import dataclasses
import itertools
from pathlib import Path
from typing import List

import datasets

datasets.logging.set_verbosity_info()

_DESCRIPTION = """\
Dataset of music tablature, in alphaTex (https://alphatab.net/docs/alphatex) 
format, converted from Guitar Pro files (gp3, gp4, gp5, which are downloaded 
from https://rutracker.org/forum/viewtopic.php?t=2888130
"""

INSTRUMENT_MAP = {
    0: "Acoustic Grand Piano",
    1: "Bright Grand Piano",
    2: "Electric Grand Piano",
    3: "Honky tonk Piano",
    4: "Electric Piano 1",
    5: "Electric Piano 2",
    6: "Harpsichord",
    7: "Clavinet",
    8: "Celesta",
    9: "Glockenspiel",
    10: "Musicbox",
    11: "Vibraphone",
    12: "Marimba",
    13: "Xylophone",
    14: "Tubularbells",
    15: "Dulcimer",
    16: "Drawbar Organ",
    17: "Percussive Organ",
    18: "Rock Organ",
    19: "Church Organ",
    20: "Reed Organ",
    21: "Accordion",
    22: "Harmonica",
    23: "Tango Accordion",
    24: "Acoustic Guitar Nylon",
    25: "Acoustic Guitar Steel",
    26: "Electric Guitar Jazz",
    27: "Electric Guitar Clean",
    28: "Electric Guitar Muted",
    29: "Overdriven Guitar",
    30: "Distortion Guitar",
    31: "Guitar Harmonics",
    32: "Acoustic Bass",
    33: "Electric Bass Finger",
    34: "Electric Bass Pick",
    35: "Fretless Bass",
    36: "Slap Bass 1",
    37: "Slap Bass 2",
    38: "Synth Bass 1",
    39: "Synth Bass 2",
    40: "Violin",
    41: "Viola",
    42: "Cello",
    43: "Contrabass",
    44: "Tremolo Strings",
    45: "Pizzicato Strings",
    46: "Orchestral Harp",
    47: "Timpani",
    48: "String Ensemble 1",
    49: "String Ensemble 2",
    50: "Synth Strings 1",
    51: "Synth Strings 2",
    52: "Choir Aahs",
    53: "Voice Oohs",
    54: "Synth Voice",
    55: "Orchestra Hit",
    56: "Trumpet",
    57: "Trombone",
    58: "Tuba",
    59: "Muted Trumpet",
    60: "French Horn",
    61: "Brass Section",
    62: "Synth Brass 1",
    63: "Synth Brass 2",
    64: "Soprano Sax",
    65: "Alto Sax",
    66: "Tenor Sax",
    67: "Baritone Sax",
    68: "Oboe",
    69: "English Horn",
    70: "Bassoon",
    71: "Clarinet",
    72: "Piccolo",
    73: "Flute",
    74: "Recorder",
    75: "Pan Flute",
    76: "Blown bottle",
    77: "Shakuhachi",
    78: "Whistle",
    79: "Ocarina",
    80: "Lead 1 Square",
    81: "Lead 2 Sawtooth",
    82: "Lead 3 Calliope",
    83: "Lead 4 Chiff",
    84: "Lead 5 Charang",
    85: "Lead 6 Voice",
    86: "Lead 7 Fifths",
    87: "Lead 8 Bass and Lead",
    88: "Pad 1 newage",
    89: "Pad 2 warm",
    90: "Pad 3 polysynth",
    91: "Pad 4 choir",
    92: "Pad 5 bowed",
    93: "Pad 6 metallic",
    94: "Pad 7 halo",
    95: "Pad 8 sweep",
    96: "Fx 1 rain",
    97: "Fx 2 soundtrack",
    98: "Fx 3 crystal",
    99: "Fx 4 atmosphere",
    100: "Fx 5 brightness",
    101: "Fx 6 goblins",
    102: "Fx 7 echoes",
    103: "Fx 8 scifi",
    104: "Sitar",
    105: "Banjo",
    106: "Shamisen",
    107: "Koto",
    108: "Kalimba",
    109: "Bag pipe",
    110: "Fiddle",
    111: "Shanai",
    112: "Tinkle Bell",
    113: "Agogo",
    114: "Steel Drums",
    115: "Woodblock",
    116: "Taiko Drum",
    117: "Melodic Tom",
    118: "Synth Drum",
    119: "Reverse Cymbal",
    120: "Guitar Fret Noise",
    121: "Breath Noise",
    122: "Seashore",
    123: "Bird Tweet",
    124: "Telephone Ring",
    125: "Helicopter",
    126: "Applause",
    127: "Gunshot",
}


