#!/usr/bin/env python3
"""Validate the version and checked-in artifacts for a LinkLog release."""

import hashlib
import json
import re
import sys
import zipfile
from pathlib import Path


ROOT = Path(__file__).resolve().parents[2]
VERSION_FILE = ROOT / 'frontend' / 'version.json'
SIGNED_DIR = ROOT / 'XPI' / 'signed'
MANIFEST_PATH = ROOT / 'webextension' / 'manifest.json'
UPDATES_PATH = ROOT / 'webextension' / 'updates.json'
ABOUT_TEMPLATE_PATH = ROOT / 'frontend' / 'templates' / 'about.html'
RAW_BASE_URL = 'https://git.kolkman.org/olaf/Link-Log/raw/branch/main'
VERSION_RE = re.compile(r'\d+\.\d+\.\d+')


def fail(message: str) -> None:
    raise SystemExit(f'release validation failed: {message}')


def version_key(version: str) -> tuple[int, int, int]:
    return tuple(int(part) for part in version.split('.'))


def find_latest_signed_xpi() -> tuple[str, Path]:
    candidates = []
    for xpi_path in SIGNED_DIR.glob('LinkLog-*.xpi'):
        match = re.fullmatch(r'LinkLog-(\d+\.\d+\.\d+)\.xpi', xpi_path.name)
        if match:
            candidates.append((match.group(1), xpi_path))
    if not candidates:
        fail(f'no signed plugin artifacts found in {SIGNED_DIR.relative_to(ROOT)}')
    return max(candidates, key=lambda candidate: version_key(candidate[0]))


def validate_self_update(source_manifest: dict, extension_version: str, xpi_path: Path) -> None:
    gecko_settings = source_manifest.get('browser_specific_settings', {}).get('gecko', {})
    addon_id = gecko_settings.get('id')
    strict_min_version = gecko_settings.get('strict_min_version')
    if not addon_id:
        fail('webextension/manifest.json is missing browser_specific_settings.gecko.id')

    updates_data = json.loads(UPDATES_PATH.read_text())
    addon_entry = updates_data.get('addons', {}).get(addon_id)
    if not addon_entry:
        fail(f'{UPDATES_PATH.relative_to(ROOT)} has no entry for add-on id {addon_id!r}')

    entry = next((u for u in addon_entry.get('updates', []) if u.get('version') == extension_version), None)
    if entry is None:
        fail(
            f'{UPDATES_PATH.relative_to(ROOT)} has no update entry for version {extension_version!r}; '
            'add one alongside the signed XPI so the self-update mechanism can find it'
        )

    expected_link = f'{RAW_BASE_URL}/{xpi_path.relative_to(ROOT).as_posix()}'
    if entry.get('update_link') != expected_link:
        fail(
            f'{UPDATES_PATH.relative_to(ROOT)} update_link {entry.get("update_link")!r} does not match '
            f'the expected raw signed XPI URL {expected_link!r}'
        )

    with xpi_path.open('rb') as xpi_file:
        expected_hash = f'sha256:{hashlib.file_digest(xpi_file, "sha256").hexdigest()}'
    if entry.get('update_hash') != expected_hash:
        fail(
            f'{UPDATES_PATH.relative_to(ROOT)} update_hash {entry.get("update_hash")!r} does not match '
            f'the SHA-256 hash of {xpi_path.relative_to(ROOT)}'
        )

    entry_min_version = entry.get('applications', {}).get('gecko', {}).get('strict_min_version')
    if entry_min_version != strict_min_version:
        fail(
            f'{UPDATES_PATH.relative_to(ROOT)} applications.gecko.strict_min_version {entry_min_version!r} '
            f'does not match webextension/manifest.json strict_min_version {strict_min_version!r}'
        )


def validate_about_plugin_link(xpi_path: Path) -> None:
    expected_link = f'{RAW_BASE_URL}/{xpi_path.relative_to(ROOT).as_posix()}'
    if expected_link not in ABOUT_TEMPLATE_PATH.read_text():
        fail(
            f'{ABOUT_TEMPLATE_PATH.relative_to(ROOT)} does not link to the latest signed XPI '
            f'{xpi_path.relative_to(ROOT)}'
        )


def main() -> None:
    version_data = json.loads(VERSION_FILE.read_text())
    backend_version = version_data.get('version')
    if not backend_version:
        fail(f'version could not be found in {VERSION_FILE.relative_to(ROOT)}')
    if not VERSION_RE.fullmatch(backend_version):
        fail(f'backend version {backend_version} is not a valid three-part version')

    extension_version, xpi_path = find_latest_signed_xpi()
    source_manifest = json.loads(MANIFEST_PATH.read_text())
    if source_manifest.get('version') != extension_version:
        fail(
            f'webextension/manifest.json version {source_manifest.get("version")!r} does not match '
            f'the latest signed XPI version {extension_version!r}'
        )
    with zipfile.ZipFile(xpi_path) as archive:
        try:
            packaged_manifest = json.loads(archive.read('manifest.json'))
        except KeyError:
            fail('signed XPI does not contain manifest.json')
        if packaged_manifest.get('version') != extension_version:
            fail('signed XPI manifest version does not match its filename')
        gecko_settings = packaged_manifest.get('browser_specific_settings', {}).get('gecko', {})
        data_permissions = gecko_settings.get('data_collection_permissions')
        if data_permissions != {'required': ['websiteActivity'], 'optional': []}:
            fail('Firefox data_collection_permissions must require websiteActivity and have no optional categories')
        if archive.testzip() is not None:
            fail('signed XPI contains a corrupt member')

    validate_self_update(source_manifest, extension_version, xpi_path)
    validate_about_plugin_link(xpi_path)

    signed_xpi = xpi_path.relative_to(ROOT)
    if len(sys.argv) == 3 and sys.argv[1] == '--github-output':
        with Path(sys.argv[2]).open('a') as output:
            print(f'backend_version={backend_version}', file=output)
            print(f'plugin_version={extension_version}', file=output)
            print(f'signed_xpi={signed_xpi}', file=output)
    elif len(sys.argv) != 1:
        fail('usage: validate_release.py [--github-output <path>]')

    print(f'validated LinkLog backend release {backend_version}')
    print(f'plugin_version={extension_version}')
    print(f'signed_xpi={signed_xpi}')


if __name__ == '__main__':
    main()