app.py

from __future__ import annotations
import gradio as gr

from datasets import load_dataset, load_metric, Audio, concatenate_datasets, Dataset
from transformers import Wav2Vec2CTCTokenizer, Wav2Vec2FeatureExtractor, Wav2Vec2Processor, Wav2Vec2ForCTC, TrainingArguments, Trainer
import json
import torch
from dataclasses import dataclass, field
from typing import Any, Dict, List, Optional, Union
import random
import argparse
import pandas as pd
import os
import multiprocess

import json
from typing import List, Optional
from transformers.tokenization_utils import PreTrainedTokenizer
from transformers.tokenization_utils_base import AddedToken

class Wav2Vec2CTCTokenizer(Wav2Vec2CTCTokenizer):
    
    def _decode(
        self,
        token_ids: list[int],
        skip_special_tokens: bool = False,
        clean_up_tokenization_spaces: Optional[bool] = None,
        group_tokens: bool = True,
        spaces_between_special_tokens: bool = False,
        output_word_offsets: Optional[bool] = False,
        output_char_offsets: Optional[bool] = False,
    ) -> str:
        """
        special _decode function is needed for Wav2Vec2Tokenizer because added tokens should be treated exactly the
        same as tokens of the base vocabulary and therefore the function `convert_tokens_to_string` has to be called on
        the whole token list and not individually on added tokens
        """
        filtered_tokens = self.convert_ids_to_tokens(token_ids, skip_special_tokens=skip_special_tokens)

        result = []
        for token in filtered_tokens:
            if skip_special_tokens and (
                token in self.all_special_ids or (token != self.pad_token and token in self.all_special_tokens)
            ):
                continue
            result.append(token)

        string_output = self.convert_tokens_to_string(
            result,
            group_tokens=group_tokens,
            spaces_between_special_tokens=spaces_between_special_tokens,
            output_word_offsets=output_word_offsets,
            output_char_offsets=output_char_offsets,
        )

        text = string_output["text"]

        clean_up_tokenization_spaces = (
            clean_up_tokenization_spaces
            if clean_up_tokenization_spaces is not None
            else self.clean_up_tokenization_spaces
        )
        if clean_up_tokenization_spaces:
            text = self.clean_up_tokenization(text)

        if output_word_offsets or output_char_offsets:
            return Wav2Vec2CTCTokenizerOutput(
                text=text,
                char_offsets=string_output["char_offsets"],
                word_offsets=string_output["word_offsets"],
            )
        else:
            return text


import torch
import warnings
from torch import nn                     # needed only if you add extra layers
from transformers import (
    Wav2Vec2ForCTC,                      # base model we extend
    Wav2Vec2Config,                      # type hinting & standalone instantiation
    Wav2Vec2Model,
    logging as hf_logging                # optional: nicer error messages
)

from transformers.utils import (
    auto_docstring,
)

from transformers.modeling_outputs import (
    CausalLMOutput,
)

class Wav2Vec2ForCTC24Heads(Wav2Vec2ForCTC):
    """
    Same encoder as Wav2Vec2ForCTC but with 24 parallel lm-heads and
    an aggregated CTC loss.

    Expected `labels` shape  :  (batch, 24, target_len)
    Returned `logits` shape :  (batch, 24, time, vocab_size)
    """

    def __init__(self, config, num_heads: int = 24, target_lang: Optional[str] = None):
        super().__init__(config)

        self.wav2vec2 = Wav2Vec2Model(config)
        self.dropout = nn.Dropout(config.final_dropout)

        self.target_lang = target_lang

        if config.vocab_size is None:
            raise ValueError(
                f"You are trying to instantiate {self.__class__} with a configuration that "
                "does not define the vocabulary size of the language model head. Please "
                "instantiate the model as follows: `Wav2Vec2ForCTC.from_pretrained(..., vocab_size=vocab_size)`. "
                "or define `vocab_size` of your model's configuration."
            )

