package app

import (
	"encoding/json"
	"errors"
	"fmt"
	"infinite-canvas/backend/internal/kernel"
	stdlog "log"
	"strings"
	"time"

	"infinite-canvas/backend/internal/model"
	"infinite-canvas/backend/internal/repository"

	"gorm.io/gorm"
)

type CreateAdminUserRequest struct {
	Username    string           `json:"username"`
	DisplayName string           `json:"displayName"`
	Email       string           `json:"email"`
	Password    string           `json:"password"`
	Role        model.UserRole   `json:"role"`
	Status      model.UserStatus `json:"status"`
}
type UpdateUserRequest struct {
	DisplayName string           `json:"displayName"`
	Email       string           `json:"email"`
	Password    string           `json:"password"`
	Role        model.UserRole   `json:"role"`
	Status      model.UserStatus `json:"status"`
}

type BulkDisableUsersRequest struct {
	UserIDs []string `json:"userIds"`
}

type BulkDisableUsersResult struct {
	Users         []model.User `json:"users"`
	DisabledCount int          `json:"disabledCount"`
}

type AdminListQuery struct {
	Keyword string
	Status  string
	Type    string
	Page    int
	Limit   int
}

type AdminUserPage struct {
	Users []AdminUser `json:"users"`
	Total int64       `json:"total"`
	Page  int         `json:"page"`
	Limit int         `json:"pageSize"`
}

type AdminUser struct {
	model.User
	AvailableMicrocredits int64 `json:"availableMicrocredits"`
	ReservedMicrocredits  int64 `json:"reservedMicrocredits"`
}

type AdminChannelPage struct {
	Channels []PublicModelChannel `json:"channels"`
	Total    int64                `json:"total"`
	Page     int                  `json:"page"`
	Limit    int                  `json:"pageSize"`
}

type AdminUserReference struct {
	ID          string `json:"id"`
	Username    string `json:"username"`
	DisplayName string `json:"displayName"`
}

type AdminChannelReference struct {
	ID      string   `json:"id"`
	Name    string   `json:"name"`
	Enabled bool     `json:"enabled"`
	Models  []string `json:"models"`
}

type AdminReferenceData struct {
	Users    []AdminUserReference    `json:"users"`
	Channels []AdminChannelReference `json:"channels"`
}

type ChannelRequest struct {
	Name                 string           `json:"name"`
	SortOrder            *int             `json:"sortOrder"`
	BaseURL              string           `json:"baseUrl"`
	APIKey               string           `json:"apiKey"`
	SecretKey            string           `json:"secretKey"`
	ConcurrencyLimit     *int             `json:"concurrencyLimit"`
	UseGlobalConcurrency *bool            `json:"useGlobalConcurrency"`
	Models               []string         `json:"models"`
	Headers              []OutboundHeader `json:"headers"`
	Enabled              *bool            `json:"enabled"`
}

type PublicModelChannel struct {
	ID               string                    `json:"id"`
	UserID           string                    `json:"userId"`
	Scope            model.ChannelScope        `json:"scope"`
	Enabled          bool                      `json:"enabled"`
	Name             string                    `json:"name"`
	SortOrder        int                       `json:"sortOrder"`
	BaseURL          string                    `json:"baseUrl"`
	APIKey           string                    `json:"apiKey"`
	APIFormat        string                    `json:"apiFormat"`
	ConcurrencyLimit int                       `json:"concurrencyLimit"`
	Models           []string                  `json:"models"`
	ModelCosts       []PublicChannelModelPrice `json:"modelCosts"`
	Headers          []OutboundHeader          `json:"headers,omitempty"`
	HasAPIKey        bool                      `json:"hasApiKey"`
	HasSecretKey     bool                      `json:"hasSecretKey"`
	CreatedAt        time.Time                 `json:"createdAt"`
	UpdatedAt        time.Time                 `json:"updatedAt"`
}

type PublicChannelModelPrice struct {
	Model                        string                     `json:"model"`
	DisplayName                  string                     `json:"displayName"`
	ChannelLabel                 string                     `json:"channelLabel"`
	Description                  string                     `json:"description"`
	Icon                         string                     `json:"icon"`
	Capability                   string                     `json:"capability"`
	Protocol                     model.ChannelInterfaceType `json:"protocol"`
	BillingMode                  string                     `json:"billingMode"`
	UnitPriceMicrocredits        int64                      `json:"unitPriceMicrocredits"`
	InputTokenPriceMicrocredits  int64                      `json:"inputTokenPriceMicrocredits"`
	OutputTokenPriceMicrocredits int64                      `json:"outputTokenPriceMicrocredits"`
	CachedTokenPriceMicrocredits int64                      `json:"cachedTokenPriceMicrocredits"`
	CapabilityConfig             *ModelCapabilityConfig     `json:"capabilityConfig,omitempty"`
}

