Cleanup

generator/arrange/fretboard.py

@@ -15,6 +15,12 @@ class TabPosition(NamedTuple):
   midi: int
 
 
+class ChordSymbol(NamedTuple):
+  root: str
+  quality: str
+  bass: str
+
+
 ROOTS = {
   "C": 0,
   "C#": 1,
@@ -37,6 +43,7 @@ ROOTS = {
 
 
 def parse_root(symbol: str) -> tuple[str, str] | None:
+  symbol = symbol.strip()
   if not symbol or symbol[0].upper() not in "ABCDEFG":
     return None
   length = 1
@@ -45,36 +52,97 @@ def parse_root(symbol: str) -> tuple[str, str] | None:
   return symbol[:length], symbol[length:]
 
 
+def parse_chord_symbol(symbol: str) -> ChordSymbol | None:
+  clean = symbol.strip().replace(" ", "")
+  base, _, slash = clean.partition("/")
+  parsed = parse_root(base)
+  if parsed is None:
+    return None
+  root, quality = parsed
+  bass = ""
+  if slash:
+    bass_parsed = parse_root(slash)
+    if bass_parsed is not None:
+      bass = bass_parsed[0]
+  return ChordSymbol(root, quality, bass)
+
+
+def unique_intervals(values: tuple[int, ...]) -> tuple[int, ...]:
+  result: list[int] = []
+  seen: set[int] = set()
+  for value in values:
+    interval = mod12(value)
+    if interval in seen:
+      continue
+    seen.add(interval)
+    result.append(interval)
+  return tuple(result)
+
+
+def color_intervals(value: str) -> tuple[int, ...]:
+  colors: list[int] = []
+  if "alt" in value:
+    colors.append(1)
+  if "b9" in value:
+    colors.append(1)
+  if "#9" in value:
+    colors.append(3)
+  if "9" in value and "b9" not in value and "#9" not in value:
+    colors.append(2)
+  if "#11" in value:
+    colors.append(6)
+  elif "11" in value:
+    colors.append(5)
+  if "b13" in value:
+    colors.append(8)
+  elif "13" in value:
+    colors.append(9)
+  return tuple(colors)
+
+
 def chord_intervals(quality: str) -> tuple[int, ...]:
-  value = quality.lower()
+  value = quality.lower().replace(" ", "")
   if "7b5" in value or "ø" in value or "half" in value:
     return (0, 3, 6, 10)
   if "dim" in value or "o" in value:
     return (0, 3, 6, 9)
+  colors = color_intervals(value)
   if "aug" in value or "+" in value:
-    return (0, 4, 8, 10)
+    return unique_intervals((0, 4, 8, 10) + colors) if ("7" in value or colors) else (0, 4, 8)
   if "sus" in value:
-    return (0, 5, 7, 10)
-  if value.startswith("-") or (value.startswith("m") and not value.startswith("maj")):
-    return (0, 3, 7, 10 if "7" in value else 10)
-  if "maj7" in value or "ma7" in value or "Δ" in value:
-    return (0, 4, 7, 11)
+    return unique_intervals((0, 5, 10) + colors) if ("7" in value or colors) else (0, 5, 7)
+  minor = value.startswith("-") or (value.startswith("m") and not value.startswith(("maj", "ma")))
+  if minor:
+    if "6" in value and "7" not in value:
+      return unique_intervals((0, 3, 7, 9) + colors)
+    if "7" in value or colors:
+      return unique_intervals((0, 3, 10) + colors)
+    return (0, 3, 7)
+  if "maj" in value or value.startswith("ma") or "Δ" in value:
+    return unique_intervals((0, 4, 11) + colors)
   if "6" in value and "7" not in value:
-    return (0, 4, 7, 9)
-  if "7" in value:
-    return (0, 4, 7, 10)
+    return unique_intervals((0, 4, 7, 9) + colors)
+  if "7" in value or colors:
+    return unique_intervals((0, 4, 10) + colors)
   return (0, 4, 7)
 
 
+def pitch_class_for_root(root: str) -> int | None:
+  return ROOTS.get(root[0].upper() + root[1:], ROOTS.get(root.upper()))
+
+
 def chord_pitch_classes(symbol: str) -> tuple[int, ...]:
-  parsed = parse_root(symbol)
+  parsed = parse_chord_symbol(symbol)
   if parsed is None:
     return ()
-  root, quality = parsed
-  root_pc = ROOTS.get(root[0].upper() + root[1:], ROOTS.get(root.upper()))
+  root_pc = pitch_class_for_root(parsed.root)
   if root_pc is None:
     return ()
-  return tuple(mod12(root_pc + interval) for interval in chord_intervals(quality))
+  pitch_classes = [mod12(root_pc + interval) for interval in chord_intervals(parsed.quality)]
+  bass_pc = pitch_class_for_root(parsed.bass) if parsed.bass else None
+  if bass_pc is not None and bass_pc not in pitch_classes:
+    pitch_classes.append(bass_pc)
+  return tuple(pitch_classes)
 
 
 def positions_for_string(string_number: int, open_midi: int, pitch_classes: tuple[int, ...]) -> list[TabPosition]:
@@ -148,4 +216,3 @@ def pitch_from_midi(midi: int) -> dict[str, int | str]:
 
 def pitches_for_voicing(symbol: str) -> list[dict[str, int | str]]:
   return [pitch_from_midi(position.midi + WRITTEN_GUITAR_OCTAVE_OFFSET) for position in find_playable_voicing(symbol)]
-