#!/usr/bin/env python
# Copyright 2021 The HuggingFace Inc. team. 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.

# /// script
# dependencies = [
#     "transformers @ git+https://github.com/huggingface/transformers.git",
#     "datasets[audio]>=1.14.0",
#     "evaluate",
#     "librosa",
#     "torchaudio",
#     "torch>=1.6",
# ]
# ///

import logging
import os
import sys
from dataclasses import dataclass, field
from random import randint

import datasets
import evaluate
import numpy as np
from datasets import DatasetDict, load_dataset

import transformers
from transformers import (
    AutoConfig,
    AutoFeatureExtractor,
    AutoModelForAudioClassification,
    HfArgumentParser,
    Trainer,
    TrainingArguments,
    set_seed,
)
from transformers.utils import check_min_version
from transformers.utils.versions import require_version


logger = logging.getLogger(__name__)

# Will error if the minimal version of Transformers is not installed. Remove at your own risks.
check_min_version("4.57.0.dev0")

require_version("datasets>=1.14.0", "To fix: pip install -r examples/pytorch/audio-classification/requirements.txt")


def random_subsample(wav: np.ndarray, max_length: float, sample_rate: int = 16000):
    """Randomly sample chunks of `max_length` seconds from the input audio"""
    sample_length = int(round(sample_rate * max_length))
    if len(wav) <= sample_length:
        return wav
    random_offset = randint(0, len(wav) - sample_length - 1)
    return wav[random_offset : random_offset + sample_length]


@dataclass
class DataTrainingArguments:
    """
    Arguments pertaining to what data we are going to input our model for training and eval.
    Using `HfArgumentParser` we can turn this class
    into argparse arguments to be able to specify them on
    the command line.
    """

    dataset_name: str | None = field(default=None, metadata={"help": "Name of a dataset from the datasets package"})
    dataset_config_name: str | None = field(
        default=None, metadata={"help": "The configuration name of the dataset to use (via the datasets library)."}
    )
    train_file: str | None = field(
        default=None, metadata={"help": "A file containing the training audio paths and labels."}
    )
    eval_file: str | None = field(
        default=None, metadata={"help": "A file containing the validation audio paths and labels."}
    )
    train_split_name: str = field(
        default="train",
        metadata={
            "help": "The name of the training data set split to use (via the datasets library). Defaults to 'train'"
        },
    )
    eval_split_name: str = field(
        default="validation",
        metadata={
            "help": (
                "The name of the training data set split to use (via the datasets library). Defaults to 'validation'"
            )
        },
    )
    audio_column_name: str = field(
        default="audio",
        metadata={"help": "The name of the dataset column containing the audio data. Defaults to 'audio'"},
    )
    label_column_name: str = field(
        default="label", metadata={"help": "The name of the dataset column containing the labels. Defaults to 'label'"}
    )
    max_train_samples: int | None = field(
        default=None,
        metadata={
            "help": (
                "For debugging purposes or quicker training, truncate the number of training examples to this "
                "value if set."
            )
        },
    )
    max_eval_samples: int | None = field(
        default=None,
        metadata={
            "help": (
                "For debugging purposes or quicker training, truncate the number of evaluation examples to this "
                "value if set."
            )
        },
    )
    max_length_seconds: float = field(
        default=20,
        metadata={"help": "Audio clips will be randomly cut to this length during training if the value is set."},
    )


@dataclass
class ModelArguments:
    """
    Arguments pertaining to which model/config/tokenizer we are going to fine-tune from.
    """

    model_name_or_path: str = field(
        default="facebook/wav2vec2-base",
        metadata={"help": "Path to pretrained model or model identifier from huggingface.co/models"},
    )
    config_name: str | None = field(
        default=None, metadata={"help": "Pretrained config name or path if not the same as model_name"}
    )
    cache_dir: str | None = field(
        default=None, metadata={"help": "Where do you want to store the pretrained models downloaded from the Hub"}
    )
    model_revision: str = field(
        default="main",
        metadata={"help": "The specific model version to use (can be a branch name, tag name or commit id)."},
    )
    feature_extractor_name: str | None = field(default=None, metadata={"help": "Name or path of preprocessor config."})
    freeze_feature_encoder: bool = field(
        default=True, metadata={"help": "Whether to freeze the feature encoder layers of the model."}
    )
    attention_mask: bool = field(
        default=True, metadata={"help": "Whether to generate an attention mask in the feature extractor."}
    )
    token: str = field(
        default=None,
        metadata={
            "help": (
                "The token to use as HTTP bearer authorization for remote files. If not specified, will use the token "
                "generated when running `hf auth login` (stored in `~/.huggingface`)."
            )
        },
    )
    trust_remote_code: bool = field(
        default=False,
        metadata={
            "help": (
                "Whether to trust the execution of code from datasets/models defined on the Hub."
                " This option should only be set to `True` for repositories you trust and in which you have read the"
                " code, as it will execute code present on the Hub on your local machine."
            )
        },
    )
    ignore_mismatched_sizes: bool = field(
        default=False,
        metadata={"help": "Will enable to load a pretrained model whose head dimensions are different."},
    )


