package main

import (
	"Watchdog_Linux-systemd/postLog"
	"fmt"
	"net"
)

const (
	listenAddr = "127.0.0.1"
	listenPort = "10080"
	Type       = "tcp"
)

type SoftwareInfo struct {
	Name        string
	Version     string
	Developer   string
	BuildVer    int16
	Description string
	BuildType   string
}

var softwareInfo SoftwareInfo = SoftwareInfo{
	Name:        "Watchdog_Linux-systemd",
	Version:     "0.0.1",
	Developer:   "Super-frpc",
	BuildVer:    1,
	Description: "Super-frpc Watchdog service for Linux systemd",
	BuildType:   "Debug",
}

var isDebug bool

func main() {
	loadConfig()
	if isDebug == true {
		postLog.SetDebugMode(true)
	}
	postLog.Info(fmt.Sprintf("%s %s (Build %d.%s) by %s", softwareInfo.Name, softwareInfo.Version, softwareInfo.BuildVer, softwareInfo.BuildType, softwareInfo.Developer))
	listen, err := net.Listen(Type, fmt.Sprintf("%s:%s", listenAddr, listenPort))
	if err != nil {
		postLog.Fatal(fmt.Sprintf("Failed to listen: %v, err: %v, %v", listenAddr, listenPort, err))
	}
	defer listen.Close()
	postLog.Info(fmt.Sprintf("Server is running on %s:%s", listenAddr, listenPort))

	for {
		conn, err := listen.Accept()
		if err != nil {
			postLog.Error(fmt.Sprintf("Failed to accept: %v, err: %v", conn, err))
		}
		go handleRequest(conn)
	}
}

func handleRequest(conn net.Conn) {
	defer conn.Close()

	buffer := make([]byte, 1024)
	n, err := conn.Read(buffer)
	if err != nil {
		postLog.Error(fmt.Sprintf("Failed to read: %v, err: %v", conn, err))
		return
	}

	recvMsg := string(buffer[:n])
	postLog.Debug(fmt.Sprintf("Received: %v", recvMsg))
	responseMsg := ""
	if recvMsg == "watchdogAgentConnectionTest" {
		responseMsg = "success"
	} else {
		responseMsg = "error: unknown message"
	}
	if _, err := conn.Write([]byte(responseMsg)); err != nil {
		postLog.Error(fmt.Sprintf("Failed to write: %v, err: %v", conn, err))
	}
}