        output_hidden_size = (
            config.output_hidden_size if hasattr(config, "add_adapter") and config.add_adapter else config.hidden_size
        )
        
        
        self.num_heads = num_heads

        # Replace the single head with a ModuleList of heads
        self.lm_head = nn.ModuleList(
            [nn.Linear(output_hidden_size, config.vocab_size) for _ in range(num_heads)]
        )

    def freeze_feature_extractor(self):
        """
        Calling this function will disable the gradient computation for the feature encoder so that its parameters will
        not be updated during training.
        """
        warnings.warn(
            "The method `freeze_feature_extractor` is deprecated and will be removed in Transformers v5. "
            "Please use the equivalent `freeze_feature_encoder` method instead.",
            FutureWarning,
        )
        self.freeze_feature_encoder()

    @auto_docstring
    def forward(
        self,
        input_values: Optional[torch.Tensor],
        attention_mask: Optional[torch.Tensor] = None,
        output_attentions: Optional[bool] = None,
        output_hidden_states: Optional[bool] = None,
        return_dict: Optional[bool] = None,
        labels: Optional[torch.Tensor] = None,
    ) -> Union[tuple, CausalLMOutput]:
        r"""
        labels (`torch.LongTensor` of shape `(batch_size, target_length)`, *optional*):
            Labels for connectionist temporal classification. Note that `target_length` has to be smaller or equal to
            the sequence length of the output logits. Indices are selected in `[-100, 0, ..., config.vocab_size - 1]`.
            All labels set to `-100` are ignored (masked), the loss is only computed for labels in `[0, ...,
            config.vocab_size - 1]`.
        """
        return_dict = return_dict if return_dict is not None else self.config.use_return_dict

        if labels is not None and labels.max() >= self.config.vocab_size:
            raise ValueError(f"Label values must be <= vocab_size: {self.config.vocab_size}")

        outputs = self.wav2vec2(
            input_values,
            attention_mask=attention_mask,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            return_dict=return_dict,
        )

        hidden_states = outputs[0]
        hidden_states = self.dropout(hidden_states) 

        logits = torch.stack(
            [head(hidden_states) for head in self.lm_head],   # list[B,T,V]
            dim=1                                             # -> (B, 24, T, V)
        )

        loss = None
        if labels is not None:

            # retrieve loss input_lengths from attention_mask
            attention_mask = (
                attention_mask if attention_mask is not None else torch.ones_like(input_values, dtype=torch.long)
            )
            input_lengths = self._get_feat_extract_output_lengths(attention_mask.sum(-1)).to(torch.long)

            loss_list = []
            for h in range(self.num_heads):
                # grab labels for this head: (B, target_len)
                
                lab = labels[:, h]

                # mask – targets for CTC must be 1-D
                # assuming that padded tokens are filled with -100
                # when not being attended to
                lab_mask = lab >= 0
                target_lengths = lab_mask.sum(-1)
                flat_targets   = lab.masked_select(lab_mask)
                

                log_probs = nn.functional.log_softmax(logits[:, h], dim=-1).transpose(0, 1)            # (T,B,V)


                with torch.backends.cudnn.flags(enabled=False):
                    head_loss = nn.functional.ctc_loss(
                        log_probs,
                        flat_targets,
                        input_lengths,
                        target_lengths,
                        blank=self.config.pad_token_id,
                        reduction="mean",          # per-head loss
                        zero_infinity=self.config.ctc_zero_infinity,
                    )
                
                loss_list.append(head_loss)

            loss = torch.stack(loss_list).mean()        # aggregate

            batch_preds = []                          # will become length B
            for b in range(logits.size(0)):
                head_preds = []                       # will become length 24
                for h in range(logits.size(1)):
                    ids = logits[b, h].argmax(dim=-1) # (T,)
                    head_preds.append(ids)            # accumulate each head
                head_preds = torch.stack(head_preds)  # (24, T)  ← “vector” of heads
                batch_preds.append(head_preds)

            batch_preds = torch.stack(batch_preds)    # (B, 24, T)
            

        if not return_dict:
            output = (logits,) + outputs[_HIDDEN_STATES_START_POSITION:]
            return ((loss,) + output) if loss is not None else output


        return CausalLMOutput(
            loss=loss, logits=logits, hidden_states=outputs.hidden_states, attentions=outputs.attentions
        )

from dataclasses import dataclass
from typing import Dict, List, Union
import torch
from transformers import Wav2Vec2Processor