func (s *Service) RequireAdmin(user *model.User) error {
	if user == nil {
		return Unauthorized("请先登录")
	}
	if user.Role != model.UserRoleAdmin {
		return Forbidden("需要管理员权限")
	}
	return nil
}

func (s *Service) AdminUsers(actor *model.User, query AdminListQuery) (*AdminUserPage, error) {
	if err := s.RequireAdmin(actor); err != nil {
		return nil, err
	}
	page, limit := normalizeAdminPage(query.Page, query.Limit)
	users, total, err := s.repo.AdminUsers(query.Keyword, model.UserRole(query.Type), model.UserStatus(query.Status), limit, (page-1)*limit)
	if err != nil {
		return nil, err
	}
	userIDs := make([]string, 0, len(users))
	for _, user := range users {
		userIDs = append(userIDs, user.ID)
	}
	accounts, err := s.repo.CreditAccounts(userIDs)
	if err != nil {
		return nil, err
	}
	accountByUserID := make(map[string]model.CreditAccount, len(accounts))
	for _, account := range accounts {
		accountByUserID[account.UserID] = account
	}
	result := make([]AdminUser, 0, len(users))
	for _, user := range users {
		account := accountByUserID[user.ID]
		result = append(result, AdminUser{User: user, AvailableMicrocredits: account.AvailableMicrocredits, ReservedMicrocredits: account.ReservedMicrocredits})
	}
	return &AdminUserPage{Users: result, Total: total, Page: page, Limit: limit}, nil
}

func (s *Service) AdminReferences(actor *model.User) (*AdminReferenceData, error) {
	if err := s.RequireAdmin(actor); err != nil {
		return nil, err
	}
	users, err := s.repo.AdminUserReferences()
	if err != nil {
		return nil, err
	}
	channels, err := s.repo.AdminSystemChannelReferences()
	if err != nil {
		return nil, err
	}
	result := &AdminReferenceData{
		Users:    make([]AdminUserReference, 0, len(users)),
		Channels: make([]AdminChannelReference, 0, len(channels)),
	}
	for _, user := range users {
		result.Users = append(result.Users, AdminUserReference{ID: user.ID, Username: user.Username, DisplayName: user.DisplayName})
	}
	for _, channel := range channels {
		items, itemErr := s.repo.ChannelModels(channel.ID, false)
		if itemErr != nil {
			return nil, itemErr
		}
		models := make([]string, 0, len(items))
		for _, item := range items {
			models = append(models, item.ModelKey)
		}
		result.Channels = append(result.Channels, AdminChannelReference{ID: channel.ID, Name: channel.Name, Enabled: channel.Enabled, Models: uniqueNonEmpty(models)})
	}
	return result, nil
}

func (s *Service) CreateAdminUser(actor *model.User, req CreateAdminUserRequest) (*AdminUser, error) {
	if err := s.RequireAdmin(actor); err != nil {
		return nil, err
	}
	username := normalizeUsername(req.Username)
	email := normalizeEmail(req.Email)
	displayName := normalizeDisplayName(req.DisplayName, username)
	if err := validateUsername(username); err != nil {
		return nil, err
	}
	if err := validatePassword(req.Password); err != nil {
		return nil, err
	}
	if email != "" {
		if err := validateEmail(email); err != nil {
			return nil, err
		}
	}
	if req.Role != model.UserRoleAdmin && req.Role != model.UserRoleUser {
		return nil, BadAuthRequest("\u7528\u6237\u89d2\u8272\u65e0\u6548")
	}
	if req.Status != model.UserStatusActive && req.Status != model.UserStatusDisabled {
		return nil, BadAuthRequest("\u7528\u6237\u72b6\u6001\u65e0\u6548")
	}
	if _, err := s.repo.UserByUsername(username); err == nil {
		return nil, BadAuthRequest("\u7528\u6237\u540d\u5df2\u5b58\u5728")
	} else if !errors.Is(err, gorm.ErrRecordNotFound) {
		return nil, err
	}
	if email != "" {
		if _, err := s.repo.UserByEmail(email); err == nil {
			return nil, BadAuthRequest("\u90ae\u7bb1\u5df2\u88ab\u6ce8\u518c")
		} else if !errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, err
		}
	}
	passwordHash, err := hashPassword(req.Password)
	if err != nil {
		return nil, err
	}
	now := time.Now()
	user := &model.User{
		ID:           newID(),
		Username:     username,
		Email:        email,
		DisplayName:  displayName,
		Role:         req.Role,
		Status:       req.Status,
		PasswordHash: passwordHash,
		CreatedAt:    now,
		UpdatedAt:    now,
	}
	if err := s.repo.Create(user); err != nil {
		return nil, err
	}
	if err := s.ensureSignupBonus(user.ID); err != nil {
		return nil, err
	}
	if err := s.appendAdminAudit(actor, "user.create", "user", user.ID, "\u521b\u5efa\u7528\u6237\u8d26\u53f7", map[string]any{"role": user.Role, "status": user.Status}); err != nil {
		return nil, err
	}
	account, err := s.repo.CreditAccount(user.ID)
	if err != nil {
		return nil, err
	}
	return &AdminUser{
		User:                  *user,
		AvailableMicrocredits: account.AvailableMicrocredits,
		ReservedMicrocredits:  account.ReservedMicrocredits,
	}, nil
}

