package sub

import (
	"encoding/base64"
	"fmt"
	"maps"
	"net"
	"net/url"
	"slices"
	"strings"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/goccy/go-json"

	"github.com/mhsanaei/3x-ui/v3/database"
	"github.com/mhsanaei/3x-ui/v3/database/model"
	"github.com/mhsanaei/3x-ui/v3/logger"
	"github.com/mhsanaei/3x-ui/v3/util/common"
	"github.com/mhsanaei/3x-ui/v3/util/random"
	"github.com/mhsanaei/3x-ui/v3/web/service"
	"github.com/mhsanaei/3x-ui/v3/xray"
)

// SubService provides business logic for generating subscription links and managing subscription data.
type SubService struct {
	address        string
	showInfo       bool
	remarkModel    string
	datepicker     string
	inboundService service.InboundService
	settingService service.SettingService
	// nodesByID is populated per request from the Node table so
	// resolveInboundAddress can return the node's address for any
	// inbound whose NodeID is set. Keeps the per-link host derivation
	// O(1) instead of O(N) DB hits.
	nodesByID map[int]*model.Node
}

// NewSubService creates a new subscription service with the given configuration.
func NewSubService(showInfo bool, remarkModel string) *SubService {
	return &SubService{
		showInfo:    showInfo,
		remarkModel: remarkModel,
	}
}

// PrepareForRequest sets per-request state (host + nodes map) on the
// shared SubService. Called by every entry point — GetSubs, GetJson,
// GetClash — so resolveInboundAddress sees the right host and the
// freshly-loaded node map regardless of which sub flavour the client
// hit.
func (s *SubService) PrepareForRequest(host string) {
	s.address = host
	s.loadNodes()
}

// GetSubs retrieves subscription links for a given subscription ID and host.
func (s *SubService) GetSubs(subId string, host string) ([]string, int64, xray.ClientTraffic, error) {
	s.PrepareForRequest(host)
	var result []string
	var traffic xray.ClientTraffic
	var lastOnline int64
	var hasEnabledClient bool
	var clientTraffics []xray.ClientTraffic
	inbounds, err := s.getInboundsBySubId(subId)
	if err != nil {
		return nil, 0, traffic, err
	}

	if len(inbounds) == 0 {
		return nil, 0, traffic, common.NewError("No inbounds found with ", subId)
	}

	s.datepicker, err = s.settingService.GetDatepicker()
	if err != nil {
		s.datepicker = "gregorian"
	}
	seenEmails := make(map[string]struct{})
	for _, inbound := range inbounds {
		clients, err := s.inboundService.GetClients(inbound)
		if err != nil {
			logger.Error("SubService - GetClients: Unable to get clients from inbound")
		}
		if clients == nil {
			continue
		}
		if len(inbound.Listen) > 0 && inbound.Listen[0] == '@' {
			listen, port, streamSettings, err := s.getFallbackMaster(inbound.Listen, inbound.StreamSettings)
			if err == nil {
				inbound.Listen = listen
				inbound.Port = port
				inbound.StreamSettings = streamSettings
			}
		}
		for _, client := range clients {
			if client.SubID == subId {
				if client.Enable {
					hasEnabledClient = true
				}
				result = append(result, s.getLink(inbound, client.Email))
				var ct xray.ClientTraffic
				ct, clientTraffics = s.appendUniqueTraffic(seenEmails, clientTraffics, inbound.ClientStats, client.Email)
				if ct.LastOnline > lastOnline {
					lastOnline = ct.LastOnline
				}
			}
		}
	}

	// Prepare statistics
	for index, clientTraffic := range clientTraffics {
		if index == 0 {
			traffic.Up = clientTraffic.Up
			traffic.Down = clientTraffic.Down
			traffic.Total = clientTraffic.Total
			if clientTraffic.ExpiryTime > 0 {
				traffic.ExpiryTime = clientTraffic.ExpiryTime
			}
		} else {
			traffic.Up += clientTraffic.Up
			traffic.Down += clientTraffic.Down
			if traffic.Total == 0 || clientTraffic.Total == 0 {
				traffic.Total = 0
			} else {
				traffic.Total += clientTraffic.Total
			}
			if clientTraffic.ExpiryTime != traffic.ExpiryTime {
				traffic.ExpiryTime = 0
			}
		}
	}
	traffic.Enable = hasEnabledClient
	return result, lastOnline, traffic, nil
}

func (s *SubService) getInboundsBySubId(subId string) ([]*model.Inbound, error) {
	db := database.GetDB()
	var inbounds []*model.Inbound
	// allow "hysteria2" so imports stored with the literal v2 protocol
	// string still surface here (#4081)
	err := db.Model(model.Inbound{}).Preload("ClientStats").Where(`id in (
		SELECT DISTINCT inbounds.id
		FROM inbounds,
			JSON_EACH(JSON_EXTRACT(inbounds.settings, '$.clients')) AS client
		WHERE
			protocol in ('vmess','vless','trojan','shadowsocks','hysteria','hysteria2')
			AND JSON_EXTRACT(client.value, '$.subId') = ? AND enable = ?
	)`, subId, true).Find(&inbounds).Error
	if err != nil {
		return nil, err
	}
	return inbounds, nil
}

// appendUniqueTraffic resolves the traffic stats for email and appends them
// to acc only the first time email is seen. Shared-email mode lets one
// client_traffics row underpin several inbounds, so without dedupe its
// quota and usage would be counted once per inbound.
func (s *SubService) appendUniqueTraffic(seen map[string]struct{}, acc []xray.ClientTraffic, stats []xray.ClientTraffic, email string) (xray.ClientTraffic, []xray.ClientTraffic) {
	ct := s.getClientTraffics(stats, email)
	if _, dup := seen[email]; !dup {
		seen[email] = struct{}{}
		acc = append(acc, ct)
	}
	return ct, acc
}

func (s *SubService) getClientTraffics(traffics []xray.ClientTraffic, email string) xray.ClientTraffic {
	for _, traffic := range traffics {
		if traffic.Email == email {
			return traffic
		}
	}
	return xray.ClientTraffic{}
}

func (s *SubService) getFallbackMaster(dest string, streamSettings string) (string, int, string, error) {
	db := database.GetDB()
	var inbound *model.Inbound
	err := db.Model(model.Inbound{}).
		Where("JSON_TYPE(settings, '$.fallbacks') = 'array'").
		Where("EXISTS (SELECT * FROM json_each(settings, '$.fallbacks') WHERE json_extract(value, '$.dest') = ?)", dest).
		Find(&inbound).Error
	if err != nil {
		return "", 0, "", err
	}

	var stream map[string]any
	json.Unmarshal([]byte(streamSettings), &stream)
	var masterStream map[string]any
	json.Unmarshal([]byte(inbound.StreamSettings), &masterStream)
	stream["security"] = masterStream["security"]
	stream["tlsSettings"] = masterStream["tlsSettings"]
	stream["externalProxy"] = masterStream["externalProxy"]
	modifiedStream, _ := json.MarshalIndent(stream, "", "  ")

	return inbound.Listen, inbound.Port, string(modifiedStream), nil
}

func (s *SubService) getLink(inbound *model.Inbound, email string) string {
	switch inbound.Protocol {
	case "vmess":
		return s.genVmessLink(inbound, email)
	case "vless":
		return s.genVlessLink(inbound, email)
	case "trojan":
		return s.genTrojanLink(inbound, email)
	case "shadowsocks":
		return s.genShadowsocksLink(inbound, email)
	case "hysteria", "hysteria2":
		return s.genHysteriaLink(inbound, email)
	}
	return ""
}

