feat: add announcement channels, publishing and following (#3090)

fluxer_api/src/api/channel/services/message/MessagePersistenceService.ts

@@ -15,6 +15,8 @@ import {MessageEmbedAttachmentResolver} from '@app/api/channel/services/message/
 import {
 	assertAttachmentFileSizesWithinLimit,
 	collectMessageAttachments,
+	isCrosspostCopy,
+	keepOwnedEmbedAttachments,
 } from '@app/api/channel/services/message/MessageHelpers';
 import {MessageStickerService} from '@app/api/channel/services/message/MessageStickerService';
 import {getContentMessage} from '@app/api/content_i18n/ContentI18n';
@@ -111,6 +113,9 @@ interface CreateMessageParams {
 	};
 	allowEmbeds?: boolean;
 	dmNsfwContext?: DmNsfwContext;
+	processedEmbeds?: Array<MessageEmbed>;
+	processedStickerItems?: Array<MessageStickerItem>;
+	skipDeferredEmbeds?: boolean;
 }
 
 export class MessagePersistenceService {
@@ -190,8 +195,12 @@ export class MessagePersistenceService {
 		const allowEmbeds = params.allowEmbeds ?? true;
 		let initialEmbeds: Array<MessageEmbed> | null = null;
 		let hasUncachedUrls = false;
-		const referencedFilenames = this.embedAttachmentResolver.collectReferencedAttachmentFilenames(params.embeds);
-		if (allowEmbeds) {
+		const referencedFilenames = params.processedEmbeds
+			? new Set<string>()
+			: this.embedAttachmentResolver.collectReferencedAttachmentFilenames(params.embeds);
+		if (params.processedEmbeds) {
+			initialEmbeds = params.processedEmbeds.length > 0 ? params.processedEmbeds : null;
+		} else if (allowEmbeds) {
 			const resolvedEmbeds = this.embedAttachmentResolver.resolveEmbedAttachmentUrls({
 				embeds: params.embeds,
 				attachments: processedAttachments.map(mapAttachmentForEmbedResolution),
@@ -299,6 +308,9 @@ export class MessagePersistenceService {
 		params: CreateMessageParams,
 		authorId: UserID | null,
 	): Promise<Array<MessageStickerItem>> {
+		if (params.processedStickerItems) {
+			return params.processedStickerItems;
+		}
 		if (!params.stickerIds || params.stickerIds.length === 0) {
 			return [];
 		}
@@ -320,7 +332,7 @@ export class MessagePersistenceService {
 	}): Promise<() => Promise<void>> {
 		const {message, params, authorId, allowEmbeds, hasUncachedUrls, isNSFWAllowed} = context;
 		const operations: Array<Promise<unknown>> = [];
-		const trackedAttachments = collectMessageAttachments(message);
+		const trackedAttachments = isCrosspostCopy(message) ? [] : collectMessageAttachments(message);
 		if (trackedAttachments.length > 0) {
 			const uploadedAt = snowflakeToDate(params.messageId);
 			const decayPayloads = trackedAttachments.map((att) => ({
@@ -334,7 +346,7 @@ export class MessagePersistenceService {
 			operations.push(this.attachmentDecayService.upsertMany(decayPayloads));
 		}
 		let enqueueDeferredEmbeds: () => Promise<void> = () => Promise.resolve();
-		if (allowEmbeds && hasUncachedUrls) {
+		if (allowEmbeds && hasUncachedUrls && !params.skipDeferredEmbeds) {
 			enqueueDeferredEmbeds = () =>
 				this.embedService.enqueueUrlEmbedExtraction(
 					params.channelId,
@@ -524,6 +536,7 @@ export class MessagePersistenceService {
 				isBugHunterBot: params.isBugHunterBot,
 			});
 			if (embedsExplicitlyProvided) {
+				keepOwnedEmbedAttachments(message, initialEmbeds);
 				updatedRowData.embeds = initialEmbeds;
 			} else {
 				const preservedEmbeds = message.embeds