func (s *Service) UpdateUser(actor *model.User, userID string, req UpdateUserRequest) (*model.User, error) {
	if err := s.RequireAdmin(actor); err != nil {
		return nil, err
	}
	user, err := s.repo.User(userID)
	if err != nil {
		return nil, err
	}
	if actor.ID == user.ID && req.Status == model.UserStatusDisabled {
		return nil, BadAuthRequest("不能禁用当前管理员账号")
	}
	nextRole := user.Role
	if req.Role == model.UserRoleAdmin || req.Role == model.UserRoleUser {
		nextRole = req.Role
	}
	nextStatus := user.Status
	if req.Status == model.UserStatusActive || req.Status == model.UserStatusDisabled {
		nextStatus = req.Status
	}
	if user.Role == model.UserRoleAdmin && nextRole != model.UserRoleAdmin {
		count, err := s.repo.ActiveAdminCountExcluding(user.ID)
		if err != nil {
			return nil, err
		}
		if count == 0 {
			return nil, BadAuthRequest("至少需要保留一个管理员")
		}
	}
	if user.Role == model.UserRoleAdmin && nextStatus != model.UserStatusActive {
		count, err := s.repo.ActiveAdminCountExcluding(user.ID)
		if err != nil {
			return nil, err
		}
		if count == 0 {
			return nil, BadAuthRequest("至少需要保留一个可用管理员")
		}
	}
	if strings.TrimSpace(req.DisplayName) != "" {
		user.DisplayName = normalizeDisplayName(req.DisplayName, user.Username)
	}
	if req.Email != "" {
		email := normalizeEmail(req.Email)
		if err := validateEmail(email); err != nil {
			return nil, err
		}
		existing, err := s.repo.UserByEmail(email)
		if err == nil && existing.ID != user.ID {
			return nil, BadAuthRequest("邮箱已被注册")
		}
		if err != nil && !errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, err
		}
		user.Email = email
	}
	if req.Password != "" {
		if err := validatePassword(req.Password); err != nil {
			return nil, err
		}
		hash, err := hashPassword(req.Password)
		if err != nil {
			return nil, err
		}
		user.PasswordHash = hash
		if err := s.repo.DeleteUserAuthSessions(user.ID); err != nil {
			return nil, fmt.Errorf("清理旧登录会话失败，密码未更新：%w", err)
		}
	}
	user.Role = nextRole
	user.Status = nextStatus
	user.UpdatedAt = time.Now()
	if err := s.repo.Save(user); err != nil {
		return nil, err
	}
	if err := s.appendAdminAudit(actor, "user.update", "user", user.ID, "更新用户账号状态或资料", map[string]any{"role": user.Role, "status": user.Status}); err != nil {
		return nil, err
	}
	return user, nil
}

func (s *Service) DeleteUser(actor *model.User, userID string) error {
	if err := s.RequireAdmin(actor); err != nil {
		return err
	}
	if actor.ID == userID {
		return BadAuthRequest("不能删除当前登录的管理员账号")
	}
	user, err := s.repo.User(userID)
	if err != nil {
		return err
	}
	if user.Role == model.UserRoleAdmin {
		count, err := s.repo.ActiveAdminCountExcluding(user.ID)
		if err != nil {
			return err
		}
		if count == 0 {
			return BadAuthRequest("至少需要保留一个管理员")
		}
	}
	if err := s.repo.DeleteUserAuthSessions(user.ID); err != nil {
		return err
	}
	if err := s.repo.DeleteUserTaskTextDeltas(user.ID); err != nil {
		return err
	}
	// 有资金流水后必须保留用户主体，删除入口改为停用并清除全部登录态。
	user.Status = model.UserStatusDisabled
	user.UpdatedAt = time.Now()
	if err := s.repo.Save(user); err != nil {
		return err
	}
	return s.appendAdminAudit(actor, "user.disable", "user", user.ID, "停用用户并清除登录态", nil)
}

