const express = require('express');
const os = require('os');
const router = express.Router();

router.get('/', (req, res) => {
    // Get CPU usage
    const cpus = os.cpus();
    let totalIdle = 0;
    let totalTick = 0;
    
    cpus.forEach(cpu => {
        // Calculate idle time and total time for each CPU core
        const idle = cpu.times.idle;
        const user = cpu.times.user;
        const nice = cpu.times.nice;
        const sys = cpu.times.sys;
        const irq = cpu.times.irq;
        
        // Calculate total time by summing all CPU states
        const total = user + nice + sys + idle + irq;
        
        // Add to running totals to get average across all cores
        totalTick += total;
        totalIdle += idle;
    });

    const cpuUsage = 100 - (totalIdle / totalTick * 100);

    // Get memory usage
    const totalMemory = os.totalmem() / 1024 / 1024 / 1024;

    const freeMemory = os.freemem()  / 1024 / 1024 / 1024;
    const usedMemory = totalMemory - freeMemory;
    const memoryUsage = (usedMemory / totalMemory * 100);

    res.json({
        cpu: Math.round(cpuUsage * 100) / 100,
        memory: Math.round(memoryUsage * 100) / 100,
        totalMemory: totalMemory.toFixed(2),
        freeMemory: freeMemory.toFixed(2)
    });
});

module.exports = router;