import argparse
import importlib
import os
from argparse import RawTextHelpFormatter

import numpy as np
import torch
from torch.utils.data import DataLoader
from tqdm import tqdm

from TTS.tts.datasets.TTSDataset import TTSDataset
from TTS.tts.models import setup_model
from TTS.tts.utils.io import load_checkpoint
from TTS.tts.utils.text.symbols import make_symbols, phonemes, symbols
from TTS.utils.audio import AudioProcessor
from TTS.utils.io import load_config

if __name__ == "__main__":
    # pylint: disable=bad-option-value
    parser = argparse.ArgumentParser(
        description="""Extract attention masks from trained Tacotron/Tacotron2 models.
These masks can be used for different purposes including training a TTS model with a Duration Predictor.\n\n"""
        """Each attention mask is written to the same path as the input wav file with ".npy" file extension.
(e.g. path/bla.wav (wav file) --> path/bla.npy (attention mask))\n"""
        """
Example run:
    CUDA_VISIBLE_DEVICE="0" python TTS/bin/compute_attention_masks.py
        --model_path /data/rw/home/Models/ljspeech-dcattn-December-14-2020_11+10AM-9d0e8c7/checkpoint_200000.pth.tar
        --config_path /data/rw/home/Models/ljspeech-dcattn-December-14-2020_11+10AM-9d0e8c7/config.json
        --dataset_metafile /root/LJSpeech-1.1/metadata.csv
        --data_path /root/LJSpeech-1.1/
        --batch_size 32
        --dataset ljspeech
        --use_cuda True
""",
        formatter_class=RawTextHelpFormatter,
    )
    parser.add_argument("--model_path", type=str, required=True, help="Path to Tacotron/Tacotron2 model file ")
    parser.add_argument(
        "--config_path",
        type=str,
        required=True,
        help="Path to Tacotron/Tacotron2 config file.",
    )
    parser.add_argument(
        "--dataset",
        type=str,
        default="",
        required=True,
        help="Target dataset processor name from TTS.tts.dataset.preprocess.",
    )

    parser.add_argument(
        "--dataset_metafile",
        type=str,
        default="",
        required=True,
        help="Dataset metafile inclusing file paths with transcripts.",
    )
    parser.add_argument("--data_path", type=str, default="", help="Defines the data path. It overwrites config.json.")
    parser.add_argument("--use_cuda", type=bool, default=False, help="enable/disable cuda.")

    parser.add_argument(
        "--batch_size", default=16, type=int, help="Batch size for the model. Use batch_size=1 if you have no CUDA."
    )
    args = parser.parse_args()

    C = load_config(args.config_path)
    ap = AudioProcessor(**C.audio)

    # if the vocabulary was passed, replace the default
    if "characters" in C.keys():
        symbols, phonemes = make_symbols(**C.characters)

    # load the model
    num_chars = len(phonemes) if C.use_phonemes else len(symbols)
    # TODO: handle multi-speaker
    model = setup_model(C)
    model, _ = load_checkpoint(model, args.model_path, None, args.use_cuda)
    model.eval()

    # data loader
    preprocessor = importlib.import_module("TTS.tts.datasets.formatters")
    preprocessor = getattr(preprocessor, args.dataset)
    meta_data = preprocessor(args.data_path, args.dataset_metafile)
    dataset = TTSDataset(
        model.decoder.r,
        C.text_cleaner,
        compute_linear_spec=False,
        ap=ap,
        meta_data=meta_data,
        characters=C.characters if "characters" in C.keys() else None,
        add_blank=C["add_blank"] if "add_blank" in C.keys() else False,
        use_phonemes=C.use_phonemes,
        phoneme_cache_path=C.phoneme_cache_path,
        phoneme_language=C.phoneme_language,
        enable_eos_bos=C.enable_eos_bos_chars,
    )

    dataset.sort_and_filter_items(C.get("sort_by_audio_len", default=False))
    loader = DataLoader(
        dataset,
        batch_size=args.batch_size,
        num_workers=4,
        collate_fn=dataset.collate_fn,
        shuffle=False,
        drop_last=False,
    )

    # compute attentions
    file_paths = []
    with torch.no_grad():
        for data in tqdm(loader):
            # setup input data
            text_input = data[0]
            text_lengths = data[1]
            linear_input = data[3]
            mel_input = data[4]
            mel_lengths = data[5]
            stop_targets = data[6]
            item_idxs = data[7]

            # dispatch data to GPU
            if args.use_cuda:
                text_input = text_input.cuda()
                text_lengths = text_lengths.cuda()
                mel_input = mel_input.cuda()
                mel_lengths = mel_lengths.cuda()

            mel_outputs, postnet_outputs, alignments, stop_tokens = model.forward(text_input, text_lengths, mel_input)

            alignments = alignments.detach()
            for idx, alignment in enumerate(alignments):
                item_idx = item_idxs[idx]
                # interpolate if r > 1
                alignment = (
                    torch.nn.functional.interpolate(
                        alignment.transpose(0, 1).unsqueeze(0),
                        size=None,
                        scale_factor=model.decoder.r,
                        mode="nearest",
                        align_corners=None,
                        recompute_scale_factor=None,
                    )
                    .squeeze(0)
                    .transpose(0, 1)
                )
                # remove paddings
                alignment = alignment[: mel_lengths[idx], : text_lengths[idx]].cpu().numpy()
                # set file paths
                wav_file_name = os.path.basename(item_idx)
                align_file_name = os.path.splitext(wav_file_name)[0] + ".npy"
                file_path = item_idx.replace(wav_file_name, align_file_name)
                # save output
                file_paths.append([item_idx, file_path])
                np.save(file_path, alignment)

        # ourput metafile
        metafile = os.path.join(args.data_path, "metadata_attn_mask.txt")

        with open(metafile, "w", encoding="utf-8") as f:
            for p in file_paths:
                f.write(f"{p[0]}|{p[1]}\n")
        print(f" >> Metafile created: {metafile}")