func (s *Service) BulkDisableUsers(actor *model.User, req BulkDisableUsersRequest) (*BulkDisableUsersResult, error) {
	if err := s.RequireAdmin(actor); err != nil {
		return nil, err
	}
	seen := make(map[string]struct{}, len(req.UserIDs))
	userIDs := make([]string, 0, len(req.UserIDs))
	for _, rawID := range req.UserIDs {
		id := strings.TrimSpace(rawID)
		if id == "" {
			return nil, BadAuthRequest("用户 ID 无效")
		}
		if _, exists := seen[id]; exists {
			continue
		}
		seen[id] = struct{}{}
		userIDs = append(userIDs, id)
	}
	if len(userIDs) == 0 {
		return nil, BadAuthRequest("请选择要停用的用户")
	}
	if len(userIDs) > 100 {
		return nil, BadAuthRequest("单次最多停用 100 个用户")
	}
	metadata, err := json.Marshal(map[string]any{"userIds": userIDs, "count": len(userIDs)})
	if err != nil {
		return nil, err
	}
	now := time.Now()
	events := make([]model.AdminAuditEvent, 0, len(userIDs))
	for _, userID := range userIDs {
		events = append(events, model.AdminAuditEvent{ID: newID(), ActorUserID: actor.ID, Action: "user.bulk_disable", TargetType: "user", TargetID: userID, Summary: "批量停用用户并清除登录态", MetadataJSON: string(metadata), CreatedAt: now})
	}
	users, err := s.repo.BulkDisableUsers(actor.ID, userIDs, events, now)
	if errors.Is(err, repository.ErrBulkUserNotFound) {
		return nil, BadAuthRequest("部分用户不存在，请刷新列表后重试")
	}
	if errors.Is(err, repository.ErrBulkCurrentAdmin) {
		return nil, BadAuthRequest("不能停用当前登录的管理员账号")
	}
	if errors.Is(err, repository.ErrBulkLastActiveAdmin) {
		return nil, BadAuthRequest("批量操作后至少需要保留一个可用管理员")
	}
	if err != nil {
		return nil, err
	}
	return &BulkDisableUsersResult{Users: users, DisabledCount: len(users)}, nil
}

func (s *Service) PublicSystemChannels() ([]PublicModelChannel, error) {
	channels, err := s.repo.SystemChannels(false)
	if err != nil {
		return nil, err
	}
	result := make([]PublicModelChannel, 0, len(channels))
	for _, channel := range channels {
		items, itemErr := s.repo.ChannelModels(channel.ID, false)
		if itemErr != nil {
			return nil, itemErr
		}
		result = append(result, publicChannel(channel, false, items))
	}
	return result, nil
}

func (s *Service) SystemChannel(id string) (*model.ModelChannel, error) {
	channel, err := s.repo.SystemChannel(id)
	if err != nil {
		return nil, err
	}
	if err := s.decryptSystemChannelSecrets(channel); err != nil {
		return nil, err
	}
	return channel, nil
}

func (s *Service) adminSystemChannel(id string) (*model.ModelChannel, error) {
	channel, err := s.repo.AdminSystemChannel(id)
	if err != nil {
		return nil, err
	}
	if err := s.decryptSystemChannelSecrets(channel); err != nil {
		return nil, err
	}
	return channel, nil
}

func (s *Service) AdminSystemChannelPage(actor *model.User, query AdminListQuery) (*AdminChannelPage, error) {
	if err := s.RequireAdmin(actor); err != nil {
		return nil, err
	}
	page, limit := normalizeAdminPage(query.Page, query.Limit)
	channels, total, err := s.repo.AdminSystemChannels(query.Keyword, query.Status, limit, (page-1)*limit)
	if err != nil {
		return nil, err
	}
	result := make([]PublicModelChannel, 0, len(channels))
	for _, channel := range channels {
		items, itemErr := s.repo.ChannelModels(channel.ID, true)
		if itemErr != nil {
			return nil, itemErr
		}
		result = append(result, publicChannel(channel, true, items))
	}
	return &AdminChannelPage{Channels: result, Total: total, Page: page, Limit: limit}, nil
}

func normalizeAdminPage(page int, limit int) (int, int) {
	if page <= 0 {
		page = 1
	}
	if limit <= 0 || limit > 100 {
		limit = 20
	}
	return page, limit
}

