package dns

import (
	"net"
	"strings"

	dnsModel "dove/models/dns"
	domainModel "dove/models/domain"
	dnsRepo "dove/repositories/dns"
	domainRepo "dove/repositories/domain"
	"dove/utils/shortcuts"
)

type RecordEntry struct {
	ID       uint   `json:"id"`
	Type     string `json:"type"`
	Name     string `json:"name"`
	Value    string `json:"value"`
	TTL      uint32 `json:"ttl"`
	Priority uint16 `json:"priority"`
}

type DomainRecordsResponse struct {
	Domain  domainModel.Domain `json:"domain"`
	Records []RecordEntry      `json:"records"`
}

type UpdateRecordRequest struct {
	Name     string `form:"name"`
	Value    string `form:"value"`
	TTL      uint32 `form:"ttl"`
	Priority uint16 `form:"priority"`
}

type CreateRecordRequest struct {
	DomainID   uint   `form:"domain_id"`
	RecordType string `form:"record_type"`
	Name       string `form:"name"`
	Value      string `form:"value"`
	TTL        uint32 `form:"ttl"`
	Priority   uint16 `form:"priority"`
	Weight     uint16 `form:"weight"`
	Port       uint16 `form:"port"`
	Protocol   string `form:"protocol"`
}

func DomainRecords(domainID uint) (*DomainRecordsResponse, *shortcuts.Error) {
	foundDomain := domainRepo.FindDomainByID(domainID)
	if foundDomain == nil {
		return nil, shortcuts.ServiceError(shortcuts.NotFound, DomainNotFound)
	}

	records := collectAllRecords(domainID)

	return &DomainRecordsResponse{
		Domain:  *foundDomain,
		Records: records,
	}, nil
}

func CreateRecord(request CreateRecordRequest) *shortcuts.Error {
	foundDomain := domainRepo.FindDomainByID(request.DomainID)
	if foundDomain == nil {
		return shortcuts.ServiceError(shortcuts.NotFound, DomainNotFound)
	}

	name := strings.TrimSpace(request.Name)
	value := strings.TrimSpace(request.Value)
	ttl := request.TTL
	if ttl == 0 {
		ttl = 1
	}

	switch request.RecordType {
	case "A":
		return createARecord(request.DomainID, name, value, ttl)
	case "AAAA":
		return createAAAARecord(request.DomainID, name, value, ttl)
	case "CNAME":
		return createCNAMERecord(request.DomainID, name, value, ttl)
	case "MX":
		return createMXRecord(request.DomainID, name, value, ttl, request.Priority)
	case "TXT":
		return createTXTRecord(request.DomainID, name, value, ttl)
	case "SRV":
		return createSRVRecord(request.DomainID, name, value, ttl, request.Priority, request.Weight, request.Port, request.Protocol)
	default:
		return shortcuts.ServiceError(shortcuts.BadRequest, TypeInvalid)
	}
}

func UpdateRecord(recordType string, recordID uint, request UpdateRecordRequest) *shortcuts.Error {
	name := strings.TrimSpace(request.Name)
	value := strings.TrimSpace(request.Value)
	ttl := request.TTL
	if ttl == 0 {
		ttl = 1
	}

	switch recordType {
	case "A":
		record := dnsRepo.FindARecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if name != "" {
			record.Name = name
		}
		if value != "" {
			record.Address = value
		}
		record.TTL = ttl
		if updateError := dnsRepo.UpdateARecord(record); updateError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordUpdateFailed)
		}

	case "AAAA":
		record := dnsRepo.FindAAAARecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if name != "" {
			record.Name = name
		}
		if value != "" {
			record.Address = value
		}
		record.TTL = ttl
		if updateError := dnsRepo.UpdateAAAARecord(record); updateError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordUpdateFailed)
		}

	case "CNAME":
		record := dnsRepo.FindCNAMERecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if name != "" {
			record.Name = name
		}
		if value != "" {
			record.Target = value
		}
		record.TTL = ttl
		if updateError := dnsRepo.UpdateCNAMERecord(record); updateError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordUpdateFailed)
		}

	case "MX":
		record := dnsRepo.FindMXRecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if name != "" {
			record.Name = name
		}
		if value != "" {
			record.Target = value
		}
		if request.Priority > 0 {
			record.Priority = request.Priority
		}
		record.TTL = ttl
		if updateError := dnsRepo.UpdateMXRecord(record); updateError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordUpdateFailed)
		}

