import os
import time
import hashlib
import platform

import requests

ID_FILE = "/data/egg_id"


def generate_trial():
    """Sum of 200 random bits drawn from the OS CSPRNG (hardware entropy pool)."""
    raw = os.urandom(25)  # 25 bytes = 200 bits
    return sum(bin(b).count("1") for b in raw)


def load_or_create_id():
    try:
        with open(ID_FILE) as f:
            egg_id = f.read().strip()
            if egg_id:
                return egg_id
    except OSError:
        pass
    egg_id = hashlib.sha256(os.urandom(32)).hexdigest()[:16]
    try:
        os.makedirs("/data", exist_ok=True)
        with open(ID_FILE, "w") as f:
            f.write(egg_id)
    except OSError:
        pass
    return egg_id


def main():
    server_url = os.environ.get("SERVER_URL", "http://localhost:8000").rstrip("/")
    egg_id = os.environ.get("EGG_ID") or load_or_create_id()

    print(f"GCP Egg  id={egg_id}  server={server_url}  platform={platform.system()}")

    session = requests.Session()
    errors = 0

    while True:
        loop_start = time.time()
        timestamp = int(loop_start)
        trial = generate_trial()

        try:
            resp = session.post(
                f"{server_url}/api/data",
                json={"egg_id": egg_id, "timestamp": timestamp, "trial": trial},
                timeout=5,
            )
            if resp.status_code == 200:
                errors = 0
            else:
                errors += 1
                if errors % 10 == 1:
                    print(f"Server returned {resp.status_code} (error #{errors})")
        except Exception as exc:
            errors += 1
            if errors % 10 == 1:
                print(f"Send error (#{errors}): {exc}")

        elapsed = time.time() - loop_start
        time.sleep(max(0.0, 1.0 - elapsed))


if __name__ == "__main__":
    main()