// Protocol link generators are intentionally ordered as:
// vmess -> vless -> trojan -> shadowsocks -> hysteria.
func (s *SubService) genVmessLink(inbound *model.Inbound, email string) string {
	if inbound.Protocol != model.VMESS {
		return ""
	}
	address := s.resolveInboundAddress(inbound)
	obj := map[string]any{
		"v":    "2",
		"add":  address,
		"port": inbound.Port,
		"type": "none",
	}
	stream := unmarshalStreamSettings(inbound.StreamSettings)
	network, _ := stream["network"].(string)
	applyVmessNetworkParams(stream, network, obj)
	if finalmask, ok := stream["finalmask"].(map[string]any); ok {
		applyFinalMaskObj(finalmask, obj)
	}
	security, _ := stream["security"].(string)
	obj["tls"] = security
	if security == "tls" {
		applyVmessTLSParams(stream, obj)
	}

	clients, _ := s.inboundService.GetClients(inbound)
	clientIndex := findClientIndex(clients, email)
	obj["id"] = clients[clientIndex].ID
	obj["scy"] = clients[clientIndex].Security

	externalProxies, _ := stream["externalProxy"].([]any)

	if len(externalProxies) > 0 {
		return s.buildVmessExternalProxyLinks(externalProxies, obj, inbound, email)
	}

	obj["ps"] = s.genRemark(inbound, email, "")
	return buildVmessLink(obj)
}

func (s *SubService) genVlessLink(inbound *model.Inbound, email string) string {
	if inbound.Protocol != model.VLESS {
		return ""
	}
	address := s.resolveInboundAddress(inbound)
	stream := unmarshalStreamSettings(inbound.StreamSettings)
	clients, _ := s.inboundService.GetClients(inbound)
	clientIndex := findClientIndex(clients, email)
	uuid := clients[clientIndex].ID
	port := inbound.Port
	streamNetwork := stream["network"].(string)
	params := make(map[string]string)
	params["type"] = streamNetwork

	// Add encryption parameter for VLESS from inbound settings
	var settings map[string]any
	json.Unmarshal([]byte(inbound.Settings), &settings)
	if encryption, ok := settings["encryption"].(string); ok {
		params["encryption"] = encryption
	}

	applyShareNetworkParams(stream, streamNetwork, params)
	if finalmask, ok := stream["finalmask"].(map[string]any); ok {
		applyFinalMaskParams(finalmask, params)
	}
	security, _ := stream["security"].(string)
	switch security {
	case "tls":
		applyShareTLSParams(stream, params)
		if streamNetwork == "tcp" && len(clients[clientIndex].Flow) > 0 {
			params["flow"] = clients[clientIndex].Flow
		}
	case "reality":
		applyShareRealityParams(stream, params)
		if streamNetwork == "tcp" && len(clients[clientIndex].Flow) > 0 {
			params["flow"] = clients[clientIndex].Flow
		}
	default:
		params["security"] = "none"
	}

	externalProxies, _ := stream["externalProxy"].([]any)

	if len(externalProxies) > 0 {
		return s.buildExternalProxyURLLinks(
			externalProxies,
			params,
			security,
			func(dest string, port int) string {
				return fmt.Sprintf("vless://%s@%s:%d", uuid, dest, port)
			},
			func(ep map[string]any) string {
				return s.genRemark(inbound, email, ep["remark"].(string))
			},
		)
	}

	link := fmt.Sprintf("vless://%s@%s:%d", uuid, address, port)
	return buildLinkWithParams(link, params, s.genRemark(inbound, email, ""))
}

func (s *SubService) genTrojanLink(inbound *model.Inbound, email string) string {
	if inbound.Protocol != model.Trojan {
		return ""
	}
	address := s.resolveInboundAddress(inbound)
	stream := unmarshalStreamSettings(inbound.StreamSettings)
	clients, _ := s.inboundService.GetClients(inbound)
	clientIndex := findClientIndex(clients, email)
	password := clients[clientIndex].Password
	port := inbound.Port
	streamNetwork := stream["network"].(string)
	params := make(map[string]string)
	params["type"] = streamNetwork

	applyShareNetworkParams(stream, streamNetwork, params)
	if finalmask, ok := stream["finalmask"].(map[string]any); ok {
		applyFinalMaskParams(finalmask, params)
	}
	security, _ := stream["security"].(string)
	switch security {
	case "tls":
		applyShareTLSParams(stream, params)
	case "reality":
		applyShareRealityParams(stream, params)
		if streamNetwork == "tcp" && len(clients[clientIndex].Flow) > 0 {
			params["flow"] = clients[clientIndex].Flow
		}
	default:
		params["security"] = "none"
	}

	externalProxies, _ := stream["externalProxy"].([]any)

	if len(externalProxies) > 0 {
		return s.buildExternalProxyURLLinks(
			externalProxies,
			params,
			security,
			func(dest string, port int) string {
				return fmt.Sprintf("trojan://%s@%s:%d", password, dest, port)
			},
			func(ep map[string]any) string {
				return s.genRemark(inbound, email, ep["remark"].(string))
			},
		)
	}

	link := fmt.Sprintf("trojan://%s@%s:%d", password, address, port)
	return buildLinkWithParams(link, params, s.genRemark(inbound, email, ""))
}

func (s *SubService) genShadowsocksLink(inbound *model.Inbound, email string) string {
	if inbound.Protocol != model.Shadowsocks {
		return ""
	}
	address := s.resolveInboundAddress(inbound)
	stream := unmarshalStreamSettings(inbound.StreamSettings)
	clients, _ := s.inboundService.GetClients(inbound)