@dataclass
class DataCollatorCTCWithPadding:
    """
    Data collator that will dynamically pad the inputs received.
    Args:
        processor (:class:`~transformers.Wav2Vec2Processor`)
            The processor used for proccessing the data.
        padding (:obj:`bool`, :obj:`str` or :class:`~transformers.tokenization_utils_base.PaddingStrategy`, `optional`, defaults to :obj:`True`):
            Select a strategy to pad the returned sequences (according to the model's padding side and padding index)
            among:
            * :obj:`True` or :obj:`'longest'`: Pad to the longest sequence in the batch (or no padding if only a single
              sequence if provided).
            * :obj:`'max_length'`: Pad to a maximum length specified with the argument :obj:`max_length` or to the
              maximum acceptable input length for the model if that argument is not provided.
            * :obj:`False` or :obj:`'do_not_pad'` (default): No padding (i.e., can output a batch with sequences of
              different lengths).
        max_length (:obj:`int`, `optional`):
            Maximum length of the ``input_values`` of the returned list and optionally padding length (see above).
        max_length_labels (:obj:`int`, `optional`):
            Maximum length of the ``labels`` returned list and optionally padding length (see above).
        pad_to_multiple_of (:obj:`int`, `optional`):
            If set will pad the sequence to a multiple of the provided value.
            This is especially useful to enable the use of Tensor Cores on NVIDIA hardware with compute capability >=
            7.5 (Volta).
    """
    processor: Wav2Vec2Processor
    padding: Union[bool, str] = True
    max_length: Optional[int] = None
    max_length_labels: Optional[int] = None
    pad_to_multiple_of: Optional[int] = None
    pad_to_multiple_of_labels: Optional[int] = None

    def __call__(self, features: List[Dict[str, Union[List[int], torch.Tensor]]]) -> Dict[str, torch.Tensor]:
        # Split inputs and labels since they have to be of different lengths
        # and need different padding methods
        input_features = [{"input_values": feature["input_values"]} for feature in features]
        label_features = [{"input_ids": feature["labels"]} for feature in features]

        batch = self.processor.pad(
            input_features,
            padding=self.padding,
            max_length=self.max_length,
            pad_to_multiple_of=self.pad_to_multiple_of,
            return_tensors="pt",
            )
        with self.processor.as_target_processor():
            labels_batch = self.processor.pad(
                label_features,
                padding=self.padding,
                max_length=self.max_length_labels,
                pad_to_multiple_of=self.pad_to_multiple_of_labels,
                return_tensors="pt",
                )

        # Replace padding with -100 to ignore loss correctly
        labels = labels_batch["input_ids"].masked_fill(labels_batch.attention_mask.ne(1), -100)

        batch["labels"] = labels

        return batch

@dataclass
class DataCollator24CTC(DataCollatorCTCWithPadding):
    processor: Wav2Vec2Processor
    padding: Union[bool, str] = True
    max_length: Optional[int] = None
    max_length_labels: Optional[int] = None
    pad_to_multiple_of: Optional[int] = None
    pad_to_multiple_of_labels: Optional[int] = None
    num_heads: int = 24

    def __call__(self, features: List[Dict[str, Union[List[int], torch.Tensor]]]) -> Dict[str, torch.Tensor]:
        # Split inputs and labels since they have to be of different lengths
        # and need different padding methods
        input_features = [{"input_values": feature["input_values"]} for feature in features]
        
        batch = self.processor.pad(
            input_features,
            padding=self.padding,
            max_length=self.max_length,
            pad_to_multiple_of=self.pad_to_multiple_of,
            return_tensors="pt",
            )

        all_labels = []
        for h in range(self.num_heads):
            label_features_h = [{"input_ids": feature["labels"][h]} for feature in features]
            with self.processor.as_target_processor():
                labels_batch = self.processor.pad(
                    label_features_h,
                    padding=self.padding,
                    max_length=self.max_length_labels,
                    pad_to_multiple_of=self.pad_to_multiple_of_labels,
                    return_tensors="pt",
                )
            padded_ids = labels_batch["input_ids"].masked_fill(labels_batch.attention_mask.ne(1), -100)
            all_labels.append(padded_ids)
        