func (s *Service) CreateSystemChannel(actor *model.User, req ChannelRequest) (*PublicModelChannel, error) {
	if err := s.RequireAdmin(actor); err != nil {
		return nil, err
	}
	channelID, err := s.repo.NextPrefixedID("CHANNEL")
	if err != nil {
		return nil, err
	}
	channel, err := s.channelFromRequest(req, model.ModelChannel{ID: channelID, UserID: actor.ID, Scope: model.ChannelScopeSystem, Enabled: true})
	if err != nil {
		return nil, err
	}
	if err := s.encryptSystemChannelSecrets(&channel); err != nil {
		return nil, err
	}
	if err := s.repo.Create(&channel); err != nil {
		return nil, err
	}
	if err := s.syncInitialChannelModels(&channel, req.Models); err != nil {
		return nil, err
	}
	s.invalidateRouteCatalog()
	items, err := s.repo.ChannelModels(channel.ID, true)
	if err != nil {
		return nil, err
	}
	public := publicChannel(channel, true, items)
	return &public, nil
}

func (s *Service) DuplicateSystemChannel(actor *model.User, id string) (*PublicModelChannel, error) {
	if err := s.RequireAdmin(actor); err != nil {
		return nil, err
	}
	source, err := s.adminSystemChannel(id)
	if err != nil {
		return nil, err
	}
	sourceModels, err := s.repo.ChannelModels(source.ID, true)
	if err != nil {
		return nil, err
	}
	if len(sourceModels) == 0 {
		for _, name := range channelModelNames(*source) {
			sourceModels = append(sourceModels, model.ChannelModel{ModelKey: name, ProviderModelKey: name, DisplayName: name, BillingMode: "fixed_request", Enabled: false, PriceVersion: 1})
		}
	}
	channelID, err := s.repo.NextPrefixedID("CHANNEL")
	if err != nil {
		return nil, err
	}
	channel := *source
	channel.ID = channelID
	channel.UserID = actor.ID
	channel.Scope = model.ChannelScopeSystem
	channel.Name = duplicateChannelName(source.Name)
	channel.CreatedAt = time.Time{}
	channel.UpdatedAt = time.Time{}
	channel.DeletedAt = gorm.DeletedAt{}
	if err := s.encryptSystemChannelSecrets(&channel); err != nil {
		return nil, err
	}

	channelModels := make([]model.ChannelModel, 0, len(sourceModels))
	priceTiers := make([]model.ChannelModelPriceTier, 0)
	for _, sourceModel := range sourceModels {
		modelID, idErr := s.repo.NextPrefixedID("MODEL")
		if idErr != nil {
			return nil, idErr
		}
		channelModel := sourceModel
		channelModel.ID = modelID
		channelModel.ChannelID = channel.ID
		channelModel.CreatedAt = time.Time{}
		channelModel.UpdatedAt = time.Time{}
		channelModel.DeletedAt = gorm.DeletedAt{}
		channelModel.PriceTiers = nil
		channelModels = append(channelModels, channelModel)
		for _, sourceTier := range sourceModel.PriceTiers {
			tierID, tierErr := s.repo.NextPrefixedID("PTIER")
			if tierErr != nil {
				return nil, tierErr
			}
			priceTier := sourceTier
			priceTier.ID = tierID
			priceTier.ChannelModelID = channelModel.ID
			priceTier.Selector = nil
			priceTier.CreatedAt = time.Time{}
			priceTier.UpdatedAt = time.Time{}
			priceTier.DeletedAt = gorm.DeletedAt{}
			priceTiers = append(priceTiers, priceTier)
		}
	}
	if err := s.repo.CreateDuplicatedSystemChannel(&channel, channelModels, priceTiers); err != nil {
		return nil, err
	}
	s.invalidateRouteCatalog()
	items, err := s.repo.ChannelModels(channel.ID, true)
	if err != nil {
		return nil, err
	}
	public := publicChannel(channel, true, items)
	return &public, nil
}

func duplicateChannelName(name string) string {
	const suffix = " - 副本"
	base := []rune(strings.TrimSpace(name))
	if len(base) == 0 {
		base = []rune("系统渠道")
	}
	if len(base)+len([]rune(suffix)) > 80 {
		base = base[:80-len([]rune(suffix))]
	}
	return string(base) + suffix
}