	var settings map[string]any
	json.Unmarshal([]byte(inbound.Settings), &settings)
	inboundPassword := settings["password"].(string)
	method := settings["method"].(string)
	clientIndex := findClientIndex(clients, email)
	streamNetwork := stream["network"].(string)
	params := make(map[string]string)
	params["type"] = streamNetwork

	applyShareNetworkParams(stream, streamNetwork, params)
	if finalmask, ok := stream["finalmask"].(map[string]any); ok {
		applyFinalMaskParams(finalmask, params)
	}

	security, _ := stream["security"].(string)
	if security == "tls" {
		applyShareTLSParams(stream, params)
	}

	encPart := fmt.Sprintf("%s:%s", method, clients[clientIndex].Password)
	if method[0] == '2' {
		encPart = fmt.Sprintf("%s:%s:%s", method, inboundPassword, clients[clientIndex].Password)
	}

	externalProxies, _ := stream["externalProxy"].([]any)

	if len(externalProxies) > 0 {
		proxyParams := cloneStringMap(params)
		proxyParams["security"] = security
		return s.buildExternalProxyURLLinks(
			externalProxies,
			proxyParams,
			security,
			func(dest string, port int) string {
				return fmt.Sprintf("ss://%s@%s:%d", base64.StdEncoding.EncodeToString([]byte(encPart)), dest, port)
			},
			func(ep map[string]any) string {
				return s.genRemark(inbound, email, ep["remark"].(string))
			},
		)
	}

	link := fmt.Sprintf("ss://%s@%s:%d", base64.StdEncoding.EncodeToString([]byte(encPart)), address, inbound.Port)
	return buildLinkWithParams(link, params, s.genRemark(inbound, email, ""))
}

func (s *SubService) genHysteriaLink(inbound *model.Inbound, email string) string {
	if !model.IsHysteria(inbound.Protocol) {
		return ""
	}
	var stream map[string]any
	json.Unmarshal([]byte(inbound.StreamSettings), &stream)
	clients, _ := s.inboundService.GetClients(inbound)
	clientIndex := -1
	for i, client := range clients {
		if client.Email == email {
			clientIndex = i
			break
		}
	}
	auth := clients[clientIndex].Auth
	params := make(map[string]string)

	params["security"] = "tls"
	tlsSetting, _ := stream["tlsSettings"].(map[string]any)
	alpns, _ := tlsSetting["alpn"].([]any)
	var alpn []string
	for _, a := range alpns {
		alpn = append(alpn, a.(string))
	}
	if len(alpn) > 0 {
		params["alpn"] = strings.Join(alpn, ",")
	}
	if sniValue, ok := searchKey(tlsSetting, "serverName"); ok {
		params["sni"], _ = sniValue.(string)
	}

	tlsSettings, _ := searchKey(tlsSetting, "settings")
	if tlsSetting != nil {
		if fpValue, ok := searchKey(tlsSettings, "fingerprint"); ok {
			params["fp"], _ = fpValue.(string)
		}
		if insecure, ok := searchKey(tlsSettings, "allowInsecure"); ok {
			if insecure.(bool) {
				params["insecure"] = "1"
			}
		}
	}

	// salamander obfs (Hysteria2). The panel-side link generator already
	// emits these; keep the subscription output in sync so a client has
	// the obfs password to match the server.
	if finalmask, ok := stream["finalmask"].(map[string]any); ok {
		applyFinalMaskParams(finalmask, params)
		if udpMasks, ok := finalmask["udp"].([]any); ok {
			for _, m := range udpMasks {
				mask, _ := m.(map[string]any)
				if mask == nil || mask["type"] != "salamander" {
					continue
				}
				settings, _ := mask["settings"].(map[string]any)
				if pw, ok := settings["password"].(string); ok && pw != "" {
					params["obfs"] = "salamander"
					params["obfs-password"] = pw
					break
				}
			}
		}
	}

	var settings map[string]any
	json.Unmarshal([]byte(inbound.Settings), &settings)
	version, _ := settings["version"].(float64)
	protocol := "hysteria2"
	if int(version) == 1 {
		protocol = "hysteria"
	}

	// Fan out one link per External Proxy entry if any. Previously this
	// generator ignored `externalProxy` entirely, so the link kept the
	// server's own IP/port even when the admin configured an alternate
	// endpoint (e.g. a CDN hostname + port that forwards to the node).
	// Matches the behaviour of genVlessLink / genTrojanLink / ….
	externalProxies, _ := stream["externalProxy"].([]any)
	if len(externalProxies) > 0 {
		links := make([]string, 0, len(externalProxies))
		for _, externalProxy := range externalProxies {
			ep, ok := externalProxy.(map[string]any)
			if !ok {
				continue
			}
			dest, _ := ep["dest"].(string)
			portF, okPort := ep["port"].(float64)
			if dest == "" || !okPort {
				continue
			}
			epRemark, _ := ep["remark"].(string)

			link := fmt.Sprintf("%s://%s@%s:%d", protocol, auth, dest, int(portF))
			u, _ := url.Parse(link)
			q := u.Query()
			for k, v := range params {
				q.Add(k, v)
			}
			u.RawQuery = q.Encode()
			u.Fragment = s.genRemark(inbound, email, epRemark)
			links = append(links, u.String())
		}
		return strings.Join(links, "\n")
	}

	// No external proxy configured — fall back to the request host.
	link := fmt.Sprintf("%s://%s@%s:%d", protocol, auth, s.address, inbound.Port)
	url, _ := url.Parse(link)
	q := url.Query()
	for k, v := range params {
		q.Add(k, v)
	}
	url.RawQuery = q.Encode()
	url.Fragment = s.genRemark(inbound, email, "")
	return url.String()
}

// loadNodes refreshes nodesByID from the DB. Called once per request so
// the per-inbound resolveInboundAddress lookups are pure map reads.
// We filter to address != ” so a half-configured node row doesn't
// accidentally produce a useless host like "https://:2053".
func (s *SubService) loadNodes() {
	db := database.GetDB()
	var nodes []*model.Node
	if err := db.Model(&model.Node{}).Where("address != ''").Find(&nodes).Error; err != nil {
		logger.Warning("subscription: load nodes failed:", err)
		s.nodesByID = nil
		return
	}
	m := make(map[int]*model.Node, len(nodes))
	for _, n := range nodes {
		m[n.Id] = n
	}
	s.nodesByID = m
}

