from typing import Dict, List, Any
from torchvision.models import resnet18, ResNet18_Weights
from torchvision.io import read_image
from PIL import Image
import io
import requests
import torchvision.transforms.functional as transform

class EndpointHandler():
    def __init__(self, path=""):
        weights = ResNet18_Weights.DEFAULT
        self.pipeline = resnet18(weights=weights)
        self.preprocess = weights.transforms()
        self.pipeline.eval()

    def __call__(self, data: Dict[str, Any]) -> List[Dict[str, Any]]:
        """
       data args:
            inputs (:obj: `str`)
      Return:
            A :obj:`list` | `dict`: will be serialized and returned
        """
        # get inputs
        inputs = data.pop("inputs",data)
        if inputs.startswith("http") or inputs.startswith("www"):
            response = requests.get(inputs).content
            img = transform.to_tensor(Image.open(io.BytesIO(response)))
        else:
            img = read_image(inputs)

        batch = self.preprocess(img).unsqueeze(0)
        prediction = self.pipeline(batch).squeeze(0).softmax(0)
        
        return prediction.tolist()