package service

import (
	"context"
	"fmt"
	"strconv"
	"time"

	"github.com/1Panel-dev/1Panel/backend/app/model"
	"github.com/1Panel-dev/1Panel/backend/global"
	"github.com/robfig/cron/v3"
	"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/net"
)

type MonitorService struct {
	DiskIO chan ([]disk.IOCountersStat)
	NetIO  chan ([]net.IOCountersStat)
}

var monitorCancel context.CancelFunc

type IMonitorService interface {
	Run()

	saveIODataToDB(ctx context.Context, interval float64)
	saveNetDataToDB(ctx context.Context, interval float64)
}

func NewIMonitorService() IMonitorService {
	return &MonitorService{
		DiskIO: make(chan []disk.IOCountersStat, 2),
		NetIO:  make(chan []net.IOCountersStat, 2),
	}
}

func (m *MonitorService) Run() {
	var itemModel model.MonitorBase
	totalPercent, _ := cpu.Percent(3*time.Second, false)
	if len(totalPercent) == 1 {
		itemModel.Cpu = totalPercent[0]
	}
	cpuCount, _ := cpu.Counts(false)

	loadInfo, _ := load.Avg()
	itemModel.CpuLoad1 = loadInfo.Load1
	itemModel.CpuLoad5 = loadInfo.Load5
	itemModel.CpuLoad15 = loadInfo.Load15
	itemModel.LoadUsage = loadInfo.Load1 / (float64(cpuCount*2) * 0.75) * 100

	memoryInfo, _ := mem.VirtualMemory()
	itemModel.Memory = memoryInfo.UsedPercent

	if err := settingRepo.CreateMonitorBase(itemModel); err != nil {
		global.LOG.Errorf("Insert basic monitoring data failed, err: %v", err)
	}

	m.loadDiskIO()
	m.loadNetIO()

	MonitorStoreDays, err := settingRepo.Get(settingRepo.WithByKey("MonitorStoreDays"))
	if err != nil {
		return
	}
	storeDays, _ := strconv.Atoi(MonitorStoreDays.Value)
	timeForDelete := time.Now().AddDate(0, 0, -storeDays)
	_ = settingRepo.DelMonitorBase(timeForDelete)
	_ = settingRepo.DelMonitorIO(timeForDelete)
	_ = settingRepo.DelMonitorNet(timeForDelete)
}

func (m *MonitorService) loadDiskIO() {
	ioStat, _ := disk.IOCounters()
	var diskIOList []disk.IOCountersStat
	for _, io := range ioStat {
		diskIOList = append(diskIOList, io)
	}
	m.DiskIO <- diskIOList
}

func (m *MonitorService) loadNetIO() {
	netStat, _ := net.IOCounters(true)
	netStatAll, _ := net.IOCounters(false)
	var netList []net.IOCountersStat
	netList = append(netList, netStat...)
	netList = append(netList, netStatAll...)
	m.NetIO <- netList
}

func (m *MonitorService) saveIODataToDB(ctx context.Context, interval float64) {
	defer close(m.DiskIO)
	for {
		select {
		case <-ctx.Done():
			return
		case ioStat := <-m.DiskIO:
			select {
			case <-ctx.Done():
				return
			case ioStat2 := <-m.DiskIO:
				var ioList []model.MonitorIO
				for _, io2 := range ioStat2 {
					for _, io1 := range ioStat {
						if io2.Name == io1.Name {
							var itemIO model.MonitorIO
							itemIO.Name = io1.Name
							if io2.ReadBytes != 0 && io1.ReadBytes != 0 && io2.ReadBytes > io1.ReadBytes {
								itemIO.Read = uint64(float64(io2.ReadBytes-io1.ReadBytes) / interval / 60)
							}
							if io2.WriteBytes != 0 && io1.WriteBytes != 0 && io2.WriteBytes > io1.WriteBytes {
								itemIO.Write = uint64(float64(io2.WriteBytes-io1.WriteBytes) / interval / 60)
							}

							if io2.ReadCount != 0 && io1.ReadCount != 0 && io2.ReadCount > io1.ReadCount {
								itemIO.Count = uint64(float64(io2.ReadCount-io1.ReadCount) / interval / 60)
							}
							writeCount := uint64(0)
							if io2.WriteCount != 0 && io1.WriteCount != 0 && io2.WriteCount > io1.WriteCount {
								writeCount = uint64(float64(io2.WriteCount-io1.WriteCount) / interval * 60)
							}
							if writeCount > itemIO.Count {
								itemIO.Count = writeCount
							}

							if io2.ReadTime != 0 && io1.ReadTime != 0 && io2.ReadTime > io1.ReadTime {
								itemIO.Time = uint64(float64(io2.ReadTime-io1.ReadTime) / interval / 60)
							}
							writeTime := uint64(0)
							if io2.WriteTime != 0 && io1.WriteTime != 0 && io2.WriteTime > io1.WriteTime {
								writeTime = uint64(float64(io2.WriteTime-io1.WriteTime) / interval / 60)
							}
							if writeTime > itemIO.Time {
								itemIO.Time = writeTime
							}
							ioList = append(ioList, itemIO)
							break
						}
					}
				}
				if err := settingRepo.BatchCreateMonitorIO(ioList); err != nil {
					global.LOG.Errorf("Insert io monitoring data failed, err: %v", err)
				}
				m.DiskIO <- ioStat2
			}
		}
	}
}

func (m *MonitorService) saveNetDataToDB(ctx context.Context, interval float64) {
	defer close(m.NetIO)
	for {
		select {
		case <-ctx.Done():
			return
		case netStat := <-m.NetIO:
			select {
			case <-ctx.Done():
				return
			case netStat2 := <-m.NetIO:
				var netList []model.MonitorNetwork
				for _, net2 := range netStat2 {
					for _, net1 := range netStat {
						if net2.Name == net1.Name {
							var itemNet model.MonitorNetwork
							itemNet.Name = net1.Name

							if net2.BytesSent != 0 && net1.BytesSent != 0 && net2.BytesSent > net1.BytesSent {
								itemNet.Up = float64(net2.BytesSent-net1.BytesSent) / 1024 / interval / 60
							}
							if net2.BytesRecv != 0 && net1.BytesRecv != 0 && net2.BytesRecv > net1.BytesRecv {
								itemNet.Down = float64(net2.BytesRecv-net1.BytesRecv) / 1024 / interval / 60
							}
							netList = append(netList, itemNet)
							break
						}
					}
				}

				if err := settingRepo.BatchCreateMonitorNet(netList); err != nil {
					global.LOG.Errorf("Insert network monitoring data failed, err: %v", err)
				}
				m.NetIO <- netStat2
			}
		}
	}
}

func StartMonitor(removeBefore bool, interval string) error {
	if removeBefore {
		monitorCancel()
		global.Cron.Remove(cron.EntryID(global.MonitorCronID))
	}
	intervalItem, err := strconv.Atoi(interval)
	if err != nil {
		return err
	}

	service := NewIMonitorService()
	ctx, cancel := context.WithCancel(context.Background())
	monitorCancel = cancel
	now := time.Now()
	nextMinute := now.Truncate(time.Minute).Add(time.Minute)
	time.AfterFunc(time.Until(nextMinute), func() {
		monitorID, err := global.Cron.AddJob(fmt.Sprintf("@every %sm", interval), service)
		if err != nil {
			return
		}
		global.MonitorCronID = monitorID
	})
	service.Run()

	go service.saveIODataToDB(ctx, float64(intervalItem))
	go service.saveNetDataToDB(ctx, float64(intervalItem))

	return nil
}