from fastapi import FastAPI
from fastapi.responses import HTMLResponse, JSONResponse
from fastapi.staticfiles import StaticFiles
import random, threading, time

app = FastAPI()

# Serve static and HTML files
app.mount("/static", StaticFiles(directory="static"), name="static")

# Initialize game grid
GRID = [random.randint(0,9) for _ in range(9)]
LOCK = threading.Lock()

# Track start time to gradually reduce the interval
START_TIME = time.time()

# Get interval from 3s down to 0.5s over 120s
# Then remain at 0.5s thereafter

def get_interval():
    elapsed = time.time() - START_TIME
    # linear from t=0 => 3s, t=120 => 0.5s
    # interval(t) = -1/48 * t + 3, clamped to min 0.5
    return max(0.5, -elapsed / 48 + 3)

# Randomly change one number every get_interval() seconds

def change_number():
    global GRID
    while True:
        print("Changing a number in flipnum...")
        with LOCK:
            idx = random.randint(0, 8)
            old_num = GRID[idx]
            new_num = random.choice([x for x in range(10) if x != old_num])
            GRID[idx] = new_num
        time.sleep(get_interval())

@app.on_event("startup")
def startup_event():
    threading.Thread(target=change_number, daemon=True).start()

@app.get("/", response_class=HTMLResponse)
def index():
    with open("static/index.html") as f:
        return f.read()

@app.get("/get_grid")
def get_grid():
    with LOCK:
        return JSONResponse(GRID)