Cleanup

generator/arrange/form.py

@@ -1,8 +1,12 @@
 from __future__ import annotations
 
 import dataclasses
+import fractions
 import typing
 
+import generator.arrange.ending_plan
+import generator.arrange.pickup
+import generator.model
 import generator.score
 
 @dataclasses.dataclass(frozen=True)
@@ -55,3 +59,57 @@ def full_arrangement_sections(measures: list[dict], part_type: str) -> list[Arra
     for label, start, count, index in specs
     if count > 0
   ]
+
+@dataclasses.dataclass(frozen=True)
+class FormPlan:
+  sections: tuple[ArrangementSection, ...]
+  windows: tuple[tuple[fractions.Fraction, fractions.Fraction, str], ...]
+  stops: tuple[tuple[int, fractions.Fraction] | None, ...]
+  @classmethod
+  def read(cls, document, part):
+    source = generator.score.source_staff(document)['measures']
+    sections = tuple(full_arrangement_sections(source, part))
+    stops = tuple(section_stop(source, section, sections[i + 1] if i + 1 < len(sections) else None) for i, section in enumerate(sections))
+    return cls(sections, _windows(document, part, sections), stops)
+
+def section_stop(source, section, following):
+  if following is None or not generator.score.body_start_measure_index(source):
+    return None
+  last = section.source_measure_index + section.measure_count - 1
+  pad = generator.arrange.pickup.offset(source[last], source[0])
+  if following.role == 'slash':
+    return last, pad
+  if following.role == 'melody' and generator.arrange.pickup.enters(following, source):
+    attacks = [generator.model.fraction(note['onset']) for note in generator.score.measure_notes(source[0]) if note['pitches']]
+    if attacks:
+      return last, pad + min(attacks)
+  return None
+
+def windows(document, part):
+  return FormPlan.read(document, part).windows
+
+def _windows(document, part, sections):
+  source = generator.score.source_staff(document)['measures']
+  result, cursor = [], fractions.Fraction()
+  for section in sections:
+    duration = sum((generator.model.fraction(m['duration']) for m in source[section.source_measure_index:section.source_measure_index + section.measure_count]), fractions.Fraction())
+    role = {'slash': 'solo', 'vocal': 'melody'}.get(section.role, section.role)
+    if section.role in ('vocal', 'melody') and generator.arrange.pickup.enters(section, source) and result:
+      attacks = [generator.model.fraction(n['onset']) for n in generator.score.measure_notes(source[0]) if n['pitches']]
+      if attacks:
+        start = cursor - generator.model.fraction(source[0]['duration']) + min(attacks)
+        a, _, old = result[-1]
+        result[-1] = (a, start, old)
+        result.append((start, cursor, part + '_' + role))
+    end = cursor + duration
+    start = cursor
+    if section.role == 'slash' and generator.score.body_start_measure_index(source) and result:
+      # Allocate the source's complete pickup bar before composition. This
+      # does not inspect either generated solo; a role may leave it silent.
+      start = cursor - generator.model.fraction(source[0]['duration'])
+      a, _, old = result[-1]
+      result[-1] = (a, start, old)
+    result.append((start, end, part + '_' + role))
+    cursor = end
+  result.append((cursor, cursor + generator.arrange.ending_plan.duration(source), part + ('_accompaniment' if part != 'vocal' else '_rest')))
+  return tuple(result)