app.py

import gradio as gr
import ast
import astor
import os
from io import StringIO

# Mapping of Gradio components to Toga equivalents
GRADIO_TO_TOGA = {
    "Textbox": ("toga.TextInput", "style=Pack(padding=5)", "Text Input"),
    "Image": ("toga.Label", "Placeholder: Image file picker", "Image Upload"),
    "Button": ("toga.Button", "on_press=button_handler", "Submit"),
    "Markdown": ("toga.Label", "style=Pack(padding=5, font_size=14)", "Markdown Text"),
    "Audio": ("toga.Label", "Placeholder: Audio file picker", "Audio Upload"),
    "Video": ("toga.Label", "Placeholder: Video file picker", "Video Upload"),
}

# Parse Gradio app code
def parse_gradio_code(code):
    try:
        tree = ast.parse(code)
        components = []
        functions = []
        imports = []
        
        for node in ast.walk(tree):
            # Extract function definitions
            if isinstance(node, ast.FunctionDef):
                functions.append(node)
            # Extract Gradio component calls
            if isinstance(node, ast.Call) and hasattr(node.func, 'attr'):
                if node.func.attr in GRADIO_TO_TOGA:
                    component = node.func.attr
                    args = [ast.dump(arg, annotate_fields=False) for arg in node.args]
                    kwargs = {kw.arg: ast.dump(kw.value, annotate_fields=False) for kw in node.keywords}
                    components.append({"type": component, "args": args, "kwargs": kwargs})
            # Extract imports
            if isinstance(node, (ast.Import, ast.ImportFrom)):
                imports.append(node)
        
        return components, functions, imports
    except Exception as e:
        return [], [], [f"Error parsing code: {str(e)}"]

# Generate Toga code
def generate_toga_code(components, functions, imports):
    toga_code = [
        "import toga",
        "from toga.style import Pack",
        "from toga.style.pack import COLUMN",
        ""
    ]
    
    # Add imports
    toga_code.append("# Dependencies from Gradio app")
    for imp in imports:
        toga_code.append(astor.to_source(imp).strip())
    toga_code.append("")
    
    # Add function definitions
    toga_code.append("# Functions from Gradio app")
    for func in functions:
        toga_code.append(astor.to_source(func).strip())
    toga_code.append("")
    
    # Generate UI
    toga_code.extend([
        "def build(app):",
        "    box = toga.Box(style=Pack(direction=COLUMN, padding=10))",
        ""
    ])
    
    for idx, comp in enumerate(components):
        toga_comp, extra, label_prefix = GRADIO_TO_TOGA.get(comp["type"], ("toga.Label", f"Placeholder: {comp['type']} not supported", "Unknown"))
        
        if comp["type"] == "Textbox":
            label = comp["kwargs"].get("label", f"'{label_prefix} {idx}'")
            toga_code.append(f"    label_{idx} = toga.Label({label}, style=Pack(padding=(5, 5, 0, 5)))")
            toga_code.append(f"    input_{idx} = {toga_comp}({extra})")
            toga_code.append(f"    box.add(label_{idx})")
            toga_code.append(f"    box.add(input_{idx})")
        
        elif comp["type"] in ["Image", "Audio", "Video"]:
            file_types = {
                "Image": "['png', 'jpg', 'jpeg']",
                "Audio": "['mp3', 'wav']",
                "Video": "['mp4', 'avi']"
            }.get(comp["type"], "['*']")
            toga_code.append(f"    {comp['type'].lower()}_label_{idx} = toga.Label('{label_prefix}: None selected', style=Pack(padding=5))")
            toga_code.append(f"    def select_{comp['type'].lower()}_{idx}(widget):")
            toga_code.append(f"        path = app.main_window.open_file_dialog('Select {comp['type']}', file_types={file_types})")
            toga_code.append(f"        if path:")
            toga_code.append(f"            {comp['type'].lower()}_label_{idx}.text = f'{label_prefix}: {{path}}'")
            toga_code.append(f"    {comp['type'].lower()}_button_{idx} = toga.Button('Upload {comp['type']}', on_press=select_{comp['type'].lower()}_{idx}, style=Pack(padding=5))")
            toga_code.append(f"    box.add(toga.Label('{label_prefix}', style=Pack(padding=(5, 5, 0, 5))))")
            toga_code.append(f"    box.add({comp['type'].lower()}_button_{idx})")
            toga_code.append(f"    box.add({comp['type'].lower()}_label_{idx})")
        
        elif comp["type"] == "Button":
            label = comp["kwargs"].get("value", f"'{label_prefix} {idx}'")
            # Check for associated function in click events
            click_fn = comp["kwargs"].get("fn", f"{functions[0].name if functions else 'function'}")
            toga_code.append(f"    def button_handler_{idx}(widget):")
            toga_code.append(f"        # Call {click_fn} with inputs")
            toga_code.append(f"        pass  # Implement logic using input values")
            toga_code.append(f"    button_{idx} = {toga_comp}(label={label}, {extra})")
            toga_code.append(f"    box.add(button_{idx})")
        
        elif comp["type"] == "Markdown":
            text = comp["args"][0] if comp["args"] else f"'{label_prefix} {idx}'"
            toga_code.append(f"    markdown_{idx} = {toga_comp}({text}, {extra})")
            toga_code.append(f"    box.add(markdown_{idx})")
        
        else:
            toga_code.append(f"    placeholder_{idx} = {toga_comp}('{extra}', style=Pack(padding=5))")
            toga_code.append(f"    box.add(placeholder_{idx})")
    
    toga_code.extend([
        "",
        "    return box",
        "",
        "def main():",
        "    return toga.App('Gradio to Toga App', 'org.example.gradio2toga', startup=build)",
        "",
        "if __name__ == '__main__':",
        "    main().main_loop()"
    ])
    
    return "\n".join(toga_code)

# Conversion function
def convert_gradio_to_toga(file, code_text):
    if not file and not code_text:
        return None, None, "Please upload a Gradio app Python file or paste code in the textbox."
    
    try:
        # Use file if provided, else use text
        code = file.decode('utf-8') if file else code_text
        components, functions, imports = parse_gradio_code(code)
        
        if not components and functions and isinstance(functions[0], str):
            return None, None, f"Error: {functions[0]}"
        
        toga_code = generate_toga_code(components, functions, imports)
        output_path = "/tmp/toga_app.py"
        with open(output_path, "w") as f:
            f.write(toga_code)
        
        return output_path, toga_code, "Conversion successful! Preview the Toga code below and download the app."
    except Exception as e:
        return None, None, f"Error: {str(e)}"

# Gradio interface
with gr.Blocks(theme=gr.themes.Soft()) as interface:
    gr.Markdown("# Gradio to Toga Converter")
    gr.Markdown("Upload a Gradio app (.py) or paste the code below to convert to a Toga desktop app.")
    file_input = gr.File(label="Upload Gradio App", file_types=[".py"])
    code_input = gr.Textbox(label="Paste Gradio Code", lines=10, placeholder="Paste your Gradio Python code here...")
    convert_button = gr.Button("Convert to Toga")
    toga_preview = gr.Textbox(label="Toga Code Preview", lines=15, interactive=False)
    output = gr.File(label="Download Toga App")
    status = gr.Textbox(label="Status", interactive=False)
    
    convert_button.click(
        fn=convert_gradio_to_toga,
        inputs=[file_input, code_input],
        outputs=[output, toga_preview, status]
    )

# Run Gradio for Hugging Face Spaces
if __name__ == "__main__":
    interface.launch(server_name="0.0.0.0", server_port=int(os.environ.get("PORT", 7860)), quiet=True)