	case "TXT":
		record := dnsRepo.FindTXTRecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if name != "" {
			record.Name = name
		}
		if value != "" {
			record.Content = value
		}
		record.TTL = ttl
		if updateError := dnsRepo.UpdateTXTRecord(record); updateError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordUpdateFailed)
		}

	case "SRV":
		record := dnsRepo.FindSRVRecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if name != "" {
			record.Name = name
		}
		if value != "" {
			record.Target = value
		}
		if request.Priority > 0 {
			record.Priority = request.Priority
		}
		record.TTL = ttl
		if updateError := dnsRepo.UpdateSRVRecord(record); updateError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordUpdateFailed)
		}

	default:
		return shortcuts.ServiceError(shortcuts.BadRequest, TypeInvalid)
	}

	return nil
}

func DeleteRecord(recordType string, recordID uint) *shortcuts.Error {
	switch recordType {
	case "A":
		record := dnsRepo.FindARecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if deleteError := dnsRepo.DeleteARecord(record); deleteError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordDeletionFailed)
		}

	case "AAAA":
		record := dnsRepo.FindAAAARecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if deleteError := dnsRepo.DeleteAAAARecord(record); deleteError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordDeletionFailed)
		}

	case "CNAME":
		record := dnsRepo.FindCNAMERecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if deleteError := dnsRepo.DeleteCNAMERecord(record); deleteError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordDeletionFailed)
		}

	case "MX":
		record := dnsRepo.FindMXRecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if deleteError := dnsRepo.DeleteMXRecord(record); deleteError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordDeletionFailed)
		}

	case "TXT":
		record := dnsRepo.FindTXTRecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if deleteError := dnsRepo.DeleteTXTRecord(record); deleteError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordDeletionFailed)
		}

	case "SRV":
		record := dnsRepo.FindSRVRecordByID(recordID)
		if record == nil {
			return shortcuts.ServiceError(shortcuts.NotFound, RecordNotFound)
		}
		if deleteError := dnsRepo.DeleteSRVRecord(record); deleteError != nil {
			return shortcuts.ServiceError(shortcuts.Internal, RecordDeletionFailed)
		}

	default:
		return shortcuts.ServiceError(shortcuts.BadRequest, TypeInvalid)
	}

	return nil
}

func collectAllRecords(domainID uint) []RecordEntry {
	var entries []RecordEntry

	for _, record := range dnsRepo.FindARecordsByDomainID(domainID) {
		entries = append(entries, RecordEntry{
			ID:    record.ID,
			Type:  "A",
			Name:  record.Name,
			Value: record.Address,
			TTL:   record.TTL,
		})
	}

	for _, record := range dnsRepo.FindAAAARecordsByDomainID(domainID) {
		entries = append(entries, RecordEntry{
			ID:    record.ID,
			Type:  "AAAA",
			Name:  record.Name,
			Value: record.Address,
			TTL:   record.TTL,
		})
	}

	for _, record := range dnsRepo.FindCNAMERecordsByDomainID(domainID) {
		entries = append(entries, RecordEntry{
			ID:    record.ID,
			Type:  "CNAME",
			Name:  record.Name,
			Value: record.Target,
			TTL:   record.TTL,
		})
	}

	for _, record := range dnsRepo.FindMXRecordsByDomainID(domainID) {
		entries = append(entries, RecordEntry{
			ID:       record.ID,
			Type:     "MX",
			Name:     record.Name,
			Value:    record.Target,
			TTL:      record.TTL,
			Priority: record.Priority,
		})
	}

	for _, record := range dnsRepo.FindTXTRecordsByDomainID(domainID) {
		entries = append(entries, RecordEntry{
			ID:    record.ID,
			Type:  "TXT",
			Name:  record.Name,
			Value: record.Content,
			TTL:   record.TTL,
		})
	}

	for _, record := range dnsRepo.FindSRVRecordsByDomainID(domainID) {
		entries = append(entries, RecordEntry{
			ID:       record.ID,
			Type:     "SRV",
			Name:     record.Name,
			Value:    record.Target,
			TTL:      record.TTL,
			Priority: record.Priority,
		})
	}

	return entries
}

func createARecord(domainID uint, name string, address string, ttl uint32) *shortcuts.Error {
	if address == "" {
		return shortcuts.ServiceError(shortcuts.BadRequest, AddressRequired)
	}