// resolveInboundAddress picks the host an external client should
// connect to. Order:
//  1. If the inbound is node-managed and the node has an address, use
//     the node's address — central panel's hostname doesn't speak xray
//     for that inbound.
//  2. If the inbound binds to a non-wildcard listen address, use it.
//  3. Otherwise fall back to the request's host (whatever the client
//     subscribed against).
func (s *SubService) resolveInboundAddress(inbound *model.Inbound) string {
	if inbound.NodeID != nil && s.nodesByID != nil {
		if n, ok := s.nodesByID[*inbound.NodeID]; ok && n.Address != "" {
			return n.Address
		}
	}
	if inbound.Listen == "" || inbound.Listen == "0.0.0.0" || inbound.Listen == "::" || inbound.Listen == "::0" {
		return s.address
	}
	return inbound.Listen
}

func findClientIndex(clients []model.Client, email string) int {
	for i, client := range clients {
		if client.Email == email {
			return i
		}
	}
	return -1
}

func unmarshalStreamSettings(streamSettings string) map[string]any {
	var stream map[string]any
	json.Unmarshal([]byte(streamSettings), &stream)
	return stream
}

func applyPathAndHostParams(settings map[string]any, params map[string]string) {
	params["path"] = settings["path"].(string)
	if host, ok := settings["host"].(string); ok && len(host) > 0 {
		params["host"] = host
	} else {
		headers, _ := settings["headers"].(map[string]any)
		params["host"] = searchHost(headers)
	}
}

func applyPathAndHostObj(settings map[string]any, obj map[string]any) {
	obj["path"] = settings["path"].(string)
	if host, ok := settings["host"].(string); ok && len(host) > 0 {
		obj["host"] = host
	} else {
		headers, _ := settings["headers"].(map[string]any)
		obj["host"] = searchHost(headers)
	}
}

func applyShareNetworkParams(stream map[string]any, streamNetwork string, params map[string]string) {
	switch streamNetwork {
	case "tcp":
		tcp, _ := stream["tcpSettings"].(map[string]any)
		header, _ := tcp["header"].(map[string]any)
		typeStr, _ := header["type"].(string)
		if typeStr == "http" {
			request := header["request"].(map[string]any)
			requestPath, _ := request["path"].([]any)
			params["path"] = requestPath[0].(string)
			headers, _ := request["headers"].(map[string]any)
			params["host"] = searchHost(headers)
			params["headerType"] = "http"
		}
	case "kcp":
		applyKcpShareParams(stream, params)
	case "ws":
		ws, _ := stream["wsSettings"].(map[string]any)
		applyPathAndHostParams(ws, params)
	case "grpc":
		grpc, _ := stream["grpcSettings"].(map[string]any)
		params["serviceName"] = grpc["serviceName"].(string)
		params["authority"], _ = grpc["authority"].(string)
		if grpc["multiMode"].(bool) {
			params["mode"] = "multi"
		}
	case "httpupgrade":
		httpupgrade, _ := stream["httpupgradeSettings"].(map[string]any)
		applyPathAndHostParams(httpupgrade, params)
	case "xhttp":
		xhttp, _ := stream["xhttpSettings"].(map[string]any)
		applyXhttpExtraParams(xhttp, params)
	}
}

// applyXhttpExtraObj copies the bidirectional xhttp settings into the
// VMess base64 JSON link object. VMess supports arbitrary keys, so we
// flatten the SplitHTTPConfig "extra" fields directly onto obj.
func applyXhttpExtraObj(xhttp map[string]any, obj map[string]any) {
	if xpb, ok := xhttp["xPaddingBytes"].(string); ok && len(xpb) > 0 {
		obj["x_padding_bytes"] = xpb
	}
	maps.Copy(obj, buildXhttpExtra(xhttp))
}

func applyVmessNetworkParams(stream map[string]any, network string, obj map[string]any) {
	obj["net"] = network
	switch network {
	case "tcp":
		tcp, _ := stream["tcpSettings"].(map[string]any)
		header, _ := tcp["header"].(map[string]any)
		typeStr, _ := header["type"].(string)
		obj["type"] = typeStr
		if typeStr == "http" {
			request := header["request"].(map[string]any)
			requestPath, _ := request["path"].([]any)
			obj["path"] = requestPath[0].(string)
			headers, _ := request["headers"].(map[string]any)
			obj["host"] = searchHost(headers)
		}
	case "kcp":
		applyKcpShareObj(stream, obj)
	case "ws":
		ws, _ := stream["wsSettings"].(map[string]any)
		applyPathAndHostObj(ws, obj)
	case "grpc":
		grpc, _ := stream["grpcSettings"].(map[string]any)
		obj["path"] = grpc["serviceName"].(string)
		obj["authority"] = grpc["authority"].(string)
		if grpc["multiMode"].(bool) {
			obj["type"] = "multi"
		}
	case "httpupgrade":
		httpupgrade, _ := stream["httpupgradeSettings"].(map[string]any)
		applyPathAndHostObj(httpupgrade, obj)
	case "xhttp":
		xhttp, _ := stream["xhttpSettings"].(map[string]any)
		applyPathAndHostObj(xhttp, obj)
		if mode, ok := xhttp["mode"].(string); ok {
			obj["mode"] = mode
		}
		applyXhttpExtraObj(xhttp, obj)
	}
}

func applyShareTLSParams(stream map[string]any, params map[string]string) {
	params["security"] = "tls"
	tlsSetting, _ := stream["tlsSettings"].(map[string]any)
	alpns, _ := tlsSetting["alpn"].([]any)
	var alpn []string
	for _, a := range alpns {
		alpn = append(alpn, a.(string))
	}
	if len(alpn) > 0 {
		params["alpn"] = strings.Join(alpn, ",")
	}
	if sniValue, ok := searchKey(tlsSetting, "serverName"); ok {
		params["sni"], _ = sniValue.(string)
	}

	tlsSettings, _ := searchKey(tlsSetting, "settings")
	if tlsSetting != nil {
		if fpValue, ok := searchKey(tlsSettings, "fingerprint"); ok {
			params["fp"], _ = fpValue.(string)
		}
	}
}

func applyVmessTLSParams(stream map[string]any, obj map[string]any) {
	tlsSetting, _ := stream["tlsSettings"].(map[string]any)
	alpns, _ := tlsSetting["alpn"].([]any)
	if len(alpns) > 0 {
		var alpn []string
		for _, a := range alpns {
			alpn = append(alpn, a.(string))
		}
		obj["alpn"] = strings.Join(alpn, ",")
	}
	if sniValue, ok := searchKey(tlsSetting, "serverName"); ok {
		obj["sni"], _ = sniValue.(string)
	}

	tlsSettings, _ := searchKey(tlsSetting, "settings")
	if tlsSetting != nil {
		if fpValue, ok := searchKey(tlsSettings, "fingerprint"); ok {
			obj["fp"], _ = fpValue.(string)
		}
	}
}

