Cai
3 days ago c3cb8625712050247ccf17b4f60238304e1faf26
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#!/usr/bin/env python3
"""Offline validator for the local-unpacked Bilibili extension projection."""
 
from __future__ import annotations
 
import argparse
import base64
import ctypes
from ctypes import wintypes
from dataclasses import asdict, dataclass
import hashlib
import json
import os
from pathlib import Path, PurePosixPath
import re
import stat
import sys
from typing import Callable, Iterable
 
 
SCHEMA = 1
PROJECT_ID = "project-info"
TASK_ID = "DEV-PROJECT-INFO-BILI-AUTHENTICATED-SESSION-DOWNLOAD-20260805-001"
SOURCE_ROOT_REL = PurePosixPath("dev/project-dev/bili_authenticated_extension")
PROJECTION_ROOT_REL = PurePosixPath("dev/project-dev/bili_authenticated_extension_unpacked")
CONTRACT_REL = PurePosixPath("dev/project-dev/bili_authenticated_extension_unpacked_contract.json")
SOURCE_ARTIFACT_MANIFEST_REL = SOURCE_ROOT_REL / "source-artifact-manifest.json"
PROJECT_MARKER_REL = PurePosixPath("mbx.project.yaml")
EXPECTED_FILES = (
    "background.js",
    "manifest.json",
    "sidepanel.css",
    "sidepanel.html",
    "sidepanel.js",
)
EXPECTED_EXTENSION_ID = "oidmclckpdmpabbfedplkbdplmfcenbb"
EXPECTED_PUBLIC_DER_SHA256 = "E83C2B2AF3CF011543FBA13FBC524D1122EEA68548F9F27B9F7A82B5D594666C"
TREE_HASH_ALGORITHM = "path-nul-bytes-nul-sha256-upper-lf-v1"
SOURCE_ARTIFACT_MANIFEST_BYTES = 3770
SOURCE_ARTIFACT_MANIFEST_SHA256 = "132B637634550A43B0EDD5E8E74C439205DE4BFECCE0A9276D8EBEF78445ECFC"
FILE_ATTRIBUTE_DIRECTORY = 0x10
FILE_ATTRIBUTE_REPARSE_POINT = 0x400
FILE_READ_ATTRIBUTES = 0x80
GENERIC_READ = 0x80000000
FILE_SHARE_READ = 0x1
FILE_SHARE_WRITE = 0x2
OPEN_EXISTING = 3
FILE_FLAG_OPEN_REPARSE_POINT = 0x00200000
FILE_FLAG_BACKUP_SEMANTICS = 0x02000000
INVALID_HANDLE_VALUE = ctypes.c_void_p(-1).value
 
 
class ValidationError(RuntimeError):
    def __init__(self, code: str, message: str) -> None:
        super().__init__(message)
        self.code = code
 
 
@dataclass(frozen=True)
class PathIdentity:
    relative_path: str
    kind: str
    volume_serial: int
    file_id: int
    attributes: int
    reparse_tag: int
    final_path: str
 
 
@dataclass(frozen=True)
class FileEvidence:
    path: str
    bytes: int
    sha256: str
 
 
class _ByHandleFileInformation(ctypes.Structure):
    _fields_ = [
        ("dwFileAttributes", wintypes.DWORD),
        ("ftCreationTime", wintypes.FILETIME),
        ("ftLastAccessTime", wintypes.FILETIME),
        ("ftLastWriteTime", wintypes.FILETIME),
        ("dwVolumeSerialNumber", wintypes.DWORD),
        ("nFileSizeHigh", wintypes.DWORD),
        ("nFileSizeLow", wintypes.DWORD),
        ("nNumberOfLinks", wintypes.DWORD),
        ("nFileIndexHigh", wintypes.DWORD),
        ("nFileIndexLow", wintypes.DWORD),
    ]
 
