import argparse
import copy
from fractions import Fraction
from pathlib import Path
import tempfile
import unittest
from unittest.mock import patch

from generator import harmony
from generator.__main__ import generate_assets
from generator.arrange.generate import active_chord, arrange_document, generated_voice, propagated_chords
from generator.arrange.fretboard import pitches_for_voicing
from generator.model import beat_lengths, fraction, key_from_fifths, pitch_number, rational, validate_document
from generator.musicxml import load_musicxml
from generator.styles import BUILT_IN_STYLES, canonical_style
from generator.transposition import concert_document, shift_pitch, transpose_document
from tests.test_musicxml import parse, notes, xml_note, xml_score

class MusicModelTests(unittest.TestCase):
  def setUp(self):
    engraving = patch('generator.__main__.engrave_tree')
    engraving.start()
    self.addCleanup(engraving.stop)
    catalogue = patch('generator.__main__.build_catalogue')
    catalogue.start()
    self.addCleanup(catalogue.stop)
  def test_chord_semantics_are_not_voicing_heuristics(self):
    cases = {'C': {0, 4, 7}, 'Cdim': {0, 3, 6}, 'Cdim7': {0, 3, 6, 9}, 'Csus2': {0, 2, 7},
      'C7b5': {0, 4, 6, 10}, 'G7b9': {7, 11, 2, 5, 8}, 'Fmaj7#11': {5, 9, 0, 4, 11}}
    for label, expected in cases.items():
      self.assertEqual(set(harmony.pitch_classes(harmony.parse_symbol(label))), expected, label)
    for label, essentials in [('G7b9', {11, 5, 8}), ('C13', {4, 10, 9})]:
      pitches = pitches_for_voicing(label)
      self.assertTrue(essentials.issubset({pitch_number(p) % 12 for p in pitches}), label)
    with self.assertRaises(ValueError):
      harmony.parse_symbol('Cunrecognised')
  def test_transposition_preserves_spelling_octaves_modes(self):
    for p in ({'letter': 'b', 'alter': 1, 'octave': 4}, {'letter': 'c', 'alter': -1, 'octave': 4}, {'letter': 'f', 'alter': 2, 'octave': 4}):
      p['alter'] = rational(p['alter'])
      self.assertEqual(shift_pitch(p, 0, 0), p)
      self.assertEqual(pitch_number(shift_pitch(p, 1, 2)), pitch_number(p) + 2)
    source = parse(xml_score(xml_note(), attributes='<key><fifths>-3</fifths><mode>minor</mode></key>'))
    result = transpose_document(source, 'D')
    self.assertEqual(result['metadata']['key_signature'], 'D minor')
    self.assertEqual(result['metadata']['key']['alterations'], key_from_fifths(-1, 'minor')['alterations'])
  def test_additive_and_compound_grouping(self):
    self.assertEqual(beat_lengths({'groups': [{'beats': [3, 2], 'unit': 8}]}), [Fraction(3, 2), Fraction(1)])
    self.assertEqual(beat_lengths({'groups': [{'beats': [6], 'unit': 8}]}), [Fraction(3, 2)] * 2)
    self.assertEqual(beat_lengths({'groups': [{'beats': [3], 'unit': 4}]}), [Fraction(1)] * 3)
  def test_generated_rhythm_follows_mid_measure_meter(self):
    change = '<attributes><time><beats>6</beats><beat-type>8</beat-type></time></attributes>'
    source = parse(xml_score(xml_note(duration=1, kind='quarter') + change + xml_note(duration=3, kind='half', extra='<dot/>')))
    measure = source['staves'][0]['measures'][0]
    events = generated_voice(measure, 'slash', None)
    self.assertEqual([fraction(n['onset']) for n in events], [0, 1, Fraction(5, 2)])
    self.assertEqual([fraction(n['duration']) for n in events], [1, Fraction(3, 2), Fraction(3, 2)])
  def test_harmony_carry_uses_last_event_and_never_future_event(self):
    c = harmony.parse_symbol('C7') | {'onset': rational(0)}
    f = harmony.parse_symbol('F7') | {'onset': rational(2)}
    measures = [{'harmonies': [c, f]}, {'harmonies': []}]
    self.assertEqual(propagated_chords(measures), [None, f])
    self.assertIsNone(active_chord({'harmonies': [f]}, Fraction(0), None))
    self.assertEqual(active_chord(measures[0], Fraction(1), None), c)
  def test_tuplet_ratios_and_tie_links_validated(self):
    document = parse(xml_score(xml_note()))
    notes(document)[0]['pitches'][0]['tie_to'] = 'missing'
    with self.assertRaisesRegex(ValueError, 'dangling tie'):