func applyShareRealityParams(stream map[string]any, params map[string]string) {
	params["security"] = "reality"
	realitySetting, _ := stream["realitySettings"].(map[string]any)
	realitySettings, _ := searchKey(realitySetting, "settings")
	if realitySetting != nil {
		if sniValue, ok := searchKey(realitySetting, "serverNames"); ok {
			sNames, _ := sniValue.([]any)
			params["sni"] = sNames[random.Num(len(sNames))].(string)
		}
		if pbkValue, ok := searchKey(realitySettings, "publicKey"); ok {
			params["pbk"], _ = pbkValue.(string)
		}
		if sidValue, ok := searchKey(realitySetting, "shortIds"); ok {
			shortIds, _ := sidValue.([]any)
			params["sid"] = shortIds[random.Num(len(shortIds))].(string)
		}
		if fpValue, ok := searchKey(realitySettings, "fingerprint"); ok {
			if fp, ok := fpValue.(string); ok && len(fp) > 0 {
				params["fp"] = fp
			}
		}
		if pqvValue, ok := searchKey(realitySettings, "mldsa65Verify"); ok {
			if pqv, ok := pqvValue.(string); ok && len(pqv) > 0 {
				params["pqv"] = pqv
			}
		}
		params["spx"] = "/" + random.Seq(15)
	}
}

func buildVmessLink(obj map[string]any) string {
	jsonStr, _ := json.MarshalIndent(obj, "", "  ")
	return "vmess://" + base64.StdEncoding.EncodeToString(jsonStr)
}

func cloneVmessShareObj(baseObj map[string]any, newSecurity string) map[string]any {
	newObj := map[string]any{}
	for key, value := range baseObj {
		if !(newSecurity == "none" && (key == "alpn" || key == "sni" || key == "fp")) {
			newObj[key] = value
		}
	}
	return newObj
}

func (s *SubService) buildVmessExternalProxyLinks(externalProxies []any, baseObj map[string]any, inbound *model.Inbound, email string) string {
	var links strings.Builder
	for index, externalProxy := range externalProxies {
		ep, _ := externalProxy.(map[string]any)
		newSecurity, _ := ep["forceTls"].(string)
		newObj := cloneVmessShareObj(baseObj, newSecurity)
		newObj["ps"] = s.genRemark(inbound, email, ep["remark"].(string))
		newObj["add"] = ep["dest"].(string)
		newObj["port"] = int(ep["port"].(float64))

		if newSecurity != "same" {
			newObj["tls"] = newSecurity
		}
		if index > 0 {
			links.WriteString("\n")
		}
		links.WriteString(buildVmessLink(newObj))
	}
	return links.String()
}

func buildLinkWithParams(link string, params map[string]string, fragment string) string {
	parsedURL, _ := url.Parse(link)
	q := parsedURL.Query()
	for k, v := range params {
		q.Add(k, v)
	}
	parsedURL.RawQuery = q.Encode()
	parsedURL.Fragment = fragment
	return parsedURL.String()
}

func buildLinkWithParamsAndSecurity(link string, params map[string]string, fragment, security string, omitTLSFields bool) string {
	parsedURL, _ := url.Parse(link)
	q := parsedURL.Query()
	for k, v := range params {
		if k == "security" {
			v = security
		}
		if omitTLSFields && (k == "alpn" || k == "sni" || k == "fp") {
			continue
		}
		q.Add(k, v)
	}
	parsedURL.RawQuery = q.Encode()
	parsedURL.Fragment = fragment
	return parsedURL.String()
}

func (s *SubService) buildExternalProxyURLLinks(
	externalProxies []any,
	params map[string]string,
	baseSecurity string,
	makeLink func(dest string, port int) string,
	makeRemark func(ep map[string]any) string,
) string {
	links := make([]string, 0, len(externalProxies))
	for _, externalProxy := range externalProxies {
		ep, _ := externalProxy.(map[string]any)
		newSecurity, _ := ep["forceTls"].(string)
		dest, _ := ep["dest"].(string)
		port := int(ep["port"].(float64))

		securityToApply := baseSecurity
		if newSecurity != "same" {
			securityToApply = newSecurity
		}

		links = append(
			links,
			buildLinkWithParamsAndSecurity(
				makeLink(dest, port),
				params,
				makeRemark(ep),
				securityToApply,
				newSecurity == "none",
			),
		)
	}
	return strings.Join(links, "\n")
}

func cloneStringMap(source map[string]string) map[string]string {
	cloned := make(map[string]string, len(source))
	maps.Copy(cloned, source)
	return cloned
}

func (s *SubService) genRemark(inbound *model.Inbound, email string, extra string) string {
	separationChar := string(s.remarkModel[0])
	orderChars := s.remarkModel[1:]
	orders := map[byte]string{
		'i': "",
		'e': "",
		'o': "",
	}
	if len(email) > 0 {
		orders['e'] = email
	}
	if len(inbound.Remark) > 0 {
		orders['i'] = inbound.Remark
	}
	if len(extra) > 0 {
		orders['o'] = extra
	}

	var remark []string
	for i := 0; i < len(orderChars); i++ {
		char := orderChars[i]
		order, exists := orders[char]
		if exists && order != "" {
			remark = append(remark, order)
		}
	}

	if s.showInfo {
		statsExist := false
		var stats xray.ClientTraffic
		for _, clientStat := range inbound.ClientStats {
			if clientStat.Email == email {
				stats = clientStat
				statsExist = true
				break
			}
		}

		// Get remained days
		if statsExist {
			if !stats.Enable {
				return fmt.Sprintf("⛔️N/A%s%s", separationChar, strings.Join(remark, separationChar))
			}
			if vol := stats.Total - (stats.Up + stats.Down); vol > 0 {
				remark = append(remark, fmt.Sprintf("%s%s", common.FormatTraffic(vol), "📊"))
			}
			now := time.Now().Unix()
			switch exp := stats.ExpiryTime / 1000; {
			case exp > 0:
				remainingSeconds := exp - now
				days := remainingSeconds / 86400
				hours := (remainingSeconds % 86400) / 3600
				minutes := (remainingSeconds % 3600) / 60
				if days > 0 {
					if hours > 0 {
						remark = append(remark, fmt.Sprintf("%dD,%dH⏳", days, hours))
					} else {
						remark = append(remark, fmt.Sprintf("%dD⏳", days))
					}
				} else if hours > 0 {
					remark = append(remark, fmt.Sprintf("%dH⏳", hours))
				} else {
					remark = append(remark, fmt.Sprintf("%dM⏳", minutes))
				}
			case exp < 0:
				days := exp / -86400
				hours := (exp % -86400) / 3600
				minutes := (exp % -3600) / 60
				if days > 0 {
					if hours > 0 {
						remark = append(remark, fmt.Sprintf("%dD,%dH⏳", days, hours))
					} else {
						remark = append(remark, fmt.Sprintf("%dD⏳", days))
					}
				} else if hours > 0 {
					remark = append(remark, fmt.Sprintf("%dH⏳", hours))
				} else {
					remark = append(remark, fmt.Sprintf("%dM⏳", minutes))
				}
			}
		}
	}
	return strings.Join(remark, separationChar)
}

func searchKey(data any, key string) (any, bool) {
	switch val := data.(type) {
	case map[string]any:
		for k, v := range val {
			if k == key {
				return v, true
			}
			if result, ok := searchKey(v, key); ok {
				return result, true
			}
		}
	case []any:
		for _, v := range val {
			if result, ok := searchKey(v, key); ok {
				return result, true
			}
		}
	}
	return nil, false
}