        # Stack to (num_heads, batch, seq_len) -> then permute to (batch, num_heads, seq_len)
        labels = torch.stack(all_labels).permute(1, 0, 2)

        batch['labels'] = labels

        return batch

import os
import json
import random
from pathlib import Path
from typing import List

import numpy as np
import torchaudio, torchaudio.transforms as T

from datasets import Dataset, Features, Sequence, Value, load_from_disk, concatenate_datasets



# ------------------------------------------------------------------
# 1)  Audio helpers
# ------------------------------------------------------------------
def load_and_standardise(path: str | Path, target_sr: int = 16_000) -> list[float]:
    """
    • Loads `path` with torchaudio
    • Resamples to `target_sr` if necessary
    • Converts to mono (mean over channels)
    • Standardises to zero-mean / unit-var
    • Returns a *Python list* of floats so it is JSON-serialisable
    """
    
    array, sampling_rate = torchaudio.load(path)
    
    if sampling_rate != 16000:
        array = T.Resample(sampling_rate, 16000)(array)
    array = array.numpy()
    array = array.mean(axis=0)

    return array.tolist()

# --------------------------------------------------------------
# 2)  Streaming readers (JSON array or NDJSON)
# --------------------------------------------------------------
def iter_entries(json_path: str | Path):
    """
    Yield entries from either a single JSON array file or an NDJSON file.
    Streaming line-by-line for NDJSON so we never hold the whole file in RAM.
    """
    p = Path(json_path)
    txt = p.read_text(encoding="utf-8")
    try:
        data = json.loads(txt)
        if isinstance(data, list):
            for obj in data:
                yield obj
        else:
            yield data
    except json.JSONDecodeError:
        for ln in txt.splitlines():
            ln = ln.strip()
            if ln:
                yield json.loads(ln)


# --------------------------------------------------------------
# 3)  Stage-1: process one source once and cache to disk (Arrow)
# --------------------------------------------------------------
def preprocess_source_to_cache(
    json_path: str | Path,
    processor: Wav2Vec2Processor,
    cache_root: str | Path,
    source_tag: str,            # any stable name (e.g. 'en', 'jp', 'doreco-an')
) -> Path:
    """
    Stream over entries in json_path, fully decode audio and convert labels to IDs.
    Save as a HuggingFace dataset to disk (memory-mapped Arrow).
    Returns the folder path created by `save_to_disk()`.
    """
    cache_root = Path(cache_root)
    cache_root.mkdir(parents=True, exist_ok=True)
    save_path = cache_root / f"cache_{source_tag}"

    save_path.mkdir(parents=True, exist_ok=True)

    # If cache already exists, skip reprocessing to save time.
    if (save_path / "dataset_info.json").exists():
        print(f"[cache] Using existing cache: {save_path}")
        return save_path
    else:
        if save_path.exists():
            import shutil; shutil.rmtree(save_path)
        save_path.mkdir(parents=True, exist_ok=True)

    def row_generator():
        for obj in iter_entries(json_path):
            # Expect {"path": "...", "ipa": <matrix or whatever your build used>}
            ipa_matrix = obj.get("ipa", [])
            if not ipa_matrix:
                continue

            # your original: matrix was [segments x 22]; you transposed and stringified
            transpose = [list(row) for row in zip(*ipa_matrix)]
            transpose_str = [[str(tok) for tok in head] for head in transpose]

