"""
Unified service with FastAPI (for MonitaQC) and Gradio (for testing/demo).
This allows multiple MonitaQC vision engines to use the API while keeping the Gradio UI accessible.
"""

from fastapi import FastAPI, File, UploadFile, Form, HTTPException
from fastapi.responses import JSONResponse
import gradio as gr
import onnxruntime as ort
import numpy as np
import cv2
from huggingface_hub import hf_hub_download
import os
from io import BytesIO
from typing import Optional
import logging

# Configure logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

# FastAPI app
app = FastAPI(
    title="Industrial Defect Detection API",
    description="ONNX-based defect detection service for MonitaQC vision engines",
    version="1.0.0"
)

# Available models
MODELS = {
    "dental-implant": {"name": "Dental Implant", "repo": "smartfalcon-ai/Dental-Implant-Defect-Detection"},
    "data-matrix": {"name": "Data Matrix", "repo": "smartfalcon-ai/Data-Matrix-Defect-Detection"},
    "ball-pen": {"name": "Ball Pen", "repo": "smartfalcon-ai/Ball-Pen-Defect-Detection"},
    "knit-up": {"name": "Knit Up", "repo": "smartfalcon-ai/Knit-Up-Defect-Detection"},
    "knit-back": {"name": "Knit Back", "repo": "smartfalcon-ai/Knit-Back-Defect-Detection"},
    "jean-back": {"name": "Jean Back", "repo": "smartfalcon-ai/Jean-Back-Defect-Detection"},
    "jean-up": {"name": "Jean Up", "repo": "smartfalcon-ai/Jean-Up-Defect-Detection"},
    "tire-cord": {"name": "Tire Cord", "repo": "smartfalcon-ai/Tire-Cord-Defect-Detection"}
}

# Example images for Gradio
EXAMPLES = [
    # Dental Implant
    ["examples/dental-implant-1.jpg", "Dental Implant", 0.25],
    ["examples/dental-implant-2.jpg", "Dental Implant", 0.25],
    ["examples/dental-implant-3.jpg", "Dental Implant", 0.25],
    # Data Matrix
    ["examples/data-matrix-1.jpg", "Data Matrix", 0.25],
    ["examples/data-matrix-2.jpg", "Data Matrix", 0.25],
    ["examples/data-matrix-3.jpg", "Data Matrix", 0.25],
    # Ball Pen
    ["examples/ball-pen-1.jpg", "Ball Pen", 0.25],
    ["examples/ball-pen-2.jpg", "Ball Pen", 0.25],
    ["examples/ball-pen-3.jpg", "Ball Pen", 0.25],
    # Knit Up
    ["examples/knit-up-1.jpg", "Knit Up", 0.25],
    ["examples/knit-up-2.jpg", "Knit Up", 0.25],
    ["examples/knit-up-3.jpg", "Knit Up", 0.25],
    # Knit Back
    ["examples/knit-back-1.jpg", "Knit Back", 0.25],
    ["examples/knit-back-2.jpg", "Knit Back", 0.25],
    ["examples/knit-back-3.jpg", "Knit Back", 0.25],
    # Jean Back
    ["examples/jean-back-1.jpg", "Jean Back", 0.25],
    ["examples/jean-back-2.jpg", "Jean Back", 0.25],
    ["examples/jean-back-3.jpg", "Jean Back", 0.25],
    # Jean Up
    ["examples/jean-up-1.jpg", "Jean Up", 0.25],
    ["examples/jean-up-2.jpg", "Jean Up", 0.25],
    ["examples/jean-up-3.jpg", "Jean Up", 0.25],
    # Tire Cord
    ["examples/tire-cord-1.jpg", "Tire Cord", 0.25],
    ["examples/tire-cord-2.jpg", "Tire Cord", 0.25],
    ["examples/tire-cord-3.jpg", "Tire Cord", 0.25],
]

