"""Unit tests for scripts/ci/post_merge.py."""

import http
import subprocess
from unittest.mock import MagicMock, patch

import click
import pytest
from click.testing import CliRunner

from devx.ci.post_merge import (
    _get_git_commit_message,
    _get_git_commit_sha,
    build_comment,
    extract_conventional_msg,
    extract_task_id,
    main,
    resolve_task_id,
)
from devx.exceptions import APIError


class TestExtractTaskId:
    def test_extracts_from_first_line(self) -> None:
        assert extract_task_id("DEVX-19: fix: resolve bug\n\nBody") == "DEVX-19"

    def test_returns_empty_when_missing(self) -> None:
        assert extract_task_id("fix: resolve bug") == ""


class TestExtractConventionalMsg:
    def test_strips_colon_prefix(self) -> None:
        """Legacy format: DEVX-N: <message>"""
        assert extract_conventional_msg("DEVX-19: fix: resolve bug") == "fix: resolve bug"

    def test_strips_space_prefix(self) -> None:
        """Current format: DEVX-N <message>"""
        assert extract_conventional_msg("DEVX-19 fix: resolve bug") == "fix: resolve bug"

    def test_returns_unchanged_without_prefix(self) -> None:
        assert extract_conventional_msg("fix: resolve bug") == "fix: resolve bug"


class TestBuildComment:
    def test_html_format(self) -> None:
        html = build_comment("DEVX-19", "fix: bug", "abc123")
        assert "<strong>DEVX-19</strong>" in html
        assert "fix: bug" in html
        assert "<code>abc123</code>" in html


class TestResolveTaskId:
    def test_found(self) -> None:
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"id": 42, "identifier": "DEVX-19"},
        ]
        assert resolve_task_id(mock_client, "DEVX-19") == 42
        mock_client.list_project_tasks.assert_called_once()

    def test_not_found_raises(self) -> None:
        """Missing Vikunja task is a fatal error — every PR must have a task."""
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = []
        with pytest.raises(click.ClickException, match="Could not find"):
            resolve_task_id(mock_client, "DEVX-99")

    def test_found_on_second_page(self) -> None:
        """Task is on page 2 when project has more than 50 tasks."""
        mock_client = MagicMock()
        page1 = [{"id": i, "identifier": f"DEVX-{i}"} for i in range(50)]
        page2 = [{"id": 100, "identifier": "DEVX-99"}]
        mock_client.list_project_tasks.side_effect = [page1, page2]
        assert resolve_task_id(mock_client, "DEVX-99") == 100
        assert mock_client.list_project_tasks.call_count == 2

    def test_stops_when_page_is_partial(self) -> None:
        """Stops paginating when a page has fewer than DEFAULT_PER_PAGE results."""
        mock_client = MagicMock()
        page1 = [{"id": i, "identifier": f"DEVX-{i}"} for i in range(10)]
        mock_client.list_project_tasks.return_value = page1
        with pytest.raises(click.ClickException, match="Could not find"):
            resolve_task_id(mock_client, "DEVX-99")
        assert mock_client.list_project_tasks.call_count == 1

    def test_http_error_propagates(self) -> None:
        mock_client = MagicMock()
        mock_client.list_project_tasks.side_effect = APIError(http.HTTPStatus.INTERNAL_SERVER_ERROR, "server error")
        with pytest.raises(APIError):
            resolve_task_id(mock_client, "DEVX-19")


class TestMain:
    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    @patch("devx.ci.post_merge.VikunjaClient")
    def test_full_flow(
        self, mock_client_cls: MagicMock, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock
    ) -> None:
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"id": 267, "identifier": "DEVX-20"},
        ]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(
            main,
            ["DEVX-20: fix: resolve bug\n\nBody", "--commit-sha", "abc123"],
        )
        assert result.exit_code == 0
        assert "updated and marked done" in result.output
        mock_client.post_comment.assert_called_once()
        mock_client.update_task.assert_called_once_with(267, done=True)

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    @patch("devx.ci.post_merge.VikunjaClient")
    def test_no_commit_sha(
        self, mock_client_cls: MagicMock, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock
    ) -> None:
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"id": 267, "identifier": "DEVX-20"},
        ]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["DEVX-20: fix: resolve bug"])
        assert result.exit_code == 0
        mock_client.post_comment.assert_called_once()
        args, _ = mock_client.post_comment.call_args
        assert "unknown" in args[1]

