import gradio as gr
import subprocess
import os
import tempfile
import imageio_ffmpeg

def convert_audio(input_files, progress=gr.Progress()):
    if not input_files:
        return []

    # This dynamically gets the path to the FFmpeg binary that pip installed!
    ffmpeg_exe = imageio_ffmpeg.get_ffmpeg_exe()
    
    output_files = []
    # Create a temporary directory to store the converted files safely
    out_dir = tempfile.mkdtemp()

    # progress.tqdm creates a progress bar in the Gradio UI
    for file_path in progress.tqdm(input_files, desc="Converting Audio..."):
        filename = os.path.basename(file_path)
        name_only = os.path.splitext(filename)[0]
        
        out_path = os.path.join(out_dir, f"{name_only}_96k_24b.m4a")

        # FFmpeg command using the pip-installed binary
        command = [
            ffmpeg_exe, "-y", "-v", "error",
            "-i", file_path,
            "-c:a", "alac",        # Apple Lossless Audio Codec
            "-ar", "96000",        # Downsample to 96kHz
            "-sample_fmt", "s32p", # Padding to ensure 24-bit depth is preserved
            out_path
        ]

        try:
            # Execute the conversion
            subprocess.run(command, check=True)
            output_files.append(out_path)
        except subprocess.CalledProcessError as e:
            print(f"Error processing {filename}: {e}")
            
    return output_files

# Build the Gradio Interface
with gr.Blocks(title="High-Res Audio Converter") as app:
    gr.Markdown("# 🎵 Pure-Python High-Res FLAC to ALAC Converter")
    gr.Markdown("Upload **384kHz / 24-bit FLAC** files. They will be converted to **96kHz / 24-bit ALAC (.m4a)** natively in your Python environment.")
    
    with gr.Row():
        audio_in = gr.File(label="1. Upload FLAC files", file_count="multiple", file_types=[".flac"], type="filepath")
        audio_out = gr.File(label="2. Download Converted Files", file_count="multiple", interactive=False)
        
    convert_btn = gr.Button("Convert to ALAC (96kHz 24-bit)", variant="primary")
    
    convert_btn.click(fn=convert_audio, inputs=audio_in, outputs=audio_out)

if __name__ == "__main__":
    app.launch()