cleanup

backend/handler/filesystem/roms_handler.py

@@ -65,6 +65,7 @@ CHD_VERSION_LENGTH: Final = 4  # Version is a uint32
 CHD_V5_SHA1_OFFSET: Final = 84  # Combined raw+meta SHA1 offset in v5
 CHD_V5_SHA1_LENGTH: Final = 20  # SHA1 is 20 bytes
 CHD_V5_VERSION: Final = 5  # CHD v5 identifier
+CHD_MIME_TYPE: Final = "application/x-mame-chd"
 
 NON_HASHABLE_PLATFORMS = frozenset(
     (
@@ -98,6 +99,7 @@ NON_HASHABLE_PLATFORMS = frozenset(
 )
 
 FILE_READ_CHUNK_SIZE = 1024 * 8
+_MIME_DETECTOR = magic.Magic(mime=True)
 
 
 class FSRom(TypedDict):
@@ -119,8 +121,10 @@ class FileHash(TypedDict):
 
 
 def is_compressed_file(file_path: str) -> bool:
-    mime = magic.Magic(mime=True)
-    file_type = mime.from_file(file_path)
+    try:
+        file_type = _MIME_DETECTOR.from_file(file_path)
+    except magic.MagicException:
+        file_type = ""
 
     return file_type in COMPRESSED_MIME_TYPES or file_path.lower().endswith(
         tuple(COMPRESSED_FILE_EXTENSIONS)
@@ -191,7 +195,18 @@ def read_bz2_file(file_path: Path) -> Iterator[bytes]:
             yield chunk
 
 
-def extract_chd_hash(file_path: Path) -> str | None:
+def is_chd_file(file_path: Path) -> bool:
+    """Return True if the file is a CHD by extension or libmagic-detected MIME type."""
+    if file_path.suffix.lower() == ".chd":
+        return True
+
+    try:
+        return _MIME_DETECTOR.from_file(file_path) == CHD_MIME_TYPE
+    except (OSError, magic.MagicException):
+        return False
+
+
+def extract_chd_hash(file_path: Path) -> str:
     """
     Extract the embedded SHA1 hash from a CHD (Compressed Hunks of Data) v5 file header.
 
@@ -217,7 +232,7 @@ def extract_chd_hash(file_path: Path) -> str | None:
         file_path: Path to the CHD file
 
     Returns:
-        SHA1 hash as hex string, or None if file is not a valid CHD v5 file or parsing fails
+        SHA1 hash as hex string if valid
     """
     try:
         with open(file_path, "rb") as f:
@@ -229,7 +244,7 @@ def extract_chd_hash(file_path: Path) -> str | None:
                 len(header) < CHD_MIN_HEADER_LENGTH
                 or header[:CHD_SIGNATURE_LENGTH] != CHD_SIGNATURE
             ):
-                return None
+                return ""
 
             # Extract and verify version (big-endian uint32)
             version_end = CHD_VERSION_OFFSET + CHD_VERSION_LENGTH
@@ -237,16 +252,16 @@ def extract_chd_hash(file_path: Path) -> str | None:
 
             # Only support v5 CHD files
             if version != CHD_V5_VERSION:
-                return None
+                return ""
 
             # Extract combined raw+meta SHA1 from v5 header
             sha1_end = CHD_V5_SHA1_OFFSET + CHD_V5_SHA1_LENGTH
             if len(header) < sha1_end:
-                return None
+                return ""
             sha1_bytes = header[CHD_V5_SHA1_OFFSET:sha1_end]
             return sha1_bytes.hex()
     except OSError:
-        return None
+        return ""
 
 
 def category_matches(category: str, path_parts: list[str]):
@@ -388,7 +403,7 @@ class FSRomsHandler(FSHandler):
             crc_hash=file_hash["crc_hash"],
             md5_hash=file_hash["md5_hash"],
             sha1_hash=file_hash["sha1_hash"],
-            chd_sha1_hash=file_hash["chd_sha1_hash"] or None,
+            chd_sha1_hash=file_hash["chd_sha1_hash"],
         )
 
     async def get_rom_files(
@@ -417,29 +432,28 @@ class FSRomsHandler(FSHandler):
         rom_sha1_h = hashlib.sha1(usedforsecurity=False) if calculate_hashes else None
         rom_ra_h = ""
 
+        rom_dir = Path(abs_fs_path, rom.fs_name)
         # Check if rom is a multi-part rom
         if await AnyioPath(f"{abs_fs_path}/{rom.fs_name}").is_dir():
             # Calculate the RA hash if the platform has a slug that matches a known RA slug
             if calculate_hashes:
                 ra_platform = meta_ra_handler.get_platform(rom.platform_slug)
                 if ra_platform and ra_platform["ra_id"]:
-                    rom_dir = Path(abs_fs_path, rom.fs_name)
-                    # RAHasher can't process CHD files via the /* wildcard — it expects
+                    # RAHasher can't process CHD files via the /* wildcard and instead expects
                     # track files (bin/cue/etc.). For CHD-only folders, find the largest
                     # CHD and pass it directly, matching single-file CHD behaviour.
 
