change to monorepo

backend/src/managers/imagemanager/imagemanager.service.ts

@@ -0,0 +1,46 @@
+import { Injectable } from '@nestjs/common';
+import { fileTypeFromBuffer, FileTypeResult } from 'file-type';
+import { ImageEntity } from 'src/collections/imagedb/image.entity';
+import { ImageDBService } from 'src/collections/imagedb/imagedb.service';
+import { FullMime, MimesService } from 'src/collections/imagedb/mimes.service';
+import { AsyncFailable, Fail, HasFailed } from 'src/types/failable';
+
+@Injectable()
+export class ImageManagerService {
+  constructor(
+    private readonly imagesService: ImageDBService,
+    private readonly mimesService: MimesService,
+  ) {}
+
+  async uploadImage(image: Buffer): AsyncFailable<string> {
+    const mime: FileTypeResult = await fileTypeFromBuffer(image);
+    const fullMime = await this.mimesService.getFullMime(
+      mime?.mime ?? 'extra/discard',
+    );
+    if (HasFailed(fullMime)) return fullMime;
+
+    const processedImage: Buffer = await this.processImage(image, fullMime);
+
+    const imageEntity = await this.imagesService.create(
+      processedImage,
+      fullMime.mime,
+    );
+    if (HasFailed(imageEntity)) return imageEntity;
+
+    return imageEntity.hash;
+  }
+
+  private async processImage(image: Buffer, mime: FullMime): Promise<Buffer> {
+    return image;
+  }
+
+  async retrieveImage(hash: string): AsyncFailable<ImageEntity> {
+    if (!this.validateHash(hash)) return Fail('Invalid hash');
+
+    return await this.imagesService.findOne(hash);
+  }
+
+  validateHash(hash: string): boolean {
+    return /^[a-f0-9]{64}$/.test(hash);
+  }
+}