// buildXhttpExtra walks an xhttpSettings map and returns the JSON blob
// that goes into the URL's `extra` param (or, for VMess, the link
// object). Carries ONLY the bidirectional fields from xray-core's
// SplitHTTPConfig — i.e. the ones the server enforces and the client
// must match. Strictly one-sided fields are excluded:
//
//   - server-only (noSSEHeader, scMaxBufferedPosts, scStreamUpServerSecs,
//     serverMaxHeaderBytes) — client wouldn't read them, so emitting
//     them just bloats the URL.
//   - client-only (headers, uplinkHTTPMethod, uplinkChunkSize,
//     noGRPCHeader, scMinPostsIntervalMs, xmux, downloadSettings) — the
//     inbound config doesn't have them; the client configures them
//     locally.
//
// Truthy-only guards keep default inbounds emitting the same compact URL
// they did before this helper grew.
func buildXhttpExtra(xhttp map[string]any) map[string]any {
	if xhttp == nil {
		return nil
	}
	extra := map[string]any{}

	if xpb, ok := xhttp["xPaddingBytes"].(string); ok && len(xpb) > 0 {
		extra["xPaddingBytes"] = xpb
	}
	if obfs, ok := xhttp["xPaddingObfsMode"].(bool); ok && obfs {
		extra["xPaddingObfsMode"] = true
		for _, field := range []string{"xPaddingKey", "xPaddingHeader", "xPaddingPlacement", "xPaddingMethod"} {
			if v, ok := xhttp[field].(string); ok && len(v) > 0 {
				extra[field] = v
			}
		}
	}

	stringFields := []string{
		"sessionPlacement", "sessionKey",
		"seqPlacement", "seqKey",
		"uplinkDataPlacement", "uplinkDataKey",
		"scMaxEachPostBytes",
	}
	for _, field := range stringFields {
		if v, ok := xhttp[field].(string); ok && len(v) > 0 {
			extra[field] = v
		}
	}

	// Headers — emitted as the {name: value} map upstream's struct
	// expects. The server runtime ignores this field, but the client
	// (consuming the share link) honors it. Drop any "host" entry —
	// host already wins as a top-level URL param.
	if rawHeaders, ok := xhttp["headers"].(map[string]any); ok && len(rawHeaders) > 0 {
		out := map[string]any{}
		for k, v := range rawHeaders {
			if strings.EqualFold(k, "host") {
				continue
			}
			out[k] = v
		}
		if len(out) > 0 {
			extra["headers"] = out
		}
	}

	if len(extra) == 0 {
		return nil
	}
	return extra
}

// applyXhttpExtraParams emits the full xhttp config into the URL query
// params of a vless:// / trojan:// / ss:// link. Sets path/host/mode at
// top level (xray's Build() always lets these win over `extra`) and packs
// everything else into a JSON `extra` param. Also writes the flat
// `x_padding_bytes` param sing-box-family clients understand.
//
// Without this, the admin's custom xPaddingBytes / sessionKey / etc. never
// reach the client and handshakes are silently rejected with
// `invalid padding (...) length: 0` — the client-visible symptom is
// "xhttp doesn't connect" on OpenWRT / sing-box.
//
// Two encodings are written so every popular client can read at least one:
//
//   - x_padding_bytes=<range>  — flat param, understood by sing-box and its
//     derivatives (Podkop, OpenWRT sing-box, Karing, NekoBox, …).
//   - extra=<url-encoded-json> — full xhttp settings blob, which is how
//     xray-core clients (v2rayNG, Happ, Furious, Exclave, …) pick up the
//     bidirectional fields beyond path/host/mode.
func applyXhttpExtraParams(xhttp map[string]any, params map[string]string) {
	if xhttp == nil {
		return
	}
	applyPathAndHostParams(xhttp, params)
	if mode, ok := xhttp["mode"].(string); ok {
		params["mode"] = mode
	}

	if xpb, ok := xhttp["xPaddingBytes"].(string); ok && len(xpb) > 0 {
		params["x_padding_bytes"] = xpb
	}

	extra := buildXhttpExtra(xhttp)
	if extra != nil {
		if b, err := json.Marshal(extra); err == nil {
			params["extra"] = string(b)
		}
	}
}

var kcpMaskToHeaderType = map[string]string{
	"header-dns":       "dns",
	"header-dtls":      "dtls",
	"header-srtp":      "srtp",
	"header-utp":       "utp",
	"header-wechat":    "wechat-video",
	"header-wireguard": "wireguard",
}

var validFinalMaskUDPTypes = map[string]struct{}{
	"salamander":       {},
	"mkcp-aes128gcm":   {},
	"header-dns":       {},
	"header-dtls":      {},
	"header-srtp":      {},
	"header-utp":       {},
	"header-wechat":    {},
	"header-wireguard": {},
	"mkcp-original":    {},
	"xdns":             {},
	"xicmp":            {},
	"noise":            {},
	"header-custom":    {},
}

var validFinalMaskTCPTypes = map[string]struct{}{
	"header-custom": {},
	"fragment":      {},
	"sudoku":        {},
}

