package metrics

import (
	"os"
	"runtime"
	"strconv"
	"strings"

	"github.com/shirou/gopsutil/v3/cpu"
	"github.com/shirou/gopsutil/v3/disk"
	"github.com/shirou/gopsutil/v3/load"
	"github.com/shirou/gopsutil/v3/mem"
	"github.com/shirou/gopsutil/v3/host"
)

type Snapshot struct {
	CPUPercent    float64
	MemoryPercent float64
	MemoryUsed    uint64
	MemoryTotal   uint64
	DiskPercent   float64
	DiskUsed      uint64
	DiskTotal     uint64
	Load1         float64
	Load5         float64
	Load15        float64
	UptimeSeconds uint64
}

func Collect() (*Snapshot, error) {
	s := &Snapshot{}

	if percents, err := cpu.Percent(0, false); err == nil && len(percents) > 0 {
		s.CPUPercent = percents[0]
	}

	if v, err := mem.VirtualMemory(); err == nil {
		s.MemoryPercent = v.UsedPercent
		s.MemoryUsed = v.Used
		s.MemoryTotal = v.Total
	}

	if d, err := disk.Usage("/"); err == nil {
		s.DiskPercent = d.UsedPercent
		s.DiskUsed = d.Used
		s.DiskTotal = d.Total
	}

	if avg, err := load.Avg(); err == nil {
		s.Load1 = avg.Load1
		s.Load5 = avg.Load5
		s.Load15 = avg.Load15
	}

	if up, err := host.Uptime(); err == nil {
		s.UptimeSeconds = up
	}

	if runtime.GOOS == "linux" {
		if data, err := os.ReadFile("/proc/loadavg"); err == nil {
			fields := strings.Fields(string(data))
			if len(fields) >= 3 {
				s.Load1, _ = strconv.ParseFloat(fields[0], 64)
				s.Load5, _ = strconv.ParseFloat(fields[1], 64)
				s.Load15, _ = strconv.ParseFloat(fields[2], 64)
			}
		}
	}

	return s, nil
}