:
    def test_has_substantive_approved(self) -> None:
        client = MagicMock()
        client.get_pr_reviews.return_value = [
            {"state": "APPROVED", "body": "All comments addressed. LGTM.", "comments": []},
            {"state": "COMMENT"},
        ]
        assert has_approval_review(client, "5") is True

    def test_has_approved_with_inline_comments(self) -> None:
        client = MagicMock()
        client.get_pr_reviews.return_value = [
            {"state": "APPROVED", "body": "", "comments": [{"body": "good"}]},
        ]
        assert has_approval_review(client, "5") is True

    def test_trivial_approved_falls_back_to_no_changes(self) -> None:
        """A bare 'LGTM' approval (< 20 chars) without comments falls back to
        checking no REQUEST_CHANGES exist (single-token workflow)."""
        client = MagicMock()
        client.get_pr_reviews.return_value = [
            {"state": "APPROVED", "body": "LGTM", "comments": []},
        ]
        assert has_approval_review(client, "5") is True

    def test_no_approved_but_no_changes_requested(self) -> None:
        """Single-token workflow: no APPROVE but no REQUEST_CHANGES either."""
        client = MagicMock()
        client.get_pr_reviews.return_value = [{"state": "COMMENT"}]
        assert has_approval_review(client, "5") is True

    def test_changes_requested_blocks_merge(self) -> None:
        """REQUEST_CHANGES blocks merge even in single-token workflow."""
        client = MagicMock()
        client.get_pr_reviews.return_value = [{"state": "REQUEST_CHANGES", "body": "Fix this"}]
        assert has_approval_review(client, "5") is False

    def test_no_reviews_allows_merge(self) -> None:
        """No reviews at all allows merge (single-token workflow fallback)."""
        client = MagicMock()
        client.get_pr_reviews.return_value = []
        assert has_approval_review(client, "5") is True


class TestValidatePrTitleMatchesVikunja:
    @patch("scripts.ci.auto_merge.get_vikunja_task_title", return_value="")
    @patch.dict("os.environ", {}, clear=True)
    def test_no_vikunja_token_skips(self, mock_get: MagicMock) -> None:
        """Should skip validation when VIKUNJA_TOKEN is not set."""
        validate_pr_title_matches_vikunja("GRM-19: Some title", "GRM-19")

    @patch("scripts.ci.auto_merge.get_vikunja_task_title", return_value="Some task title")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"}, clear=True)
    def test_matching_title_passes(self, mock_get: MagicMock) -> None:
        validate_pr_title_matches_vikunja("GRM-19: Some task title", "GRM-19")

    @patch("scripts.ci.auto_merge.get_vikunja_task_title", return_value="Some task title")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"}, clear=True)
    def test_mismatched_title_raises(self, mock_get: MagicMock) -> None:
        with pytest.raises(click.ClickException) as exc:
            validate_pr_title_matches_vikunja("GRM-19: Different title", "GRM-19")
        assert "does not match" in str(exc.value)

    @patch("scripts.ci.auto_merge.get_vikunja_task_title", return_value="")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"}, clear=True)
    def test_task_not_found_skips(self, mock_get: MagicMock) -> None:
        """Should skip validation when Vikunja task is not found."""
        validate_pr_title_matches_vikunja("GRM-19: Some title", "GRM-19")


class TestGetVikunjaTaskTitle:
    @patch.dict("os.environ", {}, clear=True)
    def test_no_token_returns_empty(self) -> None:
        from scripts.ci.auto_merge import get_vikunja_task_title

        assert get_vikunja_task_title("GRM-19") == ""

    @patch("scripts.ci.auto_merge.VikunjaClient")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"}, clear=True)
    def test_finds_task(self, mock_client_cls: MagicMock) -> None:
        from scripts.ci.auto_merge import get_vikunja_task_title

        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"identifier": "GRM-19", "title": "Some task title"},
        ]
        mock_client_cls.return_value = mock_client
        assert get_vikunja_task_title("GRM-19") == "Some task title"

    @patch("scripts.ci.auto_merge.VikunjaClient")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"}, clear=True)
    def test_task_not_found_returns_empty(self, mock_client_cls: MagicMock) -> None:
        from scripts.ci.auto_merge import get_vikunja_task_title