-                    def _list_chd_by_size() -> list[Path]:
-                        chds = [
-                            f for f in rom_dir.iterdir() if f.suffix.lower() == ".chd"
-                        ]
-                        return sorted(
+                    def _largest_chd_file() -> Path | None:
+                        chds = [f for f in rom_dir.iterdir() if is_chd_file(f)]
+                        sorted_chds = sorted(
                             chds, key=lambda f: f.stat().st_size, reverse=True
                         )
+                        return sorted_chds[0] if sorted_chds else None
 
-                    chd_files = await asyncio.to_thread(_list_chd_by_size)
+                    chd_file = await asyncio.to_thread(_largest_chd_file)
                     ra_path = (
-                        str(chd_files[0])
-                        if chd_files
+                        str(chd_file)
+                        if chd_file and chd_file.is_file()
                         else f"{abs_fs_path}/{rom.fs_name}/*"
                     )
                     rom_ra_h = await RAHasherService().calculate_hash(
@@ -494,9 +508,6 @@ class FSRomsHandler(FSHandler):
                         md5_h = hashlib.md5(usedforsecurity=False)
                         sha1_h = hashlib.sha1(usedforsecurity=False)
 
-                    chd_sha1 = ""
-                    if Path(file_name).suffix.lower() == ".chd":
-                        chd_sha1 = extract_chd_hash(Path(f_path, file_name)) or ""
                     file_hash = FileHash(
                         crc_hash=crc32_to_hex(crc_c) if crc_c != DEFAULT_CRC_C else "",
                         md5_hash=(
@@ -509,7 +520,11 @@ class FSRomsHandler(FSHandler):
                             if sha1_h.digest() != DEFAULT_SHA1_H_DIGEST
                             else ""
                         ),
-                        chd_sha1_hash=chd_sha1,
+                        chd_sha1_hash=(
+                            extract_chd_hash(rom_dir)
+                            if is_chd_file(Path(f_path, file_name))
+                            else ""
+                        ),
                     )
                 else:
                     file_hash = FileHash(
@@ -552,9 +567,6 @@ class FSRomsHandler(FSHandler):
                         f"{abs_fs_path}/{rom.fs_name}",
                     )
 
-            chd_sha1 = ""
-            if Path(rom.fs_name).suffix.lower() == ".chd":
-                chd_sha1 = extract_chd_hash(Path(abs_fs_path, rom.fs_name)) or ""
             file_hash = FileHash(
                 crc_hash=crc32_to_hex(crc_c) if crc_c != DEFAULT_CRC_C else "",
                 md5_hash=(
@@ -565,7 +577,11 @@ class FSRomsHandler(FSHandler):
                     if sha1_h.digest() != DEFAULT_SHA1_H_DIGEST
                     else ""
                 ),
-                chd_sha1_hash=chd_sha1,
+                chd_sha1_hash=(
+                    extract_chd_hash(rom_dir)
+                    if is_chd_file(Path(abs_fs_path, rom.fs_name))
+                    else ""
+                ),
             )
             rom_files.append(
                 self._build_rom_file(
@@ -617,7 +633,10 @@ class FSRomsHandler(FSHandler):
         extension = Path(file_path).suffix.lower()
         mime = magic.Magic(mime=True)
         try:
-            file_type = mime.from_file(file_path)
+            try:
+                file_type = mime.from_file(file_path)
+            except magic.MagicException:
+                file_type = ""
 
             crc_c = 0
             md5_h = hashlib.md5(usedforsecurity=False)

backend/tests/handler/filesystem/test_roms_handler.py

@@ -258,7 +258,7 @@ class TestFSRomsHandler:
                 "crc_hash": "ABCD1234",
                 "md5_hash": "def456",
                 "sha1_hash": "789ghi",
-                "chd_sha1_hash": "",
+                "chd_sha1_hash": "654321",
             }
         )
 
@@ -284,7 +284,7 @@ class TestFSRomsHandler:
                 "crc_hash": "12345678",
                 "md5_hash": "abcdef",
                 "sha1_hash": "123456",
-                "chd_sha1_hash": "",
+                "chd_sha1_hash": "654321",
             }
         )
 
