src/main/java/com/example/myproject/service/SeedCommentService.java

package com.example.myproject.service;

import com.example.myproject.entity.SeedComment;
import com.example.myproject.entity.SeedCommentLikes;
import com.example.myproject.repository.SeedCommentLikesRepository;
import com.example.myproject.repository.SeedCommentRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.*;

@Service
public class SeedCommentService {

    @Autowired
    private SeedCommentRepository seedCommentRepository;

    @Autowired
    private SeedCommentLikesRepository seedCommentLikesRepository;

    public String publishComment(int seedId, SeedComment seedComment) {
        try {
            // 如果是回复评论，检查父评论是否存在
            if (seedComment.getComCommentId() != 0) {
                // 查找父评论是否存在
                boolean parentExists = seedCommentRepository.existsById(seedComment.getComCommentId());
                if (!parentExists) {
                    return "{ \"status\": \"error\", \"message\": \"父评论不存在\" }";
                }
            }

            // 设置评论的种子ID
            seedComment.setSeedId(seedId);
            seedComment.setCommentTime(new Date());
            seedComment.setLikesCount(0);  // 默认点赞数为0
            seedComment.setReplyCount(0);  // 默认回复数为0

            // 如果没有父评论，com_comment_id 默认为0
            if (seedComment.getComCommentId() == 0) {
                seedComment.setComCommentId(0);
            }

            // 保存评论到数据库
            seedCommentRepository.save(seedComment);

            // 返回成功信息
            return "{ \"status\": \"success\", \"message\": \"评论发布成功\" }";
        } catch (Exception e) {
            // 处理异常，返回失败信息
            return "{ \"status\": \"error\", \"message\": \"评论发布失败\" }";
        }
    }

    public Map<String, Object> getAllCommentsForSeed(int seedId) {
        // 获取该种子的所有评论（顶级评论）
        List<SeedComment> allComments = seedCommentRepository.findBySeedId(seedId);
        List<Map<String, Object>> responseComments = new ArrayList<>();

        for (SeedComment comment : allComments) {
            Map<String, Object> commentData = new HashMap<>();
            commentData.put("comment_id", comment.getCommentId());
            commentData.put("user_id", comment.getUserId());
            commentData.put("username", "User" + comment.getUserId());  // 通过用户ID查询用户名
            commentData.put("content", comment.getContent());
            commentData.put("parent_comment_id", comment.getComCommentId());

            // 获取该评论的所有回复
            List<Map<String, Object>> replies = getRepliesForComment(comment.getCommentId());
            commentData.put("replies", replies);

            responseComments.add(commentData);
        }

        // 返回最终结果
        Map<String, Object> result = new LinkedHashMap<>();
        result.put("status", "success");
        result.put("comments", responseComments);

        return result;
    }

    // 获取特定评论的所有回复
    private List<Map<String, Object>> getRepliesForComment(long parentCommentId) {
        List<SeedComment> replies = seedCommentRepository.findByComCommentId(parentCommentId);
        List<Map<String, Object>> replyResponses = new ArrayList<>();

        for (SeedComment reply : replies) {
            Map<String, Object> replyData = new LinkedHashMap<>();
            replyData.put("comment_id", reply.getCommentId());
            replyData.put("user_id", reply.getUserId());
            replyData.put("username", "User" + reply.getUserId());  // 通过用户ID查询用户名
            replyData.put("content", reply.getContent());
            replyData.put("parent_comment_id", reply.getComCommentId());
            replyResponses.add(replyData);
        }

        return replyResponses;
    }

    // 点赞切换逻辑
    public Map<String, Object> toggleLike(Long commentId, Long userId) {
        // 查找是否有该评论
        Optional<SeedComment> seedCommentOptional = seedCommentRepository.findById(commentId);
        if (!seedCommentOptional.isPresent()) {
            return Map.of("status", "error", "message", "评论不存在");
        }

        SeedComment seedComment = seedCommentOptional.get();

        // 查找该用户是否已点赞
        Optional<SeedCommentLikes> commentLikeOptional = seedCommentLikesRepository.findByCommentIdAndUserId(commentId, userId);

        // 如果用户未点赞，添加新的点赞记录
        if (commentLikeOptional.isEmpty()) {
            SeedCommentLikes newLike = new SeedCommentLikes();
            newLike.setCommentId(commentId);
            newLike.setUserId(userId);
            newLike.setIsLiked(true);

            // 更新 SeedComment 表中的点赞数
            seedComment.setLikesCount(seedComment.getLikesCount() + 1);
            seedCommentRepository.save(seedComment);

            // 保存点赞记录
            seedCommentLikesRepository.save(newLike);

            return Map.of("status", "success", "message", "操作成功", "liked", "true");
        } else {
            SeedCommentLikes commentLike = commentLikeOptional.get();

            // 如果已经点赞，取消点赞
            if (commentLike.getIsLiked()) {
                commentLike.setIsLiked(false);

                // 更新 SeedComment 表中的点赞数
                seedComment.setLikesCount(seedComment.getLikesCount() - 1);
                seedCommentRepository.save(seedComment);

                // 更新点赞记录
                seedCommentLikesRepository.save(commentLike);

                return Map.of("status", "success", "message", "操作成功", "liked", "false");
            } else {
                // 如果未点赞，进行点赞
                commentLike.setIsLiked(true);

                // 更新 SeedComment 表中的点赞数
                seedComment.setLikesCount(seedComment.getLikesCount() + 1);
                seedCommentRepository.save(seedComment);

                // 更新点赞记录
                seedCommentLikesRepository.save(commentLike);

                return Map.of("status", "success", "message", "操作成功", "liked", "true");
            }
        }
    }
}