comments implement

src/modules/comment/application/use-cases/list-comments/list-comments.use-case.ts

@@ -0,0 +1,33 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { COMMENT_REPOSITORY, type ICommentRepository } from '../../../domain/repositories/comment.repository.interface.js';
+import { ISSUE_REPOSITORY, type IIssueRepository } from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { ListCommentsQuery } from './list-comments.query.js';
+import { CommentDto } from '../../dto/comment.dto.js';
+import { CommentAuthorExpanderService } from '../../services/comment-author-expander.service.js';
+
+@Injectable()
+export class ListCommentsUseCase {
+  constructor(
+    @Inject(COMMENT_REPOSITORY)
+    private readonly commentRepository: ICommentRepository,
+    @Inject(ISSUE_REPOSITORY)
+    private readonly issueRepository: IIssueRepository,
+    private readonly commentAuthorExpander: CommentAuthorExpanderService,
+  ) {}
+
+  async execute(query: ListCommentsQuery): Promise<{ list: CommentDto[]; nextCursor: string | null }> {
+    const issue = await this.issueRepository.findById(query.issueId, query.userId);
+    if (!issue) {
+      throw new IssueNotFoundException(query.issueId);
+    }
+
+    const { list, nextCursor } = await this.commentRepository.findByIssue({
+      issueId: query.issueId,
+      limit: query.limit,
+      cursor: query.cursor,
+    });
+
+    return { list: await this.commentAuthorExpander.expandAll(list), nextCursor };
+  }
+}