"""Release-note changelog extraction tests (DC-6, DC-7)."""
import importlib.util
import json
import subprocess
import sys
from pathlib import Path

import pytest


REPO_ROOT = Path(__file__).resolve().parent.parent
EXTRACTOR_PATH = REPO_ROOT / "scripts" / "extract_changelog.py"
RELEASE_REQUEST_PATH = REPO_ROOT / "scripts" / "release_request.py"
CHANGELOG_PATH = REPO_ROOT / "CHANGELOG.md"


def _extractor_module():
    spec = importlib.util.spec_from_file_location("extract_changelog", EXTRACTOR_PATH)
    assert spec and spec.loader
    module = importlib.util.module_from_spec(spec)
    sys.modules[spec.name] = module
    spec.loader.exec_module(module)
    return module


def test_extracts_the_requested_version_section_verbatim():
    extractor = _extractor_module()
    changelog = """# Changelog

## [Unreleased]

## [1.4.0] - 2026-09-10

### Added

- Show a release summary to consumers.

## [1.3.0] - 2026-09-01

### Fixed

- Preserve the observation history during upgrades.
"""
    expected = """## [1.4.0] - 2026-09-10

### Added

- Show a release summary to consumers.

"""

    assert extractor.extract_version_section(changelog, "1.4.0") == expected


def test_checked_in_changelog_keeps_unreleased_first_and_categories_limited():
    lines = CHANGELOG_PATH.read_text(encoding="utf-8").splitlines()
    unreleased = lines.index("## [Unreleased]")
    version_headings = [
        index for index, line in enumerate(lines)
        if line.startswith("## [") and line != "## [Unreleased]"
    ]
    first_version = version_headings[0] if version_headings else len(lines)
    categories = [
        line.removeprefix("### ")
        for line in lines[unreleased + 1:first_version]
        if line.startswith("### ")
    ]

    assert unreleased < first_version
    assert set(categories) <= {"Added", "Changed", "Fixed"}


def test_release_footer_verifies_the_clearsigned_checksum_asset():
    footer = (REPO_ROOT / "packaging" / "release-footer.md").read_text(
        encoding="utf-8"
    )

    assert "gpg --output SHA256SUMS --decrypt SHA256SUMS.asc" in footer
    assert "sha256sum -c SHA256SUMS" in footer


@pytest.mark.parametrize(
    ("changelog", "expected_error"),
    [
        ("# Changelog\n\n## [Unreleased]\n", "missing"),
        (
            "# Changelog\n\n## [Unreleased]\n\n## [1.4.0] - 2026-09-10\n",
            "empty",
        ),
        (
            "# Changelog\n\n## [Unreleased]\n\n## [1.4.0] - 2026-02-30\n\n- Add a note.\n",
            "malformed release date",
        ),
    ],
)
def test_fails_closed_for_missing_empty_or_malformed_sections(
    changelog, expected_error
):
    extractor = _extractor_module()

    with pytest.raises(extractor.ChangelogError, match=expected_error):
        extractor.extract_version_section(changelog, "1.4.0")


def test_command_emits_a_workflow_error_and_nonzero_status(tmp_path):
    changelog = tmp_path / "CHANGELOG.md"
    changelog.write_text("# Changelog\n\n## [Unreleased]\n", encoding="utf-8")

    result = subprocess.run(
        [sys.executable, str(EXTRACTOR_PATH), str(changelog), "1.4.0"],
        capture_output=True,
        text=True,
        check=False,
    )

    assert result.returncode != 0
    assert result.stderr.startswith("::error::")
    assert "missing" in result.stderr


def test_assembles_a_release_body_without_changing_the_section():
    extractor = _extractor_module()
    section = "## [1.4.0] - 2026-09-10\n\n### Added\n\n- Show a release summary.\n"
    footer = "## Install\n\nUse the package channel.\n"

    assert extractor.assemble_release_body(section, footer) == (
        section + "\n" + footer
    )


def test_command_can_write_the_complete_release_body(tmp_path):
    changelog = tmp_path / "CHANGELOG.md"
    changelog.write_text(
        "# Changelog\n\n## [Unreleased]\n\n## [1.4.0] - 2026-09-10\n\n"
        "### Added\n\n- Show a release summary.\n",
        encoding="utf-8",
    )
    footer = tmp_path / "footer.md"
    footer.write_text("## Install\n\nUse the package channel.\n", encoding="utf-8")

    result = subprocess.run(
        [
            sys.executable,
            str(EXTRACTOR_PATH),
            str(changelog),
            "1.4.0",
            "--footer",
            str(footer),
        ],
        capture_output=True,
        text=True,
        check=False,
    )

    assert result.returncode == 0
    assert result.stdout == (
        "## [1.4.0] - 2026-09-10\n\n### Added\n\n- Show a release summary.\n\n"
        "## Install\n\nUse the package channel.\n"
    )


def test_release_request_command_reports_create_or_patch_decisions(tmp_path):
    body = tmp_path / "release-body.md"
    body.write_text("## [1.4.0] - 2026-09-10\n", encoding="utf-8")

    create = subprocess.run(
        [
            sys.executable,
            str(RELEASE_REQUEST_PATH),
            "--version",
            "1.4.0",
            "--body-file",
            str(body),
        ],
        capture_output=True,
        text=True,
        check=False,
    )
    existing = tmp_path / "existing-release.json"
    existing.write_text('{"id": 17, "assets": []}', encoding="utf-8")
    patch = subprocess.run(
        [
            sys.executable,
            str(RELEASE_REQUEST_PATH),
            "--version",
            "1.4.0",
            "--body-file",
            str(body),
            "--existing-release",
            str(existing),
        ],
        capture_output=True,
        text=True,
        check=False,
    )

    assert create.returncode == patch.returncode == 0
    assert json.loads(create.stdout) == {
        "method": "POST",
        "path": "/releases",
        "payload": {
            "tag_name": "v1.4.0",
            "name": "v1.4.0",
            "body": "## [1.4.0] - 2026-09-10\n",
        },
    }
    assert json.loads(patch.stdout) == {
        "method": "PATCH",
        "path": "/releases/17",
        "payload": {"body": "## [1.4.0] - 2026-09-10\n"},
    }