# Model sessions cache
sessions = {}

# Default model
DEFAULT_MODEL = os.environ.get("DEFAULT_MODEL", "data-matrix")

# Inference parameters
IMG_SIZE = 640
IOU_THRESHOLD = 0.45


def get_session(model_key: str):
    """Get or create ONNX inference session for a model."""
    if model_key not in sessions:
        if model_key not in MODELS:
            raise ValueError(f"Model '{model_key}' not found. Available: {list(MODELS.keys())}")

        try:
            hf_token = os.environ.get("HUGGINGFACE_TOKEN", None)
            repo_id = MODELS[model_key]["repo"]
            logger.info(f"Downloading model: {repo_id}")
            model_path = hf_hub_download(
                repo_id=repo_id,
                filename="best.onnx",
                token=hf_token
            )
            sessions[model_key] = ort.InferenceSession(
                model_path,
                providers=["CPUExecutionProvider"]
            )
            logger.info(f"Model '{model_key}' loaded successfully")
        except Exception as e:
            logger.error(f"Failed to load model '{model_key}': {e}")
            raise

    return sessions[model_key]


def preprocess(img):
    """Preprocess image for ONNX model."""
    h, w = img.shape[:2]
    img_resized = cv2.resize(img, (IMG_SIZE, IMG_SIZE))
    img_resized = img_resized.astype(np.float32) / 255.0
    img_resized = img_resized.transpose(2, 0, 1)
    img_resized = np.expand_dims(img_resized, 0)
    return img_resized, w, h


def xywh2xyxy(x):
    """Convert box format from xywh to xyxy."""
    y = np.copy(x)
    y[:, 0] = x[:, 0] - x[:, 2] / 2
    y[:, 1] = x[:, 1] - x[:, 3] / 2
    y[:, 2] = x[:, 0] + x[:, 2] / 2
    y[:, 3] = x[:, 1] + x[:, 3] / 2
    return y


def non_max_suppression(preds, conf_thres=0.25, iou_thres=0.45):
    """Apply NMS to predictions."""
    preds = preds[0]
    preds = preds[preds[:, 4] > conf_thres]
    if preds.shape[0] == 0:
        return []

    boxes = xywh2xyxy(preds[:, :4])
    scores = preds[:, 4]
    class_scores = preds[:, 5:]
    cls_ids = np.argmax(class_scores, axis=1)
    cls_conf = class_scores.max(axis=1)
    final_scores = scores * cls_conf

    indices = cv2.dnn.NMSBoxes(
        bboxes=boxes.tolist(),
        scores=final_scores.tolist(),
        score_threshold=conf_thres,
        nms_threshold=iou_thres
    )

    if len(indices) == 0:
        return []

    indices = indices.flatten()
    output = []
    for idx in indices:
        x1, y1, x2, y2 = boxes[idx]
        output.append({
            "bbox": [float(x1), float(y1), float(x2), float(y2)],
            "confidence": float(final_scores[idx]),
            "class_id": int(cls_ids[idx]),
            "x1": float(x1),
            "y1": float(y1),
            "x2": float(x2),
            "y2": float(y2)
        })
    return output


# ============================================================================
# FastAPI Endpoints (for MonitaQC vision engines)
# ============================================================================

@app.get("/")
async def root():
    """API root endpoint."""
    return {
        "service": "Industrial Defect Detection API",
        "version": "1.0.0",
        "endpoints": {
            "api": "/docs",
            "gradio": "/gradio"
        },
        "models": list(MODELS.keys()),
        "default_model": DEFAULT_MODEL
    }


@app.get("/health")
async def health_check():
    """Health check endpoint."""
    return {"status": "healthy", "models_loaded": len(sessions)}


@app.get("/models")
async def list_models():
    """List all available models."""
    return {
        "models": {k: v["name"] for k, v in MODELS.items()},
        "loaded": list(sessions.keys())
    }


@app.post("/v1/object-detection/detect")
async def detect_defects(
    image: UploadFile = File(...),
    model: Optional[str] = Form(DEFAULT_MODEL),
    confidence: Optional[float] = Form(0.25)
):
    """
    Detect defects in an uploaded image.

    Compatible with MonitaQC's YOLO inference API format.

    Args:
        image: Image file to analyze
        model: Model name to use (default: data-matrix)
        confidence: Confidence threshold (default: 0.25)

    Returns:
        JSON array of detections with bbox, confidence, and class_id
    """
    try:
        # Read image from upload
        contents = await image.read()
        nparr = np.frombuffer(contents, np.uint8)
        img_bgr = cv2.imdecode(nparr, cv2.IMREAD_COLOR)

        if img_bgr is None:
            raise HTTPException(status_code=400, detail="Invalid image file")