func (s *Service) UpdateSystemChannel(actor *model.User, id string, req ChannelRequest) (*PublicModelChannel, error) {
	if err := s.RequireAdmin(actor); err != nil {
		return nil, err
	}
	if req.presentationOnly() {
		return s.updateChannelPresentation(id, req)
	}
	updateModels := req.Models != nil
	channel, err := s.repo.AdminSystemChannel(id)
	if err != nil {
		return nil, err
	}
	if err := s.decryptSystemChannelSecrets(channel); err != nil {
		return nil, err
	}
	req = mergeChannelRequest(req, *channel)
	next, err := s.channelFromRequest(req, *channel)
	if err != nil {
		return nil, err
	}
	next.ID = channel.ID
	next.UserID = channel.UserID
	next.Scope = model.ChannelScopeSystem
	next.CreatedAt = channel.CreatedAt
	if req.APIKey == "" {
		next.APIKey = channel.APIKey
	}
	if req.SecretKey == "" {
		next.SecretKey = channel.SecretKey
	}
	if err := s.encryptSystemChannelSecrets(&next); err != nil {
		return nil, err
	}
	if err := s.repo.Save(&next); err != nil {
		return nil, err
	}
	if updateModels {
		if err := s.syncInitialChannelModels(&next, req.Models); err != nil {
			return nil, err
		}
	}
	s.invalidateRouteCatalog()
	items, err := s.repo.ChannelModels(next.ID, true)
	if err != nil {
		return nil, err
	}
	public := publicChannel(next, true, items)
	return &public, nil
}

func (s *Service) encryptSystemChannelSecrets(channel *model.ModelChannel) error {
	apiKey, err := s.encryptSettingSecret(channel.APIKey)
	if err != nil {
		return err
	}
	secretKey, err := s.encryptSettingSecret(channel.SecretKey)
	if err != nil {
		return err
	}
	channel.APIKey = apiKey
	channel.SecretKey = secretKey
	return nil
}

func (s *Service) decryptSystemChannelSecrets(channel *model.ModelChannel) error {
	apiKey, err := s.decryptSettingSecret(channel.APIKey)
	if err != nil {
		return err
	}
	secretKey, err := s.decryptSettingSecret(channel.SecretKey)
	if err != nil {
		return err
	}
	channel.APIKey = apiKey
	channel.SecretKey = secretKey
	return nil
}

func (s *Service) DeleteSystemChannel(actor *model.User, id string) error {
	if err := s.RequireAdmin(actor); err != nil {
		return err
	}
	channel, err := s.repo.AdminSystemChannel(id)
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return BadAuthRequest("系统渠道不存在或已删除")
		}
		return err
	}
	// 保留主体供历史账单和调用日志关联，但从所有业务查询中隐藏并清除密钥。
	err = s.repo.DeleteSystemChannel(channel.ID)
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return BadAuthRequest("系统渠道不存在或已删除")
	}
	if err == nil {
		s.invalidateRouteCatalog()
	}
	return err
}

func (s *Service) LogAPICall(log model.ApiCallLog) error {
	if log.ID == "" {
		log.ID = newID()
	}
	if log.CreatedAt.IsZero() {
		log.CreatedAt = time.Now()
	}
	if log.StartedAt.IsZero() {
		log.StartedAt = log.CreatedAt.Add(-time.Duration(log.DurationMs) * time.Millisecond)
	}
	s.estimateCallCost(&log)
	if log.BillingOrderID != "" && log.ProviderRequestID != "" {
		if err := s.repo.UpdateBillingProviderRequestID(log.BillingOrderID, log.ProviderRequestID); err != nil {
			// 账单关联是请求日志的辅助状态，不能因为关联更新失败而丢失
			// 已经发生的上游调用记录。后续由任务/账单对账流程补偿关联。
			stdlog.Printf("provider billing request id update failed: billing_order_id=%s provider_request_id=%s error=%v", log.BillingOrderID, log.ProviderRequestID, err)
		}
	}
	if log.TaskID != "" {
		stage := log.RequestKind
		var nextPollAt *time.Time
		if stage == "create" && log.Status == model.ApiCallStatusSucceeded && log.ProviderRequestID != "" {
			stage = "accepted"
			delay := 2 * time.Second
			if log.Capability == "video" {
				delay = defaultVideoPollInterval
			}
			next := time.Now().Add(delay)
			nextPollAt = &next
		} else if stage == "poll" {
			delay := 5 * time.Second
			if log.Capability == "video" {
				delay = defaultVideoPollInterval
			}
			next := time.Now().Add(delay)
			nextPollAt = &next
		}
		if err := s.repo.UpdateTaskProviderState(log.TaskID, log.ProviderRequestID, stage, nextPollAt); err != nil {
			// 请求日志本身仍需保留；任务状态可由后续任务收尾或恢复流程
			// 重建，不能让一次状态写失败掩盖真实的上游调用。
			stdlog.Printf("provider task state update failed: task_id=%s provider_request_id=%s error=%v", log.TaskID, log.ProviderRequestID, err)
		}
	}
	if merged, err := s.mergeVideoAPICallLog(log); err != nil {
		return err
	} else if merged {
		return nil
	}
	policy, err := s.RuntimePolicy()
	if err != nil {
		return err
	}
	s.storageMu.Lock()
	defer s.storageMu.Unlock()
	usage, err := s.repo.UserStorageUsage(log.UserID)
	if err != nil {
		return err
	}
	incomingBytes := int64(len(log.Path) + len(log.Model) + len(log.ProviderRequestID) + len(log.ErrorCode) + len(log.Error) + len(log.UpstreamURL) + len(log.RequestContentType) + len(log.RequestBody) + len(log.ResponseBody))
	if err := validateAPICallLogQuotaWithPolicy(usage, incomingBytes, policy.Resource); err != nil {
		return err
	}
	return s.repo.Create(&log)
}

