fix: Remote Note Cleaning will delete notes embedded in a page (#16408)

* feat: preserve number of pages referencing the note

* chore: delete pages on account delete

* fix: notes on the pages are removed by CleanRemoteNotes

* test: add the simplest test for page embedded notes

* fix: section block is not considered

* fix: section block is not considered in migration

* chore: remove comments from columns

* revert unnecessary change

* add pageCount to webhook test

* fix type error on backend

1 files changed, 223 insertions, 0 deletions

diff --git a/packages/backend/src/core/PageService.ts b/packages/backend/src/core/PageService.ts
new file mode 100644
index 0000000000..7f0e5c7ccc
--- /dev/null
+++ b/packages/backend/src/core/PageService.ts
@@ -0,0 +1,223 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { Inject, Injectable } from '@nestjs/common';
+import { DataSource, In, Not } from 'typeorm';
+import { DI } from '@/di-symbols.js';
+import {
+	type NotesRepository,
+	MiPage,
+	type PagesRepository,
+	MiDriveFile,
+	type UsersRepository,
+	MiNote,
+} from '@/models/_.js';
+import { bindThis } from '@/decorators.js';
+import { RoleService } from '@/core/RoleService.js';
+import { IdService } from '@/core/IdService.js';
+import type { MiUser } from '@/models/User.js';
+import { IdentifiableError } from '@/misc/identifiable-error.js';
+import { ModerationLogService } from '@/core/ModerationLogService.js';
+
+export interface PageBody {
+	title: string;
+	name: string;
+	summary: string | null;
+	content: Array<Record<string, any>>;
+	variables: Array<Record<string, any>>;
+	script: string;
+	eyeCatchingImage?: MiDriveFile | null;
+	font: string;
+	alignCenter: boolean;
+	hideTitleWhenPinned: boolean;
+}
+
+@Injectable()
+export class PageService {
+	constructor(
+		@Inject(DI.db)
+		private db: DataSource,
+
+		@Inject(DI.pagesRepository)
+		private pagesRepository: PagesRepository,
+
+		@Inject(DI.notesRepository)
+		private notesRepository: NotesRepository,
+
+		@Inject(DI.usersRepository)
+		private usersRepository: UsersRepository,
+
+		private roleService: RoleService,
+		private moderationLogService: ModerationLogService,
+		private idService: IdService,
+	) {
+	}
+
+	@bindThis
+	public async create(
+		me: MiUser,
+		body: PageBody,
+	): Promise<MiPage> {
+		await this.pagesRepository.findBy({
+			userId: me.id,
+			name: body.name,
+		}).then(result => {
+			if (result.length > 0) {
+				throw new IdentifiableError('1a79e38e-3d83-4423-845b-a9d83ff93b61');
+			}
+		});
+
+		const page = await this.pagesRepository.insertOne(new MiPage({
+			id: this.idService.gen(),
+			updatedAt: new Date(),
+			title: body.title,
+			name: body.name,
+			summary: body.summary,
+			content: body.content,
+			variables: body.variables,
+			script: body.script,
+			eyeCatchingImageId: body.eyeCatchingImage ? body.eyeCatchingImage.id : null,
+			userId: me.id,
+			visibility: 'public',
+			alignCenter: body.alignCenter,
+			hideTitleWhenPinned: body.hideTitleWhenPinned,
+			font: body.font,
+		}));
+
+		const referencedNotes = this.collectReferencedNotes(page.content);
+		if (referencedNotes.length > 0) {
+			await this.notesRepository.increment({ id: In(referencedNotes) }, 'pageCount', 1);
+		}
+
+		return page;
+	}
+
+	@bindThis
+	public async update(
+		me: MiUser,
+		pageId: MiPage['id'],
+		body: Partial<PageBody>,
+	): Promise<void> {
+		await this.db.transaction(async (transaction) => {
+			const page = await transaction.findOne(MiPage, {
+				where: {
+					id: pageId,
+				},
+				lock: { mode: 'for_no_key_update' },
+			});
+
+			if (page == null) {
