diff --git a/backend/go-service/app/constants/contact.go b/backend/go-service/app/constants/contact.go
new file mode 100644
index 0000000..a793270
--- /dev/null
+++ b/backend/go-service/app/constants/contact.go
@@ -0,0 +1,8 @@
+package constants
+
+const (
+	FriendshipStatusPending  = 0 // 待确认（已发送申请）
+	FriendshipStatusAccepted = 1 // 已接受（互为好友）
+	FriendshipStatusRejected = 2 // 已拒绝
+	FriendshipStatusBlocked  = 3 // 已拉黑
+)
diff --git a/backend/go-service/app/contact/dao/friend_group_dao.go b/backend/go-service/app/contact/dao/friend_group_dao.go
new file mode 100644
index 0000000..8550845
--- /dev/null
+++ b/backend/go-service/app/contact/dao/friend_group_dao.go
@@ -0,0 +1,116 @@
+package dao
+
+import (
+	"context"
+
+	"github.com/echochat/backend/app/contact/model"
+	"github.com/echochat/backend/pkg/logs"
+	"go.uber.org/zap"
+	"gorm.io/gorm"
+)
+
+// FriendGroupDAO 好友分组数据访问对象
+type FriendGroupDAO struct {
+	db *gorm.DB
+}
+
+// NewFriendGroupDAO 创建 FriendGroupDAO 实例
+func NewFriendGroupDAO(db *gorm.DB) *FriendGroupDAO {
+	return &FriendGroupDAO{db: db}
+}
+
+// CreateGroup 创建好友分组
+func (d *FriendGroupDAO) CreateGroup(ctx context.Context, userID int64, name string) (*model.FriendGroup, error) {
+	funcName := "dao.friend_group_dao.CreateGroup"
+	logs.Info(ctx, funcName, "创建好友分组",
+		zap.Int64("user_id", userID), zap.String("name", name))
+
+	group := &model.FriendGroup{
+		UserID: userID,
+		Name:   name,
+	}
+	err := d.db.WithContext(ctx).Create(group).Error
+	if err != nil {
+		logs.Error(ctx, funcName, "创建分组失败", zap.Error(err))
+	}
+	return group, err
+}
+
+// GetGroups 获取用户的所有好友分组
+func (d *FriendGroupDAO) GetGroups(ctx context.Context, userID int64) ([]model.FriendGroup, error) {
+	funcName := "dao.friend_group_dao.GetGroups"
+	logs.Debug(ctx, funcName, "查询好友分组", zap.Int64("user_id", userID))
+
+	var groups []model.FriendGroup
+	err := d.db.WithContext(ctx).
+		Where("user_id = ?", userID).
+		Order("sort_order ASC, id ASC").
+		Find(&groups).Error
+	return groups, err
+}
+
+// UpdateGroup 更新分组信息
+func (d *FriendGroupDAO) UpdateGroup(ctx context.Context, groupID int64, userID int64, name string, sortOrder *int) error {
+	funcName := "dao.friend_group_dao.UpdateGroup"
+	logs.Info(ctx, funcName, "更新好友分组",
+		zap.Int64("group_id", groupID), zap.String("name", name))
+
+	updates := map[string]interface{}{"name": name}
+	if sortOrder != nil {
+		updates["sort_order"] = *sortOrder
+	}
+
+	result := d.db.WithContext(ctx).
+		Model(&model.FriendGroup{}).
+		Where("id = ? AND user_id = ?", groupID, userID).
+		Updates(updates)
+
+	if result.Error != nil {
+		return result.Error
+	}
+	if result.RowsAffected == 0 {
+		return gorm.ErrRecordNotFound
+	}
+	return nil
+}
+
+// DeleteGroup 删除分组（同时将该分组下的好友移出分组）
+func (d *FriendGroupDAO) DeleteGroup(ctx context.Context, groupID int64, userID int64) error {
+	funcName := "dao.friend_group_dao.DeleteGroup"
+	logs.Info(ctx, funcName, "删除好友分组",
+		zap.Int64("group_id", groupID), zap.Int64("user_id", userID))
+
+	return d.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		tx.Model(&model.Friendship{}).