@@ -842,7 +842,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is not None
+        assert result
         assert isinstance(result, str)
         assert len(result) == 40  # SHA1 hex is 40 characters
         assert result == "0123456789abcdef0123456789abcdef01234567"
@@ -859,7 +859,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_v2_rejected(self, tmp_path):
         """Test that CHD v2 files are rejected"""
@@ -873,7 +873,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_v3_rejected(self, tmp_path):
         """Test that CHD v3 files are rejected"""
@@ -887,7 +887,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_v4_rejected(self, tmp_path):
         """Test that CHD v4 files are rejected"""
@@ -901,7 +901,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_invalid_magic(self, tmp_path):
         """Test that files without CHD magic signature are rejected"""
@@ -915,7 +915,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_truncated_header(self, tmp_path):
         """Test that CHD v5 file with truncated header is rejected"""
@@ -930,7 +930,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_nonexistent_file(self, tmp_path):
         """Test that non-existent files are handled gracefully"""
@@ -938,7 +938,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(nonexistent)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_empty_file(self, tmp_path):
         """Test that empty files are rejected"""
@@ -947,7 +947,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_sha1_format(self, tmp_path):
         """Test that SHA1 hash is correctly formatted as hex"""
@@ -983,7 +983,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_multiple_different_hashes(self, tmp_path):
         """Test that different SHA1 hashes are correctly extracted"""
@@ -1011,11 +1011,11 @@ class TestExtractCHDHash:
     def test_extract_chd_hash_version_boundary_cases(self, tmp_path):
         """Test version checking at boundaries (0, 1, 4, 5, 6)"""
         test_versions = [
-            (0, None),  # Version 0 should return None
-            (1, None),  # Version 1 should return None
-            (4, None),  # Version 4 should return None
+            (0, ""),  # Version 0 should return ""
+            (1, ""),  # Version 1 should return ""
+            (4, ""),  # Version 4 should return ""
             (5, "0123456789abcdef0123456789abcdef01234567"),  # Version 5 should work
-            (6, None),  # Version 6 should return None
+            (6, ""),  # Version 6 should return ""
         ]
 
         for version, expected in test_versions:
@@ -1030,10 +1030,7 @@ class TestExtractCHDHash:
 
             result = extract_chd_hash(chd_file)
 
-            if expected is None:
-                assert result is None, f"Version {version} should return None"
-            else:
-                assert result == expected, f"Version {version} should return {expected}"
+            assert result == expected, f"Version {version} should return {expected!r}"
 
     def test_extract_chd_hash_file_too_short_for_magic(self, tmp_path):
         """Test file that's too short to even contain magic + version"""
@@ -1047,7 +1044,7 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_permission_error(self, tmp_path):
         """Test graceful handling of permission errors"""
@@ -1064,7 +1061,7 @@ class TestExtractCHDHash:
 
         try:
             result = extract_chd_hash(chd_file)
-            assert result is None
+            assert result == ""
         finally:
             # Restore permissions for cleanup
             chd_file.chmod(0o644)
@@ -1109,7 +1106,7 @@ class TestExtractCHDHash:
         # Expected SHA1 from the header at bytes 84-103 (20 bytes, as per chd.h)
         expected_sha1 = "0167fc76f9e4312e6ab48fe980d2ce5b23f775c2"
 
-        assert result is not None
+        assert result
         assert result == expected_sha1
         assert len(result) == 40
         # Verify it matches what's in the header
@@ -1136,14 +1133,14 @@ class TestExtractCHDHash:
 
         result = extract_chd_hash(chd_file)
 
-        assert result is not None
+        assert result
         assert result == "0167fc76f9e4312e6ab48fe980d2ce5b23f775c2"
         assert bytes.fromhex(result) == test_sha1
 
     def test_extract_chd_hash_off_by_one_header_sizes(self, tmp_path):
         """Test boundary conditions around minimum required header size (104 bytes)"""
         test_cases = [
-            (103, None),  # 103 bytes - not enough for SHA1 region
+            (103, ""),  # 103 bytes - not enough for SHA1 region
             (
                 104,
                 "0167fc76f9e4312e6ab48fe980d2ce5b23f775c2",
@@ -1186,7 +1183,7 @@ class TestExtractCHDHash:
         result = extract_chd_hash(chd_file)
 
         # Should return None because version is not 5
-        assert result is None
+        assert result == ""
 
     def test_extract_chd_hash_zero_sha1(self, tmp_path):
         """Test handling of all-zero SHA1 hash (edge case but valid)"""

frontend/src/components/Details/Info/FileInfo.vue

@@ -20,7 +20,7 @@ const romInfo = ref([
   { label: "Size", value: formatBytes(props.rom.fs_size_bytes) },
   { label: "SHA-1", value: props.rom.sha1_hash },
   {
-    label: "Disc SHA-1",
+    label: "CHD SHA-1",
     value: props.rom.has_simple_single_file
       ? (props.rom.files[0]?.chd_sha1_hash ?? null)
       : null,

frontend/src/components/Details/Info/FileSelectItem.vue

@@ -21,7 +21,7 @@ const fileInfo = ref([
       : null,
   },
   {
-    label: "Disc SHA-1",
+    label: "CHD SHA-1",
     value: props.item.chd_sha1_hash
       ? props.item.chd_sha1_hash.substring(0, 6) +
         "..." +