import os
import subprocess
from fastapi import FastAPI, File, UploadFile, HTTPException
from fastapi.responses import JSONResponse
from fastapi.staticfiles import StaticFiles
import uvicorn

# Define directories for uploads and outputs
UPLOAD_FOLDER = 'uploads_gradio'
OUTPUT_FOLDER = 'outputs_gradio'

# Create directories if they don't exist
os.makedirs(UPLOAD_FOLDER, exist_ok=True)
os.makedirs(OUTPUT_FOLDER, exist_ok=True)

def animate_image(file_path):
    """
    Function to process the uploaded image and generate an animated GIF.
    
    Args:
        file_path (str): Path to the uploaded file.
    
    Returns:
        str: Path to the generated GIF.
    """
    if not file_path:
        raise ValueError("No file uploaded.")

    input_path = file_path
    filename = os.path.basename(input_path)
    base, ext = os.path.splitext(filename)
    
    # Define the annotation directory for this specific image
    char_anno_dir = os.path.join(OUTPUT_FOLDER, f"{base}_out")
    os.makedirs(char_anno_dir, exist_ok=True)
    
    try:
        # Validate file extension
        allowed_extensions = ['.png', '.jpg', '.jpeg', '.bmp']
        if ext.lower() not in allowed_extensions:
            raise ValueError("Unsupported file type. Please upload an image file (png, jpg, jpeg, bmp).")
        
        # Run the image_to_animation.py script with required arguments
        subprocess.run([
            'python', 'examples/image_to_animation.py',
            input_path, char_anno_dir
        ], check=True)
        
        # Path to the generated GIF
        gif_path = os.path.join(char_anno_dir, "video.gif")
        
        if os.path.exists(gif_path):
            return gif_path
        else:
            raise FileNotFoundError("Animation failed to generate. Please ensure the input image contains clear humanoid drawings.")
    
    except subprocess.CalledProcessError as e:
        raise RuntimeError(f"Error during processing: {e}")
    except Exception as e:
        raise RuntimeError(f"Unexpected error: {e}")

app = FastAPI()

# Serve the outputs folder as static files so that generated GIFs can be accessed directly
app.mount("/outputs", StaticFiles(directory=OUTPUT_FOLDER), name="outputs")

@app.post("/animate")
async def animate_endpoint(file: UploadFile = File(...)):
    try:
        # Save the uploaded file
        file_path = os.path.join(UPLOAD_FOLDER, file.filename)
        with open(file_path, "wb") as f:
            f.write(await file.read())
        
        gif_path = animate_image(file_path)
        
        # Construct a URL to access the generated GIF
        gif_url = f"/outputs/{os.path.basename(os.path.dirname(gif_path))}/{os.path.basename(gif_path)}"
        
        return JSONResponse({"gif_url": gif_url})
    except ValueError as ve:
        raise HTTPException(status_code=400, detail=str(ve))
    except FileNotFoundError as fnfe:
        raise HTTPException(status_code=404, detail=str(fnfe))
    except RuntimeError as re:
        raise HTTPException(status_code=500, detail=str(re))
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Unexpected error: {e}")


if __name__ == "__main__":
    # Use the PORT environment variable provided by Hugging Face Spaces
    port = int(os.getenv("PORT", "7860"))
    uvicorn.run(app, host="0.0.0.0", port=port)