+			Where("user_id = ? AND group_id = ?", userID, groupID).
+			Update("group_id", nil)
+
+		result := tx.Where("id = ? AND user_id = ?", groupID, userID).
+			Delete(&model.FriendGroup{})
+		if result.RowsAffected == 0 {
+			return gorm.ErrRecordNotFound
+		}
+		return result.Error
+	})
+}
+
+// MoveToGroup 移动好友到指定分组
+func (d *FriendGroupDAO) MoveToGroup(ctx context.Context, userID, friendID int64, groupID *int64) error {
+	funcName := "dao.friend_group_dao.MoveToGroup"
+	logs.Info(ctx, funcName, "移动好友到分组",
+		zap.Int64("user_id", userID), zap.Int64("friend_id", friendID))
+
+	return d.db.WithContext(ctx).
+		Model(&model.Friendship{}).
+		Where("user_id = ? AND friend_id = ? AND status = 1", userID, friendID).
+		Update("group_id", groupID).Error
+}
+
+// GetGroupByID 根据 ID 获取分组
+func (d *FriendGroupDAO) GetGroupByID(ctx context.Context, groupID, userID int64) (*model.FriendGroup, error) {
+	var group model.FriendGroup
+	err := d.db.WithContext(ctx).
+		Where("id = ? AND user_id = ?", groupID, userID).
+		First(&group).Error
+	return &group, err
+}
diff --git a/backend/go-service/app/contact/dao/friendship_dao.go b/backend/go-service/app/contact/dao/friendship_dao.go
new file mode 100644
index 0000000..3d22d6b
--- /dev/null
+++ b/backend/go-service/app/contact/dao/friendship_dao.go
@@ -0,0 +1,346 @@
+// Package dao 提供 contact 模块的数据库访问操作
+package dao
+
+import (
+	"context"
+	"time"
+
+	authModel "github.com/echochat/backend/app/auth/model"
+	"github.com/echochat/backend/app/constants"
+	"github.com/echochat/backend/app/contact/model"
+	"github.com/echochat/backend/pkg/logs"
+	"go.uber.org/zap"
+	"gorm.io/gorm"
+)
+
+// FriendshipDAO 好友关系数据访问对象
+type FriendshipDAO struct {
+	db *gorm.DB
+}
+
+// NewFriendshipDAO 创建 FriendshipDAO 实例
+func NewFriendshipDAO(db *gorm.DB) *FriendshipDAO {
+	return &FriendshipDAO{db: db}
+}
+
+// CreateRequest 创建好友申请（单向 A→B，status=0）
+func (d *FriendshipDAO) CreateRequest(ctx context.Context, userID, friendID int64, message string) (*model.Friendship, error) {
+	funcName := "dao.friendship_dao.CreateRequest"
+	logs.Info(ctx, funcName, "创建好友申请",
+		zap.Int64("user_id", userID), zap.Int64("friend_id", friendID))
+
+	f := &model.Friendship{
+		UserID:   userID,
+		FriendID: friendID,
+		Status:   constants.FriendshipStatusPending,
+		Message:  message,
+	}
+	err := d.db.WithContext(ctx).Create(f).Error
+	if err != nil {
+		logs.Error(ctx, funcName, "创建好友申请失败", zap.Error(err))
+	}
+	return f, err
+}
+
+// AcceptRequest 接受好友申请（事务内：更新 A→B 为 accepted + 创建 B→A）
+func (d *FriendshipDAO) AcceptRequest(ctx context.Context, requestID, userID int64) error {
+	funcName := "dao.friendship_dao.AcceptRequest"
+	logs.Info(ctx, funcName, "接受好友申请",
+		zap.Int64("request_id", requestID), zap.Int64("user_id", userID))
+
+	return d.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		var req model.Friendship
+		if err := tx.First(&req, requestID).Error; err != nil {
+			return err
+		}
+		if req.FriendID != userID {
+			return gorm.ErrRecordNotFound
+		}
+
+		now := time.Now()
+		if err := tx.Model(&req).Updates(map[string]interface{}{
+			"status":     constants.FriendshipStatusAccepted,
+			"updated_at": now,
+		}).Error; err != nil {
+			return err
+		}
+
+		reverse := &model.Friendship{
+			UserID:   userID,
+			FriendID: req.UserID,
+			Status:   constants.FriendshipStatusAccepted,
+		}
+		return tx.Create(reverse).Error
+	})
+}
+
+// RejectRequest 拒绝好友申请
+func (d *FriendshipDAO) RejectRequest(ctx context.Context, requestID, userID int64) error {
+	funcName := "dao.friendship_dao.RejectRequest"
+	logs.Info(ctx, funcName, "拒绝好友申请",
+		zap.Int64("request_id", requestID), zap.Int64("user_id", userID))
+
+	result := d.db.WithContext(ctx).
