#!/usr/bin/env python3
from datasets import load_dataset, load_metric, Audio
from transformers import AutoModelForCTC, AutoProcessor, Wav2Vec2Processor
import torch
import re

lang = "sv-SE"
model_id = "./xls-r-300m-sv"

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

dataset = load_dataset("mozilla-foundation/common_voice_7_0", lang, split="test", use_auth_token=True)
wer = load_metric("wer")

dataset = dataset.cast_column("audio", Audio(sampling_rate=16_000))

model = AutoModelForCTC.from_pretrained(model_id).to(device)
processor = AutoProcessor.from_pretrained(model_id)


chars_to_ignore_regex = '[,?.!\-\;\:\"“%‘”�—’…–]'  # change to the ignored characters of your fine-tuned model


def map_to_pred(batch):
    input_values = processor(batch["audio"]["array"], return_tensors="pt", padding="longest", sampling_rate=16_000).input_values

    with torch.no_grad():
        logits = model(input_values.to(device)).logits

    if processor.__class__.__name__ == "Wav2Vec2Processor":
        predicted_ids = torch.argmax(logits, dim=-1)
        transcription = processor.batch_decode(predicted_ids)[0]
    else:
        transcription = processor.batch_decode(logits.cpu().numpy()).text[0]

    batch["transcription"] = transcription
    batch["text"] = re.sub(chars_to_ignore_regex, "", batch["sentence"].lower())
    return batch


result = dataset.map(map_to_pred, remove_columns=["audio"])

wer_result = wer.compute(references=result["text"], predictions=result["transcription"])

print("WER", wer_result)