# app/main.py
from fastapi import FastAPI, UploadFile, File, Form
from fastapi.staticfiles import StaticFiles
from fastapi.responses import HTMLResponse, JSONResponse
from app.model import load_model, predict_from_bytes
from app.inference import load_classification_model, classify_bytes
from app.inference import load_classification_model, classify_bytes
from app.inference_yolo import classify_yolo_bytes, load_yolo_model
# from app.model import load_model, predict_pca_from_bytes
from ood_detector import OODDetector
from PIL import Image
import io  
import os
import uuid
from huggingface_hub import HfApi
import json, os
import hashlib



# ──────────────────────────────────────────────
# FastAPI setup
# ──────────────────────────────────────────────
app = FastAPI(title="NEMO Tools")

# app.add_middleware(
#     CORSMiddleware,
#     allow_origins=["*"],
#     allow_credentials=True,
#     allow_methods=["*"],
#     allow_headers=["*"],
# )

# ──────────────────────────────────────────────
# Static Frontend
# ──────────────────────────────────────────────
BASE_DIR = os.path.dirname(__file__)
STATIC_DIR = os.path.join(BASE_DIR, "static")
INDEX_HTML = os.path.join(STATIC_DIR, "index.html")

app.mount("/static", StaticFiles(directory=STATIC_DIR), name="static")


# --- CONFIGURATION ---
HF_TOKEN = os.environ.get("HF_TOKEN") 

DATASET_REPO_ID = "AndrewKof/NEMO-user-uploads"

api = HfApi(token=HF_TOKEN)

OOD_PATH = os.path.join(os.path.dirname(__file__), "OOD_Features")
# Check if artifacts exist before loading
if os.path.exists(OOD_PATH):
    ood_detector = OODDetector(
        model_path="Arew99/dinov2-costum", # Or your local MODEL_DIR
        feature_dir=OOD_PATH
    )
    print("✅ OOD Detector initialized.")
else:
    ood_detector = None
    print("⚠️ OOD artifacts not found. OOD detection will be skipped.")

def save_image_to_hub(image_bytes):
    """
    Uploads image only if it doesn't already exist in the dataset.
    Uses SHA256 hash of the content to detect duplicates.
    """
    # 1. Calculate the hash of the image content
    file_hash = hashlib.sha256(image_bytes).hexdigest()
    
    # 2. Use the hash as the filename (e.g., "user_images/a1b2c3d4....png")
    filename = f"user_images/{file_hash}.png"
    
    try:
        # 3. Check if this specific file already exists on the Hub
        if api.file_exists(repo_id=DATASET_REPO_ID, filename=filename, repo_type="dataset"):
            print(f"Skipping: {filename} already exists in dataset.")
            return  # <--- STOP HERE

        print(f"New image detected. Uploading {filename}...")
        
        # 4. Upload if it's new
        file_object = io.BytesIO(image_bytes)
        api.upload_file(
            path_or_fileobj=file_object,
            path_in_repo=filename,
            repo_id=DATASET_REPO_ID,
            repo_type="dataset"
        )
        print("Upload successful!")
        
    except Exception as e:
        print(f"Error checking/uploading image: {e}")

@app.get("/", response_class=HTMLResponse)
def serve_frontend():
    """Serve the web interface."""
    with open(INDEX_HTML, "r", encoding="utf-8") as f:
        return f.read()

# ──────────────────────────────────────────────
# Model Initialization
# ──────────────────────────────────────────────
print("🚀 Loading DINOv2 custom model...")
model_device_tuple = load_model()
print("✅ Model loaded and ready for inference!")

# warm-up on startup
load_classification_model()

# --- Load classification model & labels once at startup ---
MAP_PATH = os.path.join(os.path.dirname(__file__), "id2name.json")
with open(MAP_PATH, "r") as f:
    ID2NAME = json.load(f)

cls_model = load_model()
print("✅ Classification model loaded and ready for inference!")

# ──────────────────────────────────────────────
# API Endpoints
# ──────────────────────────────────────────────
@app.post("/attention")
async def generate_attention(file: UploadFile = File(...)):
    """Generate and return mean attention map for uploaded image."""
    image_bytes = await file.read()
    save_image_to_hub(image_bytes)
    result = predict_from_bytes(model_device_tuple, image_bytes)
    return result

# @app.post("/classify")
# async def classify(
#     file: UploadFile = File(...), 
#     model: str = Form("dino")  # <--- Read 'model' from FormData (default 'dino')
# ):
#     image_bytes = await file.read()
#     save_image_to_hub(image_bytes)
#     if model == "yolo":
#         print("🧠 Running YOLOv11 Inference...")
#         return classify_yolo_bytes(image_bytes)
#     else:
#         print("🦕 Running DINOv2 Inference...")
#         return classify_bytes(image_bytes)

@app.post("/classify")
async def classify(
    file: UploadFile = File(...), 
    model: str = Form("dino")
):
    image_bytes = await file.read()
    save_image_to_hub(image_bytes)
    
    # 1. First, check if it is OOD (only if detector is loaded)
    ood_info = None
    if ood_detector:
        pil_img = Image.open(io.BytesIO(image_bytes)).convert("RGB")
        ood_info = ood_detector.predict(pil_img)
    
    # 2. Run standard classification
    if model == "yolo":
        response = classify_yolo_bytes(image_bytes)
    else:
        response = classify_bytes(image_bytes)
    
    # 3. Attach OOD info to the response
    if ood_info:
        response["ood_metadata"] = ood_info
        
    return response

@app.get("/api")
def api_root():
    return {"message": "NEMO Tools backend running."}

# ──────────────────────────────────────────────
if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=7860)