import gradio as gr
import sys
import os
import importlib.util
from pathlib import Path
from huggingface_hub import hf_hub_download

print("===== Application Startup =====")

MODEL_REPO = "fcu52005505/X281-weights"
MODEL_FILE = "core_logic.so"
CACHE_DIR = Path("./model_cache")
CACHE_DIR.mkdir(exist_ok=True)

core_logic = None

# 檢查 HF Token
HF_TOKEN = os.getenv("HF_TOKEN")
if HF_TOKEN is None:
    raise RuntimeError(
        "❌ 缺少 HF_TOKEN！請在 Space 的 Settings → Variables and secrets 設定。"
    )

print(f"HF_TOKEN loaded: {HF_TOKEN is not None}")

# 下載 .so（使用快取）
so_path = CACHE_DIR / MODEL_FILE

if not so_path.exists():
    print(f"📥 正在從 {MODEL_REPO} 下載 {MODEL_FILE} ...")
    downloaded_path = hf_hub_download(
        repo_id=MODEL_REPO,
        filename=MODEL_FILE,
        repo_type="model",
        token=HF_TOKEN,
        local_dir=str(CACHE_DIR),
        local_dir_use_symlinks=False
    )
    print(f"✅ .so 下載完成: {downloaded_path}")
else:
    print(f"✅ 使用快取 .so: {so_path}")

# 動態載入 core_logic.so
try:
    spec = importlib.util.spec_from_file_location(
        "core_logic",
        str(so_path)
    )
    if spec and spec.loader:
        core_logic = importlib.util.module_from_spec(spec)
        sys.modules["core_logic"] = core_logic
        spec.loader.exec_module(core_logic)
        print("✅ core_logic.so 載入成功")
    else:
        raise RuntimeError("❌ 無法建立模組規格 (Spec creation failed)")
except Exception as e:
    print(f"❌ core_logic.so 載入發生錯誤: {e}")
    import traceback
    traceback.print_exc()
    core_logic = None

# ==========================================
def bridge_function(file_obj, zoom_level, preserve_details, progress=gr.Progress()):
    if core_logic is None:
        yield "❌ 嚴重錯誤：核心模組載入失敗 (No module named 'core_logic')，請檢查 Logs。", None
        return

    if file_obj is None:
        yield "❌ 請先上傳檔案", None
        return

    def update_progress(p, msg):
        progress(p, desc=msg)

    yield "🚀 檔案接收成功，處理中...", None

    try:
        result_msg, output_path = core_logic.run_conversion(
            file_obj.name,
            zoom_level,
            preserve_details,
            progress_callback=update_progress
        )

        if "Success" in result_msg:
            yield f"✅ 轉換成功！ ({result_msg})", output_path
        else:
            yield f"❌ {result_msg}", None

    except Exception as e:
        yield f"❌ 執行錯誤: {e}", None


# ==========================================

with gr.Blocks(title="GeoJSON 轉 PMTiles") as demo:
    gr.Markdown("## 🗺️ GeoJSON to PMTiles")

    with gr.Row():
        with gr.Column():
            input_file = gr.File(label="上傳 GeoJSON (自動開始)")
            with gr.Group():
                zoom_slider = gr.Slider(0, 20, value=14, step=1, label="Max Zoom")
                preserve_checkbox = gr.Checkbox(label="強制保留細節", value=True)
            btn = gr.Button("開始轉換")

        with gr.Column():
            status_box = gr.Textbox(label="狀態", value="等待中...", interactive=False)
            output_file = gr.File(label="下載")

    input_file.upload(
        bridge_function,
        [input_file, zoom_slider, preserve_checkbox],
        [status_box, output_file]
    )
    btn.click(
        bridge_function,
        [input_file, zoom_slider, preserve_checkbox],
        [status_box, output_file]
    )


# ==========================================
if __name__ == "__main__":
    demo.queue(default_concurrency_limit=10).launch(show_api=False)