            # Decode audio once (as requested)
            audio = load_and_standardise(obj["path"])
            # Cast to float32 for Arrow efficiency
            audio = np.asarray(audio, dtype=np.float32)

            # Convert labels to IDs once (keep nested per-head if your collator expects it)
            label_ids: List[List[int]] = []
            for head in transpose_str:
                with processor.as_target_processor():
                    ids = processor(head).input_ids
                # ids might be [[id]]; unwrap if needed:
                ids = [tok[0] if isinstance(tok, list) else tok for tok in ids]
                label_ids.append(ids)

            yield {
                "input_values": audio,      # variable length float32
                "labels": label_ids,        # list[list[int]]
                "source": source_tag,       # keep origin
            }

    # Features: variable-length floats + nested variable-length ints
    features = Features({
        "input_values": Sequence(Value("float32")),
        "labels":       Sequence(Sequence(Value("int32"))),
        "source":       Value("string"),
    })

    rows, chunks = [], []
    for row in row_generator():              # <- your existing generator
        rows.append(row)
        if len(rows) >= 5_000:               # tune shard size to your RAM
            chunks.append(Dataset.from_list(rows))
            rows = []                        # free current chunk

    if rows:                                 # tail of the stream
        chunks.append(Dataset.from_list(rows))

    ds = concatenate_datasets(chunks)        # single Dataset object
    ds.save_to_disk(save_path.as_posix())    # writes Arrow to local FS
    print(f"[cache] Wrote {len(ds)} rows → {save_path}")
    return save_path


# --------------------------------------------------------------
# 4)  Stage-2: build a weighted dataset from cached sources
#     (no re-decoding, no in-RAM duplication)
# --------------------------------------------------------------
def build_weighted_dataset_from_cache(
    cache_paths: list[str | Path],
    percentages: list[float],
    *,
    seed: int = 42
) -> Dataset:
    """
    For each cached source dataset:
      pct >= 100 → full copies n_full times + fractional random subset
      pct <  100 → fractional random subset only
    All operations are Arrow-backed (memory-mapped), so no RAM blow-ups.
    """
    assert len(cache_paths) == len(percentages)
    rng = random.Random(seed)

    per_source_weighted = []

    for cache_path, pct in zip(cache_paths, percentages):
        ds = load_from_disk(str(cache_path))
        N  = len(ds)
        if N == 0 or pct <= 0:
            continue

        n_full = int(pct // 100)
        frac   = (pct % 100) / 100.0
        n_frac = round(N * frac)

        parts = []

        # Full copies: concatenate the same dataset handle N times (no decode)
        if n_full > 0:
            parts.extend([ds] * n_full)

        # Fractional random subset (no decode)
        if n_frac > 0:
            idxs = rng.sample(range(N), n_frac)
            parts.append(ds.select(idxs))

        if not parts:
            continue

        ds_weighted = parts[0] if len(parts) == 1 else concatenate_datasets(parts)
        per_source_weighted.append(ds_weighted)
        print(f"[weight] {cache_path}  →  {len(ds_weighted)} rows "
              f"(full×{n_full} + frac {n_frac}/{N})")

    # Final training set = concat of all weighted sources
    if not per_source_weighted:
        raise RuntimeError("No data after weighting.")
    train_ds = per_source_weighted[0] if len(per_source_weighted) == 1 \
               else concatenate_datasets(per_source_weighted)

    # Optional: shuffle once for training
    train_ds = train_ds.shuffle(seed=seed)
    print(f"[train] Total rows: {len(train_ds)}")
    return train_ds


vocab_file = "dummy_vocab.json"

feature_extractor = Wav2Vec2FeatureExtractor(feature_size=1,
                                                 sampling_rate=16_000,
                                                 padding_value=0.0,
                                                 do_normalize=True,
                                                 return_attention_mask=True)

tokenizer_ipa = Wav2Vec2CTCTokenizer("./{}".format(vocab_file),
                                         unk_token="[UNK]",
                                         pad_token="[PAD]",
                                         word_delimiter_token="|")

processor_ipa = Wav2Vec2Processor(feature_extractor=feature_extractor,
                                      tokenizer=tokenizer_ipa)

import numpy as np
from phd_model.phonetics.ipa import symbol_to_descriptor, to_symbol
from phd_model.model.wav2vec2 import Wav2Vec2
from transformers import Wav2Vec2Processor
import torchaudio, torchaudio.transforms as T
from torchinfo import summary
import torch
import re

ckpt_dir   = "Eripsa/asr-basque-model"


