from __future__ import annotations

import pathlib

import generator.accompaniment
import generator.guitar
import generator.musicxml
import generator.parts
import generator.rhythm
import generator.scat
import generator.score

def practice_document(document: dict, part_type: str, *, rhythms: generator.rhythm.Library) -> dict:
  document = generator.parts.prepare_document(document, practice=True)
  plan = generator.accompaniment.plan_section(generator.score.source_staff(document)['measures'], rhythms, electric=False) if part_type == 'acoustic' else None
  return _practice_document(document, part_type, plan)

def _practice_document(document: dict, part_type: str, plan: generator.accompaniment.Plan | None) -> dict:
  if part_type not in generator.parts.PART_TYPES:
    raise ValueError(f'unknown practice part: {part_type}')
  staff = generator.score.source_staff(document)
  previous = generator.accompaniment.carried_chords(staff['measures'])
  role = {'acoustic': 'accompaniment', 'electric': 'melody', 'vocal': 'vocal'}[part_type]
  if part_type == 'acoustic' and plan is None:
    raise ValueError('acoustic practice requires a rhythm plan')
  measures = [generator.parts.build_measure(m, f'measure-{i + 1}', role, part_type, previous[i], m.get('section_label', ''), plan.acoustic[i] if part_type == 'acoustic' else None) for i, m in enumerate(staff['measures'])]
  for measure in measures:
    for chord in measure['harmonies']:
      chord.pop('chord_optional', None)
  tuplets = generator.score.reidentify(measures, staff.get('tuplets', []))
  result = generator.score.make_arranged_document(document, staff, staff_id='staff-practice-' + part_type, staff_name=part_type.capitalize(), role='vocal' if part_type == 'vocal' else 'guitar', arrangement_part_type=part_type, measures=measures, tuplets=tuplets, octave_shifts=staff.get('octave_shifts', []) if role in ('melody', 'vocal') else [])
  if part_type == 'vocal':
    generator.scat.add_scat(result)
  else:
    generator.guitar.place_guitar(result)
    if generator.accompaniment.connect_continuations(result):
      generator.guitar.place_guitar(result)
  return result

def generate_practice_scores(source_dir: pathlib.Path, output_dir: pathlib.Path, *, rhythms: generator.rhythm.Library) -> int:
  sources = generator.parts.source_paths(source_dir, practice=True)
  for path in sources:
    try:
      document = generator.parts.prepare_document(generator.musicxml.load_musicxml(path), practice=True)
      plan = generator.accompaniment.plan_section(generator.score.source_staff(document)['measures'], rhythms, electric=False)
    except ValueError as error:
      raise ValueError(f'{path}: {error}') from error
    for part in generator.parts.PART_TYPES:
      try:
        generator.score.write_json(output_dir / path.stem / (part + '.json'), _practice_document(document, part, plan))
      except ValueError as error:
        raise ValueError(f'{path}, part {part}: {error}') from error
  return len(sources) * len(generator.parts.PART_TYPES)