+				throw new IdentifiableError('66aefd3c-fdb2-4a71-85ae-cc18bea85d3f');
+			}
+			if (page.userId !== me.id) {
+				throw new IdentifiableError('d0017699-8256-46f1-aed4-bc03bed73616');
+			}
+
+			if (body.name != null) {
+				await transaction.findBy(MiPage, {
+					id: Not(pageId),
+					userId: me.id,
+					name: body.name,
+				}).then(result => {
+					if (result.length > 0) {
+						throw new IdentifiableError('d05bfe24-24b6-4ea2-a3ec-87cc9bf4daa4');
+					}
+				});
+			}
+
+			await transaction.update(MiPage, page.id, {
+				updatedAt: new Date(),
+				title: body.title,
+				name: body.name,
+				summary: body.summary === undefined ? page.summary : body.summary,
+				content: body.content,
+				variables: body.variables,
+				script: body.script,
+				alignCenter: body.alignCenter,
+				hideTitleWhenPinned: body.hideTitleWhenPinned,
+				font: body.font,
+				eyeCatchingImageId: body.eyeCatchingImage === undefined ? undefined : (body.eyeCatchingImage?.id ?? null),
+			});
+
+			console.log("page.content", page.content);
+
+			if (body.content != null) {
+				const beforeReferencedNotes = this.collectReferencedNotes(page.content);
+				const afterReferencedNotes = this.collectReferencedNotes(body.content);
+
+				const removedNotes = beforeReferencedNotes.filter(noteId => !afterReferencedNotes.includes(noteId));
+				const addedNotes = afterReferencedNotes.filter(noteId => !beforeReferencedNotes.includes(noteId));
+
+				if (removedNotes.length > 0) {
+					await transaction.decrement(MiNote, { id: In(removedNotes) }, 'pageCount', 1);
+				}
+				if (addedNotes.length > 0) {
+					await transaction.increment(MiNote, { id: In(addedNotes) }, 'pageCount', 1);
+				}
+			}
+		});
+	}
+
+	@bindThis
+	public async delete(me: MiUser, pageId: MiPage['id']): Promise<void> {
+		await this.db.transaction(async (transaction) => {
+			const page = await transaction.findOne(MiPage, {
+				where: {
+					id: pageId,
+				},
+				lock: { mode: 'pessimistic_write' }, // same lock level as DELETE
+			});
+
+			if (page == null) {
+				throw new IdentifiableError('66aefd3c-fdb2-4a71-85ae-cc18bea85d3f');
+			}
+
+			if (!await this.roleService.isModerator(me) && page.userId !== me.id) {
+				throw new IdentifiableError('d0017699-8256-46f1-aed4-bc03bed73616');
+			}
+
+			await transaction.delete(MiPage, page.id);
+
+			if (page.userId !== me.id) {
+				const user = await this.usersRepository.findOneByOrFail({ id: page.userId });
+				this.moderationLogService.log(me, 'deletePage', {
+					pageId: page.id,
+					pageUserId: page.userId,
+					pageUserUsername: user.username,
+					page,
+				});
+			}
+
+			const referencedNotes = this.collectReferencedNotes(page.content);
+			if (referencedNotes.length > 0) {
+				await transaction.decrement(MiNote, { id: In(referencedNotes) }, 'pageCount', 1);
+			}
+		});
+	}
+
+	collectReferencedNotes(content: MiPage['content']): string[] {
+		const referencingNotes = new Set<string>();
+		const recursiveCollect = (content: unknown[]) => {
+			for (const contentElement of content) {
+				if (typeof contentElement === 'object'
+					&& contentElement !== null
+					&& 'type' in contentElement) {
+					if (contentElement.type === 'note'
+						&& 'note' in contentElement
+						&& typeof contentElement.note === 'string') {
+						referencingNotes.add(contentElement.note);
+					}
+					if (contentElement.type === 'section'
+						&& 'children' in contentElement
+						&& Array.isArray(contentElement.children)) {
+						recursiveCollect(contentElement.children);
+					}
+				}
+			}
+		};
+		recursiveCollect(content);
+		return [...referencingNotes];
+	}
+}