        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"identifier": "GRM-20", "title": "Other task"},
        ]
        mock_client_cls.return_value = mock_client
        assert get_vikunja_task_title("GRM-19") == ""

    @patch("scripts.ci.auto_merge.VikunjaClient")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"}, clear=True)
    def test_paginates_to_find_task(self, mock_client_cls: MagicMock) -> None:
        from scripts.ci.auto_merge import get_vikunja_task_title

        mock_client = MagicMock()
        # First page: full page of 50 tasks, no match; second page: match
        page1 = [{"identifier": f"GRM-{i}", "title": f"task {i}"} for i in range(50)]
        page2 = [{"identifier": "GRM-99", "title": "Found task"}]
        mock_client.list_project_tasks.side_effect = [page1, page2]
        mock_client_cls.return_value = mock_client
        assert get_vikunja_task_title("GRM-99") == "Found task"

    @patch("scripts.ci.auto_merge.VikunjaClient")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"}, clear=True)
    def test_empty_pages_returns_empty(self, mock_client_cls: MagicMock) -> None:
        from scripts.ci.auto_merge import get_vikunja_task_title

        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = []
        mock_client_cls.return_value = mock_client
        assert get_vikunja_task_title("GRM-19") == ""


class TestWaitForCi:
    def test_all_pass_immediately(self) -> None:
        client = MagicMock()
        client.get_commit_status.return_value = [
            _status("CI / quality (pull_request)", CI_SUCCESS),
            _status("CI / molecule-tests (0) (pull_request)", CI_SUCCESS),
        ]
        assert wait_for_ci(client, "abc123", max_wait=10) is True

    def test_waits_then_passes(self) -> None:
        client = MagicMock()
        client.get_commit_status.side_effect = [
            [_status("CI / quality (pull_request)", CI_PENDING)],
            [_status("CI / quality (pull_request)", CI_SUCCESS)],
        ]
        with patch("scripts.ci.auto_merge.time.sleep"):
            assert wait_for_ci(client, "abc123", max_wait=10, poll_interval=5) is True

    def test_fails_on_failed_check(self) -> None:
        client = MagicMock()
        client.get_commit_status.return_value = [
            _status("CI / quality (pull_request)", CI_SUCCESS),
            _status("CI / molecule-tests (0) (pull_request)", CI_FAILURE),
        ]
        assert wait_for_ci(client, "abc123", max_wait=10) is False

    def test_times_out(self) -> None:
        client = MagicMock()
        client.get_commit_status.return_value = [
            _status("CI / quality (pull_request)", CI_PENDING),
        ]
        with patch("scripts.ci.auto_merge.time.sleep"):
            assert wait_for_ci(client, "abc123", max_wait=5) is False

    def test_no_statuses_waits(self) -> None:
        client = MagicMock()
        client.get_commit_status.side_effect = [
            [],
            [_status("CI / quality (pull_request)", CI_SUCCESS)],
        ]
        with patch("scripts.ci.auto_merge.time.sleep"):
            assert wait_for_ci(client, "abc123", max_wait=10, poll_interval=5) is True

    def test_ignores_non_ci_contexts(self) -> None:
        client = MagicMock()
        client.get_commit_status.return_value = [
            _status("Auto-merge / merge (pull_request)", CI_PENDING),
            _status("CI / quality (pull_request)", CI_SUCCESS),
        ]
        assert wait_for_ci(client, "abc123", max_wait=10) is True

    def test_deduplicates_by_latest(self) -> None:
        """Combined endpoint returns one entry per context; if multiple
        entries appear, the last one wins (dict comprehension)."""
        client = MagicMock()
        client.get_commit_status.return_value = [
            _status("CI / quality (pull_request)", CI_PENDING, "2026-01-01T00:00:00Z"),
            _status("CI / quality (pull_request)", CI_SUCCESS, "2026-01-01T00:01:00Z"),
        ]
        assert wait_for_ci(client, "abc123", max_wait=10) is True