func (s *Service) mergeVideoAPICallLog(log model.ApiCallLog) (bool, error) {
	if log.Capability != "video" || (log.RequestKind != "poll" && log.RequestKind != "download") {
		return false, nil
	}
	if log.TaskID == "" && log.ProviderRequestID == "" {
		return false, nil
	}
	root, err := s.repo.VideoAPICallRoot(log)
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return false, nil
	}
	if err != nil {
		return false, err
	}
	if log.RequestKind == "poll" {
		root.PollCount++
		if log.ResponseBody != "" {
			root.ResponseBody = log.ResponseBody
		}
	}
	if log.ProviderRequestID != "" {
		root.ProviderRequestID = log.ProviderRequestID
	}
	if log.ProviderStatus != "" {
		root.ProviderStatus = log.ProviderStatus
	}
	startedAt := root.StartedAt
	if startedAt.IsZero() {
		startedAt = root.CreatedAt.Add(-time.Duration(root.DurationMs) * time.Millisecond)
		root.StartedAt = startedAt
	}
	root.DurationMs = max(root.DurationMs, log.CreatedAt.Sub(startedAt).Milliseconds())
	root.StatusCode = log.StatusCode
	root.ConcurrencyLimit = log.ConcurrencyLimit
	if log.Status == model.ApiCallStatusFailed {
		root.Status = log.Status
		root.ErrorCode = log.ErrorCode
		root.Error = log.Error
	} else {
		root.Status = model.ApiCallStatusSucceeded
		root.ErrorCode = ""
		root.Error = ""
	}
	if log.UsageAvailable {
		root.UsageAvailable = true
		root.InputTokens = log.InputTokens
		root.OutputTokens = log.OutputTokens
		root.CachedTokens = log.CachedTokens
	}
	return true, s.repo.Save(root)
}

func (s *Service) APICallLogs(actor *model.User, limit int) ([]model.ApiCallLog, error) {
	if actor == nil {
		return nil, Unauthorized("请先登录")
	}
	return s.repo.ApiCallLogs(actor.ID, actor.Role == model.UserRoleAdmin, limit)
}

func channelFromRequest(req ChannelRequest, channel model.ModelChannel) (model.ModelChannel, error) {
	return (&Service{}).channelFromRequest(req, channel)
}

func (s *Service) channelFromRequest(req ChannelRequest, channel model.ModelChannel) (model.ModelChannel, error) {
	name := strings.TrimSpace(req.Name)
	baseURL := strings.TrimSpace(req.BaseURL)
	if name == "" {
		return channel, BadAuthRequest("请填写渠道名称")
	}
	if baseURL == "" {
		return channel, BadAuthRequest("请填写 Base URL")
	}
	// 启用/停用或只修改价格、模型等配置时，不应要求上游域名当前可解析。
	// 只有 Base URL 实际变化时才做出站地址校验。
	connectionChanged := strings.TrimRight(baseURL, "/") != strings.TrimRight(channel.BaseURL, "/")
	if connectionChanged {
		if _, err := ValidateOutboundURL(baseURL); err != nil {
			return channel, err
		}
	}
	models := uniqueNonEmpty(req.Models)
	modelsJSON, _ := json.Marshal(models)
	headersJSON, err := EncodeOutboundHeadersJSON(req.Headers)
	if err != nil {
		return channel, err
	}
	channel.Name = name
	if req.SortOrder != nil {
		if err := validateChannelSortOrder(*req.SortOrder); err != nil {
			return channel, err
		}
		channel.SortOrder = *req.SortOrder
	}
	channel.BaseURL = strings.TrimRight(baseURL, "/")
	if req.APIKey != "" {
		channel.APIKey = req.APIKey
	}
	if req.SecretKey != "" {
		channel.SecretKey = req.SecretKey
	}
	// 系统渠道只保存地址与凭证；实际协议和鉴权方式由所选模型决定。
	channel.APIFormat = "openai"
	if req.UseGlobalConcurrency != nil && *req.UseGlobalConcurrency {
		channel.ConcurrencyLimit = 0
	} else if req.ConcurrencyLimit != nil {
		if *req.ConcurrencyLimit < minChannelConcurrencyLimit || *req.ConcurrencyLimit > maxChannelConcurrencyLimit {
			return channel, BadAuthRequest("最大并发数必须是 1-999 的整数")
		}
		channel.ConcurrencyLimit = *req.ConcurrencyLimit
	} else if req.UseGlobalConcurrency != nil {
		return channel, BadAuthRequest("请填写渠道最大并发数")
	}
	channel.ModelsJSON = string(modelsJSON)
	channel.HeadersJSON = headersJSON
	if req.Enabled != nil {
		channel.Enabled = *req.Enabled
	}
	return channel, nil
}