 
if os.name == "nt":
    _kernel32 = ctypes.WinDLL("kernel32", use_last_error=True)
    _CreateFileW = _kernel32.CreateFileW
    _CreateFileW.argtypes = [
        wintypes.LPCWSTR,
        wintypes.DWORD,
        wintypes.DWORD,
        wintypes.LPVOID,
        wintypes.DWORD,
        wintypes.DWORD,
        wintypes.HANDLE,
    ]
    _CreateFileW.restype = wintypes.HANDLE
    _GetFileInformationByHandle = _kernel32.GetFileInformationByHandle
    _GetFileInformationByHandle.argtypes = [
        wintypes.HANDLE,
        ctypes.POINTER(_ByHandleFileInformation),
    ]
    _GetFileInformationByHandle.restype = wintypes.BOOL
    _GetFinalPathNameByHandleW = _kernel32.GetFinalPathNameByHandleW
    _GetFinalPathNameByHandleW.argtypes = [
        wintypes.HANDLE,
        wintypes.LPWSTR,
        wintypes.DWORD,
        wintypes.DWORD,
    ]
    _GetFinalPathNameByHandleW.restype = wintypes.DWORD
    _CloseHandle = _kernel32.CloseHandle
    _CloseHandle.argtypes = [wintypes.HANDLE]
    _CloseHandle.restype = wintypes.BOOL
 
 
class _HandleSet:
    def __init__(self) -> None:
        self.handles: list[int] = []
 
    def add(self, handle: int) -> None:
        self.handles.append(handle)
 
    def close(self) -> None:
        while self.handles:
            _CloseHandle(self.handles.pop())
 
    def __enter__(self) -> "_HandleSet":
        return self
 
    def __exit__(self, *_: object) -> None:
        self.close()
 
 
def _strict_object(pairs: list[tuple[str, object]]) -> dict[str, object]:
    result: dict[str, object] = {}
    for key, value in pairs:
        if key in result:
            raise ValidationError("E_JSON", "Duplicate JSON key.")
        result[key] = value
    return result
 
 
def _strict_json(data: bytes) -> dict[str, object]:
    try:
        value = json.loads(data.decode("utf-8"), object_pairs_hook=_strict_object)
    except (UnicodeDecodeError, json.JSONDecodeError) as exc:
        raise ValidationError("E_JSON", "Invalid strict UTF-8 JSON.") from exc
    if not isinstance(value, dict):
        raise ValidationError("E_JSON", "JSON root must be an object.")
    return value
 
 
def _validate_project_root_text(value: str) -> Path:
    if os.name != "nt":
        raise ValidationError("E_WINDOWS_REQUIRED", "Windows is required.")
    if not re.fullmatch(r"[A-Za-z]:\\[^:*?\"<>|]+(?:\\[^:*?\"<>|]+)*", value):
        raise ValidationError("E_PROJECT_ROOT", "Project root must be an unambiguous absolute drive path.")
    if value.startswith(("\\\\", "\\\\?\\", "\\\\.\\")):
        raise ValidationError("E_PROJECT_ROOT", "UNC and device paths are forbidden.")
    components = value[3:].split("\\") if len(value) > 3 else []
    if not components or any(
        part in {"", ".", ".."} or part.endswith((" ", ".")) or ":" in part
        for part in components
    ):
        raise ValidationError("E_PROJECT_ROOT", "Ambiguous project-root components are forbidden.")
    root = Path(value)
    if root.name != PROJECT_ID:
        raise ValidationError("E_PROJECT_ROOT", "Project-root identity mismatch.")
    return root
 
 
def _native(relative: PurePosixPath) -> tuple[str, ...]:
    parts = tuple(relative.parts)
    if not parts or any(part in {"", ".", ".."} or part.endswith((" ", ".")) or ":" in part for part in parts):
        raise ValidationError("E_PATH", "Invalid fixed relative path.")
    return parts
 
 
def _join(root: Path, relative: PurePosixPath) -> Path:
    return root.joinpath(*_native(relative))
 
 
def _lstat(path: Path) -> os.stat_result:
    try:
        return os.lstat(path)
    except OSError as exc:
        raise ValidationError("E_PATH_MISSING", "Required lexical path is unavailable.") from exc
 
 
def _reparse_tag(st: os.stat_result) -> int:
    return int(getattr(st, "st_reparse_tag", 0) or 0)
 
 
def _attributes(st: os.stat_result) -> int:
    return int(getattr(st, "st_file_attributes", 0) or 0)
 
