import os
import sys
sys.path.insert(0, os.path.dirname(__file__))

from collections import defaultdict
import folder_paths
from models.baseline import BiRefNet
from config import Config

import cv2
import numpy as np
from PIL import Image

import torch
import torch.nn as nn
from torchvision import transforms

from loguru import logger
from folder_paths import models_dir
from BiRefNetutils import check_download_model

config = Config()

class BiRefNet_img_processor:
    def __init__(self, config):
        self.config = config
        self.data_size = (config.size, config.size)
        self.transform_image = transforms.Compose([
            transforms.Resize(self.data_size),
            transforms.ToTensor(),
            transforms.Normalize([0.485, 0.456, 0.406], [0.229, 0.224, 0.225]),
        ])

    def __call__(self, _image: np.array):
        _image_rs = cv2.resize(_image, (self.config.size, self.config.size), interpolation=cv2.INTER_LINEAR)
        _image_rs = Image.fromarray(np.uint8(_image_rs*255)).convert('RGB')
        image = self.transform_image(_image_rs)
        return image

class BiRefNet_node:
    def __init__(self):
        self.ready = False

    def load(self, weight_path, device, verbose=False):
        try:
            map_location = 'cpu' if device == 'cpu' else None
            if device == 'mps' and torch.backends.mps.is_available():
                map_location = torch.device('mps')
                
            self.model = BiRefNet()
            state_dict = torch.load(weight_path, map_location=map_location)
            unwanted_prefix = '_orig_mod.'
            for k, v in list(state_dict.items()):
                if k.startswith(unwanted_prefix):
                    state_dict[k[len(unwanted_prefix):]] = state_dict.pop(k)
            
            self.model.load_state_dict(state_dict)
            self.model.to(device)
            self.model.eval()

            self.processor = BiRefNet_img_processor(config)
            self.ready = True
            if verbose:
                logger.debug("Model loaded successfully on device: {}".format(device))
        except Exception as e:
            logger.error(f"Failed to load the model: {e}")
            self.ready = False
            raise RuntimeError(f"Model loading failed: {e}")


    # Correctly move INPUT_TYPES to the class level
    @classmethod
    def INPUT_TYPES(cls):
        # Example structure, adjust according to your actual input requirements
        return {
            "required": {
                "image": ("IMAGE", {}),
                "device": (["auto", "cpu", "mps"] + [f"cuda:{i}" for i in range(torch.cuda.device_count())], {"default": "auto"}),
            },
            "optional": {
                # Define optional inputs if any
            }
        }

    RETURN_TYPES = ("MASK", )
    RETURN_NAMES = ("mask", )
    FUNCTION = "matting"
    CATEGORY = "Fooocus"

    def matting(self, image, device):
        # process auto device
        if device == "auto":
            if torch.backends.mps.is_available():
                device = "mps"
            elif torch.cuda.is_available():
                device = "cuda"
            else:
                device = "cpu"

        if not self.ready:
            weight_path = os.path.join(models_dir, "BiRefNet", "BiRefNet-ep480.pth")
            check_download_model(weight_path)
            self.load(weight_path, device=device)
        
        image = image.squeeze().numpy()
        img = self.processor(image)
        inputs = img[None, ...].to(device)
        logger.debug(f"{inputs.shape}")
        
        with torch.no_grad():
            self.model.to(device)  # Move the model to the selected device
            scaled_preds = self.model(inputs)[-1].sigmoid()

        res = nn.functional.interpolate(
            scaled_preds[0].unsqueeze(0),
            size=image.shape[:2],
            mode='bilinear',
            align_corners=True
        )
        return res


NODE_CLASS_MAPPINGS = {
    "BiRefNet": BiRefNet_node,
}

# A dictionary that contains the friendly/humanly readable titles for the nodes
NODE_DISPLAY_NAME_MAPPINGS = {
    "BiRefNet": "BiRefNet Segmentation",
}