def main():
    # See all possible arguments in src/transformers/training_args.py
    # or by passing the --help flag to this script.
    # We now keep distinct sets of args, for a cleaner separation of concerns.

    parser = HfArgumentParser((ModelArguments, DataTrainingArguments, TrainingArguments))
    if len(sys.argv) == 2 and sys.argv[1].endswith(".json"):
        # If we pass only one argument to the script and it's the path to a json file,
        # let's parse it to get our arguments.
        model_args, data_args, training_args = parser.parse_json_file(json_file=os.path.abspath(sys.argv[1]))
    else:
        model_args, data_args, training_args = parser.parse_args_into_dataclasses()

    # Setup logging
    logging.basicConfig(
        format="%(asctime)s - %(levelname)s - %(name)s - %(message)s",
        datefmt="%m/%d/%Y %H:%M:%S",
        handlers=[logging.StreamHandler(sys.stdout)],
    )

    if training_args.should_log:
        # The default of training_args.log_level is passive, so we set log level at info here to have that default.
        transformers.utils.logging.set_verbosity_info()

    log_level = training_args.get_process_log_level()
    logger.setLevel(log_level)
    transformers.utils.logging.set_verbosity(log_level)
    transformers.utils.logging.enable_default_handler()
    transformers.utils.logging.enable_explicit_format()

    # Log on each process the small summary:
    logger.warning(
        f"Process rank: {training_args.local_process_index}, device: {training_args.device}, n_gpu: {training_args.n_gpu}, "
        + f"distributed training: {training_args.parallel_mode.value == 'distributed'}, 16-bits training: {training_args.fp16}"
    )
    logger.info(f"Training/evaluation parameters {training_args}")

    # Set seed before initializing model.
    set_seed(training_args.seed)

    # Initialize our dataset and prepare it for the audio classification task.
    raw_datasets = DatasetDict()
    raw_datasets["train"] = load_dataset(
        data_args.dataset_name,
        data_args.dataset_config_name,
        split=data_args.train_split_name,
        token=model_args.token,
        trust_remote_code=model_args.trust_remote_code,
    )
    raw_datasets["eval"] = load_dataset(
        data_args.dataset_name,
        data_args.dataset_config_name,
        split=data_args.eval_split_name,
        token=model_args.token,
        trust_remote_code=model_args.trust_remote_code,
    )

    if data_args.audio_column_name not in raw_datasets["train"].column_names:
        raise ValueError(
            f"--audio_column_name {data_args.audio_column_name} not found in dataset '{data_args.dataset_name}'. "
            "Make sure to set `--audio_column_name` to the correct audio column - one of "
            f"{', '.join(raw_datasets['train'].column_names)}."
        )

    if data_args.label_column_name not in raw_datasets["train"].column_names:
        raise ValueError(
            f"--label_column_name {data_args.label_column_name} not found in dataset '{data_args.dataset_name}'. "
            "Make sure to set `--label_column_name` to the correct text column - one of "
            f"{', '.join(raw_datasets['train'].column_names)}."
        )

    # Setting `return_attention_mask=True` is the way to get a correctly masked mean-pooling over
    # transformer outputs in the classifier, but it doesn't always lead to better accuracy
    feature_extractor = AutoFeatureExtractor.from_pretrained(
        model_args.feature_extractor_name or model_args.model_name_or_path,
        return_attention_mask=model_args.attention_mask,
        cache_dir=model_args.cache_dir,
        revision=model_args.model_revision,
        token=model_args.token,
        trust_remote_code=model_args.trust_remote_code,
    )

