package system

import (
	"fmt"
	"github.com/shirou/gopsutil/v3/cpu"
	"github.com/shirou/gopsutil/v3/disk"
	"github.com/shirou/gopsutil/v3/mem"
)

func Info() string {
	d := Disk()
	m := Mem()
	return SIToString(&d, &m, CpuPercent())
}

func SIToString(d *DiskPath, m *MemInfo, cpuPercent float64) string {
	in := fmt.Sprintf("Cpu=> UsedPercent: %.2f\r\n"+
		"Memory=> Total: %v, Available: %v, Used: %v, UsedPercent: %.2f\r\n"+
		"Disk=> Path: %v, Total: %v, Free: %v, Used: %v, UsedPercent: %.2f\r\n",
		cpuPercent,
		m.Total, m.Available, m.Used, m.UsedPercent,
		d.Path, d.Total, d.Free, d.Used, d.UsedPercent)
	return in
}

const GB = 1024 * 1024 * 1024

func Mem() MemInfo {

	v, er := mem.VirtualMemory()
	if er != nil {
		return MemInfo{}
	}
	return MemInfo{
		Total:       v.Total / GB,
		Available:   v.Available / GB,
		Used:        v.Used / GB,
		UsedPercent: v.UsedPercent,
	}
}

type MemInfo struct {
	// Total amount of RAM on this system
	Total uint64 `json:"total"`

	// RAM available for programs to allocate
	//
	// This value is computed from the kernel specific values.
	Available uint64 `json:"available"`

	// RAM used by programs
	//
	// This value is computed from the kernel specific values.
	Used uint64 `json:"used"`

	// Percentage of RAM used by programs
	//
	// This value is computed from the kernel specific values.
	UsedPercent float64 `json:"usedPercent"`
}

func CpuPercent() float64 {
	in, er := cpu.Percent(0, false)
	if er != nil {
		return 0
	}
	return in[0]
}

func Cpu() CpuInfo {
	in, er := cpu.Times(false) //(0*time.Second, false)
	if er != nil {
		return CpuInfo{}
	}
	var inf CpuInfo
	for i := range in {
		inf.User = in[i].User
		inf.System = in[i].System
		inf.Idle = in[i].Idle
		inf.Nice = in[i].Nice
	}
	return inf
}

type CpuInfo struct {
	User   float64 `json:"user"`
	System float64 `json:"system"`
	Idle   float64 `json:"idle"`
	Nice   float64 `json:"nice"`
}

func Disk() DiskPath {
	return DiskWithPath("/")
}

func DiskWithPath(path string) DiskPath {
	d, err := disk.Usage(path)
	if err != nil {
		return DiskPath{}
	}
	return DiskPath{
		Path:        d.Path,
		Total:       d.Total / GB,
		Free:        d.Free / GB,
		Used:        d.Used / GB,
		UsedPercent: d.UsedPercent,
	}
}

func DiskAll() []DiskPath {
	var paths []DiskPath
	part, er := disk.Partitions(false)
	if er != nil {
		return paths
	}
	for i := range part {
		if d, err := disk.Usage(part[i].Mountpoint); err == nil {
			var dp = DiskPath{
				Path:        d.Path,
				Total:       d.Total / GB,
				Free:        d.Free / GB,
				Used:        d.Used / GB,
				UsedPercent: d.UsedPercent,
			}
			if dp.Total > 0 {
				paths = append(paths, dp)
			}
		}
	}
	return paths
}

type DiskPath struct {
	Path        string  `json:"path,omitempty"`
	Total       uint64  `json:"total"`
	Free        uint64  `json:"free"`
	Used        uint64  `json:"used"`
	UsedPercent float64 `json:"usedPercent"`
}