app.py

import gradio as gr
from PIL import Image
import onnxruntime as ort
import torchvision.transforms as transforms
import json
import os
import numpy as np
import pandas as pd
import random
from huggingface_hub import snapshot_download, HfApi
from transformers import CLIPTokenizer

# --- Config ---
HUB_REPO_ID = "aarodi/OpenArenaLeaderboard"
HF_TOKEN = os.environ.get("HF_TOKEN")
LOCAL_JSON = "leaderboard.json"
HUB_JSON = "leaderboard.json"
MODEL_PATH = "mobilenet_v2_fake_detector.onnx"
CLIP_IMAGE_ENCODER_PATH = "clip_image_encoder.onnx"
CLIP_TEXT_ENCODER_PATH = "clip_text_encoder.onnx"
PROMPT_CSV_PATH = "generate2_1.csv"
PROMPT_MATCH_THRESHOLD = 10  # percent

# --- Download leaderboard + model checkpoint from HF Hub ---
def load_assets():
    try:
        snapshot_download(
            repo_id=HUB_REPO_ID,
            local_dir=".",
            repo_type="dataset",
            token=HF_TOKEN,
            allow_patterns=[HUB_JSON, MODEL_PATH, CLIP_IMAGE_ENCODER_PATH, CLIP_TEXT_ENCODER_PATH, PROMPT_CSV_PATH]
        )
    except Exception as e:
        print(f"Failed to load assets from HF Hub: {e}")

load_assets()

# --- Load prompts from CSV ---
def load_prompts():
    try:
        df = pd.read_csv(PROMPT_CSV_PATH)
        if "prompt" in df.columns:
            return df["prompt"].dropna().tolist()
        else:
            print("CSV missing 'prompt' column.")
            return []
    except Exception as e:
        print(f"Failed to load prompts: {e}")
        return []

PROMPT_LIST = load_prompts()

# --- Load leaderboard ---
def load_leaderboard():
    try:
        with open(HUB_JSON, "r") as f:
            return json.load(f)
    except Exception as e:
        print(f"Failed to read leaderboard: {e}")
        return {}

leaderboard_scores = load_leaderboard()

# --- Save and push to HF Hub ---
def save_leaderboard():
    try:
        with open(HUB_JSON, "w") as f:
            json.dump(leaderboard_scores, f)

        if HF_TOKEN is None:
            print("HF_TOKEN not set. Skipping push to hub.")
            return

        api = HfApi()
        api.upload_file(
            path_or_fileobj=HUB_JSON,
            path_in_repo=HUB_JSON,
            repo_id=HUB_REPO_ID,
            repo_type="dataset",
            token=HF_TOKEN,
            commit_message="Update leaderboard"
        )
    except Exception as e:
        print(f"Failed to save leaderboard to HF Hub: {e}")

# --- Load ONNX models ---
session = ort.InferenceSession(MODEL_PATH, providers=["CPUExecutionProvider"])
input_name = session.get_inputs()[0].name

clip_image_sess = ort.InferenceSession(CLIP_IMAGE_ENCODER_PATH, providers=["CPUExecutionProvider"])
clip_text_sess = ort.InferenceSession(CLIP_TEXT_ENCODER_PATH, providers=["CPUExecutionProvider"])
clip_tokenizer = CLIPTokenizer.from_pretrained("openai/clip-vit-base-patch32")

transform = transforms.Compose([
    transforms.Resize((224, 224)),
    transforms.ToTensor(),
    transforms.Normalize(mean=[0.48145466, 0.4578275, 0.40821073], std=[0.26862954, 0.26130258, 0.27577711])
])

def compute_prompt_match(image: Image.Image, prompt: str) -> float:
    try:
        img_tensor = transform(image).unsqueeze(0).numpy().astype(np.float32)
        image_features = clip_image_sess.run(None, {clip_image_sess.get_inputs()[0].name: img_tensor})[0][0]
        image_features /= np.linalg.norm(image_features)

        inputs = clip_tokenizer(prompt, return_tensors="np", padding="max_length", truncation=True, max_length=77)
        input_ids = inputs["input_ids"]
        attention_mask = inputs["attention_mask"]
        text_features = clip_text_sess.run(None, {
            clip_text_sess.get_inputs()[0].name: input_ids,
            clip_text_sess.get_inputs()[1].name: attention_mask
        })[0][0]
        text_features /= np.linalg.norm(text_features)

        sim = np.dot(image_features, text_features)
        return round(sim * 100, 2)
    except Exception as e:
        print(f"CLIP ONNX match failed: {e}")
        return 0.0