 
def _open_identity(
    path: Path,
    *,
    relative: str,
    expect_dir: bool,
    handles: _HandleSet,
) -> PathIdentity:
    st = _lstat(path)
    attrs = _attributes(st)
    tag = _reparse_tag(st)
    if attrs & FILE_ATTRIBUTE_REPARSE_POINT or tag or stat.S_ISLNK(st.st_mode):
        raise ValidationError("E_REPARSE", "Reparse paths are forbidden.")
    if expect_dir:
        if not stat.S_ISDIR(st.st_mode):
            raise ValidationError("E_PATH_KIND", "Expected directory.")
        access = FILE_READ_ATTRIBUTES
        share = FILE_SHARE_READ | FILE_SHARE_WRITE
    else:
        if not stat.S_ISREG(st.st_mode):
            raise ValidationError("E_PATH_KIND", "Expected regular file.")
        access = GENERIC_READ
        share = FILE_SHARE_READ
    handle = _CreateFileW(
        str(path),
        access,
        share,
        None,
        OPEN_EXISTING,
        FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_BACKUP_SEMANTICS,
        None,
    )
    if handle == INVALID_HANDLE_VALUE:
        raise ValidationError("E_PATH_HANDLE", "Cannot open no-follow path handle.")
    handle_value = int(handle)
    handles.add(handle_value)
    info = _ByHandleFileInformation()
    if not _GetFileInformationByHandle(handle_value, ctypes.byref(info)):
        raise ValidationError("E_PATH_HANDLE", "Cannot read path identity.")
    if info.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT:
        raise ValidationError("E_REPARSE", "Reparse handle is forbidden.")
    is_directory = bool(info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
    if is_directory != expect_dir:
        raise ValidationError("E_PATH_KIND", "Handle kind mismatch.")
    size = 512
    while True:
        buffer = ctypes.create_unicode_buffer(size)
        result = _GetFinalPathNameByHandleW(handle_value, buffer, size, 0)
        if result == 0:
            raise ValidationError("E_PATH_HANDLE", "Cannot read final path.")
        if result < size:
            final_path = buffer.value
            break
        size = result + 1
    if final_path.startswith("\\\\?\\UNC\\"):
        raise ValidationError("E_PATH_ESCAPE", "UNC final paths are forbidden.")
    if final_path.startswith("\\\\?\\"):
        final_path = final_path[4:]
    file_id = (int(info.nFileIndexHigh) << 32) | int(info.nFileIndexLow)
    return PathIdentity(
        relative_path=relative,
        kind="directory" if expect_dir else "file",
        volume_serial=int(info.dwVolumeSerialNumber),
        file_id=file_id,
        attributes=int(info.dwFileAttributes),
        reparse_tag=tag,
        final_path=os.path.normpath(final_path),
    )
 
 
def _inside(root_final: str, child_final: str) -> bool:
    root_norm = os.path.normcase(os.path.normpath(root_final))
    child_norm = os.path.normcase(os.path.normpath(child_final))
    try:
        return os.path.commonpath((root_norm, child_norm)) == root_norm
    except ValueError:
        return False
 
 
def _expected_paths(root: Path) -> list[tuple[Path, str, bool]]:
    paths: dict[str, tuple[Path, str, bool]] = {}
 
    def add(path: Path, relative: str, expect_dir: bool) -> None:
        key = os.path.normcase(os.path.normpath(str(path)))
        paths[key] = (path, relative, expect_dir)
 
    add(root, ".", True)
    add(_join(root, PROJECT_MARKER_REL), PROJECT_MARKER_REL.as_posix(), False)
    for relative in (
        SOURCE_ROOT_REL,
        PROJECTION_ROOT_REL,
        CONTRACT_REL,
        SOURCE_ARTIFACT_MANIFEST_REL,
    ):
        current = root
        current_parts: list[str] = []
        for part in _native(relative):
            current = current / part
            current_parts.append(part)
            relative_text = PurePosixPath(*current_parts).as_posix()
            is_leaf = len(current_parts) == len(relative.parts)
            expect_dir = not is_leaf or relative in {SOURCE_ROOT_REL, PROJECTION_ROOT_REL}
            add(current, relative_text, expect_dir)
    for parent in (SOURCE_ROOT_REL, PROJECTION_ROOT_REL):
        for name in EXPECTED_FILES:
            add(_join(root, parent) / name, (parent / name).as_posix(), False)
    return sorted(paths.values(), key=lambda item: (len(Path(item[0]).parts), item[1]))
 