    # `datasets` takes care of automatically loading and resampling the audio,
    # so we just need to set the correct target sampling rate.
    raw_datasets = raw_datasets.cast_column(
        data_args.audio_column_name, datasets.features.Audio(sampling_rate=feature_extractor.sampling_rate)
    )

    model_input_name = feature_extractor.model_input_names[0]

    def train_transforms(batch):
        """Apply train_transforms across a batch."""
        subsampled_wavs = []
        for audio in batch[data_args.audio_column_name]:
            wav = random_subsample(
                audio["array"], max_length=data_args.max_length_seconds, sample_rate=feature_extractor.sampling_rate
            )
            subsampled_wavs.append(wav)
        inputs = feature_extractor(subsampled_wavs, sampling_rate=feature_extractor.sampling_rate)
        output_batch = {model_input_name: inputs.get(model_input_name)}
        output_batch["labels"] = list(batch[data_args.label_column_name])

        return output_batch

    def val_transforms(batch):
        """Apply val_transforms across a batch."""
        wavs = [audio["array"] for audio in batch[data_args.audio_column_name]]
        inputs = feature_extractor(wavs, sampling_rate=feature_extractor.sampling_rate)
        output_batch = {model_input_name: inputs.get(model_input_name)}
        output_batch["labels"] = list(batch[data_args.label_column_name])

        return output_batch

    # Prepare label mappings.
    # We'll include these in the model's config to get human readable labels in the Inference API.
    labels = raw_datasets["train"].features[data_args.label_column_name].names
    label2id, id2label = {}, {}
    for i, label in enumerate(labels):
        label2id[label] = str(i)
        id2label[str(i)] = label

    # Load the accuracy metric from the datasets package
    metric = evaluate.load("accuracy", cache_dir=model_args.cache_dir)

    # Define our compute_metrics function. It takes an `EvalPrediction` object (a namedtuple with
    # `predictions` and `label_ids` fields) and has to return a dictionary string to float.
    def compute_metrics(eval_pred):
        """Computes accuracy on a batch of predictions"""
        predictions = np.argmax(eval_pred.predictions, axis=1)
        return metric.compute(predictions=predictions, references=eval_pred.label_ids)

    config = AutoConfig.from_pretrained(
        model_args.config_name or model_args.model_name_or_path,
        num_labels=len(labels),
        label2id=label2id,
        id2label=id2label,
        finetuning_task="audio-classification",
        cache_dir=model_args.cache_dir,
        revision=model_args.model_revision,
        token=model_args.token,
        trust_remote_code=model_args.trust_remote_code,
    )
    model = AutoModelForAudioClassification.from_pretrained(
        model_args.model_name_or_path,
        from_tf=bool(".ckpt" in model_args.model_name_or_path),
        config=config,
        cache_dir=model_args.cache_dir,
        revision=model_args.model_revision,
        token=model_args.token,
        trust_remote_code=model_args.trust_remote_code,
        ignore_mismatched_sizes=model_args.ignore_mismatched_sizes,
    )

    # freeze the convolutional waveform encoder
    if model_args.freeze_feature_encoder:
        model.freeze_feature_encoder()

    if training_args.do_train:
        if data_args.max_train_samples is not None:
            raw_datasets["train"] = (
                raw_datasets["train"].shuffle(seed=training_args.seed).select(range(data_args.max_train_samples))
            )
        # Set the training transforms
        raw_datasets["train"].set_transform(train_transforms, output_all_columns=False)

    if training_args.do_eval:
        if data_args.max_eval_samples is not None:
            raw_datasets["eval"] = (
                raw_datasets["eval"].shuffle(seed=training_args.seed).select(range(data_args.max_eval_samples))
            )
        # Set the validation transforms
        raw_datasets["eval"].set_transform(val_transforms, output_all_columns=False)

    # Initialize our trainer
    trainer = Trainer(
        model=model,
        args=training_args,
        train_dataset=raw_datasets["train"] if training_args.do_train else None,
        eval_dataset=raw_datasets["eval"] if training_args.do_eval else None,
        compute_metrics=compute_metrics,
        processing_class=feature_extractor,
    )

    # Training
    if training_args.do_train:
        checkpoint = None
        if training_args.resume_from_checkpoint is not None:
            checkpoint = training_args.resume_from_checkpoint
        train_result = trainer.train(resume_from_checkpoint=checkpoint)
        trainer.save_model()
        trainer.log_metrics("train", train_result.metrics)
        trainer.save_metrics("train", train_result.metrics)
        trainer.save_state()

    # Evaluation
    if training_args.do_eval:
        metrics = trainer.evaluate()
        trainer.log_metrics("eval", metrics)
        trainer.save_metrics("eval", metrics)

    # Write model card and (optionally) push to hub
    kwargs = {
        "finetuned_from": model_args.model_name_or_path,
        "tasks": "audio-classification",
        "dataset": data_args.dataset_name,
        "tags": ["audio-classification"],
    }
    if training_args.push_to_hub:
        trainer.push_to_hub(**kwargs)
    else:
        trainer.create_model_card(**kwargs)


if __name__ == "__main__":
    main()