ui_preview.py

#!/usr/bin/env python3
"""
Minimal UI preview launcher for app.py.

Purpose:
- Avoids heavy startup work (clones, downloads) by stubbing modules.
- Replaces training function with a no-op so you can safely click around.

Usage:
  python ui_preview.py

Requires:
  pip install gradio
"""

import sys
import types


# Stub out `spaces` so the @spaces.GPU decorator is a no-op
spaces_stub = types.ModuleType("spaces")

def _gpu_decorator(fn=None, *args, **kwargs):
    # Supports both @spaces.GPU and @spaces.GPU(...)
    if callable(fn):
        return fn

    def _wrap(f):
        return f

    return _wrap

spaces_stub.GPU = _gpu_decorator
sys.modules["spaces"] = spaces_stub


# Stub out download_qwen_image_models to avoid importing huggingface_hub
models_stub = types.ModuleType("download_qwen_image_models")
models_stub.DEFAULT_MODELS_DIR = "./_models_stub"

def _download_all_models(models_dir: str = models_stub.DEFAULT_MODELS_DIR):
    # Return a minimal shape that callers might expect; no downloads.
    return {"root": models_dir}

models_stub.download_all_models = _download_all_models
sys.modules["download_qwen_image_models"] = models_stub


# Import the real app after stubbing
import gradio as gr  # ensure gradio is installed
import importlib

app = importlib.import_module("app")


# Replace heavy training routine with a preview-friendly stub
def _preview_run_training(*args, **kwargs):
    # Generator to match Gradio streaming handler expectations
    msg = (
        "[UI PREVIEW]\n"
        "This is a UI-only preview. Training is disabled here.\n"
        "Click handlers are stubbed; no jobs will run.\n"
    )
    yield (msg, [], None)


app.run_training = _preview_run_training  # type: ignore[attr-defined]


def main():
    ui: gr.Blocks = app.build_ui()
    # For preview, simple launch without queue or allowed_paths
    ui.launch()


if __name__ == "__main__":
    main()