tts.py

import os
import re
import time

import numpy as np
import requests
import torch
from typing import Optional, Tuple

from TTS.tts.configs.xtts_config import XttsConfig
from TTS.tts.models.xtts import Xtts
from TTS.tts.layers.xtts.tokenizer import VoiceBpeTokenizer, basic_cleaners
from coqpit import Coqpit
from huggingface_hub import hf_hub_download, hf_hub_url
from tqdm import tqdm


def download_file_with_progress(url: str, destination: str):
    """
    Downloads a file from a web URL with a progress bar.
    """
    # Streaming GET request
    response = requests.get(url, stream=True)

    # Total size in bytes, set to zero if missing
    total_size = int(response.headers.get('content-length', 0))

    # Using tqdm to display progress
    with open(destination, 'wb') as file, tqdm(desc=destination, total=total_size, unit='B', unit_scale=True,
                                               unit_divisor=1024) as bar:
        for data in response.iter_content(chunk_size=1024):
            size = file.write(data)
            bar.update(size)


class VoiceBambaraTextPreprocessor:
    def preprocess_batch(self, texts):
        return [self.preprocess(text) for text in texts]

    def preprocess(self, text: str) -> str:
        text = text.lower()
        text = self.expand_number(text)
        text = self.transliterate_bambara(text)

        return text

    def transliterate_bambara(self, text):
        """
        Transliterate Bambara text using a specified mapping of special characters.

        Parameters:
        - text (str): The original Bambara text.

        Returns:
        - str: The transliterated text.
        """
        bambara_transliteration = {
            'ɲ': 'ny',
            'ɛ': 'è',
            'ɔ': 'o',
            'ŋ': 'ng',
            'ɟ': 'j',
            'ʔ': "'",
            'ɣ': 'gh',
            'ʃ': 'sh',
            'ߒ': 'n',
            'ߎ': "u",
        }

        # Perform the transliteration
        transliterated_text = "".join(bambara_transliteration.get(char, char) for char in text)

        return transliterated_text

    def expand_number(self, text):
        """
        Normalize Bambara text for TTS by replacing numerical figures with their word equivalents.

        Args:
        text (str): The text to be normalized.

        Returns:
        str: The normalized Bambara text.
        """

        # A regex pattern to match all numbers
        number_pattern = re.compile(r'\b\d+\b')

        # Function to replace each number with its Bambara text
        def replace_number_with_text(match):
            number = int(match.group())
            return self.number_to_bambara(number)

        # Replace each number in the text with its Bambara word equivalent
        normalized_text = number_pattern.sub(replace_number_with_text, text)

        return normalized_text

    def number_to_bambara(self, n):

        """
        Convert a number into its textual representation in Bambara using recursion.
        Args:
        n (int): The number to be converted.
        Returns:
        str: The number expressed in Bambara text.
        Examples:
        >>> number_to_bambara(123)
        'kɛmɛ ni mugan ni saba'
        Notes:
        This function assumes that 'n' is a non-negative integer.
        """

        # Bambara numbering rules
        units = ["", "kɛlɛn", "fila", "saba", "naani", "duuru", "wɔrɔ", "wòlonwula", "sɛɛgin", "kɔnɔntɔn"]
        tens = ["", "tan", "mugan", "bisaba", "binaani", "biduuru", "biwɔrɔ", "biwòlonfila", "bisɛɛgin", "bikɔnɔntɔn"]
        hundreds = ["", "kɛmɛ"]
        thousands = ["", "waga"]
        millions = ["", "milyɔn"]

        # Handle zero explicitly
        if n == 0:
            return ""  # bambara does not support zero

        if n < 10:
            return units[n]
        elif n < 100:
            return tens[n // 10] + (" ni " + self.number_to_bambara(n % 10) if n % 10 > 0 else "")
        elif n < 1000:
            return hundreds[1] + (" " + self.number_to_bambara(n // 100) if n >= 200 else "") + (
                " ni " + self.number_to_bambara(n % 100) if n % 100 > 0 else "")
        elif n < 1_000_000:
            return thousands[1] + " " + self.number_to_bambara(n // 1000) + (
                " ni " + self.number_to_bambara(n % 1000) if n % 1000 > 0 else "")
        else:
            return millions[1] + " " + self.number_to_bambara(n // 1_000_000) + (
                " ni " + self.number_to_bambara(n % 1_000_000) if n % 1_000_000 > 0 else "")


class BambaraTokenizer(VoiceBpeTokenizer):
    """
    A tokenizer for the Bambara language that extends the VoiceBpeTokenizer.