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": ""}, clear=True)
    def test_missing_token_exits(self, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock) -> None:
        runner = CliRunner()
        result = runner.invoke(main, ["DEVX-20: fix: bug"])
        assert result.exit_code == 1
        assert "VIKUNJA_TOKEN" in result.output

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    def test_no_task_id_non_release_fails(
        self, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock
    ) -> None:
        """Non-release commits without DEVX-N prefix should fail."""
        runner = CliRunner()
        result = runner.invoke(main, ["fix: resolve bug"])
        assert result.exit_code != 0
        assert "No task ID" in result.output

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    def test_release_commit_without_task_id_skips(
        self, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock
    ) -> None:
        """Release commits without DEVX-N prefix should skip gracefully."""
        runner = CliRunner()
        result = runner.invoke(main, ["release: v0.3.2"])
        assert result.exit_code == 0
        assert "skipping" in result.output

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    def test_revert_commit_skips(self, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock) -> None:
        """Revert commits without DEVX-N prefix should skip gracefully."""
        runner = CliRunner()
        result = runner.invoke(main, ["revert: remove v0.6.0 release"])
        assert result.exit_code == 0
        assert "Infrastructure commit" in result.output
        assert "skipping" in result.output

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    def test_merge_commit_skips(self, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock) -> None:
        """Merge commits without DEVX-N prefix should skip gracefully."""
        runner = CliRunner()
        result = runner.invoke(main, ["Merge pull request #42"])
        assert result.exit_code == 0
        assert "Infrastructure commit" in result.output

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    @patch("devx.ci.post_merge.VikunjaClient")
    def test_resolve_failure_fails(
        self, mock_client_cls: MagicMock, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock
    ) -> None:
        """Missing Vikunja task is a fatal error — every PR must have a task."""
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = []
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["DEVX-20: fix: bug"])
        assert result.exit_code != 0
        assert "Could not find" in result.output

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    @patch("devx.ci.post_merge.VikunjaClient")
    def test_post_comment_failure_fails(
        self, mock_client_cls: MagicMock, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock
    ) -> None:
        """Vikunja API errors should fail — the task was not updated."""
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"id": 267, "identifier": "DEVX-20"},
        ]
        mock_client.post_comment.side_effect = APIError(http.HTTPStatus.INTERNAL_SERVER_ERROR, "server error")
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["DEVX-20: fix: bug"])
        assert result.exit_code != 0
        assert "Vikunja API error" in result.output

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    @patch("devx.ci.post_merge.VikunjaClient")
    def test_mark_done_failure_fails(
        self, mock_client_cls: MagicMock, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock
    ) -> None:
        """Vikunja API errors should fail — the task was not updated."""
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"id": 267, "identifier": "DEVX-20"},
        ]
        mock_client.post_comment.return_value = None
        mock_client.update_task.side_effect = APIError(http.HTTPStatus.INTERNAL_SERVER_ERROR, "server error")
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["DEVX-20: fix: bug"])
        assert result.exit_code != 0
        assert "Vikunja API error" in result.output


class TestGetGitCommitMessage:
    def test_success(self) -> None:
        mock_result = subprocess.CompletedProcess(args=[], returncode=0, stdout="DEVX-20: fix: bug\n", stderr="")
        with patch("subprocess.run", return_value=mock_result):
            assert _get_git_commit_message() == "DEVX-20: fix: bug"

    def test_failure(self) -> None:
        mock_result = subprocess.CompletedProcess(args=[], returncode=1, stdout="", stderr="git error")
        with patch("subprocess.run", return_value=mock_result):
            with pytest.raises(click.ClickException, match="git log failed"):
                _get_git_commit_message()


class TestGetGitCommitSha:
    def test_success(self) -> None:
        mock_result = subprocess.CompletedProcess(args=[], returncode=0, stdout="abc123\n", stderr="")
        with patch("subprocess.run", return_value=mock_result):
            assert _get_git_commit_sha() == "abc123"