+		Model(&model.Friendship{}).
+		Where("id = ? AND friend_id = ? AND status = ?", requestID, userID, constants.FriendshipStatusPending).
+		Update("status", constants.FriendshipStatusRejected)
+
+	if result.Error != nil {
+		return result.Error
+	}
+	if result.RowsAffected == 0 {
+		return gorm.ErrRecordNotFound
+	}
+	return nil
+}
+
+// GetFriendList 获取好友列表（status=1 的记录，JOIN 用户表获取详情）
+func (d *FriendshipDAO) GetFriendList(ctx context.Context, userID int64, groupID *int64) ([]FriendWithUser, error) {
+	funcName := "dao.friendship_dao.GetFriendList"
+	logs.Debug(ctx, funcName, "查询好友列表", zap.Int64("user_id", userID))
+
+	var results []FriendWithUser
+	query := d.db.WithContext(ctx).
+		Table("contact_friendships f").
+		Select("f.id, f.friend_id as user_id, u.username, u.nickname, u.avatar, f.remark, f.group_id, f.created_at").
+		Joins("JOIN auth_users u ON u.id = f.friend_id").
+		Where("f.user_id = ? AND f.status = ?", userID, constants.FriendshipStatusAccepted)
+
+	if groupID != nil {
+		query = query.Where("f.group_id = ?", *groupID)
+	}
+
+	err := query.Order("u.nickname ASC").Scan(&results).Error
+	if err != nil {
+		logs.Error(ctx, funcName, "查询好友列表失败", zap.Error(err))
+	}
+	return results, err
+}
+
+// FriendWithUser 好友列表查询结果（JOIN 用户表）
+type FriendWithUser struct {
+	ID        int64     `json:"id"`
+	UserID    int64     `json:"user_id"`
+	Username  string    `json:"username"`
+	Nickname  string    `json:"nickname"`
+	Avatar    string    `json:"avatar"`
+	Remark    string    `json:"remark"`
+	GroupID   *int64    `json:"group_id"`
+	CreatedAt time.Time `json:"created_at"`
+}
+
+// GetPendingRequests 获取收到的待处理好友申请
+func (d *FriendshipDAO) GetPendingRequests(ctx context.Context, userID int64) ([]RequestWithUser, error) {
+	funcName := "dao.friendship_dao.GetPendingRequests"
+	logs.Debug(ctx, funcName, "查询待处理申请", zap.Int64("user_id", userID))
+
+	var results []RequestWithUser
+	err := d.db.WithContext(ctx).
+		Table("contact_friendships f").
+		Select("f.id, f.user_id, u.username, u.nickname, u.avatar, f.message, f.status, f.created_at").
+		Joins("JOIN auth_users u ON u.id = f.user_id").
+		Where("f.friend_id = ? AND f.status = ?", userID, constants.FriendshipStatusPending).
+		Order("f.created_at DESC").
