import base64
import io
from typing import Any, Dict, List

import requests
import torch
from PIL import Image
from transformers import TrOCRProcessor, VisionEncoderDecoderModel


device = "cuda" if torch.cuda.is_available() else "cpu"


class EndpointHandler:
    def __init__(self, path=""):
        self.processor = TrOCRProcessor.from_pretrained(path)
        self.model = VisionEncoderDecoderModel.from_pretrained(path)

        self.model.to(device)

    def __call__(self, data: Dict[str, Any]) -> List[Dict[str, Any]]:
        inputs = data.pop("inputs", data)
        image_input = inputs.get("image")

        if not image_input:
            return {"error": "No image provided."}

        try:
            if image_input.startswith("http"):
                response = requests.get(image_input, stream=True)
                if response.status_code == 200:
                    image = Image.open(response.raw).convert("RGB")
                else:
                    return {
                        "error": f"Failed to fetch image. Status code: {response.status_code}"
                    }
            else:
                image_data = base64.b64decode(image_input)
                image = Image.open(io.BytesIO(image_data)).convert("RGB")
        except Exception as e:
            return {"error": f"Failed to process the image. Details: {str(e)}"}

        pixel_values = self.processor(images=image, return_tensors="pt").pixel_values

        generated_ids = self.model.generate(pixel_values.to(device))

        prediction = self.processor.batch_decode(
            generated_ids, skip_special_tokens=True
        )
        return {"text": prediction[0]}