    def test_failure(self) -> None:
        mock_result = subprocess.CompletedProcess(args=[], returncode=1, stdout="", stderr="git error")
        with patch("subprocess.run", return_value=mock_result):
            with pytest.raises(click.ClickException, match="git rev-parse failed"):
                _get_git_commit_sha()


class TestFromGit:
    @patch("devx.ci.post_merge.subprocess.run")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    @patch("devx.ci.post_merge.VikunjaClient")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="abc123")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="DEVX-20: fix: bug")
    def test_from_git(
        self, mock_msg: MagicMock, mock_sha: MagicMock, mock_client_cls: MagicMock, mock_subproc: MagicMock
    ) -> None:
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"id": 267, "identifier": "DEVX-20"},
        ]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["--from-git"])
        assert result.exit_code == 0
        assert "updated and marked done" in result.output

    @patch("devx.ci.post_merge.subprocess.run")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    @patch("devx.ci.post_merge.VikunjaClient")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="abc123")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="DEVX-20: fix: bug")
    def test_from_git_with_explicit_sha(
        self, mock_msg: MagicMock, mock_sha: MagicMock, mock_client_cls: MagicMock, mock_subproc: MagicMock
    ) -> None:
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"id": 267, "identifier": "DEVX-20"},
        ]
        mock_client_cls.return_value = mock_client
        runner = CliRunner()
        result = runner.invoke(main, ["--from-git", "--commit-sha", "explicit_sha"])
        assert result.exit_code == 0

    @patch("devx.ci.post_merge.subprocess.run")
    @patch("devx.ci.post_merge._get_git_commit_message", return_value="msg")
    @patch("devx.ci.post_merge._get_git_commit_sha", return_value="sha")
    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    def test_no_msg_and_no_from_git(self, mock_msg: MagicMock, mock_sha: MagicMock, mock_subproc: MagicMock) -> None:
        runner = CliRunner()
        result = runner.invoke(main, [])
        assert result.exit_code != 0
        assert "commit_msg" in result.output


class TestGitSha:
    """Tests for the --git-sha option (race condition fix)."""

    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    @patch("devx.ci.post_merge.VikunjaClient")
    def test_git_sha_reads_commit_from_specific_sha(self, mock_client_cls: MagicMock) -> None:
        """--git-sha reads commit message from a specific SHA, not HEAD."""
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"id": 267, "identifier": "DEVX-20"},
        ]
        mock_client_cls.return_value = mock_client
        mock_result = subprocess.CompletedProcess(args=[], returncode=0, stdout="DEVX-20: fix: bug\n", stderr="")
        with patch("subprocess.run", return_value=mock_result):
            runner = CliRunner()
            result = runner.invoke(main, ["--git-sha", "abc123"])
        assert result.exit_code == 0
        assert "updated and marked done" in result.output
        mock_client.post_comment.assert_called_once()
        # Verify the SHA was passed to the comment
        args, _ = mock_client.post_comment.call_args
        assert "abc123" in args[1]

    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    def test_git_sha_failure_raises(self) -> None:
        """--git-sha with invalid SHA should raise."""
        mock_result = subprocess.CompletedProcess(args=[], returncode=1, stdout="", stderr="bad sha")
        with patch("subprocess.run", return_value=mock_result):
            runner = CliRunner()
            result = runner.invoke(main, ["--git-sha", "badsha"])
        assert result.exit_code != 0
        assert "git log failed" in result.output

    @patch.dict("os.environ", {"VIKUNJA_TOKEN": "tok"})
    @patch("devx.ci.post_merge.VikunjaClient")
    def test_git_sha_with_explicit_commit_sha(self, mock_client_cls: MagicMock) -> None:
        """--git-sha with --commit-sha uses the explicit SHA for the comment."""
        mock_client = MagicMock()
        mock_client.list_project_tasks.return_value = [
            {"id": 267, "identifier": "DEVX-20"},
        ]
        mock_client_cls.return_value = mock_client
        mock_result = subprocess.CompletedProcess(args=[], returncode=0, stdout="DEVX-20: fix: bug\n", stderr="")
        with patch("subprocess.run", return_value=mock_result):
            runner = CliRunner()
            result = runner.invoke(main, ["--git-sha", "abc123", "--commit-sha", "explicit_sha"])
        assert result.exit_code == 0
        args, _ = mock_client.post_comment.call_args
        assert "explicit_sha" in args[1]