# handler.py

import os
import io
import tempfile
import numpy as np
from PIL import Image
from DepthFlow import DepthScene
from DepthFlow.Motion import Presets

class EndpointHandler():
    def __init__(self, path=""):
        """
        Initialize the handler and load necessary resources.
        This method is called once when the service starts.
        """
        # Initialize DepthFlow once for efficiency
        self.depthflow = DepthScene(backend='headless')

    def preprocess(self, inputs):
        """
        Preprocess the input data.
        
        Args:
            inputs (dict): The input payload containing the image data.
        
        Returns:
            str: Path to the preprocessed image file.
        """
        if 'image' not in inputs:
            raise ValueError("Missing 'image' in inputs")
        
        image_bytes = inputs['image'].read()
        image = Image.open(io.BytesIO(image_bytes)).convert('RGB')
        
        # Save image to a temporary file
        temp_image_file = tempfile.NamedTemporaryFile(suffix='.jpg', delete=False)
        image.save(temp_image_file.name)
        
        return temp_image_file.name

    def inference(self, image_path):
        """
        Perform the main inference logic.
        
        Args:
            image_path (str): Path to the preprocessed image file.
        
        Returns:
            str: Path to the output video file.
        """
        # Load the image into DepthFlow
        self.depthflow.input(image=image_path)
        
        # Set custom parameters (modify as needed)
        self.depthflow.state.height = 1
        self.depthflow.state.zoom = 1.1
        self.depthflow.state.dolly = 1
        self.depthflow.state.dof_enable = True
        self.depthflow.state.dof_intensity = 1.2
        self.depthflow.state.vignette_intensity = 40
        
        # Apply the animation preset
        self.depthflow.add_animation(Presets.Dolly())
        
        # Generate the output video
        temp_video_file = tempfile.NamedTemporaryFile(suffix='.mp4', delete=False)
        self.depthflow.update()
        self.depthflow.main(output=temp_video_file.name)
        
        return temp_video_file.name

    def postprocess(self, video_path):
        """
        Postprocess the output and prepare the response.
        
        Args:
            video_path (str): Path to the generated video file.
        
        Returns:
            dict: Response containing the video file.
        """
        with open(video_path, 'rb') as f:
            video_bytes = f.read()
        
        # Clean up temporary files
        os.remove(video_path)
        
        return {
            'video': video_bytes
        }

    def __call__(self, data):
        """
        Handle the incoming request.
        
        Args:
            inputs (dict): The input payload.
        
        Returns:
            dict: The response payload.
        """
        try:
            # Preprocess
            image_path = self.preprocess(data)
            
            # Inference
            video_path = self.inference(image_path)
            
            # Postprocess
            result = self.postprocess(video_path)
            
            # Clean up image file
            os.remove(image_path)
            
            return result
        except Exception as e:
            return {'error': str(e)}