package aws

import (
	"errors"

	"git.trj.tw/golang/go-ddns-svc/module/config"
	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/credentials"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/route53"
)

// AWSClient -
type AWSClient struct {
	Session *session.Session
	Config  *aws.Config
	R53     *route53.Route53
}

var client *AWSClient

// Error messages
var (
	ErrNoClient = errors.New("client not init")
	ErrNoZone   = errors.New("no hosted zones")
)

// NewAWS -
func NewAWS() error {
	conf := config.GetConfig()
	awsConf := &aws.Config{}
	awsConf.Region = aws.String("us-east-1")
	var sess *session.Session

	if conf.AWS.SharedConfig {
		if len(conf.AWS.SharedName) == 0 {
			return errors.New("aws shared config name empty")
		}
		awsConf.Credentials = credentials.NewSharedCredentials("", conf.AWS.SharedName)
	} else {
		awsConf.Credentials = credentials.NewStaticCredentials(conf.AWS.AccessKey, conf.AWS.SecretKey, "")
	}
	sess = session.New(awsConf)

	client = &AWSClient{}
	client.Session = sess
	client.Config = awsConf
	client.R53 = route53.New(client.Session)

	return nil
}

// ZoneData -
type ZoneData struct {
	ID   *string
	Name string
}

// QueryDomain -
func QueryDomain(name []string) ([]*ZoneData, error) {
	if client == nil {
		return nil, ErrNoClient
	}
	domains := make([]string, 0, len(name))
	if len(name) == 0 {
		return nil, errors.New("no input domain name")
	}
	for _, n := range name {
		if len(n) > 0 {
			if n[len(n)-1:] != "." {
				n += "."
			}
			domains = append(domains, n)
		}
	}
	if len(domains) == 0 {
		return nil, errors.New("no input domain name")
	}

	input := &route53.ListHostedZonesInput{}
	zoneOut, err := client.R53.ListHostedZones(input)
	if err != nil {
		return nil, err
	}
	if len(zoneOut.HostedZones) == 0 {
		return nil, ErrNoZone
	}

	zones := make([]*ZoneData, 0)
	for _, it := range zoneOut.HostedZones {
		for _, domain := range domains {
			if *it.Name == domain {
				zone := &ZoneData{
					ID:   it.Id,
					Name: domain,
				}
				zones = append(zones, zone)
			}
		}
	}
	return zones, nil
}

// GetRecord -
func GetRecord(id *string, names []string) ([]*route53.ResourceRecordSet, error) {
	if id == nil {
		return nil, errors.New("no id input")
	}
	if len(names) == 0 {
		return nil, errors.New("no record names")
	}
	records := make([]string, 0)
	for _, v := range names {
		if len(v) > 0 {
			records = append(records, v)
		}
	}

	input := &route53.ListResourceRecordSetsInput{}
	input.SetHostedZoneId(*id)
	resOut, err := client.R53.ListResourceRecordSets(input)
	if err != nil {
		return nil, err
	}
	if len(resOut.ResourceRecordSets) == 0 {
		return nil, errors.New("no record sets")
	}

	sets := make([]*route53.ResourceRecordSet, 0)
	for _, it := range resOut.ResourceRecordSets {
		for _, name := range records {
			if *it.Name == name {
				sets = append(sets, it)
			}
		}
	}

	return sets, nil
}

// UpdateRecord -
func UpdateRecord(zoneID *string, sets []*route53.ResourceRecordSet) error {
	if len(sets) == 0 {
		return errors.New("no change set input")
	}
	changeSets := make([]*route53.Change, 0)

	for _, v := range sets {
		changeSets = append(changeSets, &route53.Change{
			ResourceRecordSet: v,
			Action:            aws.String("UPSERT"),
		})
	}

	changeInput := &route53.ChangeResourceRecordSetsInput{
		HostedZoneId: zoneID,
		ChangeBatch: &route53.ChangeBatch{
			Changes: changeSets,
		},
	}
	_, err := client.R53.ChangeResourceRecordSets(changeInput)
	if err != nil {
		return err
	}

	return nil
}