import requests
import time
import pandas as pd
import gradio as gr
from fastapi import FastAPI
import threading

app = FastAPI()

URL = "https://histdatafeed.vps.com.vn/tradingview/history"

# ===== CACHE GLOBAL =====
latest_data = None
latest_signal = None
last_update = 0

# ===== FETCH DATA =====
def fetch_data():
    global latest_data, last_update

    try:
        params = {
            "symbol": "VN30F1M",
            "resolution": "1",
            "from": int(time.time()) - 3600,
            "to": int(time.time()),
            "countback": 200
        }

        res = requests.get(URL, params=params, timeout=5)
        data = res.json()

        df = pd.DataFrame({
            "time": data["t"],
            "open": data["o"],
            "high": data["h"],
            "low": data["l"],
            "close": data["c"],
            "volume": data["v"]
        })

        latest_data = df
        last_update = time.time()

    except Exception as e:
        print("Fetch error:", e)

# ===== AI SIGNAL =====
def compute_signal():
    global latest_data, latest_signal

    if latest_data is None or len(latest_data) < 20:
        return "WAIT"

    df = latest_data.copy()
    df["ma20"] = df["close"].rolling(20).mean()

    if df["close"].iloc[-1] > df["ma20"].iloc[-1]:
        latest_signal = "BUY"
    else:
        latest_signal = "SELL"

# ===== HEARTBEAT LOOP =====
def heartbeat():
    while True:
        fetch_data()
        compute_signal()
        print("Heartbeat update:", latest_signal)
        time.sleep(10)  # 10s update

threading.Thread(target=heartbeat, daemon=True).start()

# ===== API =====
@app.get("/signal")
def signal():
    return {
        "signal": latest_signal,
        "price": float(latest_data["close"].iloc[-1]) if latest_data is not None else 0,
        "time": int(last_update)
    }

# ===== UI =====
def ui():
    return f"Signal: {latest_signal} | Updated: {int(last_update)}"

interface = gr.Interface(
    fn=ui,
    inputs=[],
    outputs="text",
    live=True
).queue()

app = gr.mount_gradio_app(app, interface, path="/")