feat(admin): 完善站点设置、内容回收站与后台菜单分组

新增站点设置与内容管理（含已删除恢复/清除），用户页改用独有运营指标，并按概览/内容/成员与经济/站点重组侧栏。

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/service/setting.go

@@ -3,7 +3,9 @@ package service
 import (
 	"errors"
 	"regexp"
+	"strconv"
 	"strings"
+	"unicode/utf8"
 
 	"github.com/freefire/jiang13-bbs/model"
 	"gorm.io/gorm"
@@ -15,14 +17,40 @@ const (
 	SettingKeyAccent = "theme_accent"
 	// SettingKeyTrustReviewedPublish 已过审用户后续发帖/评论免审；缺行视为开启（默认开）
 	SettingKeyTrustReviewedPublish = "trust_reviewed_publish"
+	SettingKeySiteName             = "site_name"
+	SettingKeySiteDescription      = "site_description"
+	SettingKeyAllowRegister        = "allow_register"
+	SettingKeyPostCooldownHours    = "post_cooldown_hours"
+)
+
+const (
+	DefaultSiteName        = "姜十三论坛"
+	DefaultSiteDescription = "姜十三论坛 - 技术分享与讨论社区"
+	DefaultCooldownHours   = 24
+	MaxSiteNameRunes       = 32
+	MaxSiteDescRunes       = 160
+	MaxCooldownHours       = 168
 )
 
 // ErrInvalidAccent 主题色格式非法
 var ErrInvalidAccent = errors.New("主题色格式不正确，应为 #RRGGBB")
 
+// ErrInvalidSiteSetting 站点设置字段校验失败
+var ErrInvalidSiteSetting = errors.New("站点设置参数无效")
+
 var accentHexRe = regexp.MustCompile(`^#[0-9a-fA-F]{6}$`)
 
-// SettingService 站点级键值设置（主题色等外观配置）
+// PublicSiteSettings 对前台公开的站点配置（SEO / 注册入口 / 发帖冷静期提示）
+type PublicSiteSettings struct {
+	Accent                string `json:"accent"`
+	TrustReviewedPublish  bool   `json:"trust_reviewed_publish"`
+	SiteName              string `json:"site_name"`
+	SiteDescription       string `json:"site_description"`
+	AllowRegister         bool   `json:"allow_register"`
+	PostCooldownHours     int    `json:"post_cooldown_hours"`
+}
+
+// SettingService 站点级键值设置
 type SettingService struct {
 	db *gorm.DB
 }
@@ -31,59 +59,195 @@ func NewSettingService(db *gorm.DB) *SettingService {
 	return &SettingService{db: db}
 }
 
-// AccentColor 返回配置的主题色（小写 #rrggbb）；未配置时返回空串，表示走前端默认色
-func (s *SettingService) AccentColor() (string, error) {
+func (s *SettingService) getValue(key string) (string, bool, error) {
 	var st model.SiteSetting
-	err := s.db.Where("key = ?", SettingKeyAccent).First(&st).Error
+	err := s.db.Where("key = ?", key).First(&st).Error
 	if errors.Is(err, gorm.ErrRecordNotFound) {
-		return "", nil
+		return "", false, nil
 	}
 	if err != nil {
+		return "", false, err
+	}
+	return st.Value, true, nil
+}
+
+func (s *SettingService) putValue(key, value string) error {
+	st := model.SiteSetting{Key: key, Value: value}
+	return s.db.Save(&st).Error
+}
+
+func (s *SettingService) deleteKey(key string) error {
+	return s.db.Where("key = ?", key).Delete(&model.SiteSetting{}).Error
+}
+
+// 缺行或空值视为 on；仅显式 false/0/off/no 为关。不用 GORM bool default:true，避免零值省略。
+func parseBoolDefaultTrue(v string, found bool) bool {
+	if !found {
+		return true
+	}
+	switch strings.TrimSpace(strings.ToLower(v)) {
+	case "false", "0", "off", "no":
+		return false
+	default:
+		return true
+	}
+}
+
+func (s *SettingService) setBoolDefaultTrue(key string, on bool) error {
+	if on {
+		return s.deleteKey(key)
+	}
+	return s.putValue(key, "false")
+}
+
+// Public 返回解析后的公开站点设置（缺省已填默认值）
+func (s *SettingService) Public() (PublicSiteSettings, error) {
+	out := PublicSiteSettings{
+		SiteName:             DefaultSiteName,
+		SiteDescription:      DefaultSiteDescription,
+		TrustReviewedPublish: true,
+		AllowRegister:        true,
+		PostCooldownHours:    DefaultCooldownHours,
+	}
+	accent, err := s.AccentColor()
+	if err != nil {
+		return out, err
+	}
+	out.Accent = accent
+
+	trust, err := s.TrustReviewedPublish()
+	if err != nil {
+		return out, err
+	}
+	out.TrustReviewedPublish = trust
+
+	name, found, err := s.getValue(SettingKeySiteName)
+	if err != nil {
+		return out, err
+	}
+	if found {
+		name = strings.TrimSpace(name)
+		if name != "" {
+			out.SiteName = name
+		}
+	}
+
+	desc, found, err := s.getValue(SettingKeySiteDescription)
+	if err != nil {
+		return out, err
+	}
+	if found {
+		out.SiteDescription = strings.TrimSpace(desc)
+	}
+
+	reg, found, err := s.getValue(SettingKeyAllowRegister)
+	if err != nil {
+		return out, err
+	}
+	out.AllowRegister = parseBoolDefaultTrue(reg, found)
+
+	hours, err := s.PostCooldownHours()
+	if err != nil {
+		return out, err
+	}
+	out.PostCooldownHours = hours
+	return out, nil
+}
+
+// AccentColor 返回配置的主题色（小写 #rrggbb）；未配置时返回空串，表示走前端默认色
+func (s *SettingService) AccentColor() (string, error) {
+	v, found, err := s.getValue(SettingKeyAccent)
+	if err != nil || !found {
 		return "", err
 	}
-	return strings.ToLower(st.Value), nil
+	return strings.ToLower(v), nil
 }
 
