# Copyright (c) 2020, NVIDIA CORPORATION.  All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import os

import lightning.pytorch as pl
import torch
from lightning.pytorch import seed_everything
from omegaconf import OmegaConf

from nemo.collections.asr.models import EncDecSpeakerLabelModel
from nemo.core.config import hydra_runner
from nemo.utils import logging
from nemo.utils.exp_manager import exp_manager

seed_everything(42)


@hydra_runner(config_path="conf", config_name="titanet-finetune.yaml")
def main(cfg):

    logging.info(f'Hydra config: {OmegaConf.to_yaml(cfg)}')
    trainer = pl.Trainer(**cfg.trainer)
    log_dir = exp_manager(trainer, cfg.get("exp_manager", None))
    speaker_model = EncDecSpeakerLabelModel(cfg=cfg.model, trainer=trainer)
    speaker_model.maybe_init_from_pretrained_checkpoint(cfg)

    # save labels to file
    if log_dir is not None:
        with open(os.path.join(log_dir, 'labels.txt'), 'w') as f:
            if speaker_model.labels is not None:
                for label in speaker_model.labels:
                    f.write(f'{label}\n')

    trainer.fit(speaker_model)

    torch.distributed.destroy_process_group()
    if hasattr(cfg.model, 'test_ds') and cfg.model.test_ds.manifest_filepath is not None:
        if trainer.is_global_zero:
            trainer = pl.Trainer(devices=1, accelerator=cfg.trainer.accelerator, strategy=cfg.trainer.strategy)
            if speaker_model.prepare_test(trainer):
                trainer.test(speaker_model)


if __name__ == '__main__':
    main()