# Get device
device = "cuda" if torch.cuda.is_available() else "cpu"

# Load model from Huggingface hub
wav2vec2 = Wav2Vec2ForCTC24Heads.from_pretrained(ckpt_dir)
processor = Wav2Vec2Processor.from_pretrained(ckpt_dir)
wav2vec2.to(device)
wav2vec2.eval()

# Print model summary for batch_size 1 and a single second of audio samples
summary(wav2vec2, input_size=(1, 16_000), depth=8, device=device)

# Create new random audio (you can load your own audio here to get actual predictions)
#rand_audio = np.random.rand(1, 16_000)

def generate_tensor(audio_path: str):

    #audio_path = "/workspace/F5-TTS/data/marrazki_custom/wavs/segment_3153.wav"
    
    #rand_audio = load_and_standardise(audio_path)
    #rand_audio, sr = torchaudio.load(audio_path)
    
    array, sampling_rate = torchaudio.load(audio_path)
    
    if sampling_rate != 16000:
        array = T.Resample(sampling_rate, 16000)(array)
    array = array.numpy()
    array = array.mean(axis=0, keepdims=True)
    
    # Create torch tensor, move to device and feed the model
    array = torch.tensor(
        array,
        dtype=torch.float,
        device=device,
    )
    
    print(array)
    with torch.no_grad():
        out = wav2vec2(array)
        logits = out.logits
    
    # regular–expression that finds either the 2‑char token "-1"
    # OR any single char in 0,1,|
    token_re = re.compile(r"-1|[01\|]")
    
    batch_tokens = []                       # final matrix  (B × 24)
    
    for b in range(logits.size(0)):
        head_tokens = []                    # 24 rows for this utterance
    
        for h in range(logits.size(1)):
            # ---------- 1) arg‑max & CTC collapse → string ----------
            ids = logits[b, h].argmax(dim=-1).cpu().tolist()
    
            #text = processor._decode(
            #    ids,
            #)
            text = tokenizer_ipa._decode(token_ids = ids)
    
            # ---------- 2) split the string into symbols ----------
            symbols = token_re.findall(text)    # e.g. ['-1', '1', '-1', '-1', …]
    
            head_tokens.append(symbols)
    
        batch_tokens.append(head_tokens)
    
    batch_data = [[[int(val) for val in row] for row in matrix] for matrix in batch_tokens]
    
    print(f"batch_data : {batch_data}")
    
    # Convert to a PyTorch tensor
    batch_tensor = torch.tensor(batch_data)

    return batch_tensor


"""
vector2ipa.py
=============

Map articulatory feature vectors (shape ≡ [*, 22]) to IPA symbols.

* If a row is an **exact** match for a symbol’s feature vector,
  return that symbol.

* Otherwise compute the Levenshtein distance between the input
  vector and every known IPA vector and choose the symbol with
  the minimum distance.

Requires:  panphon  (pip install panphon)
           numpy    (only for dtype / convenience, but any tensor works)

Author: <you>
"""

import numpy as np
from typing import Iterable, List, Sequence, Tuple

import panphon                       # -- main feature database
from panphon.segment import Segment  # convenient Segment wrapper