+		Scan(&results).Error
+
+	if err != nil {
+		logs.Error(ctx, funcName, "查询待处理申请失败", zap.Error(err))
+	}
+	return results, err
+}
+
+// RequestWithUser 好友申请查询结果（JOIN 申请方用户表）
+type RequestWithUser struct {
+	ID        int64     `json:"id"`
+	UserID    int64     `json:"user_id"`
+	Username  string    `json:"username"`
+	Nickname  string    `json:"nickname"`
+	Avatar    string    `json:"avatar"`
+	Message   string    `json:"message"`
+	Status    int       `json:"status"`
+	CreatedAt time.Time `json:"created_at"`
+}
+
+// DeleteFriend 删除好友（事务内双向删除）
+func (d *FriendshipDAO) DeleteFriend(ctx context.Context, userID, friendID int64) error {
+	funcName := "dao.friendship_dao.DeleteFriend"
+	logs.Info(ctx, funcName, "删除好友",
+		zap.Int64("user_id", userID), zap.Int64("friend_id", friendID))
+
+	return d.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		if err := tx.Where("user_id = ? AND friend_id = ?", userID, friendID).
+			Delete(&model.Friendship{}).Error; err != nil {
+			return err
+		}
+		return tx.Where("user_id = ? AND friend_id = ?", friendID, userID).
+			Delete(&model.Friendship{}).Error
+	})
+}
+
+// UpdateRemark 设置好友备注
+func (d *FriendshipDAO) UpdateRemark(ctx context.Context, userID, friendID int64, remark string) error {
+	funcName := "dao.friendship_dao.UpdateRemark"
+	logs.Info(ctx, funcName, "更新好友备注",
+		zap.Int64("user_id", userID), zap.Int64("friend_id", friendID))
+
+	return d.db.WithContext(ctx).
+		Model(&model.Friendship{}).
+		Where("user_id = ? AND friend_id = ? AND status = ?", userID, friendID, constants.FriendshipStatusAccepted).
+		Update("remark", remark).Error
+}
+
+// BlockUser 拉黑用户（事务内：删除双向好友 + 创建单向拉黑记录）
+func (d *FriendshipDAO) BlockUser(ctx context.Context, userID, targetID int64) error {
+	funcName := "dao.friendship_dao.BlockUser"
+	logs.Info(ctx, funcName, "拉黑用户",
+		zap.Int64("user_id", userID), zap.Int64("target_id", targetID))
+
+	return d.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		tx.Where("(user_id = ? AND friend_id = ?) OR (user_id = ? AND friend_id = ?)",
+			userID, targetID, targetID, userID).
+			Delete(&model.Friendship{})
+
+		block := &model.Friendship{
+			UserID:   userID,
+			FriendID: targetID,
+			Status:   constants.FriendshipStatusBlocked,
+		}
+		return tx.Create(block).Error
+	})
+}
+
+// UnblockUser 取消拉黑
+func (d *FriendshipDAO) UnblockUser(ctx context.Context, userID, targetID int64) error {
+	funcName := "dao.friendship_dao.UnblockUser"
+	logs.Info(ctx, funcName, "取消拉黑",
+		zap.Int64("user_id", userID), zap.Int64("target_id", targetID))
+
+	return d.db.WithContext(ctx).
+		Where("user_id = ? AND friend_id = ? AND status = ?", userID, targetID, constants.FriendshipStatusBlocked).
+		Delete(&model.Friendship{}).Error
+}
+
+// GetBlockList 获取黑名单列表
+func (d *FriendshipDAO) GetBlockList(ctx context.Context, userID int64) ([]FriendWithUser, error) {
+	funcName := "dao.friendship_dao.GetBlockList"
+	logs.Debug(ctx, funcName, "查询黑名单", zap.Int64("user_id", userID))
+
+	var results []FriendWithUser
+	err := d.db.WithContext(ctx).
+		Table("contact_friendships f").
+		Select("f.id, f.friend_id as user_id, u.username, u.nickname, u.avatar, f.remark, f.group_id, f.created_at").
+		Joins("JOIN auth_users u ON u.id = f.friend_id").
+		Where("f.user_id = ? AND f.status = ?", userID, constants.FriendshipStatusBlocked).