    Attributes:
        preprocessor: An instance of VoiceBambaraTextPreprocessor for text preprocessing.
        char_limits: A dictionary to hold character limits for languages.
    """

    def __init__(self, vocab_file: Optional[str] = None):
        """
        Initializes the BambaraTokenizer with a given vocabulary file.

        Args:
            vocab_file: The path to the vocabulary file, defaults to None.
        """
        super().__init__(vocab_file)
        self.preprocessor = VoiceBambaraTextPreprocessor()
        self.char_limits['bm'] = 200  # Set character limit for Bambara language

    def preprocess_text(self, txt: str, lang: str) -> str:
        """
        Preprocesses the input text based on the language.

        Args:
            txt: The text to preprocess.
            lang: The language code of the text.

        Returns:
            The preprocessed text.
        """
        # Delegate preprocessing to the parent class for non-Bambara languages
        if lang != "bm":
            return super().preprocess_text(txt, lang)

        # Apply Bambara-specific preprocessing
        txt = self.preprocessor.preprocess(txt)
        txt = basic_cleaners(txt)
        return txt


class BambaraXtts(Xtts):
    """
    A class for the Bambara language that extends the Xtts class.

    Attributes:
        tokenizer: An instance of BambaraTokenizer.
    """

    def __init__(self, config: Coqpit):
        """
        Initializes the BambaraXtts with the provided configuration.

        Args:
            config: An instance of Coqpit containing configuration settings.
        """
        super().__init__(config)
        self.tokenizer = BambaraTokenizer()  # Initialize tokenizer for Bambara
        self.init_models()

    @classmethod
    def init_from_config(cls, config: "XttsConfig", **kwargs) -> "BambaraXtts":
        """
        Class method to create an instance of BambaraXtts from a configuration object.

        Args:
            config: An instance of XttsConfig containing configuration settings.
            **kwargs: Additional keyword arguments.

        Returns:
            An instance of BambaraXtts.
        """
        return cls(config)


class BambaraTTS:
    """
    Bambara Text-to-Speech (TTS) class that initializes and uses a TTS model for the Bambara language.

    Attributes:
        language_code (str): The ISO language code for Bambara.
        checkpoint_repo_or_dir (str): URL or local path to the model checkpoint directory.
        local_dir (str): The directory to store downloaded checkpoints.
        paths (dict): A dictionary of paths to model components.
        config (XttsConfig): Configuration object for the TTS model.
        model (BambaraXtts): The TTS model instance.
    """

    def __init__(self, checkpoint_repo_or_dir: str, local_dir: Optional[str] = None):
        """
        Initialize the BambaraTTS instance.

        Args:
            checkpoint_repo_or_dir: A string that represents either a Hugging Face hub repository
                                    or a local directory where the TTS model checkpoint is located.
            local_dir: An optional string representing a local directory path where model checkpoints
                       will be downloaded. If not specified, a default local directory is used based
                       on `checkpoint_repo_or_dir`.

        The initialization process involves setting up local directories for model components,
        ensuring the model checkpoint is available, and loading the model configuration and tokenizer.
        """

        # Set the language code for Bambara
        self.language_code = 'bm'

        # Store the checkpoint location and local directory path
        self.checkpoint_repo_or_dir = checkpoint_repo_or_dir
        # If no local directory is provided, use the default based on the checkpoint
        self.local_dir = local_dir if local_dir else self.default_local_dir(checkpoint_repo_or_dir)

        # Initialize the paths for model components
        self.paths = self.init_paths(self.local_dir)

        # Ensure the model checkpoint is available locally
        self.ensure_checkpoint_is_downloaded()

        # Load the model configuration from a JSON file
        self.config = XttsConfig()
        self.config.load_json(self.paths['config.json'])

        # Initialize the TTS model with the loaded configuration
        self.model = BambaraXtts(self.config)

        # Set up the tokenizer for the model, using the vocabulary file path
        self.model.tokenizer = BambaraTokenizer(vocab_file=self.paths['vocab.json'])

