import gradio as gr
import torch
import torch.nn as nn
import torch.nn.functional as F
import clip
import pandas as pd
import hashlib
import numpy as np
import cv2
from PIL import Image

# if you changed the MLP architecture during training, change it also here:
class MLP(nn.Module):
    def __init__(self, input_size, xcol="emb", ycol="avg_rating"):
        super().__init__()
        self.input_size = input_size
        self.xcol = xcol
        self.ycol = ycol
        self.layers = nn.Sequential(
            nn.Linear(self.input_size, 1024),
            nn.Dropout(0.2),
            nn.Linear(1024, 128),
            nn.Dropout(0.2),
            nn.Linear(128, 64),
            nn.Dropout(0.1),
            nn.Linear(64, 16),
            nn.Linear(16, 1),
        )

    def forward(self, x):
        return self.layers(x)

def _binary_array_to_hex(arr):
    bit_string = ''.join(str(b) for b in 1 * arr.flatten())
    width = int(np.ceil(len(bit_string) / 4))
    return '{:0>{width}x}'.format(int(bit_string, 2), width=width)

def phashstr(image, hash_size=8, highfreq_factor=4):
    if hash_size < 2:
        raise ValueError('Hash size must be greater than or equal to 2')

    import scipy.fftpack
    img_size = hash_size * highfreq_factor
    image = image.convert('L').resize((img_size, img_size), Image.Resampling.LANCZOS)
    pixels = np.asarray(image)
    dct = scipy.fftpack.dct(scipy.fftpack.dct(pixels, axis=0), axis=1)
    dctlowfreq = dct[:hash_size, :hash_size]
    med = np.median(dctlowfreq)
    diff = dctlowfreq > med
    return _binary_array_to_hex(diff.flatten())

def normalized(a, axis=-1, order=2):
    l2 = np.atleast_1d(np.linalg.norm(a, order, axis))
    l2[l2 == 0] = 1
    return a / np.expand_dims(l2, axis)

def predict(image):
    model = MLP(768)  # CLIP embedding dim is 768 for CLIP ViT L 14
    pthpath = "https://huggingface.co/haor/aesthetics/resolve/main/sac%2Blogos%2Bava1-l14-linearMSE.pth"
    device = "cuda" if torch.cuda.is_available() else "cpu"

    model.load_state_dict(torch.hub.load_state_dict_from_url(pthpath, map_location=device))
    model.to(device).eval()
    model2, preprocess = clip.load("ViT-L/14", device=device)

    image = Image.fromarray(image)  
    image_np = cv2.cvtColor(np.array(image), cv2.COLOR_RGB2GRAY)
    laplacian_variance = cv2.Laplacian(image_np, cv2.CV_64F).var()
    phash = phashstr(image)
    md5 = hashlib.md5(image.tobytes()).hexdigest()
    sha1 = hashlib.sha1(image.tobytes()).hexdigest()

    inputs = preprocess(image).unsqueeze(0).to(device)

    with torch.no_grad():
        img_emb = model2.encode_image(inputs)
        img_emb = normalized(img_emb.cpu().numpy())
        prediction = model(torch.from_numpy(img_emb).to(device).type(torch.cuda.FloatTensor)).item()

    result = {
        "clip_aesthetic": prediction,
        "phash": phash,
        "md5": md5, 
        "sha1": sha1,
        "laplacian_variance": laplacian_variance
    }
    return result

title = "CLIP Aesthetic Score"
description = "Upload an image to predict its aesthetic score using the CLIP model and calculate other image metrics."

gr.Interface(
    fn=predict, 
    inputs=gr.Image(type="numpy"),
    outputs=gr.JSON(label="Result"),
    title=title,
    description=description,
    examples=[["example1.jpg"], ["example2.jpg"]]
).launch()