⚡ add like functionality with Like model, implement like/unlike methods, and update Post and Comment models to track like counts

internal/model/comment.go

@@ -4,11 +4,13 @@ import "gorm.io/gorm"
 
 type Comment struct {
 	gorm.Model
-	UserID     uint   `gorm:"index"`                           // 评论的用户ID
-	User       User   `gorm:"foreignKey:UserID;references:ID"` // 关联的用户
-	TargetID   uint   `gorm:"index"`                           // 目标ID
-	TargetType string `gorm:"index"`                           // 目标类型，如 "post", "page"
-	ReplyID    uint   `gorm:"index"`                           // 回复的评论ID
-	Content    string `gorm:"type:text"`                       // 评论内容
-	Depth      int    `gorm:"default:0"`                       // 评论的层级深度
+	UserID       uint   `gorm:"index"`                           // 评论的用户ID
+	User         User   `gorm:"foreignKey:UserID;references:ID"` // 关联的用户
+	TargetID     uint   `gorm:"index"`                           // 目标ID
+	TargetType   string `gorm:"index"`                           // 目标类型，如 "post", "page"
+	ReplyID      uint   `gorm:"index"`                           // 回复的评论ID
+	Content      string `gorm:"type:text"`                       // 评论内容
+	Depth        int    `gorm:"default:0"`                       // 评论的层级深度
+	LikeCount    uint64
+	CommentCount uint64
 }

internal/model/label.go

@@ -4,7 +4,8 @@ import "gorm.io/gorm"
 
 type Label struct {
 	gorm.Model
-	Key   string `gorm:"uniqueIndex"` // 标签键，唯一标识
-	Value string `gorm:"type:text"`   // 标签值，描述标签的内容
-	Color string `gorm:"type:text"`   // 前端可用颜色代码
+	Key               string `gorm:"uniqueIndex"` // 标签键，唯一标识
+	Value             string `gorm:"type:text"`   // 标签值，描述标签的内容
+	Color             string `gorm:"type:text"`   // 前端可用颜色代码
+	TailwindClassName string `gorm:"type:text"`   // Tailwind CSS 的类名，用于前端样式
 }

internal/model/like.go

@@ -0,0 +1,42 @@
+package model
+
+import (
+	"fmt"
+	"github.com/snowykami/neo-blog/pkg/constant"
+	"gorm.io/gorm"
+)
+
+type Like struct {
+	gorm.Model
+	TargetType string
+	TargetID   uint
+	UserID     uint
+}
+
+// AfterCreate 点赞后更新被点赞对象的计数
+func (l *Like) AfterCreate(tx *gorm.DB) (err error) {
+	switch l.TargetType {
+	case constant.TargetTypePost:
+		return tx.Model(&Post{}).Where("id = ?", l.TargetID).
+			UpdateColumn("like_count", gorm.Expr("like_count + ?", 1)).Error
+	case constant.TargetTypeComment:
+		return tx.Model(&Comment{}).Where("id = ?", l.TargetID).
+			UpdateColumn("like_count", gorm.Expr("like_count + ?", 1)).Error
+	default:
+		return fmt.Errorf("不支持的目标类型: %s", l.TargetType)
+	}
+}
+
+// AfterDelete 取消点赞后更新被点赞对象的计数
+func (l *Like) AfterDelete(tx *gorm.DB) (err error) {
+	switch l.TargetType {
+	case constant.TargetTypePost:
+		return tx.Model(&Post{}).Where("id = ?", l.TargetID).
+			UpdateColumn("like_count", gorm.Expr("GREATEST(like_count - ?, 0)", 1)).Error
+	case constant.TargetTypeComment:
+		return tx.Model(&Comment{}).Where("id = ?", l.TargetID).
+			UpdateColumn("like_count", gorm.Expr("GREATEST(like_count - ?, 0)", 1)).Error
+	default:
+		return fmt.Errorf("不支持的目标类型: %s", l.TargetType)
+	}
+}

internal/model/post.go

@@ -4,9 +4,13 @@ import "gorm.io/gorm"
 
 type Post struct {
 	gorm.Model
-	UserID  uint    `gorm:"index"`                                                                // 发布者的用户ID
-	User    User    `gorm:"foreignKey:UserID;references:ID"`                                      // 关联的用户
-	Title   string  `gorm:"type:text;not null"`                                                   // 帖子标题
-	Content string  `gorm:"type:text;not null"`                                                   // 帖子内容
-	Labels  []Label `gorm:"many2many:post_labels;constraint:OnUpdate:CASCADE,OnDelete:SET NULL;"` // 关联的标签
+	UserID       uint    `gorm:"index"`                                                                // 发布者的用户ID
+	User         User    `gorm:"foreignKey:UserID;references:ID"`                                      // 关联的用户
+	Title        string  `gorm:"type:text;not null"`                                                   // 帖子标题
+	Content      string  `gorm:"type:text;not null"`                                                   // 帖子内容
+	Labels       []Label `gorm:"many2many:post_labels;constraint:OnUpdate:CASCADE,OnDelete:SET NULL;"` // 关联的标签
+	IsPrivate    bool    `gorm:"default:false"`                                                        // 是否为私密帖子
+	LikeCount    uint64
+	CommentCount uint64
+	VisitorCount uint64
 }