init: 毛孩子计划小程序 + Go 后端 + 内嵌后台

- pets-fe: 微信原生小程序（首页/计划/记录/报告/社区/引导），服务端驱动、无假数据；弹层改用 scroll-view，打开时隐藏自定义 tabBar - pets-be: Gin + GORM(MySQL, sundynix_ 前缀) + MinIO，统一响应/分页，微信 code2session 登录，provider-neutral AI(DeepSeek)，go:embed React 后台 - 修复：分段选择类型不匹配（字符串 vs 数字）导致选不中 Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-07-03 15:33:31 +08:00
commit 609f7d06cf
180 changed files with 15259 additions and 0 deletions
@@ -0,0 +1,177 @@
+package service
+
+import (
+	"gorm.io/datatypes"
+	"gorm.io/gorm"
+
+	"github.com/sundynix/pets-be/internal/model"
+)
+
+// tabTag 将 feed tab 映射为标签过滤（空表示不过滤）
+func tabTag(tab string) string {
+	switch tab {
+	case "新手求助":
+		return "求助"
+	case "晒宠":
+		return "晒宠"
+	case "经验":
+		return "经验"
+	default: // 推荐 / 关注
+		return ""
+	}
+}
+
+// ListPosts 帖子分页列表
+func (s *Service) ListPosts(tab string, offset, limit int) ([]model.Post, int64, error) {
+	q := s.db.Model(&model.Post{}).Where("status = ?", model.PostPublished)
+	if tag := tabTag(tab); tag != "" {
+		q = q.Where("JSON_CONTAINS(tags, ?)", `"`+tag+`"`)
+	}
+	var total int64
+	if err := q.Count(&total).Error; err != nil {
+		return nil, 0, err
+	}
+	var posts []model.Post
+	if err := q.Order("id desc").Offset(offset).Limit(limit).Find(&posts).Error; err != nil {
+		return nil, 0, err
+	}
+	return posts, total, nil
+}
+
+// GetPost 帖子详情
+func (s *Service) GetPost(postID uint) (*model.Post, error) {
+	var p model.Post
+	if err := s.db.First(&p, postID).Error; err != nil {
+		if err == gorm.ErrRecordNotFound {
+			return nil, ErrNotFound
+		}
+		return nil, err
+	}
+	return &p, nil
+}
+
+// PostInput 发帖入参
+type PostInput struct {
+	PetID    *uint
+	Identity string
+	Content  string
+	Tags     datatypes.JSON
+	Images   datatypes.JSON
+}
+
+// CreatePost 发帖
+func (s *Service) CreatePost(userID uint, in PostInput) (*model.Post, error) {
+	authorName := "匿名宠友"
+	authorEmoji := "🐾"
+	switch in.Identity {
+	case "official":
+		authorName = "毛孩子计划官方"
+	case "petName":
+		if in.PetID != nil {
+			var pet model.Pet
+			if err := s.db.First(&pet, *in.PetID).Error; err == nil {
+				authorName = pet.Name + "的铲屎官"
+				authorEmoji = pet.Emoji
+			}
+		}
+	}
+	p := model.Post{
+		UserID: userID, PetID: in.PetID, AuthorName: authorName, AuthorEmoji: authorEmoji,
+		Identity: in.Identity, Content: in.Content, Tags: in.Tags, Images: in.Images,
+		Status: model.PostPublished,
+	}
+	if err := s.db.Create(&p).Error; err != nil {
+		return nil, err
+	}
+	return &p, nil
+}
+
+// LikePost 点赞（幂等：已赞则不重复计数）
+func (s *Service) LikePost(userID, postID uint) (int, error) {
+	if _, err := s.GetPost(postID); err != nil {
+		return 0, err
+	}
+	err := s.db.Transaction(func(tx *gorm.DB) error {
+		like := model.PostLike{PostID: postID, UserID: userID}
+		res := tx.Where("post_id = ? AND user_id = ?", postID, userID).FirstOrCreate(&like)
+		if res.Error != nil {
+			return res.Error
+		}
+		if res.RowsAffected == 1 { // 新建才计数
+			return tx.Model(&model.Post{}).Where("id = ?", postID).
+				UpdateColumn("like_count", gorm.Expr("like_count + 1")).Error
+		}
+		return nil
+	})
+	if err != nil {
+		return 0, err
+	}
+	return s.postLikeCount(postID)
+}
+
+// UnlikePost 取消点赞
+func (s *Service) UnlikePost(userID, postID uint) (int, error) {
+	if _, err := s.GetPost(postID); err != nil {
+		return 0, err
+	}
+	err := s.db.Transaction(func(tx *gorm.DB) error {
+		res := tx.Where("post_id = ? AND user_id = ?", postID, userID).Delete(&model.PostLike{})
+		if res.Error != nil {
+			return res.Error
+		}
+		if res.RowsAffected == 1 {
+			return tx.Model(&model.Post{}).Where("id = ? AND like_count > 0", postID).
+				UpdateColumn("like_count", gorm.Expr("like_count - 1")).Error
+		}
+		return nil
+	})
+	if err != nil {
+		return 0, err
+	}
+	return s.postLikeCount(postID)
+}
+
+func (s *Service) postLikeCount(postID uint) (int, error) {
+	var p model.Post
+	if err := s.db.Select("like_count").First(&p, postID).Error; err != nil {
+		return 0, err
+	}
+	return p.LikeCount, nil
+}
+
+// ListComments 评论分页
+func (s *Service) ListComments(postID uint, offset, limit int) ([]model.Comment, int64, error) {
+	q := s.db.Model(&model.Comment{}).Where("post_id = ? AND status = ?", postID, "published")
+	var total int64
+	if err := q.Count(&total).Error; err != nil {
+		return nil, 0, err
+	}
+	var comments []model.Comment
+	if err := q.Order("id desc").Offset(offset).Limit(limit).Find(&comments).Error; err != nil {
+		return nil, 0, err
+	}
+	return comments, total, nil
+}
+
+// CreateComment 评论
+func (s *Service) CreateComment(userID, postID uint, content string) (*model.Comment, error) {
+	if _, err := s.GetPost(postID); err != nil {
+		return nil, err
+	}
+	var user model.User
+	name := "宠友"
+	if err := s.db.First(&user, userID).Error; err == nil && user.Nickname != "" {
+		name = user.Nickname
+	}
+	comment := model.Comment{PostID: postID, UserID: userID, AuthorName: name, Content: content, Status: "published"}
+	if err := s.db.Transaction(func(tx *gorm.DB) error {
+		if err := tx.Create(&comment).Error; err != nil {
+			return err
+		}
+		return tx.Model(&model.Post{}).Where("id = ?", postID).
+			UpdateColumn("comment_count", gorm.Expr("comment_count + 1")).Error
+	}); err != nil {
+		return nil, err
+	}
+	return &comment, nil
+}