feat: 添加每日签到功能，新增帖子排序与社区面板优化

本次提交完成了多个核心功能迭代： 1. 新增用户每日签到系统，包含签到状态查询、连续天数统计、积分累计逻辑 2. 新增"新帖子"排序选项，替换原有的latest排序为新评论排序 3. 重构首页信息流布局，优化移动端与桌面端展示样式 4. 新增最新评论、最新注册用户模块，完善社区面板数据展示 5. 新增静态友情链接配置模块 6. 提取通用时间格式化工具函数，统一全站相对时间展示 7. 补充数据库签到模型与后端API接口，完善前后端交互链路
2026-09-13 06:03:40 +08:00
parent 95921d24fa
commit 9bae6f2513
19 changed files with 790 additions and 280 deletions
--- a/backend/service/checkin.go
+++ b/backend/service/checkin.go
@@ -0,0 +1,136 @@
+package service
+
+import (
+	"errors"
+	"time"
+
+	"github.com/freefire/jiang13-bbs/model"
+	"gorm.io/gorm"
+)
+
+// DailyCheckinPoints 每日签到固定积分
+const DailyCheckinPoints = 5
+
+// maxStreakScan 连续天数最多向前回溯的天数
+const maxStreakScan = 400
+
+// ErrAlreadyCheckedIn 今日已签到
+var ErrAlreadyCheckedIn = errors.New("今日已签到")
+
+// CheckinStatus 签到状态（首页右栏与签到接口共用）
+type CheckinStatus struct {
+	CheckedToday bool `json:"checked_today"`
+	Streak       int  `json:"streak"`        // 连续签到天数
+	TotalPoints  int  `json:"total_points"`  // 累计积分（签到所得）
+	TodayPoints  int  `json:"today_points"`  // 今日签到可得积分
+}
+
+// CheckinService 每日签到
+type CheckinService struct {
+	db *gorm.DB
+}
+
+func NewCheckinService(db *gorm.DB) *CheckinService {
+	return &CheckinService{db: db}
+}
+
+// localDay 取本地时区零点日期
+func localDay(t time.Time) time.Time {
+	y, m, d := t.Date()
+	return time.Date(y, m, d, 0, 0, 0, 0, t.Location())
+}
+
+// streakFrom 从 anchor（含）起按日倒推连续签到天数
+func streakFrom(dates map[string]bool, anchor time.Time) int {
+	streak := 0
+	for i := 0; i < maxStreakScan; i++ {
+		day := anchor.AddDate(0, 0, -i)
+		if !dates[day.Format("2006-01-02")] {
+			break
+		}
+		streak++
+	}
+	return streak
+}
+
+// Status 查询用户签到状态
+func (s *CheckinService) Status(userID uint) (*CheckinStatus, error) {
+	today := localDay(time.Now())
+
+	var todayRow model.Checkin
+	err := s.db.Where("user_id = ? AND checkin_date::date = ?::date", userID, today).
+		First(&todayRow).Error
+	checkedToday := true
+	if err != nil {
+		if !errors.Is(err, gorm.ErrRecordNotFound) {
+			return nil, err
+		}
+		checkedToday = false
+	}
+
+	// 连续天数：今日已签从今天起算，未签从昨天起算（今日尚未签不打断连续）
+	anchor := today
+	if !checkedToday {
+		anchor = today.AddDate(0, 0, -1)
+	}
+	var dates []time.Time
+	if err := s.db.Model(&model.Checkin{}).
+		Where("user_id = ? AND checkin_date >= ?", userID, anchor.AddDate(0, 0, -maxStreakScan)).
+		Pluck("checkin_date", &dates).Error; err != nil {
+		return nil, err
+	}
+	dateSet := make(map[string]bool, len(dates))
+	for _, d := range dates {
+		dateSet[localDay(d).Format("2006-01-02")] = true
+	}
+
+	var total int64
+	if err := s.db.Model(&model.Checkin{}).
+		Where("user_id = ?", userID).
+		Select("COALESCE(SUM(points), 0)").Scan(&total).Error; err != nil {
+		return nil, err
+	}
+
+	return &CheckinStatus{
+		CheckedToday: checkedToday,
+		Streak:       streakFrom(dateSet, anchor),
+		TotalPoints:  int(total),
+		TodayPoints:  DailyCheckinPoints,
+	}, nil
+}
+
+// CheckIn 执行今日签到（每日一条，唯一索引兜底并发）
+func (s *CheckinService) CheckIn(userID uint) (*CheckinStatus, error) {
+	today := localDay(time.Now())
+
+	var status *CheckinStatus
+	err := s.db.Transaction(func(tx *gorm.DB) error {
+		var count int64
+		if err := tx.Model(&model.Checkin{}).
+			Where("user_id = ? AND checkin_date::date = ?::date", userID, today).
+			Count(&count).Error; err != nil {
+			return err
+		}
+		if count > 0 {
+			return ErrAlreadyCheckedIn
+		}
+		row := model.Checkin{
+			UserID:      userID,
+			CheckinDate: today,
+			Points:      DailyCheckinPoints,
+		}
+		if err := tx.Create(&row).Error; err != nil {
+			return err
+		}
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	status, err = s.Status(userID)
+	if err != nil {
+		return nil, err
+	}
+	return status, nil
+}