package main

import (
	"fmt"
	"github.com/gocarina/gocsv"
	"io"
	"log"
	"net"
	"net/http"
	"os"
	"strconv"
	"strings"
	"time"
)

func main() {
	monitorsFile, err := os.OpenFile(OUTPUTFILE, os.O_RDWR|os.O_CREATE, os.ModePerm)
	if err != nil {
		panic(err)
	}
	defer monitorsFile.Close()
	monitors := []*Monitor{}

	hosts, err := GetHostListFromCSV()
	if err != nil {
		fmt.Println(err)
	}
	totalHosts := len(hosts)
	count := 0
	log.Println("本次要处理主机数量： ", totalHosts)
	for _, host := range hosts {
		fmt.Println(host)
		var errorflag string
		serverIP := strClean(host.IP)
		if !isTCPOpen(serverIP, host.Port) {
			count += 1
			log.Println(count, "/", totalHosts, "端口不通: ", serverIP, host.Port)
			continue
		}
		cpuCore, cpuUsage, err1 := getCPUInfo(serverIP, host.Port)
		memTotal, memUsage, err2 := getMemoryInfo(serverIP, host.Port)
		nodeLoad1, nodeLoad5, nodeLoad15, err3 := getLoadInfo(serverIP, host.Port)
		if err1 != nil || err2 != nil || err3 != nil {
			fmt.Println("host error: ", err)
			errorflag = "error"
		}

		monitors = append(monitors, &Monitor{
			IP:         serverIP,
			Port:       host.Port,
			CPUCore:    cpuCore,
			CPUUsage:   cpuUsage,
			MemTotal:   memTotal,
			MemUsage:   memUsage,
			NodeLoad1:  nodeLoad1,
			NodeLoad5:  nodeLoad5,
			NodeLoad15: nodeLoad15,
			ERROR:      errorflag,
		})
		count += 1
		log.Println(count, "/", totalHosts, " handled: ", serverIP)
	}

	err = gocsv.MarshalFile(&monitors, monitorsFile) // Use this to save the CSV back to the file
	if err != nil {
		panic(err)
	}

}

func getMetrics(ip, port string) (string, error) {
	// 发送HTTP请求获取Node Exporter的metrics数据
	address := "http://" + ip + ":" + port + "/metrics"
	response, err := http.Get(address)
	if err != nil {
		log.Println("无法发送HTTP请求：", err)
		//log.Fatal("无法发送HTTP请求：", err)
		return "", err
	}
	defer response.Body.Close()

	// 读取响应内容
	body, err := io.ReadAll(response.Body)
	if err != nil {
		log.Println("无法读取响应内容：", err)
		//log.Fatal("无法读取响应内容：", err)
		return "", err
	}
	return string(body), nil

}

// 从指标行中提取指标值，并将其转换为浮点数类型
func extractMetricValue(value string) (float64, error) {
	// 去除指标值的单位（此处假设单位为'count'）
	value = strings.Split(value, " ")[0]
	// 将指标值转换为浮点数类型并返回
	return parseFloat(value)
}

// 将字符串转换为浮点数类型，并处理可能的错误情况
func parseFloat(value string) (float64, error) {
	f, err := strconv.ParseFloat(value, 64)
	if err != nil {
		return 0, err
	}
	return f, nil
}

func strClean(str string) string {
	str = strings.ReplaceAll(str, " ", "")
	str = strings.ReplaceAll(str, ",", "")
	str = strings.ReplaceAll(str, "\"", "")
	return str
}

func isTCPOpen(ip, port string) bool {
	// 尝试在指定端口上建立连接
	address := ip + ":" + port
	conn, err := net.DialTimeout("tcp", address, time.Millisecond*10)
	if err != nil {
		return false
	}
	defer conn.Close()
	return true
}