import gradio as gr
import os, uuid, re, tempfile
from pydub import AudioSegment, silence

# ----------------------------------
# Utils
# ----------------------------------
def clean_name(path, ext):
    name = re.sub(r'[^a-zA-Z0-9]+', '_', os.path.basename(path))
    return f"{name}_{uuid.uuid4().hex[:6]}.{ext}"

# ----------------------------------
# Convert to WAV (FAST PROCESSING)
# ----------------------------------
def ensure_wav(path):
    if path.lower().endswith(".wav"):
        return path

    audio = AudioSegment.from_file(path)
    audio = audio.set_channels(1)

    tmp = tempfile.gettempdir()
    wav_path = os.path.join(tmp, clean_name(path, "wav"))
    audio.export(wav_path, format="wav")
    return wav_path

# ----------------------------------
# SAFE Silence Removal
# ----------------------------------
def remove_silence_safe(path, keep_ms=250):
    audio = AudioSegment.from_wav(path)

    silence_thresh = audio.dBFS - 22

    chunks = silence.split_on_silence(
        audio,
        min_silence_len=350,
        silence_thresh=silence_thresh,
        keep_silence=keep_ms
    )

    if not chunks:
        return path

    out = AudioSegment.empty()
    for c in chunks:
        out += c.fade_in(20).fade_out(20)

    out_path = os.path.join(
        tempfile.gettempdir(),
        clean_name(path, "wav")
    )
    out.export(out_path, format="wav")
    return out_path

# ----------------------------------
# Duration
# ----------------------------------
def duration(path):
    return len(AudioSegment.from_wav(path)) / 1000

# ----------------------------------
# Main
# ----------------------------------
def process_audio(audio_file, keep_seconds):
    keep_ms = int(max(keep_seconds, 0.25) * 1000)

    wav = ensure_wav(audio_file)
    before = duration(wav)

    cleaned = remove_silence_safe(wav, keep_ms)
    after = duration(cleaned)

    # Export final MP3 (user friendly)
    final_mp3 = cleaned.replace(".wav", ".mp3")
    AudioSegment.from_wav(cleaned).export(final_mp3, format="mp3")

    info = (
        f"Old Duration : {before:.2f}s\n"
        f"New Duration : {after:.2f}s\n"
        f"Silence Removed : {before - after:.2f}s"
    )

    return final_mp3, final_mp3, info

# ----------------------------------
# UI
# ----------------------------------
with gr.Blocks(title="Fast Silence Remover") as demo:
    gr.Markdown(
        "## ⚡ Fast MP3/WAV Silence Remover (No Word Loss)"
    )

    with gr.Row():
        with gr.Column():
            audio = gr.Audio(
                type="filepath",
                sources=["upload"],
                label="Upload MP3 or WAV"
            )

            keep = gr.Number(
                value=0.25,
                label="Keep Silence (seconds)"
            )

            btn = gr.Button("Remove Silence")

        with gr.Column():
            out_audio = gr.Audio(label="Processed Audio")
            out_file = gr.File(label="Download")
            info = gr.Textbox(label="Info")

    btn.click(
        process_audio,
        [audio, keep],
        [out_audio, out_file, info]
    )

demo.queue().launch()