traxsource: helper _split_title_mix + _format_artists + _large_cover + eccezioni

core/traxsource.py

@@ -6,6 +6,7 @@ Spec: docs/superpowers/specs/2026-08-01-traxsource-charts-design.md.
 
 from __future__ import annotations
 
+import re
 from dataclasses import dataclass
 
 
@@ -59,3 +60,47 @@ def list_genres() -> list:
     ]
     result.sort(key=lambda g: g["name"].casefold())
     return result
+
+
+class TraxsourceError(Exception):
+    """Base per errori Traxsource."""
+
+
+class TraxsourceUnreachableError(TraxsourceError):
+    """Rete / 5xx dopo retry."""
+
+
+class TraxsourceParseError(TraxsourceError):
+    """HTML ricevuto ma non conforme allo schema atteso."""
+
+
+_MIX_PAREN_RE = re.compile(r"^(.*)\s*\(([^()]+)\)\s*$")
+_SIZE_RE = re.compile(r"/\d+x\d+/")
+
+
+def _split_title_mix(full_title: str) -> tuple:
+    """Estrae mix dalle parentesi finali. 'Foo (Extended Mix)' -> ('Foo', 'Extended Mix').
+    Se non ci sono parentesi finali, mix = ''."""
+    if not full_title:
+        return ("", "")
+    m = _MIX_PAREN_RE.match(full_title.strip())
+    if m:
+        return (m.group(1).strip(), m.group(2).strip())
+    return (full_title.strip(), "")
+
+
+def _format_artists(names: list) -> str:
+    """['A', 'B', 'C'] -> 'A, B & C'. Strips whitespace."""
+    clean = [n.strip() for n in names if n and n.strip()]
+    if not clean:
+        return ""
+    if len(clean) == 1:
+        return clean[0]
+    return ", ".join(clean[:-1]) + " & " + clean[-1]
+
+
+def _large_cover(url: str) -> str:
+    """Sostituisce /NxN/ nel path con /500x500/. Se pattern assente, ritorna invariato."""
+    if not url:
+        return ""
+    return _SIZE_RE.sub("/500x500/", url)