 
def _capture(root: Path) -> tuple[dict[str, PathIdentity], dict[str, FileEvidence], dict[str, object]]:
    with _HandleSet() as handles:
        identities: dict[str, PathIdentity] = {}
        for path, relative, expect_dir in _expected_paths(root):
            identity = _open_identity(
                path,
                relative=relative,
                expect_dir=expect_dir,
                handles=handles,
            )
            identities[relative] = identity
        root_identity = identities["."]
        if root_identity.final_path != os.path.normpath(str(root)):
            raise ValidationError("E_PATH_CASE_DRIFT", "Project-root physical casing mismatch.")
        if os.path.normcase(root_identity.final_path) != os.path.normcase(os.path.normpath(str(root))):
            raise ValidationError("E_PATH_ESCAPE", "Project-root physical identity mismatch.")
        for identity in identities.values():
            if identity.volume_serial != root_identity.volume_serial or not _inside(
                root_identity.final_path, identity.final_path
            ):
                raise ValidationError("E_PATH_ESCAPE", "Path escapes the trusted physical project root.")
            expected_final = root_identity.final_path
            if identity.relative_path != ".":
                expected_final = os.path.normpath(
                    os.path.join(root_identity.final_path, *PurePosixPath(identity.relative_path).parts)
                )
            if identity.final_path != expected_final:
                raise ValidationError("E_PATH_CASE_DRIFT", "Actual NTFS path casing does not match the frozen path.")
        marker_path = _join(root, PROJECT_MARKER_REL)
        marker = marker_path.read_text(encoding="utf-8")
        if not re.search(r"(?m)^project:\s*$", marker) or not re.search(
            rf"(?m)^  id: {re.escape(PROJECT_ID)}\s*$", marker
        ):
            raise ValidationError("E_PROJECT_ROOT", "Project marker mismatch.")
        contract_path = _join(root, CONTRACT_REL)
        contract = _strict_json(contract_path.read_bytes())
        _validate_contract_shape(contract)
        source_artifact_manifest = _join(root, SOURCE_ARTIFACT_MANIFEST_REL).read_bytes()
        _validate_source_artifact_manifest(source_artifact_manifest, contract)
        source_root = _join(root, SOURCE_ROOT_REL)
        projection_root = _join(root, PROJECTION_ROOT_REL)
        _validate_projection_set(projection_root)
        source_evidence = _read_files(source_root)
        projection_evidence = _read_files(projection_root)
        _validate_evidence(contract, source_evidence, projection_evidence)
        _validate_manifest((projection_root / "manifest.json").read_bytes())
        return identities, projection_evidence, contract
 
 
def _validate_projection_set(root: Path) -> None:
    actual: list[str] = []
    try:
        with os.scandir(root) as entries:
            for entry in entries:
                if entry.name.startswith("_"):
                    raise ValidationError("E_RESERVED_NAME", "Reserved underscore path is forbidden.")
                if entry.is_symlink() or not entry.is_file(follow_symlinks=False):
                    raise ValidationError("E_PROJECTION_SET", "Projection must contain only regular files.")
                actual.append(entry.name)
    except OSError as exc:
        raise ValidationError("E_PROJECTION_SET", "Cannot enumerate projection.") from exc
    if tuple(sorted(actual)) != EXPECTED_FILES:
        raise ValidationError("E_PROJECTION_SET", "Projection exact file set mismatch.")
 
 
def _read_files(root: Path) -> dict[str, FileEvidence]:
    result: dict[str, FileEvidence] = {}
    for name in EXPECTED_FILES:
        data = (root / name).read_bytes()
        result[name] = FileEvidence(name, len(data), hashlib.sha256(data).hexdigest().upper())
    return result
 
 
def _validate_contract_shape(contract: dict[str, object]) -> None:
    expected_keys = {
        "schema",
        "task_id",
        "project_id",
        "source_root",
        "projection_root",
        "expected_extension_id",
        "public_key_der_sha256",
        "tree_hash_algorithm",
        "tree_sha256",
        "files",
    }
    if set(contract) != expected_keys:
        raise ValidationError("E_CONTRACT", "Contract key set mismatch.")
    fixed = {
        "schema": SCHEMA,
        "task_id": TASK_ID,
        "project_id": PROJECT_ID,
        "source_root": SOURCE_ROOT_REL.as_posix(),
        "projection_root": PROJECTION_ROOT_REL.as_posix(),
        "expected_extension_id": EXPECTED_EXTENSION_ID,
        "public_key_der_sha256": EXPECTED_PUBLIC_DER_SHA256,
        "tree_hash_algorithm": TREE_HASH_ALGORITHM,
    }
    if any(contract.get(key) != value for key, value in fixed.items()):
        raise ValidationError("E_CONTRACT", "Contract fixed identity mismatch.")
    files = contract.get("files")
    if not isinstance(files, list) or len(files) != len(EXPECTED_FILES):
        raise ValidationError("E_CONTRACT", "Contract file set mismatch.")
 
