from fastapi import FastAPI
from fastapi.responses import JSONResponse
import time
import psutil
import os

app = FastAPI()

process = psutil.Process(os.getpid())
last_cpu_times = process.cpu_times()
last_time = time.time()

def get_cpu_percent():

    global last_cpu_times, last_time
    now = time.time()
    times = process.cpu_times()
    elapsed = now - last_time
    cpu_used = (times.user - last_cpu_times.user) + (times.system - last_cpu_times.system)
    last_cpu_times = times
    last_time = now

    return round((cpu_used / elapsed) * 100, 1)

def simulate_work():

    start = time.time()
    while (time.time() - start) < 0.005:
        pass

@app.get("/")
async def root():
    simulate_work()
    return {"ok": True, "time": int(time.time() * 1000)}

@app.get("/metrics")
async def metrics():
    try:
        cpu_percent = get_cpu_percent()
        mem_info = process.memory_info()
        return {
            "cpu": cpu_percent,
            "memory": round(mem_info.rss / 1024 / 1024, 1)
        }
    except Exception as e:
        return JSONResponse(status_code=500, content={"error": str(e)})

if __name__ == "__main__":
    port = int(os.environ.get("PORT", 3000))
    print(f"✅ FastAPI server running on port {port}")
    import uvicorn
    uvicorn.run("main:app", host="0.0.0.0", port=port, log_level="info")