package service

import (
	"encoding/base64"
	"os"
	"runtime"
	"s-ui/config"
	"s-ui/logger"
	"strconv"
	"strings"
	"time"

	"github.com/sagernet/sing-box/common/tls"
	"github.com/shirou/gopsutil/v3/cpu"
	"github.com/shirou/gopsutil/v3/host"
	"github.com/shirou/gopsutil/v3/mem"
	"github.com/shirou/gopsutil/v3/net"
	"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
)

type ServerService struct{}

func (s *ServerService) GetStatus(request string) *map[string]interface{} {
	status := make(map[string]interface{}, 0)
	requests := strings.Split(request, ",")
	for _, req := range requests {
		switch req {
		case "cpu":
			status["cpu"] = s.GetCpuPercent()
		case "mem":
			status["mem"] = s.GetMemInfo()
		case "net":
			status["net"] = s.GetNetInfo()
		case "sys":
			status["uptime"] = s.GetUptime()
			status["sys"] = s.GetSystemInfo()
		case "sbd":
			status["sbd"] = s.GetSingboxInfo()
		}
	}
	return &status
}

func (s *ServerService) GetCpuPercent() float64 {
	percents, err := cpu.Percent(0, false)
	if err != nil {
		logger.Warning("get cpu percent failed:", err)
		return 0
	} else {
		return percents[0]
	}
}

func (s *ServerService) GetUptime() uint64 {
	upTime, err := host.Uptime()
	if err != nil {
		logger.Warning("get uptime failed:", err)
		return 0
	} else {
		return upTime
	}
}

func (s *ServerService) GetMemInfo() map[string]interface{} {
	info := make(map[string]interface{}, 0)
	memInfo, err := mem.VirtualMemory()
	if err != nil {
		logger.Warning("get virtual memory failed:", err)
	} else {
		info["current"] = memInfo.Used
		info["total"] = memInfo.Total
	}
	return info
}

func (s *ServerService) GetNetInfo() map[string]interface{} {
	info := make(map[string]interface{}, 0)
	ioStats, err := net.IOCounters(false)
	if err != nil {
		logger.Warning("get io counters failed:", err)
	} else if len(ioStats) > 0 {
		ioStat := ioStats[0]
		info["sent"] = ioStat.BytesSent
		info["recv"] = ioStat.BytesRecv
		info["psent"] = ioStat.PacketsSent
		info["precv"] = ioStat.PacketsRecv
	} else {
		logger.Warning("can not find io counters")
	}
	return info
}

func (s *ServerService) GetSingboxInfo() map[string]interface{} {
	var rtm runtime.MemStats
	runtime.ReadMemStats(&rtm)
	isRunning := corePtr.IsRunning()
	uptime := uint32(0)
	if isRunning {
		uptime = corePtr.GetInstance().Uptime()
	}
	return map[string]interface{}{
		"running": isRunning,
		"stats": map[string]interface{}{
			"NumGoroutine": uint32(runtime.NumGoroutine()),
			"Alloc":        rtm.Alloc,
			"Uptime":       uptime,
		},
	}
}

func (s *ServerService) GetSystemInfo() map[string]interface{} {
	info := make(map[string]interface{}, 0)
	var rtm runtime.MemStats
	runtime.ReadMemStats(&rtm)

	info["appMem"] = rtm.Sys
	info["appThreads"] = uint32(runtime.NumGoroutine())
	cpuInfo, err := cpu.Info()
	if err == nil {
		info["cpuType"] = cpuInfo[0].ModelName
	}
	info["cpuCount"] = runtime.NumCPU()
	info["hostName"], _ = os.Hostname()
	info["appVersion"] = config.GetVersion()
	ipv4 := make([]string, 0)
	ipv6 := make([]string, 0)
	// get ip address
	netInterfaces, _ := net.Interfaces()
	for i := 0; i < len(netInterfaces); i++ {
		if len(netInterfaces[i].Flags) > 2 && netInterfaces[i].Flags[0] == "up" && netInterfaces[i].Flags[1] != "loopback" {
			addrs := netInterfaces[i].Addrs

			for _, address := range addrs {
				if strings.Contains(address.Addr, ".") {
					ipv4 = append(ipv4, address.Addr)
				} else if address.Addr[0:6] != "fe80::" {
					ipv6 = append(ipv6, address.Addr)
				}
			}
		}
	}
	info["ipv4"] = ipv4
	info["ipv6"] = ipv6

	return info
}

func (s *ServerService) GetLogs(count string, level string) []string {
	c, _ := strconv.Atoi(count)
	return logger.GetLogs(c, level)
}

func (s *ServerService) GenKeypair(keyType string, options string) []string {
	if len(keyType) == 0 {
		return []string{"No keypair to generate"}
	}

	switch keyType {
	case "ech":
		return s.generateECHKeyPair(options)
	case "tls":
		return s.generateTLSKeyPair(options)
	case "reality":
		return s.generateRealityKeyPair()
	case "wireguard":
		return generateWireGuardKey()
	}

	return []string{"Failed to generate keypair"}
}

func (s *ServerService) generateECHKeyPair(options string) []string {
	parts := strings.Split(options, ",")
	configPem, keyPem, err := tls.ECHKeygenDefault(parts[0], parts[1] == "true")
	if err != nil {
		return []string{"Failed to generate ECH keypair: ", err.Error()}
	}
	return append(strings.Split(configPem, "\n"), strings.Split(keyPem, "\n")...)
}

func (s *ServerService) generateTLSKeyPair(serverName string) []string {
	privateKeyPem, publicKeyPem, err := tls.GenerateKeyPair(time.Now, serverName, time.Now().AddDate(0, 12, 0))
	if err != nil {
		return []string{"Failed to generate TLS keypair: ", err.Error()}
	}
	return append(strings.Split(string(privateKeyPem), "\n"), strings.Split(string(publicKeyPem), "\n")...)
}

func (s *ServerService) generateRealityKeyPair() []string {
	privateKey, err := wgtypes.GeneratePrivateKey()
	if err != nil {
		return []string{"Failed to generate Reality keypair: ", err.Error()}
	}
	publicKey := privateKey.PublicKey()
	return []string{"PrivateKey: " + base64.RawURLEncoding.EncodeToString(privateKey[:]), "PublicKey: " + base64.RawURLEncoding.EncodeToString(publicKey[:])}
}

func generateWireGuardKey() []string {
	privateKey, err := wgtypes.GeneratePrivateKey()
	if err != nil {
		return []string{"Failed to generate wireguard keypair: ", err.Error()}
	}
	return []string{"PrivateKey: " + privateKey.String(), "PublicKey: " + privateKey.PublicKey().String()}
}