 
def _tree_hash(evidence: Iterable[FileEvidence]) -> str:
    payload = bytearray()
    for item in sorted(evidence, key=lambda value: value.path):
        payload.extend(item.path.encode("utf-8"))
        payload.append(0)
        payload.extend(str(item.bytes).encode("ascii"))
        payload.append(0)
        payload.extend(item.sha256.upper().encode("ascii"))
        payload.append(0x0A)
    return hashlib.sha256(payload).hexdigest().upper()
 
 
def _contract_file_evidence(contract: dict[str, object]) -> dict[str, FileEvidence]:
    files = contract["files"]
    assert isinstance(files, list)
    expected: dict[str, FileEvidence] = {}
    for raw in files:
        if not isinstance(raw, dict) or set(raw) != {"path", "bytes", "sha256"}:
            raise ValidationError("E_CONTRACT", "Contract file entry mismatch.")
        path = raw.get("path")
        size = raw.get("bytes")
        digest = raw.get("sha256")
        if (
            not isinstance(path, str)
            or path not in EXPECTED_FILES
            or isinstance(size, bool)
            or not isinstance(size, int)
            or size <= 0
            or not isinstance(digest, str)
            or not re.fullmatch(r"[0-9A-F]{64}", digest)
            or path in expected
        ):
            raise ValidationError("E_CONTRACT", "Invalid contract file entry.")
        expected[path] = FileEvidence(path, size, digest)
    if tuple(sorted(expected)) != EXPECTED_FILES:
        raise ValidationError("E_CONTRACT", "Contract file paths mismatch.")
    return expected
 
 
def _validate_source_artifact_manifest(data: bytes, contract: dict[str, object]) -> None:
    if (
        len(data) != SOURCE_ARTIFACT_MANIFEST_BYTES
        or hashlib.sha256(data).hexdigest().upper() != SOURCE_ARTIFACT_MANIFEST_SHA256
    ):
        raise ValidationError("E_SOURCE_MANIFEST", "Frozen source artifact manifest bytes mismatch.")
    source_manifest = _strict_json(data)
    files = source_manifest.get("files")
    if not isinstance(files, list):
        raise ValidationError("E_SOURCE_MANIFEST", "Source artifact manifest files are invalid.")
    expected = _contract_file_evidence(contract)
    observed: dict[str, FileEvidence] = {}
    for raw in files:
        if not isinstance(raw, dict):
            raise ValidationError("E_SOURCE_MANIFEST", "Source artifact manifest entry is invalid.")
        path = raw.get("path")
        if path not in EXPECTED_FILES:
            continue
        if set(raw) != {"path", "bytes", "sha256"} or path in observed:
            raise ValidationError("E_SOURCE_MANIFEST", "Source artifact manifest exact-five entry is invalid.")
        size = raw.get("bytes")
        digest = raw.get("sha256")
        if isinstance(size, bool) or not isinstance(size, int) or not isinstance(digest, str):
            raise ValidationError("E_SOURCE_MANIFEST", "Source artifact manifest exact-five value is invalid.")
        observed[path] = FileEvidence(path, size, digest)
    if observed != expected:
        raise ValidationError("E_SOURCE_MANIFEST", "Source artifact manifest exact-five binding mismatch.")
 
 
def _validate_evidence(
    contract: dict[str, object],
    source: dict[str, FileEvidence],
    projection: dict[str, FileEvidence],
) -> None:
    expected = _contract_file_evidence(contract)
    if source != expected or projection != expected or source != projection:
        raise ValidationError("E_BYTE_DRIFT", "Source/projection bytes are not exactly locked.")
    tree = _tree_hash(projection.values())
    if contract.get("tree_sha256") != tree:
        raise ValidationError("E_TREE_HASH", "Projection tree hash mismatch.")
 