	parsedIP := net.ParseIP(address)
	if parsedIP == nil || parsedIP.To4() == nil {
		return shortcuts.ServiceError(shortcuts.BadRequest, AddressInvalid)
	}

	if name == "" {
		name = "@"
	}

	record := &dnsModel.ARecord{
		DomainID: domainID,
		Name:     name,
		Address:  address,
		TTL:      ttl,
	}

	if createError := dnsRepo.CreateARecord(record); createError != nil {
		return shortcuts.ServiceError(shortcuts.Internal, RecordCreationFailed)
	}

	return nil
}

func createAAAARecord(domainID uint, name string, address string, ttl uint32) *shortcuts.Error {
	if address == "" {
		return shortcuts.ServiceError(shortcuts.BadRequest, AddressRequired)
	}

	parsedIP := net.ParseIP(address)
	if parsedIP == nil || parsedIP.To16() == nil || parsedIP.To4() != nil {
		return shortcuts.ServiceError(shortcuts.BadRequest, AddressIPv6Invalid)
	}

	if name == "" {
		name = "@"
	}

	record := &dnsModel.AAAARecord{
		DomainID: domainID,
		Name:     name,
		Address:  address,
		TTL:      ttl,
	}

	if createError := dnsRepo.CreateAAAARecord(record); createError != nil {
		return shortcuts.ServiceError(shortcuts.Internal, RecordCreationFailed)
	}

	return nil
}

func createCNAMERecord(domainID uint, name string, target string, ttl uint32) *shortcuts.Error {
	if name == "" {
		return shortcuts.ServiceError(shortcuts.BadRequest, NameRequired)
	}

	if target == "" {
		return shortcuts.ServiceError(shortcuts.BadRequest, TargetRequired)
	}

	record := &dnsModel.CNAMERecord{
		DomainID: domainID,
		Name:     name,
		Target:   target,
		TTL:      ttl,
	}

	if createError := dnsRepo.CreateCNAMERecord(record); createError != nil {
		return shortcuts.ServiceError(shortcuts.Internal, RecordCreationFailed)
	}

	return nil
}

func createMXRecord(domainID uint, name string, target string, ttl uint32, priority uint16) *shortcuts.Error {
	if target == "" {
		return shortcuts.ServiceError(shortcuts.BadRequest, TargetRequired)
	}

	if name == "" {
		name = "@"
	}

	if priority == 0 {
		priority = 10
	}

	record := &dnsModel.MXRecord{
		DomainID: domainID,
		Name:     name,
		Target:   target,
		Priority: priority,
		TTL:      ttl,
	}

	if createError := dnsRepo.CreateMXRecord(record); createError != nil {
		return shortcuts.ServiceError(shortcuts.Internal, RecordCreationFailed)
	}

	return nil
}

func createTXTRecord(domainID uint, name string, content string, ttl uint32) *shortcuts.Error {
	if content == "" {
		return shortcuts.ServiceError(shortcuts.BadRequest, ContentRequired)
	}

	if name == "" {
		name = "@"
	}

	record := &dnsModel.TXTRecord{
		DomainID: domainID,
		Name:     name,
		Content:  content,
		TTL:      ttl,
	}

	if createError := dnsRepo.CreateTXTRecord(record); createError != nil {
		return shortcuts.ServiceError(shortcuts.Internal, RecordCreationFailed)
	}

	return nil
}

func createSRVRecord(domainID uint, name string, target string, ttl uint32, priority uint16, weight uint16, port uint16, protocol string) *shortcuts.Error {
	if name == "" {
		return shortcuts.ServiceError(shortcuts.BadRequest, NameRequired)
	}

	if target == "" {
		return shortcuts.ServiceError(shortcuts.BadRequest, TargetRequired)
	}

	if port == 0 {
		return shortcuts.ServiceError(shortcuts.BadRequest, PortRequired)
	}

	if protocol == "" {
		protocol = "tcp"
	}

	record := &dnsModel.SRVRecord{
		DomainID: domainID,
		Name:     name,
		Target:   target,
		Priority: priority,
		Weight:   weight,
		Port:     port,
		Protocol: protocol,
		TTL:      ttl,
	}

	if createError := dnsRepo.CreateSRVRecord(record); createError != nil {
		return shortcuts.ServiceError(shortcuts.Internal, RecordCreationFailed)
	}

	return nil
}