app.py

import gradio as gr
import json, os, time, uuid
from eval_utils import evaluate_submission
from threading import Lock

# Setup
GROUND_TRUTH = "ground_truth.json"
SUB_DIR = "submissions"
RATE_LIMIT = 60
os.makedirs(SUB_DIR, exist_ok=True)
user_last = {}
lock = Lock()


def show_form(profile: gr.OAuthProfile | None):
    visible = profile is not None
    welcome = (f"## 👋 Welcome, {profile.username}! Ready to submit?"
               if visible else "## 🚀 Please sign in to submit.")
    return welcome, gr.Textbox(visible=visible) , gr.File(visible=visible), \
           gr.Checkbox(visible=visible), gr.Button(visible=visible)  


def submit(submission_id: str, submission_file: str, is_private: bool, profile: gr.OAuthProfile | None):
    if not profile:
        raise gr.Error("🔒 Please sign in first.")
    
    username = profile.username
    with lock:
        now = time.time()
        if now - user_last.get(username, 0) < RATE_LIMIT:
            remaining = int(RATE_LIMIT - (now - user_last[username]))
            raise gr.Error(f"⏱️ Wait {remaining}s before retrying.")
        user_last[username] = now

    with open(submission_file.name, "rb") as file:
        prediction_json = json.load(file)
    
    with open(GROUND_TRUTH, "rb") as file:
        ground_truth_json = json.load(file)
    
    score = evaluate_submission(prediction_json, ground_truth_json)

    if not is_private:
        sid = str(uuid.uuid4())
        submission_record = f"{username}_{sid}_{submission_id}"
        json.dump({
            "username": username,
            "identifier": submission_id,
            "timestamp": now,
            "submission": prediction_json
        }, open(os.path.join(SUB_DIR, submission_record + ".json"), "w"))

    return gr.Text(f"{score:.4f}", visible=True)


def get_leaderboard():
    records = []
    # for fn in os.listdir(SUB_DIR):
    #     r = json.load(open(os.path.join(SUB_DIR, fn)))
    #     if not r.get("private", False):
    #         records.append(r)
    records.sort(key=lambda x: -x["score"])
    if not records:
        return "**No submissions yet**"
    lines = ["| User | Score | Time |", "|---|---|---|"]
    for r in records[:10]:
        t = time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(r["timestamp"]))
        lines.append(f"| {r['username']} | {r['score']:.4f} | {t} |")
    return "\n".join(lines)


with gr.Blocks() as demo:
    gr.LoginButton()

    welcome_md = gr.Markdown("Please sign in to be able to submit.")
    submission_file = gr.File(label="Prediction (.json)", visible=False)
    submission_id = gr.Textbox(label="Submission identifier", visible=False)
    private_flag = gr.Checkbox(label="Do not save my submission", value=False, visible=False)
    submit_btn = gr.Button("Submit", visible=False)
    result = gr.Textbox(label="✅ Your score", visible=False)
    leaderboard_heading_md = gr.Markdown("## 🏆 Public Leaderboard")
    leaderboard_md = gr.Markdown(get_leaderboard())

    # Load login state → show/hide components
    demo.load(fn=show_form,
              inputs=[],
              outputs=[welcome_md, submission_id, submission_file, private_flag, submit_btn]) 

    # Submit button only shown post-login
    submit_btn.click(fn=submit,
                     inputs=[submission_id, submission_file, private_flag],
                     outputs=result)

demo.launch()