Add working crate parser and filesystem scanner

serato_doctor/crate_parser.py

@@ -0,0 +1,47 @@
+from pathlib import Path
+import re
+
+from serato_doctor.models import TrackReference
+
+AUDIO_EXTS = "mp3|m4a|wav|aif|aiff|flac|MP3|M4A|WAV|AIF|AIFF|FLAC"
+
+
+def read_crate_text(crate_path: Path) -> str:
+    raw = crate_path.read_bytes()
+    for enc in ("utf-16-be", "utf-16-le", "utf-8", "latin1"):
+        text = raw.decode(enc, errors="ignore")
+        if "Users" in text or "Jukebox" in text:
+            return text
+    return raw.decode("latin1", errors="ignore")
+
+
+def parse_crate(crate_path: Path) -> list[TrackReference]:
+    text = read_crate_text(crate_path)
+
+    # Serato crate files often decode with weird spacing/null-ish characters.
+    # This finds paths from /Users/... through the audio extension without
+    # greedily scanning the entire file.
+    pattern = rf"/?Users/[^\r\n]+?\.(?:{AUDIO_EXTS})"
+
+    refs = []
+    for match in re.finditer(pattern, text):
+        raw_path = "/" + match.group(0).lstrip("/")
+        raw_path = raw_path.replace("\x00", "")
+        path = Path(raw_path)
+
+        refs.append(
+            TrackReference(
+                source=crate_path,
+                path=path,
+                filename=path.name,
+            )
+        )
+
+    return refs
+
+
+def parse_crates(root: Path) -> list[TrackReference]:
+    refs = []
+    for crate in root.rglob("*.crate"):
+        refs.extend(parse_crate(crate))
+    return refs