// applyKcpShareParams reconstructs legacy KCP share-link fields from either
// the historical kcpSettings.header/seed shape or the current finalmask model.
// This keeps subscription output compatible while avoiding panics when older
// keys are absent from modern inbounds.
func applyKcpShareParams(stream map[string]any, params map[string]string) {
	extractKcpShareFields(stream).applyToParams(params)
}

func applyKcpShareObj(stream map[string]any, obj map[string]any) {
	extractKcpShareFields(stream).applyToObj(obj)
}

type kcpShareFields struct {
	headerType string
	seed       string
	mtu        int
	tti        int
}

func (f kcpShareFields) applyToParams(params map[string]string) {
	if f.headerType != "" && f.headerType != "none" {
		params["headerType"] = f.headerType
	}
	setStringParam(params, "seed", f.seed)
	setIntParam(params, "mtu", f.mtu)
	setIntParam(params, "tti", f.tti)
}

func (f kcpShareFields) applyToObj(obj map[string]any) {
	if f.headerType != "" && f.headerType != "none" {
		obj["type"] = f.headerType
	}
	setStringField(obj, "path", f.seed)
	setIntField(obj, "mtu", f.mtu)
	setIntField(obj, "tti", f.tti)
}

func extractKcpShareFields(stream map[string]any) kcpShareFields {
	fields := kcpShareFields{headerType: "none"}

	if kcp, ok := stream["kcpSettings"].(map[string]any); ok {
		if header, ok := kcp["header"].(map[string]any); ok {
			if value, ok := header["type"].(string); ok && value != "" {
				fields.headerType = value
			}
		}
		if value, ok := kcp["seed"].(string); ok && value != "" {
			fields.seed = value
		}
		if value, ok := readPositiveInt(kcp["mtu"]); ok {
			fields.mtu = value
		}
		if value, ok := readPositiveInt(kcp["tti"]); ok {
			fields.tti = value
		}
	}

	for _, rawMask := range normalizedFinalMaskUDPMasks(stream["finalmask"]) {
		mask, _ := rawMask.(map[string]any)
		if mask == nil {
			continue
		}
		maskType, _ := mask["type"].(string)
		if mapped, ok := kcpMaskToHeaderType[maskType]; ok {
			fields.headerType = mapped
			continue
		}

		switch maskType {
		case "mkcp-original":
			fields.seed = ""
		case "mkcp-aes128gcm":
			fields.seed = ""
			settings, _ := mask["settings"].(map[string]any)
			if value, ok := settings["password"].(string); ok && value != "" {
				fields.seed = value
			}
		}
	}

	return fields
}

func readPositiveInt(value any) (int, bool) {
	switch number := value.(type) {
	case int:
		return number, number > 0
	case int32:
		return int(number), number > 0
	case int64:
		return int(number), number > 0
	case float32:
		parsed := int(number)
		return parsed, parsed > 0
	case float64:
		parsed := int(number)
		return parsed, parsed > 0
	default:
		return 0, false
	}
}

func setStringParam(params map[string]string, key, value string) {
	if value == "" {
		delete(params, key)
		return
	}
	params[key] = value
}

func setIntParam(params map[string]string, key string, value int) {
	if value <= 0 {
		delete(params, key)
		return
	}
	params[key] = fmt.Sprintf("%d", value)
}

func setStringField(obj map[string]any, key, value string) {
	if value == "" {
		delete(obj, key)
		return
	}
	obj[key] = value
}

func setIntField(obj map[string]any, key string, value int) {
	if value <= 0 {
		delete(obj, key)
		return
	}
	obj[key] = value
}

// applyFinalMaskParams exports the finalmask payload as the compact
// `fm=<json>` share-link field used by v2rayN-compatible clients.
func applyFinalMaskParams(finalmask map[string]any, params map[string]string) {
	if fm, ok := marshalFinalMask(finalmask); ok {
		params["fm"] = fm
	}
}

func applyFinalMaskObj(finalmask map[string]any, obj map[string]any) {
	if fm, ok := marshalFinalMask(finalmask); ok {
		obj["fm"] = fm
	}
}

func marshalFinalMask(finalmask map[string]any) (string, bool) {
	normalized := normalizeFinalMask(finalmask)
	if !hasFinalMaskContent(normalized) {
		return "", false
	}
	b, err := json.Marshal(normalized)
	if err != nil || len(b) == 0 || string(b) == "null" {
		return "", false
	}
	return string(b), true
}

func normalizeFinalMask(finalmask map[string]any) map[string]any {
	tcpMasks := normalizedFinalMaskTCPMasks(finalmask)
	udpMasks := normalizedFinalMaskUDPMasks(finalmask)
	quicParams, hasQuicParams := finalmask["quicParams"].(map[string]any)

	if len(tcpMasks) == 0 && len(udpMasks) == 0 && !hasQuicParams {
		return nil
	}

	result := map[string]any{}
	if len(tcpMasks) > 0 {
		result["tcp"] = tcpMasks
	}
	if len(udpMasks) > 0 {
		result["udp"] = udpMasks
	}
	if hasQuicParams && len(quicParams) > 0 {
		result["quicParams"] = quicParams
	}
	return result
}

func normalizedFinalMaskTCPMasks(value any) []any {
	finalmask, _ := value.(map[string]any)
	if finalmask == nil {
		return nil
	}
	rawMasks, _ := finalmask["tcp"].([]any)
	if len(rawMasks) == 0 {
		return nil
	}

	normalized := make([]any, 0, len(rawMasks))
	for _, rawMask := range rawMasks {
		mask, _ := rawMask.(map[string]any)
		if mask == nil {
			continue
		}
		maskType, _ := mask["type"].(string)
		if _, ok := validFinalMaskTCPTypes[maskType]; !ok || maskType == "" {
			continue
		}

		normalizedMask := map[string]any{"type": maskType}
		if settings, ok := mask["settings"].(map[string]any); ok && len(settings) > 0 {
			normalizedMask["settings"] = settings
		}
		normalized = append(normalized, normalizedMask)
	}

	if len(normalized) == 0 {
		return nil
	}
	return normalized
}

func normalizedFinalMaskUDPMasks(value any) []any {
	finalmask, _ := value.(map[string]any)
	if finalmask == nil {
		return nil
	}
	rawMasks, _ := finalmask["udp"].([]any)
	if len(rawMasks) == 0 {
		return nil
	}

	normalized := make([]any, 0, len(rawMasks))
	for _, rawMask := range rawMasks {
		mask, _ := rawMask.(map[string]any)
		if mask == nil {
			continue
		}
		maskType, _ := mask["type"].(string)
		if _, ok := validFinalMaskUDPTypes[maskType]; !ok || maskType == "" {
			continue
		}

		normalizedMask := map[string]any{"type": maskType}
		if settings, ok := mask["settings"].(map[string]any); ok && len(settings) > 0 {
			normalizedMask["settings"] = settings
		}
		normalized = append(normalized, normalizedMask)
	}

	if len(normalized) == 0 {
		return nil
	}
	return normalized
}

func hasFinalMaskContent(value any) bool {
	switch v := value.(type) {
	case nil:
		return false
	case string:
		return len(v) > 0
	case map[string]any:
		for _, item := range v {
			if hasFinalMaskContent(item) {
				return true
			}
		}
		return false
	case []any:
		return slices.ContainsFunc(v, hasFinalMaskContent)
	default:
		return true
	}
}

func searchHost(headers any) string {
	data, _ := headers.(map[string]any)
	for k, v := range data {
		if strings.EqualFold(k, "host") {
			switch v.(type) {
			case []any:
				hosts, _ := v.([]any)
				if len(hosts) > 0 {
					return hosts[0].(string)
				} else {
					return ""
				}
			case any:
				return v.(string)
			}
		}
	}

	return ""
}

// PageData is a view model for subpage.html
// PageData contains data for rendering the subscription information page.
type PageData struct {
	Host         string
	BasePath     string
	SId          string
	Enabled      bool
	Download     string
	Upload       string
	Total        string
	Used         string
	Remained     string
	Expire       int64
	LastOnline   int64
	Datepicker   string
	DownloadByte int64
	UploadByte   int64
	TotalByte    int64
	SubUrl       string
	SubJsonUrl   string
	SubClashUrl  string
	Result       []string
}

