import unittest.mock
import generator.comping
import generator.vocabulary
import generator.parts
import generator.arrange.form
import generator.arrange.generate

def section_document(document, part_type):
  prepared = generator.parts.prepare_document(document)
  role = {'acoustic': 'accompaniment', 'electric': 'melody', 'vocal': 'vocal'}[part_type]
  section = generator.arrange.form.ArrangementSection('', 0, len(prepared['staves'][0]['measures']), 0, role)
  with unittest.mock.patch('generator.arrange.form.full_arrangement_sections', return_value=[section]), generator.vocabulary.using(generator.vocabulary.load(), part_type + '_accompaniment'):
    backing = generator.comping.Canonical(prepared, part_type, 'fixture') if part_type == 'acoustic' else None
    return generator.arrange.generate._arrange_document(prepared, part_type, accompaniment=backing)

def melody_performance(document, part_type):
  """Isolate unchanged source melody from accompaniment/ending construction."""
  return generator.arrange.generate._arrange_document(generator.parts.prepare_document(document), part_type, owned={'melody', 'vocal'})