import gradio as gr
import numpy as np
import wave
import os
from pydub import AudioSegment

# Function to create audio with customizable fade-out
def create_audio_with_fade_out(half_life):
    sample_rate = 44100
    frequency = 440  # A4 note (440 Hz)
    duration = 2  # seconds
    t = np.linspace(0, duration, int(sample_rate * duration), endpoint=False)
    
    # Exponential decay based on user-selected half-life
    fade_out_factor = np.exp(-np.log(2) * t / half_life)
    
    audio_data = 0.5 * np.sin(2 * np.pi * frequency * t) * fade_out_factor

    # File naming based on half-life
    half_life_str = f"{half_life:.3f}".replace(".", "_")  # Format filename
    wav_path = f"generated_{half_life_str}s.wav"

    # Save as WAV
    with wave.open(wav_path, 'wb') as wf:
        wf.setnchannels(1)  # Mono
        wf.setsampwidth(2)  # 16-bit PCM
        wf.setframerate(sample_rate)
        wf.writeframes((audio_data * 32767).astype(np.int16))

    return wav_path

# Convert WAV to MP3
def convert_to_mp3(half_life):
    wav_path = create_audio_with_fade_out(half_life)
    mp3_path = wav_path.replace(".wav", ".mp3")

    audio = AudioSegment.from_wav(wav_path)
    audio.export(mp3_path, format="mp3")

    return mp3_path

# Play last generated MP3
def play_last_audio(half_life):
    half_life_str = f"{half_life:.3f}".replace(".", "_")
    mp3_path = f"generated_{half_life_str}s.mp3"
    
    if os.path.exists(mp3_path):
        return mp3_path
    else:
        return None  # No file found

# Gradio UI
with gr.Blocks() as app:
    gr.Markdown("""
    # 🎵 Sound Generator with Custom Fade-out  
    **Created on:** February 14, 2025  
    **Made by:** ESP  
    **Description:**  
    This app generates a **sine wave sound** that fades out based on a user-defined **half-life**.  
    - Adjust the **half-life** with the slider (1s to 0.001s).  
    - Click **"Generate MP3"** to create a new sound.  
    - Click **"Play Last MP3"** to listen to the last generated sound.  
    - The file name includes the **half-life value** (e.g., `generated_0_5s.mp3`).  
    """)

    # Slider for Half-Life Selection
    half_life_slider = gr.Slider(minimum=0.001, maximum=1, value=0.5, label="Half-Life (seconds)", step=0.001)

    generate_button = gr.Button("Generate MP3")
    play_button = gr.Button("Play Last MP3")

    audio_output = gr.File()
    audio_player = gr.Audio()

    generate_button.click(convert_to_mp3, inputs=[half_life_slider], outputs=audio_output)
    play_button.click(play_last_audio, inputs=[half_life_slider], outputs=audio_player)

app.launch()