import os
import csv
from pathlib import Path
from typing import Tuple, Union

import torchaudio
from torch import Tensor
from torch.utils.data import Dataset
from torchaudio.datasets.utils import (
    download_url,
    extract_archive,
)

URL = "aew"
FOLDER_IN_ARCHIVE = "ARCTIC"
_CHECKSUMS = {
    "http://festvox.org/cmu_arctic/packed/cmu_us_aew_arctic.tar.bz2":
    "4382b116efcc8339c37e01253cb56295",
    "http://festvox.org/cmu_arctic/packed/cmu_us_ahw_arctic.tar.bz2":
    "b072d6e961e3f36a2473042d097d6da9",
    "http://festvox.org/cmu_arctic/packed/cmu_us_aup_arctic.tar.bz2":
    "5301c7aee8919d2abd632e2667adfa7f",
    "http://festvox.org/cmu_arctic/packed/cmu_us_awb_arctic.tar.bz2":
    "280fdff1e9857119d9a2c57b50e12db7",
    "http://festvox.org/cmu_arctic/packed/cmu_us_axb_arctic.tar.bz2":
    "5e21cb26c6529c533df1d02ccde5a186",
    "http://festvox.org/cmu_arctic/packed/cmu_us_bdl_arctic.tar.bz2":
    "b2c3e558f656af2e0a65da0ac0c3377a",
    "http://festvox.org/cmu_arctic/packed/cmu_us_clb_arctic.tar.bz2":
    "3957c503748e3ce17a3b73c1b9861fb0",
    "http://festvox.org/cmu_arctic/packed/cmu_us_eey_arctic.tar.bz2":
    "59708e932d27664f9eda3e8e6859969b",
    "http://festvox.org/cmu_arctic/packed/cmu_us_fem_arctic.tar.bz2":
    "dba4f992ff023347c07c304bf72f4c73",
    "http://festvox.org/cmu_arctic/packed/cmu_us_gka_arctic.tar.bz2":
    "24a876ea7335c1b0ff21460e1241340f",
    "http://festvox.org/cmu_arctic/packed/cmu_us_jmk_arctic.tar.bz2":
    "afb69d95f02350537e8a28df5ab6004b",
    "http://festvox.org/cmu_arctic/packed/cmu_us_ksp_arctic.tar.bz2":
    "4ce5b3b91a0a54b6b685b1b05aa0b3be",
    "http://festvox.org/cmu_arctic/packed/cmu_us_ljm_arctic.tar.bz2":
    "6f45a3b2c86a4ed0465b353be291f77d",
    "http://festvox.org/cmu_arctic/packed/cmu_us_lnh_arctic.tar.bz2":
    "c6a15abad5c14d27f4ee856502f0232f",
    "http://festvox.org/cmu_arctic/packed/cmu_us_rms_arctic.tar.bz2":
    "71072c983df1e590d9e9519e2a621f6e",
    "http://festvox.org/cmu_arctic/packed/cmu_us_rxr_arctic.tar.bz2":
    "3771ff03a2f5b5c3b53aa0a68b9ad0d5",
    "http://festvox.org/cmu_arctic/packed/cmu_us_slp_arctic.tar.bz2":
    "9cbf984a832ea01b5058ba9a96862850",
    "http://festvox.org/cmu_arctic/packed/cmu_us_slt_arctic.tar.bz2":
    "959eecb2cbbc4ac304c6b92269380c81",
}


def load_cmuarctic_item(line: str,
                        path: str,
                        folder_audio: str,
                        ext_audio: str) -> Tuple[Tensor, int, str, str]:

    utterance_id, transcript = line[0].strip().split(" ", 2)[1:]

    # Remove space, double quote, and single parenthesis from transcript
    transcript = transcript[1:-3]

    file_audio = os.path.join(path, folder_audio, utterance_id + ext_audio)

    # Load audio
    waveform, sample_rate = torchaudio.load(file_audio)

    return (
        waveform,
        sample_rate,
        transcript,
        utterance_id.split("_")[1]
    )


class CMUARCTIC(Dataset):
    """Create a Dataset for CMU_ARCTIC.

    Args:
        root (str or Path): Path to the directory where the dataset is found or downloaded.
        url (str, optional):
            The URL to download the dataset from or the type of the dataset to dowload.
            (default: ``"aew"``)
            Allowed type values are ``"aew"``, ``"ahw"``, ``"aup"``, ``"awb"``, ``"axb"``, ``"bdl"``,
            ``"clb"``, ``"eey"``, ``"fem"``, ``"gka"``, ``"jmk"``, ``"ksp"``, ``"ljm"``, ``"lnh"``,
            ``"rms"``, ``"rxr"``, ``"slp"`` or ``"slt"``.
        folder_in_archive (str, optional):
            The top-level directory of the dataset. (default: ``"ARCTIC"``)
        download (bool, optional):
            Whether to download the dataset if it is not found at root path. (default: ``False``).
    """

    _file_text = "txt.done.data"
    _folder_text = "etc"
    _ext_audio = ".wav"
    _folder_audio = "wav"

    def __init__(self,
                 root: Union[str, Path],
                 url: str = URL,
                 folder_in_archive: str = FOLDER_IN_ARCHIVE,
                 download: bool = False) -> None:

        if url in [
            "aew",
            "ahw",
            "aup",
            "awb",
            "axb",
            "bdl",
            "clb",
            "eey",
            "fem",
            "gka",
            "jmk",
            "ksp",
            "ljm",
            "lnh",
            "rms",
            "rxr",
            "slp",
            "slt"
        ]:

            url = "cmu_us_" + url + "_arctic"
            ext_archive = ".tar.bz2"
            base_url = "http://www.festvox.org/cmu_arctic/packed/"

            url = os.path.join(base_url, url + ext_archive)

        # Get string representation of 'root' in case Path object is passed
        root = os.fspath(root)

        basename = os.path.basename(url)
        root = os.path.join(root, folder_in_archive)
        if not os.path.isdir(root):
            os.mkdir(root)
        archive = os.path.join(root, basename)

        basename = basename.split(".")[0]

        self._path = os.path.join(root, basename)

        if download:
            if not os.path.isdir(self._path):
                if not os.path.isfile(archive):
                    checksum = _CHECKSUMS.get(url, None)
                    download_url(url, root, hash_value=checksum, hash_type="md5")
                extract_archive(archive)

        self._text = os.path.join(self._path, self._folder_text, self._file_text)

        with open(self._text, "r") as text:
            walker = csv.reader(text, delimiter="\n")
            self._walker = list(walker)

    def __getitem__(self, n: int) -> Tuple[Tensor, int, str, str]:
        """Load the n-th sample from the dataset.

        Args:
            n (int): The index of the sample to be loaded

        Returns:
            (Tensor, int, str, str): ``(waveform, sample_rate, transcript, utterance_id)``
        """
        line = self._walker[n]
        return load_cmuarctic_item(line, self._path, self._folder_audio, self._ext_audio)

    def __len__(self) -> int:
        return len(self._walker)