      validate_document(document)
    document = parse(xml_score(xml_note()))
    notes(document)[0]['duration'] = {'numerator': 8, 'denominator': 2}
    with self.assertRaisesRegex(ValueError, 'reduced'):
      validate_document(document)
  def test_optional_turnaround_and_form(self):
    source = load_musicxml(Path('data/songs/it-could-happen-to-you.xml'))
    for part in ('acoustic', 'electric', 'vocal'):
      result = arrange_document(source, part)
      validate_document(result)
      measures = result['staves'][0]['measures']
      self.assertEqual(sum(bool(m.get('section_label')) for m in measures), 7)
      self.assertFalse(measures[-1]['harmonies'])
      self.assertTrue(any(h for m in measures[:-1] for h in m['harmonies']))
      self.assertFalse(any('chord_optional' in h for m in measures for h in m['harmonies']))
  def test_player_styles_preserved(self):
    self.assertEqual(len(BUILT_IN_STYLES), 50)
    for text in ('Med.', 'Med. Swing', 'Medium', 'Medium Swing'):
      self.assertEqual(canonical_style(text), 'Medium Swing')
    with self.assertRaises(ValueError):
      canonical_style('Unrecognised style')
  def test_failure_preserves_generated_assets(self):
    with tempfile.TemporaryDirectory() as temp:
      root = Path(temp)
      data = root / 'data'
      (data / 'songs').mkdir(parents=True)
      (data / 'songs' / 'bad.xml').write_text(xml_score(xml_note(duration=5)), encoding='utf-8')
      output = root / 'output'
      output.mkdir()
      (output / 'last-good').write_text('preserved')
      args = argparse.Namespace(data_dir=data, output_dir=output, static_assets_dir=Path('package/assets'), check=False)
      with self.assertRaises(ValueError):
        generate_assets(args)
      self.assertEqual((output / 'last-good').read_text(), 'preserved')
      (data / 'songs' / 'bad.xml').write_text(xml_score(xml_note()), encoding='utf-8')
      args.check = True
      with self.assertRaisesRegex(ValueError, 'summary'):
        generate_assets(args)
      self.assertEqual((output / 'last-good').read_text(), 'preserved')
  def test_instrument_transposition_is_converted_once(self):
    source = parse(xml_score(xml_note(), attributes='<transpose><diatonic>-1</diatonic><chromatic>-2</chromatic></transpose>'))
    concert = concert_document(source)
    p = notes(concert)[0]['pitches'][0]
    self.assertEqual((p['letter'], fraction(p['alter']), p['octave']), ('b', -1, 3))
    self.assertEqual(concert_document(concert), concert)
    self.assertEqual(concert['metadata']['key_signature'], 'Bb')
  def test_deterministic_generation_and_removal(self):
    with tempfile.TemporaryDirectory() as temp:
      data, output = Path(temp) / 'data', Path(temp) / 'output'
      (data / 'songs').mkdir(parents=True)
      source = data / 'songs' / 'fixture.xml'
      source.write_text(xml_score(xml_note()), encoding='utf-8')
      args = argparse.Namespace(data_dir=data, output_dir=output, static_assets_dir=Path('package/assets'), check=False)
      generate_assets(args)
      first = {p.relative_to(output): p.read_bytes() for p in output.rglob('*') if p.is_file()}
      generate_assets(args)
      self.assertEqual(first, {p.relative_to(output): p.read_bytes() for p in output.rglob('*') if p.is_file()})
      source.unlink()
      generate_assets(args)
      self.assertFalse(list(output.rglob('*.json')))
      self.assertFalse(list(output.rglob('*.png')))
  def test_pickup_tie_survives_vocal_restoration(self):
    source = xml_score(xml_note(duration=1, kind='quarter', extra='<tie type="start"/>'), implicit=True)
    source = source.replace('</measure></part>', '</measure><measure number="2">' + xml_note(extra='<tie type="stop"/>') + '</measure></part>')
    result = arrange_document(parse(source), 'vocal')
    validate_document(result)
    measures = result['staves'][0]['measures']
    start = measures[0]['voices'][0]['notes'][-1]['pitches'][0]
    end = measures[1]['voices'][0]['notes'][0]['pitches'][0]
    self.assertEqual(start['tie_to'], end['id'])