 // SetAccent 校验并保存主题色；hex 传空串表示恢复默认（删除该键）
 func (s *SettingService) SetAccent(hex string) error {
 	hex = strings.TrimSpace(strings.ToLower(hex))
 	if hex == "" {
-		return s.db.Where("key = ?", SettingKeyAccent).Delete(&model.SiteSetting{}).Error
+		return s.deleteKey(SettingKeyAccent)
 	}
 	if !accentHexRe.MatchString(hex) {
 		return ErrInvalidAccent
 	}
-	// UPSERT：键冲突时更新值与时间戳
-	st := model.SiteSetting{Key: SettingKeyAccent, Value: hex}
-	return s.db.Save(&st).Error
+	return s.putValue(SettingKeyAccent, hex)
 }
 
 // TrustReviewedPublish 是否对「已有过审内容」的用户免审。
-// KV 缺行 / 空值视为开启（默认开）；仅显式写入 false/0/off/no 为关闭。
-// 不用 GORM bool default:true，避免零值省略陷阱。
 func (s *SettingService) TrustReviewedPublish() (bool, error) {
-	var st model.SiteSetting
-	err := s.db.Where("key = ?", SettingKeyTrustReviewedPublish).First(&st).Error
-	if errors.Is(err, gorm.ErrRecordNotFound) {
-		return true, nil
-	}
+	v, found, err := s.getValue(SettingKeyTrustReviewedPublish)
 	if err != nil {
 		return true, err
 	}
-	v := strings.TrimSpace(strings.ToLower(st.Value))
-	switch v {
-	case "false", "0", "off", "no":
-		return false, nil
-	default:
-		return true, nil
-	}
+	return parseBoolDefaultTrue(v, found), nil
 }
 
 // SetTrustReviewedPublish 持久化免审开关；开启时删除键以保持「缺行=默认开」语义
 func (s *SettingService) SetTrustReviewedPublish(on bool) error {
-	if on {
-		return s.db.Where("key = ?", SettingKeyTrustReviewedPublish).Delete(&model.SiteSetting{}).Error
-	}
-	st := model.SiteSetting{Key: SettingKeyTrustReviewedPublish, Value: "false"}
-	return s.db.Save(&st).Error
+	return s.setBoolDefaultTrue(SettingKeyTrustReviewedPublish, on)
+}
+
+func (s *SettingService) SetSiteName(name string) error {
+	name = strings.TrimSpace(name)
+	if name == "" || name == DefaultSiteName {
+		return s.deleteKey(SettingKeySiteName)
+	}
+	if utf8.RuneCountInString(name) > MaxSiteNameRunes {
+		return ErrInvalidSiteSetting
+	}
+	return s.putValue(SettingKeySiteName, name)
+}
+
+func (s *SettingService) SetSiteDescription(desc string) error {
+	desc = strings.TrimSpace(desc)
+	if utf8.RuneCountInString(desc) > MaxSiteDescRunes {
+		return ErrInvalidSiteSetting
+	}
+	if desc == "" || desc == DefaultSiteDescription {
+		return s.deleteKey(SettingKeySiteDescription)
+	}
+	return s.putValue(SettingKeySiteDescription, desc)
+}
+
+func (s *SettingService) AllowRegister() (bool, error) {
+	v, found, err := s.getValue(SettingKeyAllowRegister)
+	if err != nil {
+		return true, err
+	}
+	return parseBoolDefaultTrue(v, found), nil
+}
+
+func (s *SettingService) SetAllowRegister(on bool) error {
+	return s.setBoolDefaultTrue(SettingKeyAllowRegister, on)
+}
+
+// PostCooldownHours 新用户发帖冷静期（小时）。缺行=24；0 表示关闭。
+func (s *SettingService) PostCooldownHours() (int, error) {
+	v, found, err := s.getValue(SettingKeyPostCooldownHours)
+	if err != nil {
+		return DefaultCooldownHours, err
+	}
+	if !found {
+		return DefaultCooldownHours, nil
+	}
+	n, convErr := strconv.Atoi(strings.TrimSpace(v))
+	if convErr != nil || n < 0 {
+		return DefaultCooldownHours, nil
+	}
+	if n > MaxCooldownHours {
+		return MaxCooldownHours, nil
+	}
+	return n, nil
+}
+
+func (s *SettingService) SetPostCooldownHours(hours int) error {
+	if hours < 0 || hours > MaxCooldownHours {
+		return ErrInvalidSiteSetting
+	}
+	if hours == DefaultCooldownHours {
+		return s.deleteKey(SettingKeyPostCooldownHours)
+	}
+	return s.putValue(SettingKeyPostCooldownHours, strconv.Itoa(hours))
 }