    def test_skipped_jobs_count_as_passing(self) -> None:
        """Conditional jobs that are skipped should not block merge."""
        client = MagicMock()
        client.get_commit_status.return_value = [
            _status("CI / quality (pull_request)", CI_SUCCESS),
            _status("CI / badges (pull_request)", "skipped"),
            _status("CI / molecule-tests (pull_request)", "skipped"),
            _status("CI / discover-runners (pull_request)", "skipped"),
        ]
        assert wait_for_ci(client, "abc123", max_wait=10) is True

    def test_only_non_ci_contexts_waits_then_ci_appears(self) -> None:
        client = MagicMock()
        client.get_commit_status.side_effect = [
            [_status("Auto-merge / merge (pull_request)", CI_PENDING)],
            [_status("CI / quality (pull_request)", CI_SUCCESS)],
        ]
        with patch("scripts.ci.auto_merge.time.sleep"):
            assert wait_for_ci(client, "abc123", max_wait=10, poll_interval=5) is True


def _mock_pr(sha: str = "abc123def456") -> dict[str, object]:
    return {"head": {"sha": sha}}


def _mock_ci_passing() -> list[dict[str, str]]:
    return [_status("CI / quality (pull_request)", CI_SUCCESS)]


def _mock_commits() -> list[dict[str, dict[str, str]]]:
    return [_commit("fix: resolve timeout")]


class TestMain:
    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_successful_flow_with_label_arg(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: MagicMock
    ) -> None:
        mock_client = MagicMock()
        mock_client_cls.return_value = mock_client
        mock_client.get_pr.return_value = _mock_pr()
        mock_client.get_commit_status.return_value = _mock_ci_passing()
        mock_client.get_pr_commits.return_value = _mock_commits()
        runner = CliRunner()
        result = runner.invoke(
            main,
            ["GRM-19-fix-bug", "GRM-19: Some task title", "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.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_successful_flow_label_fallback(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: 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.get_pr.return_value = _mock_pr()
        mock_client.get_commit_status.return_value = _mock_ci_passing()
        mock_client.get_pr_commits.return_value = _mock_commits()
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(
            main,
            ["GRM-19-fix-bug", "GRM-19: Some task title", "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.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_wrong_label_skips_merge(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: 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", "GRM-19: Some task title", "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.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_empty_label_falls_back_to_api(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: 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.get_pr.return_value = _mock_pr()
        mock_client.get_commit_status.return_value = _mock_ci_passing()
        mock_client.get_pr_commits.return_value = _mock_commits()
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(
            main,
            ["GRM-19-fix-bug", "GRM-19: Some task title", "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.ci.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", "GRM-19: bug", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "task ID" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.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 "GRM-N" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_pr_title_task_id_mismatch_exits(self, mock_client_cls: MagicMock) -> None:
        """PR title has a different task ID than the branch."""
        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", "GRM-42: Some task title", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "mismatch" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=False)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_no_approval_review_blocks_merge(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: MagicMock
    ) -> None:
        """No APPROVE review — merge should be blocked."""
        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", "GRM-19: Some task title", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "APPROVE review" in result.output
        mock_client.merge_pr.assert_not_called()

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_empty_commits_exits(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: MagicMock
    ) -> None:
        """PR has no commits — cannot extract conventional message."""
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client.get_pr.return_value = _mock_pr()
        mock_client.get_commit_status.return_value = _mock_ci_passing()
        mock_client.get_pr_commits.return_value = []
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["GRM-19-fix", "GRM-19: Some task title", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "conventional commit" in result.output
        mock_client.merge_pr.assert_not_called()

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_merge_pr_failure_raises_click(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: MagicMock
    ) -> None:
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client.get_pr.return_value = _mock_pr()
        mock_client.get_commit_status.return_value = _mock_ci_passing()
        mock_client.get_pr_commits.return_value = _mock_commits()
        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", "GRM-19: Some task title", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "HTTP" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_merge_pr_json_parse_failure(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: MagicMock
    ) -> None:
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client.get_pr.return_value = _mock_pr()
        mock_client.get_commit_status.return_value = _mock_ci_passing()
        mock_client.get_pr_commits.return_value = _mock_commits()
        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", "GRM-19: Some task title", "owner/repo", "1"])
        assert result.exit_code == 1
        assert str(http.HTTPStatus.BAD_GATEWAY) in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_ci_failure_blocks_merge(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: MagicMock
    ) -> None:
        """CI checks fail — merge should not be attempted."""
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client.get_pr.return_value = _mock_pr()
        mock_client.get_commit_status.return_value = [
            _status("CI / quality (pull_request)", CI_FAILURE),
        ]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["GRM-19-fix", "GRM-19: Some task title", "owner/repo", "1"])
        assert result.exit_code == 1
        assert "CI checks did not pass" in result.output
        mock_client.merge_pr.assert_not_called()

