// server/services/system.ts
import os from "node:os";
import type { SystemMetrics, SystemStatus } from "@shared/types.js";

const APP_VERSION = "0.1.0";
const MB = 1024 * 1024;

function round2(value: number): number {
  return Math.round(value * 100) / 100;
}

export function getSystemStatus(now = new Date()): SystemStatus {
  return {
    app: "system_update",
    version: APP_VERSION,
    apiVersion: "1",
    serverTime: now.toISOString(),
    uptimeSeconds: Math.round(process.uptime()),
  };
}

export function getSystemMetrics(now = new Date()): SystemMetrics {
  const memory = process.memoryUsage();
  const load = os.loadavg();

  return {
    collectedAt: now.toISOString(),
    process: {
      uptimeSeconds: Math.round(process.uptime()),
      rssMb: round2(memory.rss / MB),
      heapUsedMb: round2(memory.heapUsed / MB),
      heapTotalMb: round2(memory.heapTotal / MB),
    },
    host: {
      loadAverage1m: round2(load[0] ?? 0),
      loadAverage5m: round2(load[1] ?? 0),
      loadAverage15m: round2(load[2] ?? 0),
      totalMemoryMb: round2(os.totalmem() / MB),
      freeMemoryMb: round2(os.freemem() / MB),
    },
  };
}

export const systemInternals = { round2 };