+		Scan(&results).Error
+	return results, err
+}
+
+// IsBlocked 检查 userID 是否被 targetID 拉黑
+func (d *FriendshipDAO) IsBlocked(ctx context.Context, userID, targetID int64) (bool, error) {
+	var count int64
+	err := d.db.WithContext(ctx).
+		Model(&model.Friendship{}).
+		Where("user_id = ? AND friend_id = ? AND status = ?", targetID, userID, constants.FriendshipStatusBlocked).
+		Count(&count).Error
+	return count > 0, err
+}
+
+// IsFriend 检查是否互为好友
+func (d *FriendshipDAO) IsFriend(ctx context.Context, userID, friendID int64) (bool, error) {
+	var count int64
+	err := d.db.WithContext(ctx).
+		Model(&model.Friendship{}).
+		Where("user_id = ? AND friend_id = ? AND status = ?", userID, friendID, constants.FriendshipStatusAccepted).
+		Count(&count).Error
+	return count > 0, err
+}
+
+// HasPendingRequest 检查是否已有待处理的申请（A→B 或 B→A）
+func (d *FriendshipDAO) HasPendingRequest(ctx context.Context, userID, friendID int64) (bool, error) {
+	var count int64
+	err := d.db.WithContext(ctx).
+		Model(&model.Friendship{}).
+		Where("((user_id = ? AND friend_id = ?) OR (user_id = ? AND friend_id = ?)) AND status = ?",
+			userID, friendID, friendID, userID, constants.FriendshipStatusPending).
+		Count(&count).Error
+	return count > 0, err
+}
+
+// GetRequestByID 根据 ID 获取好友申请
+func (d *FriendshipDAO) GetRequestByID(ctx context.Context, id int64) (*model.Friendship, error) {
+	var f model.Friendship
+	err := d.db.WithContext(ctx).First(&f, id).Error
+	return &f, err
+}
+
+// GetCommonFriends 获取共同好友 ID 列表
+func (d *FriendshipDAO) GetCommonFriends(ctx context.Context, userID, targetID int64) ([]int64, error) {
+	funcName := "dao.friendship_dao.GetCommonFriends"
+	logs.Debug(ctx, funcName, "查询共同好友",
+		zap.Int64("user_id", userID), zap.Int64("target_id", targetID))
+
+	var ids []int64
+	err := d.db.WithContext(ctx).
+		Raw(`SELECT a.friend_id FROM contact_friendships a
+			 JOIN contact_friendships b ON a.friend_id = b.friend_id
+			 WHERE a.user_id = ? AND a.status = ? AND b.user_id = ? AND b.status = ?`,
+			userID, constants.FriendshipStatusAccepted, targetID, constants.FriendshipStatusAccepted).
+		Scan(&ids).Error
+	return ids, err
+}
+
+// SearchUsers 搜索用户（按用户名或昵称模糊匹配，排除自己）
+func (d *FriendshipDAO) SearchUsers(ctx context.Context, keyword string, excludeUserID int64, page, pageSize int) ([]authModel.User, int64, error) {
+	funcName := "dao.friendship_dao.SearchUsers"
+	logs.Debug(ctx, funcName, "搜索用户", zap.String("keyword", keyword))
+
+	var users []authModel.User
+	var total int64
+
+	query := d.db.WithContext(ctx).
+		Model(&authModel.User{}).
+		Where("id != ? AND status = 1 AND (username LIKE ? OR nickname LIKE ?)",
+			excludeUserID, "%"+keyword+"%", "%"+keyword+"%")
+
+	if err := query.Count(&total).Error; err != nil {
+		return nil, 0, err
+	}
+
+	offset := (page - 1) * pageSize
+	err := query.Select("id, username, nickname, avatar").
+		Offset(offset).Limit(pageSize).
+		Find(&users).Error
+
+	return users, total, err
+}
+
+// GetFriendIDs 获取用户的所有好友 ID 列表
+func (d *FriendshipDAO) GetFriendIDs(ctx context.Context, userID int64) ([]int64, error) {
+	var ids []int64
+	err := d.db.WithContext(ctx).