// ResolveRequest extracts scheme and host info from request/headers consistently.
// ResolveRequest extracts scheme, host, and header information from an HTTP request.
func (s *SubService) ResolveRequest(c *gin.Context) (scheme string, host string, hostWithPort string, hostHeader string) {
	// scheme
	scheme = "http"
	if c.Request.TLS != nil || strings.EqualFold(c.GetHeader("X-Forwarded-Proto"), "https") {
		scheme = "https"
	}

	// base host (no port)
	if h, err := getHostFromXFH(c.GetHeader("X-Forwarded-Host")); err == nil && h != "" {
		host = h
	}
	if host == "" {
		host = c.GetHeader("X-Real-IP")
	}
	if host == "" {
		var err error
		host, _, err = net.SplitHostPort(c.Request.Host)
		if err != nil {
			host = c.Request.Host
		}
	}

	// host:port for URLs
	hostWithPort = c.GetHeader("X-Forwarded-Host")
	if hostWithPort == "" {
		hostWithPort = c.Request.Host
	}
	if hostWithPort == "" {
		hostWithPort = host
	}

	// header display host
	hostHeader = c.GetHeader("X-Forwarded-Host")
	if hostHeader == "" {
		hostHeader = c.GetHeader("X-Real-IP")
	}
	if hostHeader == "" {
		hostHeader = host
	}
	return
}

// BuildURLs constructs absolute subscription and JSON subscription URLs for a given subscription ID.
// It prioritizes configured URIs, then individual settings, and finally falls back to request-derived components.
func (s *SubService) BuildURLs(scheme, hostWithPort, subPath, subJsonPath, subClashPath, subId string) (subURL, subJsonURL, subClashURL string) {
	if subId == "" {
		return "", "", ""
	}

	configuredSubURI, _ := s.settingService.GetSubURI()
	configuredSubJsonURI, _ := s.settingService.GetSubJsonURI()
	configuredSubClashURI, _ := s.settingService.GetSubClashURI()

	var baseScheme, baseHostWithPort string
	if configuredSubURI == "" || configuredSubJsonURI == "" || configuredSubClashURI == "" {
		baseScheme, baseHostWithPort = s.getBaseSchemeAndHost(scheme, hostWithPort)
	}

	subURL = s.buildSingleURL(configuredSubURI, baseScheme, baseHostWithPort, subPath, subId)
	subJsonURL = s.buildSingleURL(configuredSubJsonURI, baseScheme, baseHostWithPort, subJsonPath, subId)
	subClashURL = s.buildSingleURL(configuredSubClashURI, baseScheme, baseHostWithPort, subClashPath, subId)

	return subURL, subJsonURL, subClashURL
}

// getBaseSchemeAndHost determines the base scheme and host from settings or falls back to request values
func (s *SubService) getBaseSchemeAndHost(requestScheme, requestHostWithPort string) (string, string) {
	subDomain, err := s.settingService.GetSubDomain()
	if err != nil || subDomain == "" {
		return requestScheme, requestHostWithPort
	}

	// Get port and TLS settings
	subPort, _ := s.settingService.GetSubPort()
	subKeyFile, _ := s.settingService.GetSubKeyFile()
	subCertFile, _ := s.settingService.GetSubCertFile()

	// Determine scheme from TLS configuration
	scheme := "http"
	if subKeyFile != "" && subCertFile != "" {
		scheme = "https"
	}

	// Build host:port, always include port for clarity
	hostWithPort := fmt.Sprintf("%s:%d", subDomain, subPort)

	return scheme, hostWithPort
}

// buildSingleURL constructs a single URL using configured URI or base components
func (s *SubService) buildSingleURL(configuredURI, baseScheme, baseHostWithPort, basePath, subId string) string {
	if configuredURI != "" {
		return s.joinPathWithID(configuredURI, subId)
	}

	baseURL := fmt.Sprintf("%s://%s", baseScheme, baseHostWithPort)
	return s.joinPathWithID(baseURL+basePath, subId)
}

// joinPathWithID safely joins a base path with a subscription ID
func (s *SubService) joinPathWithID(basePath, subId string) string {
	if strings.HasSuffix(basePath, "/") {
		return basePath + subId
	}
	return basePath + "/" + subId
}

// BuildPageData parses header and prepares the template view model.
// BuildPageData constructs page data for rendering the subscription information page.
func (s *SubService) BuildPageData(subId string, hostHeader string, traffic xray.ClientTraffic, lastOnline int64, subs []string, subURL, subJsonURL, subClashURL string, basePath string) PageData {
	download := common.FormatTraffic(traffic.Down)
	upload := common.FormatTraffic(traffic.Up)
	total := "∞"
	used := common.FormatTraffic(traffic.Up + traffic.Down)
	remained := ""
	if traffic.Total > 0 {
		total = common.FormatTraffic(traffic.Total)
		left := max(traffic.Total-(traffic.Up+traffic.Down), 0)
		remained = common.FormatTraffic(left)
	}

	datepicker := s.datepicker
	if datepicker == "" {
		datepicker = "gregorian"
	}

	return PageData{
		Host:         hostHeader,
		BasePath:     basePath,
		SId:          subId,
		Enabled:      traffic.Enable,
		Download:     download,
		Upload:       upload,
		Total:        total,
		Used:         used,
		Remained:     remained,
		Expire:       traffic.ExpiryTime / 1000,
		LastOnline:   lastOnline,
		Datepicker:   datepicker,
		DownloadByte: traffic.Down,
		UploadByte:   traffic.Up,
		TotalByte:    traffic.Total,
		SubUrl:       subURL,
		SubJsonUrl:   subJsonURL,
		SubClashUrl:  subClashURL,
		Result:       subs,
	}
}

func getHostFromXFH(s string) (string, error) {
	if strings.Contains(s, ":") {
		realHost, _, err := net.SplitHostPort(s)
		if err != nil {
			return "", err
		}
		return realHost, nil
	}
	return s, nil
}