        # Load the model checkpoint into the initialized model
        self.model.load_checkpoint(
            self.config,
            vocab_path="fake_vocab.json",
            # The 'fake_vocab.json' is specified because the base model class might
            # attempt to override our tokenizer if a vocab file is present
            checkpoint_dir=self.local_dir,
            # use_deepspeed=torch.cuda.is_available()  # Utilize DeepSpeed if CUDA is available
            use_deepspeed=False # disable because make it fails on huggingface space
        )

        # Move the model to GPU if CUDA is available
        if torch.cuda.is_available():
            self.model.cuda()

        self.log_tokenizer()

    def ensure_checkpoint_is_downloaded(self):
        """
        Ensures that the model checkpoint is downloaded and available locally.
        """
        if os.path.exists(self.checkpoint_repo_or_dir):
            return

        os.makedirs(self.local_dir, exist_ok=True)
        self.log("Downloading checkpoint from the hub...")

        for filename, filepath in self.paths.items():
            if os.path.exists(filepath):
                self.log(f"File {filepath} already exists. Skipping...")
                continue

            file_url = hf_hub_url(repo_id=self.checkpoint_repo_or_dir, filename=filename)
            self.log(f"Downloading {filename} from {file_url}")
            download_file_with_progress(file_url, filepath)

        self.log("Checkpoint downloaded successfully!")

    def default_local_dir(self, checkpoint_repo_or_dir: str) -> str:
        """
        Generates a default local directory path for storing the model checkpoint.

        Args:
            checkpoint_repo_or_dir: The original checkpoint repository or directory path.

        Returns:
            The default local directory path.
        """
        if os.path.exists(checkpoint_repo_or_dir):
            return checkpoint_repo_or_dir

        model_path = f"models--{checkpoint_repo_or_dir.replace('/', '--')}"
        local_dir = os.path.join(os.path.expanduser('~'), "bambara_tts", model_path)
        return local_dir.lower()

    @staticmethod
    def init_paths(local_dir: str) -> dict:
        """
        Initializes paths to various model components based on the local directory.

        Args:
            local_dir: The local directory where model components are stored.

        Returns:
            A dictionary with keys as component names and values as file paths.
        """
        components = ['model.pth', 'config.json', 'vocab.json', 'dvae.pth', 'mel_stats.pth']
        return {name: os.path.join(local_dir, name) for name in components}

    def text_to_speech(
            self,
            text: str,
            speaker_reference_wav_path: Optional[str] = None,
            temperature: Optional[float] = 0.1,
            enable_text_splitting: bool = False
    ) -> Tuple[int, torch.Tensor]:
        """
        Converts text into speech audio.

        Args:
            text: The input text to be converted into speech.
            speaker_reference_wav_path: A path to a reference WAV file for the speaker.
            temperature: The temperature parameter for sampling.
            enable_text_splitting: Flag to enable or disable text splitting.

        Returns:
            A tuple containing the sampling rate and the generated audio tensor.
        """
        if speaker_reference_wav_path is None:
            speaker_reference_wav_path = "./audios/male_2.wav"
            self.log("Using default speaker reference ./audios/male_2.wav.")

        self.log("Computing speaker latents...")
        gpt_cond_latent, speaker_embedding = self.model.get_conditioning_latents(
            audio_path=[speaker_reference_wav_path]
        )

        self.log("Starting inference...")
        start_time = time.time()
        out = self.model.inference(
            text,
            self.language_code,
            gpt_cond_latent,
            speaker_embedding,
            temperature=temperature,
            enable_text_splitting=enable_text_splitting
        )
        end_time = time.time()

        audio = torch.tensor(out["wav"]).unsqueeze(0).cpu()
        sampling_rate = self.config.model_args.output_sample_rate

        self.log(f"Speech generated in {end_time - start_time:.2f} seconds.")

        return sampling_rate, audio

    def log(self, message: str):
        """
        Logs a message to the console with a uniform format.

        Args:
            message: The message to be logged.
        """
        print(f"[BambaraTTS] {message}")

    def log_tokenizer(self):
        """
        Logs the tokenizer information.
        """
        self.log(f"Tokenizer: {self.model.tokenizer}")