add exif stripping, and convert to png by default

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

@@ -0,0 +1,82 @@
+import { Injectable } from '@nestjs/common';
+import icoToPng from 'ico-to-png';
+import { AsyncFailable, Fail } from 'picsur-shared/dist/types';
+import sharp from 'sharp';
+import { UsrPreferenceService } from '../../collections/preferencesdb/usrpreferencedb.service';
+import {
+  FullMime,
+  ImageMime,
+  SupportedMimeCategory
+} from '../../models/dto/mimes.dto';
+
+@Injectable()
+export class ImageProcessorService {
+  constructor(private readonly userPref: UsrPreferenceService) {}
+
+  public async process(
+    image: Buffer,
+    mime: FullMime,
+    userid: string,
+  ): AsyncFailable<Buffer> {
+    if (mime.type === SupportedMimeCategory.Image) {
+      return await this.processStill(image, mime, {});
+    } else if (mime.type === SupportedMimeCategory.Animation) {
+      return await this.processAnimation(image, mime, {});
+    } else {
+      return Fail('Unsupported mime type');
+    }
+
+    // // nothing happens right now
+    // const keepOriginal = await this.userPref.getBooleanPreference(
+    //   userid,
+    //   UsrPreference.KeepOriginal,
+    // );
+    // if (HasFailed(keepOriginal)) return keepOriginal;
+
+    // if (keepOriginal) {
+    // }
+  }
+
+  private async processStill(
+    image: Buffer,
+    mime: FullMime,
+    options: {},
+  ): AsyncFailable<Buffer> {
+    let processedImage = image;
+
+    switch (mime.mime) {
+      case ImageMime.ICO:
+        processedImage = await icoToPng(processedImage, 512);
+        mime.mime = ImageMime.PNG;
+        break;
+
+      case ImageMime.BMP:
+      case ImageMime.TIFF:
+      case ImageMime.WEBP:
+      case ImageMime.PNG:
+      case ImageMime.JPEG:
+        processedImage = await sharp(processedImage)
+          .png({
+            compressionLevel: 9,
+            effort: 10,
+          })
+          .toBuffer();
+        mime.mime = ImageMime.PNG;
+        break;
+
+      default:
+        return Fail('Unsupported mime type');
+    }
+
+    return processedImage;
+  }
+
+  private async processAnimation(
+    image: Buffer,
+    mime: FullMime,
+    options: {},
+  ): AsyncFailable<Buffer> {
+    // Apng and gif are stored as is for now
+    return image;
+  }
+}