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_no_sha_proceeds_without_wait(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: MagicMock
    ) -> None:
        """PR head SHA missing — should proceed without waiting."""
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client.get_pr.return_value = {"head": {}}
        mock_client.get_pr_commits.return_value = _mock_commits()
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["GRM-19-fix", "GRM-19: Some task title", "owner/repo", "1"])
        assert result.exit_code == 0
        assert "squash-merged" in result.output

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_merge_405_behind_retries(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: MagicMock
    ) -> None:
        """405 'behind' error should trigger rebase and retry."""
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client.get_pr.return_value = _mock_pr()
        mock_client.get_commit_status.return_value = _mock_ci_passing()
        mock_client.get_pr_commits.return_value = _mock_commits()
        # First merge_pr raises 405 "behind", second succeeds
        mock_client.merge_pr.side_effect = [
            APIError(http.HTTPStatus.METHOD_NOT_ALLOWED, "head branch is behind base"),
            None,
        ]
        mock_client_cls.return_value = mock_client
        with patch("scripts.ci.auto_merge.run_cmd") as mock_run_cmd:
            mock_run_cmd.return_value = MagicMock(returncode=0, stdout="", stderr="")
            runner = CliRunner()
            result = runner.invoke(main, ["GRM-19-fix", "GRM-19: Some task title", "owner/repo", "1"])
            assert result.exit_code == 0
            assert "Rebased" in result.output or "rebase" in result.output.lower()
            assert mock_client.merge_pr.call_count == 2

    @patch.dict("os.environ", {"REPO_TOKEN": "tok"})
    @patch("scripts.ci.auto_merge.validate_pr_title_matches_vikunja")
    @patch("scripts.ci.auto_merge.has_approval_review", return_value=True)
    @patch("scripts.ci.auto_merge.GiteaClient")
    def test_merge_405_behind_rebase_fails(
        self, mock_client_cls: MagicMock, mock_approval: MagicMock, mock_vikunja: MagicMock
    ) -> None:
        """405 'behind' with rebase failure should raise ClickException."""
        mock_client = MagicMock()
        mock_client.get_pr_labels.return_value = [{"name": "ready-to-merge"}]
        mock_client.get_pr.return_value = _mock_pr()
        mock_client.get_commit_status.return_value = _mock_ci_passing()
        mock_client.get_pr_commits.return_value = _mock_commits()
        mock_client.merge_pr.side_effect = APIError(http.HTTPStatus.METHOD_NOT_ALLOWED, "head branch is behind base")
        mock_client_cls.return_value = mock_client
        with patch("scripts.ci.auto_merge.run_cmd") as mock_run_cmd:
            mock_run_cmd.side_effect = click.ClickException("rebase failed")
            runner = CliRunner()
            result = runner.invoke(main, ["GRM-19-fix", "GRM-19: Some task title", "owner/repo", "1"])
            assert result.exit_code == 1
            assert "rebase" in result.output.lower() or "retry" in result.output.lower()

    def test_run_cmd_success(self) -> None:
        """run_cmd should return CompletedProcess on success."""
        with patch("scripts.ci.auto_merge.subprocess.run") as mock_run:
            mock_run.return_value = MagicMock(returncode=0, stdout="ok", stderr="")
            result = run_cmd(["echo", "ok"])
            assert result.returncode == 0

    def test_run_cmd_failure_raises(self) -> None:
        """run_cmd should raise ClickException on non-zero exit."""
        with patch("scripts.ci.auto_merge.subprocess.run") as mock_run:
            mock_run.return_value = MagicMock(returncode=1, stdout="", stderr="error")
            with pytest.raises(click.ClickException):
                run_cmd(["false"])