# --- Main prediction logic ---
def detect_with_model(image: Image.Image, prompt: str, username: str):
    if not username.strip():
        return "Please enter your name.", None, [], gr.update(visible=True), gr.update(visible=False)

    prompt_score = compute_prompt_match(image, prompt)
    if prompt_score < PROMPT_MATCH_THRESHOLD:
        message = f"⚠️ Prompt match too low ({round(prompt_score, 2)}%). Please generate an image that better matches the prompt."
        return message, None, [], gr.update(visible=True), gr.update(visible=False)

    image_tensor = transforms.Resize((224, 224))(image)
    image_tensor = transforms.ToTensor()(image_tensor).unsqueeze(0).numpy().astype(np.float32)
    outputs = session.run(None, {input_name: image_tensor})
    prob = round(1 / (1 + np.exp(-outputs[0][0][0])), 2)
    prediction = "Real" if prob > 0.5 else "Fake"

    score = 1 if prediction == "Real" else 0
    confidence = round(prob * 100, 2) if prediction == "Real" else round((1 - prob) * 100, 2)

    message = f"Prediction: {prediction} ({confidence}% confidence)\n🧐 Prompt match: {prompt_score}%"

    if prediction == "Real":
        leaderboard_scores[username] = leaderboard_scores.get(username, 0) + score
        message += "\n🎉 Nice! You fooled the AI. +1 point!"
    else:
        message += "\n😅 The AI caught you this time. Try again!"

    save_leaderboard()

    sorted_scores = sorted(leaderboard_scores.items(), key=lambda x: x[1], reverse=True)
    leaderboard_table = [[name, points] for name, points in sorted_scores]

    return (
        message,
        image,
        leaderboard_table,
        gr.update(visible=False),
        gr.update(visible=True)
    )

# --- UI Layout ---
def get_random_prompt():
    return random.choice(PROMPT_LIST) if PROMPT_LIST else "A synthetic scene with dramatic lighting"

with gr.Blocks(css=".gr-button {font-size: 16px !important}") as demo:
    gr.Markdown("## 🎝 OpenFake Arena")
    gr.Markdown("Welcome to the OpenFake Arena!\n\n**Your mission:** Generate a synthetic image for the prompt, upload it, and try to fool the AI detector into thinking it’s real.\n\n**Rules:**\n- Only synthetic images allowed!\n- No cheating with real photos.\n- Licensing is your responsibility.\n\nMake it wild. Make it weird. Most of all — make it fun.")

    with gr.Group(visible=True) as input_section:
        username_input = gr.Textbox(label="Your Name", placeholder="Enter your name")

        with gr.Row():
            prompt_input = gr.Textbox(
                label="Suggested Prompt",
                placeholder="e.g., A portrait photograph of a politician delivering a speech...",
                value=get_random_prompt(),
                lines=2
            )

        with gr.Row():
            image_input = gr.Image(type="pil", label="Upload Synthetic Image")

        with gr.Row():
            submit_btn = gr.Button("Upload")

    try_again_btn = gr.Button("Try Again", visible=False)

    with gr.Group():
        gr.Markdown("### 🎯 Result")
        with gr.Row():
            prediction_output = gr.Textbox(label="Prediction", interactive=False)
            image_output = gr.Image(label="Submitted Image", show_label=False)

    with gr.Group():
        gr.Markdown("### 🏆 Leaderboard")
        leaderboard = gr.Dataframe(
            headers=["Username", "Score"],
            datatype=["str", "number"],
            interactive=False,
            row_count=5
        )

    submit_btn.click(
        fn=detect_with_model,
        inputs=[image_input, prompt_input, username_input],
        outputs=[
            prediction_output,
            image_output,
            leaderboard,
            input_section,
            try_again_btn
        ]
    )

    try_again_btn.click(
        fn=lambda: ("", None, [], gr.update(visible=True), gr.update(visible=False)),
        outputs=[
            prediction_output,
            image_output,
            leaderboard,
            input_section,
            try_again_btn
        ]
    )

if __name__ == "__main__":
    demo.launch()