+		Model(&model.Friendship{}).
+		Where("user_id = ? AND status = ?", userID, constants.FriendshipStatusAccepted).
+		Pluck("friend_id", &ids).Error
+	return ids, err
+}
+
+// CountFriendsByGroup 统计每个分组的好友数
+func (d *FriendshipDAO) CountFriendsByGroup(ctx context.Context, userID int64) (map[int64]int, error) {
+	type GroupCount struct {
+		GroupID int64 `gorm:"column:group_id"`
+		Count   int   `gorm:"column:cnt"`
+	}
+	var counts []GroupCount
+	err := d.db.WithContext(ctx).
+		Model(&model.Friendship{}).
+		Select("group_id, COUNT(*) as cnt").
+		Where("user_id = ? AND status = ? AND group_id IS NOT NULL", userID, constants.FriendshipStatusAccepted).
+		Group("group_id").
+		Scan(&counts).Error
+
+	result := make(map[int64]int)
+	for _, c := range counts {
+		result[c.GroupID] = c.Count
+	}
+	return result, err
+}
diff --git a/backend/go-service/app/contact/model/friend_group.go b/backend/go-service/app/contact/model/friend_group.go
new file mode 100644
index 0000000..edba41a
--- /dev/null
+++ b/backend/go-service/app/contact/model/friend_group.go
@@ -0,0 +1,16 @@
+package model
+
+import "time"
+
+// FriendGroup 好友分组模型，对应 contact_groups 表
+type FriendGroup struct {
+	ID        int64     `gorm:"primaryKey;autoIncrement" json:"id"`         // 分组唯一标识
+	UserID    int64     `gorm:"not null;index:idx_contact_groups_user" json:"user_id"` // 所属用户 ID
+	Name      string    `gorm:"size:50;not null" json:"name"`               // 分组名称
+	SortOrder int       `gorm:"not null;default:0" json:"sort_order"`       // 排序权重，越小越靠前
+	CreatedAt time.Time `gorm:"not null;autoCreateTime" json:"created_at"`  // 创建时间
+}
+
+func (FriendGroup) TableName() string {
+	return "contact_groups"
+}
diff --git a/backend/go-service/app/contact/model/friendship.go b/backend/go-service/app/contact/model/friendship.go
new file mode 100644
index 0000000..cdf7240
--- /dev/null
+++ b/backend/go-service/app/contact/model/friendship.go
@@ -0,0 +1,21 @@
+package model
+
+import "time"
+
+// Friendship 好友关系模型，对应 contact_friendships 表
+// 双向存储：A→B 和 B→A 各一条记录
+type Friendship struct {
+	ID        int64     `gorm:"primaryKey;autoIncrement" json:"id"`              // 记录唯一标识
+	UserID    int64     `gorm:"not null;index:idx_friendships_user_status" json:"user_id"`   // 发起方用户 ID
+	FriendID  int64     `gorm:"not null;index:idx_friendships_friend_status" json:"friend_id"` // 好友用户 ID
+	Remark    string    `gorm:"size:50;default:''" json:"remark"`                // 好友备注名
+	GroupID   *int64    `gorm:"default:null" json:"group_id"`                    // 所属好友分组 ID
+	Status    int       `gorm:"not null;default:0;index:idx_friendships_user_status" json:"status"` // 状态：0=待确认，1=已接受，2=已拒绝，3=已拉黑
+	Message   string    `gorm:"size:200;default:''" json:"message"`              // 好友申请附言
+	CreatedAt time.Time `gorm:"not null;autoCreateTime" json:"created_at"`       // 创建时间
+	UpdatedAt time.Time `gorm:"not null;autoUpdateTime" json:"updated_at"`       // 更新时间
+}
+
+func (Friendship) TableName() string {
+	return "contact_friendships"
+}
diff --git a/backend/go-service/app/dto/contact_dto.go b/backend/go-service/app/dto/contact_dto.go