func mergeChannelRequest(req ChannelRequest, channel model.ModelChannel) ChannelRequest {
	if strings.TrimSpace(req.Name) == "" {
		req.Name = channel.Name
	}
	if strings.TrimSpace(req.BaseURL) == "" {
		req.BaseURL = channel.BaseURL
	}
	if req.Models == nil {
		req.Models = channelModelNames(channel)
	}
	if req.Headers == nil {
		req.Headers, _ = ParseOutboundHeadersJSON(channel.HeadersJSON)
	}
	return req
}

func publicChannel(channel model.ModelChannel, admin bool, channelModels []model.ChannelModel) PublicModelChannel {
	models := make([]string, 0, len(channelModels))
	modelCosts := make([]PublicChannelModelPrice, 0, len(channelModels))
	for _, item := range channelModels {
		if !item.Enabled {
			continue
		}
		models = append(models, item.ModelKey)
		if item.Enabled && item.PriceConfigured {
			capabilityConfig, decodeErr := DecodeModelCapabilityConfig(item.CapabilityConfigJSON)
			if decodeErr == nil && capabilityConfig != nil {
				if normalized, normalizeErr := NormalizeModelCapabilityConfigForModel(item.Capability, string(item.Protocol), firstNonEmpty(item.ProviderModelKey, item.ModelKey), capabilityConfig); normalizeErr == nil {
					capabilityConfig = normalized
				}
			}
			modelCosts = append(modelCosts, PublicChannelModelPrice{Model: item.ModelKey, DisplayName: item.DisplayName, ChannelLabel: item.ChannelLabel, Description: item.Description, Icon: item.Icon, Capability: item.Capability, Protocol: item.Protocol, BillingMode: item.BillingMode, UnitPriceMicrocredits: item.UnitPriceMicrocredits, InputTokenPriceMicrocredits: item.InputTokenPriceMicrocredits, OutputTokenPriceMicrocredits: item.OutputTokenPriceMicrocredits, CachedTokenPriceMicrocredits: item.CachedTokenPriceMicrocredits, CapabilityConfig: capabilityConfig})
		}
	}
	if len(models) == 0 {
		_ = json.Unmarshal([]byte(channel.ModelsJSON), &models)
	}
	apiKey := ""
	baseURL := channel.BaseURL
	var headers []OutboundHeader
	if channel.Scope == model.ChannelScopeSystem {
		if !admin {
			apiKey = "system"
			baseURL = "/api/ai/system/" + channel.ID
		}
		if admin {
			headers, _ = ParseOutboundHeadersJSON(channel.HeadersJSON)
		}
	} else if admin {
		apiKey = channel.APIKey
	}
	return PublicModelChannel{
		ID:               channel.ID,
		UserID:           channel.UserID,
		Scope:            channel.Scope,
		Enabled:          channel.Enabled,
		Name:             channel.Name,
		SortOrder:        channel.SortOrder,
		BaseURL:          baseURL,
		APIKey:           apiKey,
		APIFormat:        channel.APIFormat,
		ConcurrencyLimit: channel.ConcurrencyLimit,
		Models:           models,
		ModelCosts:       modelCosts,
		Headers:          headers,
		HasAPIKey:        strings.TrimSpace(channel.APIKey) != "",
		HasSecretKey:     strings.TrimSpace(channel.SecretKey) != "",
		CreatedAt:        channel.CreatedAt,
		UpdatedAt:        channel.UpdatedAt,
	}
}

func uniqueNonEmpty(values []string) []string {
	return kernel.UniqueNonEmpty(values)
}