package main

import (
	"flag"
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
	"strings"
	"time"

	"github.com/denverdino/aliyungo/dns"
)

var client *dns.Client

func main() {
	fmt.Println("Check  Time: " + time.Now().Format("2006-01-02 15:04:05"))
	initClient()
	domainRecord := parseArgs()
	flag.Parse()
	updateDNSRecord(domainRecord)
}

func initClient() {
	id := *flag.String("id", os.Getenv("ALI_DNS_ID"), "AliId")
	key := *flag.String("key", os.Getenv("ALI_DNS_KEY"), "AliKey")

	client = dns.NewClient(id, key)
}

func parseArgs() *dns.AddDomainRecordArgs {
	return &dns.AddDomainRecordArgs{
		DomainName: *flag.String("domain", os.Getenv("ALI_DNS_DOMAIN"), "Domain"),
		RR:         *flag.String("sub", os.Getenv("ALI_DNS_SUB_DOMAIN"), "RR"),
		Type:       *flag.String("type", "A", "RR"),
		Value:      *flag.String("value", getLocalIP(), "Value"),
	}
}

func updateDNSRecord(domainRecord *dns.AddDomainRecordArgs) {
	fmt.Println("Local  IP: " + domainRecord.Value)
	record, err := listRecord(domainRecord)
	if err != nil {
		panic("List Record ERR: " + err.Error())
	}

	if record != nil && record.Value == domainRecord.Value {
		fmt.Println("Record RR: " + domainRecord.RR + " Not Change")
		fmt.Println("Record ID: " + record.RecordId)
		fmt.Println("Record Value: " + domainRecord.Value)
		return
	}

	if record == nil {
		_, err = addRecord(domainRecord)
		fmt.Println("Record RR: " + domainRecord.RR + " Added!")
	} else {
		_, err = updateRecord(record.RecordId, domainRecord)
		fmt.Println("Record RR: " + domainRecord.RR + " Updated!")
		fmt.Println("Record ID: " + record.RecordId)
	}
	fmt.Println("Record Value: " + domainRecord.Value)

	if err != nil {
		fmt.Println("Update Or Add Record ERR: " + err.Error())
	}
}

func getLocalIP() string {
	resp, err := http.Get("http://ip.3322.org")
	if err != nil {
		panic("Get Network IP ERR: " + err.Error())
	}
	str, err := ioutil.ReadAll(resp.Body)
	defer resp.Body.Close()
	if err != nil {
		panic("Read Body Byte ERR: " + err.Error())
	}
	return strings.Replace(string(str), "\n", "", -1)
}

func listRecord(domainRecord *dns.AddDomainRecordArgs) (*dns.RecordTypeNew, error) {
	resp, err := client.DescribeDomainRecordsNew(
		&dns.DescribeDomainRecordsNewArgs{
			DomainName: domainRecord.DomainName,
			RRKeyWord:  domainRecord.RR,
		})
	if err != nil {
		return nil, err
	}
	for _, r := range resp.DomainRecords.Record {
		if r.RR == domainRecord.RR {
			return &r, nil
		}
	}
	return nil, err
}

func addRecord(domainRecord *dns.AddDomainRecordArgs) (*dns.AddDomainRecordResponse, error) {
	return client.AddDomainRecord(domainRecord)
}

func updateRecord(id string, domainRecord *dns.AddDomainRecordArgs) (*dns.UpdateDomainRecordResponse, error) {
	return client.UpdateDomainRecord(&dns.UpdateDomainRecordArgs{
		RecordId: id,
		RR:       domainRecord.RR,
		Type:     domainRecord.Type,
		Value:    domainRecord.Value,
	})
}