        # Get model session
        session = get_session(model)

        # Preprocess
        blob, orig_w, orig_h = preprocess(img_bgr)

        # Run inference
        preds = session.run(None, {"images": blob})[0]

        # Post-process
        detections = non_max_suppression(preds, confidence, IOU_THRESHOLD)

        # Scale bboxes back to original image size
        for det in detections:
            det["bbox"][0] = det["bbox"][0] / IMG_SIZE * orig_w
            det["bbox"][1] = det["bbox"][1] / IMG_SIZE * orig_h
            det["bbox"][2] = det["bbox"][2] / IMG_SIZE * orig_w
            det["bbox"][3] = det["bbox"][3] / IMG_SIZE * orig_h
            det["x1"] = det["bbox"][0]
            det["y1"] = det["bbox"][1]
            det["x2"] = det["bbox"][2]
            det["y2"] = det["bbox"][3]

        logger.info(f"Processed image with model '{model}': {len(detections)} detections")

        return detections

    except Exception as e:
        logger.error(f"Detection error: {e}")
        raise HTTPException(status_code=500, detail=str(e))


@app.post("/v1/object-detection/{model_name}/detect")
async def detect_defects_with_model(
    model_name: str,
    image: UploadFile = File(...),
    confidence: Optional[float] = Form(0.25)
):
    """
    Detect defects using a specific model (path parameter).

    This endpoint is compatible with MonitaQC's current YOLO API format.

    Args:
        model_name: Model to use (e.g., 'data-matrix', 'dental-implant')
        image: Image file to analyze
        confidence: Confidence threshold (default: 0.25)

    Returns:
        JSON array of detections
    """
    return await detect_defects(image, model_name, confidence)


# ============================================================================
# Gradio Interface (for testing/demo)
# ============================================================================

def gradio_inference(image, model_display_name, conf_threshold):
    """Inference function for Gradio UI."""
    # Find model key from display name
    model_key = None
    for key, val in MODELS.items():
        if val["name"] == model_display_name:
            model_key = key
            break

    if model_key is None:
        return image

    session = get_session(model_key)
    img_bgr = cv2.cvtColor(image, cv2.COLOR_RGB2BGR)
    blob, orig_w, orig_h = preprocess(img_bgr)
    preds = session.run(None, {"images": blob})[0]
    detections = non_max_suppression(preds, conf_threshold, IOU_THRESHOLD)

    for det in detections:
        x1 = int(det["x1"] / IMG_SIZE * orig_w)
        y1 = int(det["y1"] / IMG_SIZE * orig_h)
        x2 = int(det["x2"] / IMG_SIZE * orig_w)
        y2 = int(det["y2"] / IMG_SIZE * orig_h)
        score = det["confidence"]
        cls_id = det["class_id"]

        label = f"{cls_id}:{score:.2f}"
        cv2.rectangle(img_bgr, (x1, y1), (x2, y2), (0, 255, 0), 2)
        cv2.putText(img_bgr, label, (x1, y1 - 5), cv2.FONT_HERSHEY_SIMPLEX, 0.6, (0, 255, 0), 2)

    return cv2.cvtColor(img_bgr, cv2.COLOR_BGR2RGB)


# Create Gradio interface
gradio_app = gr.Interface(
    fn=gradio_inference,
    inputs=[
        gr.Image(type="numpy"),
        gr.Dropdown([v["name"] for v in MODELS.values()], label="Select Model"),
        gr.Slider(minimum=0.0, maximum=1.0, value=0.25, step=0.01, label="Confidence Threshold")
    ],
    outputs=gr.Image(type="numpy"),
    title="Industrial Defect Detection - Testing Interface",
    description="""
    **Testing Interface** for Industrial Defect Detection models.

    - **For Production Use:** Use the FastAPI endpoints at `/v1/object-detection/detect`
    - **For Testing:** Use this Gradio interface to visually inspect results

    Upload an image, select a defect model, and adjust the confidence threshold.
    You can also choose from the samples at the bottom of the page.
    """,
    examples=EXAMPLES,
    examples_per_page=24,
)

# Mount Gradio app to FastAPI
app = gr.mount_gradio_app(app, gradio_app, path="/gradio")


if __name__ == "__main__":
    import uvicorn
    port = int(os.environ.get("PORT", 8000))
    host = os.environ.get("HOST", "0.0.0.0")

    logger.info(f"Starting Industrial Defect Detection Service on {host}:{port}")
    logger.info(f"  - FastAPI docs: http://{host}:{port}/docs")
    logger.info(f"  - Gradio UI: http://{host}:{port}/gradio")
    logger.info(f"Available models: {list(MODELS.keys())}")
    logger.info(f"Default model: {DEFAULT_MODEL}")

    uvicorn.run(app, host=host, port=port)