from flask import Flask
import time, random, threading

app = Flask(__name__)

# --- Metrics (thread-safe counters) ---
lock = threading.Lock()
metrics = {
    "requests_total": 0,
    "errors_total": 0,
    "duration_sum": 0.0,
    "duration_count": 0,
}

@app.route('/')
def home():
    start = time.time()

    # Simuleer latency
    time.sleep(random.uniform(0.1, 2.0))

    # Simuleer 10% errors
    is_error = random.random() < 0.1
    duration = time.time() - start

    with lock:
        metrics["requests_total"] += 1
        metrics["duration_sum"] += duration
        metrics["duration_count"] += 1
        if is_error:
            metrics["errors_total"] += 1

    if is_error:
        return "Oeps!", 500
    return "Welkom bij de shop!"

@app.route('/metrics')
def get_metrics():
    with lock:
        avg_duration = (
            metrics["duration_sum"] / metrics["duration_count"]
            if metrics["duration_count"] > 0 else 0
        )
        error_rate = (
            metrics["errors_total"] / metrics["requests_total"] * 100
            if metrics["requests_total"] > 0 else 0
        )
        return {
            "requests_total":  metrics["requests_total"],
            "errors_total":    metrics["errors_total"],
            "error_rate_pct":  round(error_rate, 2),
            "avg_duration_sec": round(avg_duration, 3),
        }

app.run(host='0.0.0.0', port=5000)