new file mode 100644
index 0000000..af0542d
--- /dev/null
+++ b/backend/go-service/app/dto/contact_dto.go
@@ -0,0 +1,87 @@
+package dto
+
+// SendFriendRequestReq 发送好友申请请求
+type SendFriendRequestReq struct {
+	TargetID int64  `json:"target_id" binding:"required"` // 目标用户 ID
+	Message  string `json:"message"`                       // 申请附言
+}
+
+// HandleFriendRequestReq 处理好友申请请求
+type HandleFriendRequestReq struct {
+	RequestID int64 `json:"request_id" binding:"required"` // 申请记录 ID
+}
+
+// UpdateRemarkReq 更新好友备注请求
+type UpdateRemarkReq struct {
+	Remark string `json:"remark" binding:"max=50"` // 备注名
+}
+
+// MoveToGroupReq 移动好友到分组请求
+type MoveToGroupReq struct {
+	GroupID *int64 `json:"group_id"` // 目标分组 ID，nil 表示移出分组
+}
+
+// BlockUserReq 拉黑用户请求
+type BlockUserReq struct {
+	TargetID int64 `json:"target_id" binding:"required"` // 目标用户 ID
+}
+
+// CreateGroupReq 创建好友分组请求
+type CreateGroupReq struct {
+	Name string `json:"name" binding:"required,max=50"` // 分组名称
+}
+
+// UpdateGroupReq 修改好友分组请求
+type UpdateGroupReq struct {
+	Name      string `json:"name" binding:"required,max=50"` // 分组名称
+	SortOrder *int   `json:"sort_order"`                      // 排序权重
+}
+
+// SearchUsersReq 搜索用户请求
+type SearchUsersReq struct {
+	Keyword  string `form:"keyword" binding:"required,min=1"` // 搜索关键词
+	Page     int    `form:"page" binding:"min=1"`             // 页码
+	PageSize int    `form:"page_size" binding:"min=1,max=50"` // 每页数量
+}
+
+// FriendInfo 好友信息（列表展示用）
+type FriendInfo struct {
+	ID        int64  `json:"id"`                   // friendship 记录 ID
+	UserID    int64  `json:"user_id"`              // 好友用户 ID
+	Username  string `json:"username"`             // 用户名
+	Nickname  string `json:"nickname"`             // 昵称
+	Avatar    string `json:"avatar"`               // 头像
+	Remark    string `json:"remark"`               // 备注名
+	GroupID   *int64 `json:"group_id"`             // 所属分组
+	IsOnline  bool   `json:"is_online"`            // 是否在线
+	CreatedAt string `json:"created_at"`           // 成为好友时间
+}
+
+// FriendRequestInfo 好友申请信息
+type FriendRequestInfo struct {
+	ID        int64  `json:"id"`          // 申请记录 ID
+	UserID    int64  `json:"user_id"`     // 申请方用户 ID
+	Username  string `json:"username"`    // 申请方用户名
+	Nickname  string `json:"nickname"`    // 申请方昵称
+	Avatar    string `json:"avatar"`      // 申请方头像
+	Message   string `json:"message"`     // 申请附言
+	Status    int    `json:"status"`      // 状态
+	CreatedAt string `json:"created_at"`  // 申请时间
+}
+
+// GroupInfo 好友分组信息
+type GroupInfo struct {
+	ID          int64  `json:"id"`           // 分组 ID
+	Name        string `json:"name"`         // 分组名称
+	SortOrder   int    `json:"sort_order"`   // 排序权重
+	FriendCount int    `json:"friend_count"` // 分组内好友数
+}
+
+// SearchUserInfo 搜索结果用户信息
+type SearchUserInfo struct {
+	ID       int64  `json:"id"`        // 用户 ID
+	Username string `json:"username"`  // 用户名
+	Nickname string `json:"nickname"`  // 昵称
+	Avatar   string `json:"avatar"`    // 头像
+	IsFriend bool   `json:"is_friend"` // 是否已是好友
+}