@dataclasses.dataclass
class Example:
    text: str
    track_name: str
    track_number: int
    instrument_name: str
    instrument_number: int
    title: str = None
    tempo: int = None
    tuning: str = None
    frets: int = None
    file: str = None
    subtitle: str = None
    artist: str = None
    album: str = None
    words: str = None
    music: str = None


class Builder(datasets.GeneratorBasedBuilder):
    VERSION = datasets.Version("1.4.1")

    def _info(self):
        return datasets.DatasetInfo(
            description=_DESCRIPTION,
            features=datasets.Features(
                {
                    field: datasets.Value("int32")
                    if type_ == int
                    else datasets.Value("string")
                    for field, type_ in Example.__annotations__.items()
                }
            ),
        )

    def _split_generators(self, dl_manager: datasets.DownloadManager):
        data_dir = dl_manager.download_and_extract("data.zip")
        if paths := list(Path(data_dir).glob("**/*.tex")):
            print(f"Found {len(paths)} AlphaTex files")
        else:
            raise ValueError(f"No GP files found in {data_dir}")

        return [
            datasets.SplitGenerator(
                name=datasets.Split.TRAIN,
                gen_kwargs={
                    "filepaths": paths,
                },
            ),
        ]

    def _generate_examples(self, filepaths):
        for idx, path in enumerate(filepaths):
            with open(path) as f:
                examples = _parse_examples(f.read())
            for example in examples:
                example.file = path.name
                yield f"{idx}-{example.track_number}", example.__dict__


def _parse_examples(tex: str) -> List[Example]:
    """
    Returns a dictionary for each track
    """
    examples = []
    data = {}

    def _parse_track_header_line(k, v):
        if k == "instrument":
            data['instrument_name'] = INSTRUMENT_MAP.get(int(v), "unknown")
            data['instrument_number'] = int(v)
        elif k == "tuning":
            data['tuning'] = v.split(" ")
        elif k == "frets":
            data['frets'] = int(v)

    lines = (l_.strip() for l_ in tex.splitlines() if l_.strip())
    song_header_lines = list(itertools.takewhile(lambda l: l != ".", lines))

    for line in song_header_lines:
        assert line.startswith("\\")
        line = line.lstrip("\\")
        kv = line.split(" ", 1)
        if len(kv) == 1:
            continue
        k, v = kv
        if k in [
            "title",
            "subtitle",
            "artist",
            "album",
            "words",
            "music",
        ]:
            data[k] = v.strip('"').strip("'")
        elif k == "tempo":
            data['tempo'] = int(v)
        else:
            _parse_track_header_line(k, v)

    track_header_lines = []
    track_tex_lines = []

    def _new_example():
        nonlocal data, track_header_lines, track_tex_lines
        data['track_number'] = (track_number := len(examples) + 1)
        data['track_name'] = v if v else f"Track {track_number}"
        data['text'] = (
            '\n'.join(
                song_header_lines +
                ["."] +
                track_header_lines +
                [" ".join(track_tex_lines)]
            )
        )
        examples.append(Example(**data))
        data = {}
        track_header_lines = []
        track_tex_lines = []

    for line in lines:
        if line.startswith("\\"):
            if len(kv := line.lstrip("\\").split(" ", 1)) == 2:
                k = kv[0]
                v = kv[1].strip('"').strip("'")
            else:
                k = kv[0]
                v = None
            if k == "track":
                if track_tex_lines:
                    _new_example()
            else:
                _parse_track_header_line(k, v)
            track_header_lines.append(line)
        else:
            track_tex_lines.append(line)
    if track_tex_lines:
        _new_example()
    return [t for t in examples if t.text]