# --------------------------------------------------------------------
# helpers
# --------------------------------------------------------------------
def _levenshtein(a: Sequence[int], b: Sequence[int]) -> int:
    """Classic O(m·n) Levenshtein distance for two sequences of ints."""
    m, n = len(a), len(b)
    prev = list(range(n + 1))
    curr = [0] * (n + 1)

    for i in range(1, m + 1):
        curr[0] = i
        for j in range(1, n + 1):
            cost = 0 if a[i - 1] == b[j - 1] else 1
            curr[j] = min(
                curr[j - 1] + 1,     # insertion
                prev[j] + 1,         # deletion
                prev[j - 1] + cost   # substitution
            )
        prev, curr = curr, prev      # reuse buffers
    return prev[n]

def _as_int_vector(raw):
    """Convert a PanPhon vector (numeric or ±0 string form) to a tuple of ints."""
    if isinstance(raw[0], int):
        return tuple(int(x) for x in raw)
    map_sym = {'+': 1, '-': -1, '0': 0}
    return tuple(map_sym[x] for x in raw)


def _build_inventory(ft):
    ipa_syms, ipa_vecs = [], []

    # ❶  Whatever version we’re on, get *something* iterable
    seg_iter = getattr(ft, "segments", None) or getattr(ft, "_segments", None)
    if seg_iter is None:
        raise RuntimeError("Can't locate segment inventory on this PanPhon version.")

    for item in seg_iter:
        # ❷  Newer PanPhon:  item = (symbol:str, Segment)
        #     Older PanPhon:  item = symbol:str
        symbol = item[0] if isinstance(item, tuple) else item

        # ❸  Grab the canonical 22-feature vector
        try:
            raw = ft.segment_to_vector(symbol)          # post-0.22
        except TypeError:
            raw = ft.segment_to_vector(symbol, True)    # ≤0.21 fallback

        if raw is None:                                 # skip tones, length marks…
            continue
        ipa_syms.append(symbol)
        ipa_vecs.append(_as_int_vector(raw))            # → tuple[int, …]

    return ipa_syms, ipa_vecs


# --------------------------------------------------------------------
# public API
# --------------------------------------------------------------------
def vectors_to_ipa(
    tensor: Iterable[Sequence[int]],
    ft: panphon.FeatureTable | None = None,
) -> List[str]:
    """
    Parameters
    ----------
    tensor
        Any iterable yielding rows of 22 ints (values −1/0/+1).

        Works with:
            * list[list[int]]
            * numpy.ndarray  (shape [N,22] or [22])
            * torch.Tensor   (dtype=torch.int8 / int16 / int32)
            * etc.

    ft
        Optionally pass in a pre-constructed FeatureTable so you
        don’t pay the I/O cost repeatedly.

    Returns
    -------
    List[str]
        The IPA symbol that best matches each input row.
    """
    # 🗄️  Load feature database exactly once
    ft = ft or panphon.FeatureTable()
    ipa_syms, ipa_vecs = _build_inventory(ft)

    # ⚡  Small dict for constant-time exact look-ups
    exact_lookup = {v: s for s, v in zip(ipa_syms, ipa_vecs)}

    results: List[str] = []
    for row in tensor:
        vec = tuple(int(x) for x in row)     # normalise dtype

        # 1️⃣  Exact hit?
        if vec in exact_lookup:
            results.append(exact_lookup[vec])
            continue

        # 2️⃣  Nearest neighbour by Levenshtein distance
        best_sym, best_dist = None, float("inf")
        for ref_vec, sym in zip(ipa_vecs, ipa_syms):
            d = _levenshtein(vec, ref_vec)
            if d < best_dist:
                best_dist, best_sym = d, sym
                if d == 0:                   # early exit
                    break
        results.append(f"{best_sym}")

    # Print results (per brief) and return in case caller needs them
    symbols_str = " ".join(results)
    #print(symbols_str)
    return symbols_str


def transcribe_to_ipa(audio_path):
    batch_tensor = generate_tensor(audio_path)

    batch_tensor = batch_tensor.squeeze(0)

    symbols = vectors_to_ipa(batch_tensor.t())
    
    return symbols

demo = gr.Interface(fn=transcribe_to_ipa, inputs=gr.Audio(type="filepath"), outputs="text")
demo.launch(share=True)