SMANAGE/gvsds/apps/community/manager.py

"""模块：Community 社区数据访问层

官网社区（discuss.gvsds.com）的板块/分类/帖子/回复/点赞数据访问收敛在此，
视图层不直接操作 ORM。所有方法遵循帕斯卡命名法。
"""

import uuid

from django.db.models import Count, F

from .models import (
    CommunityBoard,
    CommunityCategory,
    CommunityLike,
    CommunityPost,
    CommunityReply,
)


class CommunityManager:
    """社区管理器"""

    # ========== 板块 / 分类 ==========

    @staticmethod
    def ListActiveBoards():
        """启用板块列表"""
        return list(CommunityBoard.objects.filter(BoardStatus=1))

    @staticmethod
    def CountPostsByBoards(BoardUUIDs):
        """各板块的已发布帖子数 {板块bytes: 帖子数}（BoardUUIDs 为空返回 {}）"""
        if not BoardUUIDs:
            return {}
        return {
            BoardUUID: PostCount
            for BoardUUID, PostCount in CommunityPost.objects.filter(
                PostStatus=1, BoardUUID__in=BoardUUIDs,
            ).values_list('BoardUUID').annotate(c=Count('PostUUID'))
        }

    @staticmethod
    def ListActiveCategories():
        """启用分类列表"""
        return list(CommunityCategory.objects.filter(CategoryStatus=1))

    @staticmethod
    def GetBoard(BoardUUID):
        """按 UUID 取板块（不存在返回 None）"""
        return CommunityBoard.objects.filter(BoardUUID=BoardUUID).first()

    @staticmethod
    def GetActiveBoard(BoardUUID):
        """按 UUID 取启用板块（不存在或已停用返回 None）"""
        return CommunityBoard.objects.filter(BoardUUID=BoardUUID, BoardStatus=1).first()

    @staticmethod
    def GetCategory(CategoryUUID):
        """按 UUID 取分类（UUID 为空返回 None）"""
        if not CategoryUUID:
            return None
        return CommunityCategory.objects.filter(CategoryUUID=CategoryUUID).first()

    # ========== 帖子 ==========

    @staticmethod
    def QueryPosts(Filters=None):
        """已发布帖子查询集

        Filters 为附加过滤条件（键为 ORM lookup、值为已转换好的 bytes/str），
        由调用方按「参数存在才过滤」的语义构造；为空表示仅限已发布。
        """
        return CommunityPost.objects.filter(PostStatus=1, **(Filters or {}))

    @staticmethod
    def GetPost(PostUUID, OnlyPublished=False):
        """按 UUID 取帖子（OnlyPublished=True 时排除已删除；不存在返回 None）"""
        qs = CommunityPost.objects.filter(PostUUID=PostUUID)
        if OnlyPublished:
            qs = qs.filter(PostStatus=1)
        return qs.first()

    @staticmethod
    def CreatePost(BoardUUID, Title, Content, AuthorUUID, AuthorName, CategoryUUID=None):
        """发帖"""
        return CommunityPost.objects.create(
            PostUUID=uuid.uuid4().bytes,
            BoardUUID=BoardUUID,
            CategoryUUID=CategoryUUID,
            Title=Title,
            Content=Content,
            AuthorUUID=AuthorUUID,
            AuthorName=AuthorName,
        )

    @staticmethod
    def IncreaseViewCount(PostUUID):
        """浏览量 +1（DB 侧原子自增）"""
        CommunityPost.objects.filter(PostUUID=PostUUID).update(ViewCount=F('ViewCount') + 1)

    @staticmethod
    def IncreaseReplyCount(PostUUID):
        """回复数 +1（DB 侧原子自增）"""
        CommunityPost.objects.filter(PostUUID=PostUUID).update(ReplyCount=F('ReplyCount') + 1)

    # ========== 回复 ==========

    @staticmethod
    def ListReplies(PostUUID):
        """帖子下未删除回复列表"""
        return CommunityReply.objects.filter(PostUUID=PostUUID, ReplyStatus=1)

    @staticmethod
    def CreateReply(PostUUID, AuthorUUID, AuthorName, Content, ReplyToUUID=None):
        """新增回复"""
        return CommunityReply.objects.create(
            ReplyUUID=uuid.uuid4().bytes,
            PostUUID=PostUUID,
            AuthorUUID=AuthorUUID,
            AuthorName=AuthorName,
            Content=Content,
            ReplyToUUID=ReplyToUUID,
        )

    # ========== 点赞 ==========

    @staticmethod
    def HasLiked(PostUUID, AuthorUUID):
        """判断用户是否已点赞该帖子"""
        return CommunityLike.objects.filter(PostUUID=PostUUID, AuthorUUID=AuthorUUID).exists()

    @staticmethod
    def ToggleLike(PostUUID, AuthorUUID):
        """切换点赞状态并同步帖子点赞数

        Returns:
            True 表示本次为点赞，False 表示本次为取消点赞
        """
        existing = CommunityLike.objects.filter(PostUUID=PostUUID, AuthorUUID=AuthorUUID).first()
        if existing is not None:
            existing.delete()
            CommunityPost.objects.filter(PostUUID=PostUUID).update(LikeCount=F('LikeCount') - 1)
            return False
        CommunityLike.objects.create(
            LikeUUID=uuid.uuid4().bytes,
            PostUUID=PostUUID,
            AuthorUUID=AuthorUUID,
        )
        CommunityPost.objects.filter(PostUUID=PostUUID).update(LikeCount=F('LikeCount') + 1)
        return True