import streamlit as st
import numpy as np
import cv2
from PIL import Image

# Set the page config
st.set_page_config(page_title="Emotion Recognition App", layout="centered")

st.title("Emotion Recognition App")

# Upload an image
uploaded_file = st.file_uploader("Upload an image", type=["jpg", "jpeg", "png"])

# Load OpenCV's pre-trained face detection model
face_cascade = cv2.CascadeClassifier(cv2.data.haarcascades + "haarcascade_frontalface_default.xml")

# Define a simple emotion detection function
def detect_emotion(face):
    """
    Mock function to assign a random emotion.
    Replace with an actual emotion detection model.
    """
    return "Happy"  # Replace with your logic

# Resize image to reduce memory usage
def resize_image(image, max_size=(800, 800)):
    """
    Resizes the image to the specified maximum size while maintaining aspect ratio.
    """
    image.thumbnail(max_size, Image.Resampling.LANCZOS)
    return image

# Process the uploaded image
if uploaded_file is not None:
    # Check file size to prevent loading large images
    if uploaded_file.size > 10 * 1024 * 1024:  # 10 MB limit
        st.error("File too large. Please upload an image smaller than 10 MB.")
    else:
        # Open and resize the image
        image = Image.open(uploaded_file)
        image = resize_image(image)

        # Convert image to numpy array
        image_np = np.array(image)

        # Convert image to grayscale for face detection
        gray_image = cv2.cvtColor(image_np, cv2.COLOR_RGB2GRAY)

        # Detect faces
        faces = face_cascade.detectMultiScale(gray_image, scaleFactor=1.1, minNeighbors=5, minSize=(30, 30))

        if len(faces) > 0:
            for (x, y, w, h) in faces:
                # Draw rectangle around the face
                cv2.rectangle(image_np, (x, y), (x+w, y+h), (0, 255, 0), 2)

                # Assign a dummy emotion
                emotion = detect_emotion(None)

                # Display emotion above the face
                cv2.putText(
                    image_np,
                    emotion,
                    (x, y - 10),
                    cv2.FONT_HERSHEY_SIMPLEX,
                    0.9,
                    (255, 0, 0),
                    2,
                )

            # Display the processed image
            st.image(image_np, caption="Processed Image", use_column_width=True)
        else:
            st.warning("No faces detected in the image.")