import argparse
import copy
from fractions import Fraction
from pathlib import Path
import tempfile
import unittest

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 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}):
            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.musicxml'))
        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.musicxml').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'),clean=True,check=False)
            with self.assertRaises(ValueError):
                generate_assets(args)
            self.assertEqual((output/'last-good').read_text(),'preserved')
            (data/'songs'/'bad.musicxml').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'],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.musicxml'
            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'),clean=True,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')))

    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'])