 
def _validate_manifest(data: bytes) -> None:
    manifest = _strict_json(data)
    if (
        manifest.get("manifest_version") != 3
        or manifest.get("name") != "project-info Bilibili 完整视频入口"
        or manifest.get("version") != "1.2.25"
        or manifest.get("version_name") != "1.2.25+20260829.generic.v027"
        or manifest.get("background") != {"service_worker": "background.js", "type": "module"}
        or manifest.get("permissions") != ["alarms", "cookies", "nativeMessaging", "scripting", "storage", "tabs"]
        or manifest.get("host_permissions") != [
            "https://www.bilibili.com/*",
            "https://*.bilibili.com/*",
        ]
        or "side_panel" in manifest
        or "action" in manifest
    ):
        raise ValidationError("E_MANIFEST", "Manifest identity mismatch.")
    key = manifest.get("key")
    if not isinstance(key, str):
        raise ValidationError("E_MANIFEST", "Manifest public key is missing.")
    try:
        der = base64.b64decode(key, validate=True)
    except ValueError as exc:
        raise ValidationError("E_MANIFEST", "Manifest public key is invalid.") from exc
    digest = hashlib.sha256(der).hexdigest().upper()
    if digest != EXPECTED_PUBLIC_DER_SHA256:
        raise ValidationError("E_MANIFEST", "Manifest public key hash mismatch.")
    extension_id = "".join(chr(ord("a") + int(nibble, 16)) for nibble in digest[:32].lower())
    if extension_id != EXPECTED_EXTENSION_ID:
        raise ValidationError("E_EXTENSION_ID", "Derived extension ID mismatch.")
 
 
def _identity_key(value: PathIdentity) -> tuple[object, ...]:
    return (
        value.relative_path,
        value.kind,
        value.volume_serial,
        value.file_id,
        value.attributes,
        value.reparse_tag,
        value.final_path,
    )
 
 
def validate_project(
    project_root_text: str,
    *,
    between_passes: Callable[[], None] | None = None,
) -> dict[str, object]:
    root = _validate_project_root_text(project_root_text)
    first_identities, first_files, first_contract = _capture(root)
    if between_passes is not None:
        between_passes()
    second_identities, second_files, second_contract = _capture(root)
    if set(first_identities) != set(second_identities) or any(
        _identity_key(first_identities[key]) != _identity_key(second_identities[key])
        for key in first_identities
    ):
        raise ValidationError("E_PATH_IDENTITY_DRIFT", "Path identity changed between validation passes.")
    if first_files != second_files or first_contract != second_contract:
        raise ValidationError("E_PATH_IDENTITY_DRIFT", "Content identity changed between validation passes.")
    root_identity = second_identities["."]
    return {
        "schema": 1,
        "status": "VALIDATION_PASS_ONLY",
        "project_id": PROJECT_ID,
        "task_id": TASK_ID,
        "project_root": str(root),
        "project_root_final": root_identity.final_path,
        "project_volume_serial": root_identity.volume_serial,
        "project_file_id": root_identity.file_id,
        "source_root": SOURCE_ROOT_REL.as_posix(),
        "projection_root": PROJECTION_ROOT_REL.as_posix(),
        "file_count": len(EXPECTED_FILES),
        "tree_sha256": second_contract["tree_sha256"],
        "extension_id": EXPECTED_EXTENSION_ID,
        "source_artifact_manifest": {
            "bytes": SOURCE_ARTIFACT_MANIFEST_BYTES,
            "sha256": SOURCE_ARTIFACT_MANIFEST_SHA256,
        },
        "files": [asdict(second_files[name]) for name in EXPECTED_FILES],
        "path_identities": [asdict(second_identities[key]) for key in sorted(second_identities)],
    }
 
 
def _parser() -> argparse.ArgumentParser:
    parser = argparse.ArgumentParser(
        description="Validate the exact local-unpacked Bilibili extension projection without launching Chrome.",
    )
    parser.add_argument("--project-root", required=True, help="Exact absolute trusted project root.")
    return parser
 
 
def main(argv: list[str] | None = None) -> int:
    args = _parser().parse_args(argv)
    try:
        result = validate_project(args.project_root)
    except ValidationError as exc:
        print(json.dumps({"schema": 1, "status": "SAFETY_STOP", "error_code": exc.code}, separators=(",", ":")))
        return 3
    print(json.dumps(result, ensure_ascii=False, sort_keys=True, separators=(",", ":")))
    return 0
 
 
if __name__ == "__main__":
    raise SystemExit(main())