Refactoring

app/src/main/java/eu/faircode/email/DB.java

@@ -422,10 +422,10 @@ public abstract class DB extends RoomDatabase {
 
     private static void createTriggers(@NonNull SupportSQLiteDatabase db) {
         List<String> image = new ArrayList<>();
-        for (String img : Helper.IMAGE_TYPES)
+        for (String img : ImageHelper.IMAGE_TYPES)
             image.add("'" + img + "'");
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
-            for (String img : Helper.IMAGE_TYPES8)
+            for (String img : ImageHelper.IMAGE_TYPES8)
                 image.add("'" + img + "'");
         String images = TextUtils.join(",", image);
 

app/src/main/java/eu/faircode/email/EntityAttachment.java

@@ -19,6 +19,8 @@ package eu.faircode.email;
     Copyright 2018-2021 by Marcel Bokhorst (M66B)
 */
 
+import static androidx.room.ForeignKey.CASCADE;
+
 import android.content.Context;
 import android.text.TextUtils;
 
@@ -36,8 +38,6 @@ import java.util.Objects;
 
 import javax.mail.Part;
 
-import static androidx.room.ForeignKey.CASCADE;
-
 @Entity(
         tableName = EntityAttachment.TABLE_NAME,
         foreignKeys = {
@@ -91,7 +91,7 @@ public class EntityAttachment {
     }
 
     boolean isImage() {
-        return Helper.isImage(getMimeType());
+        return ImageHelper.isImage(getMimeType());
     }
 
     boolean isEncryption() {

app/src/main/java/eu/faircode/email/FragmentCompose.java

@@ -7007,7 +7007,7 @@ public class FragmentCompose extends FragmentBase {
         Long size;
 
         boolean isImage() {
-            return Helper.isImage(type);
+            return ImageHelper.isImage(type);
         }
     }
 

app/src/main/java/eu/faircode/email/Helper.java

@@ -121,7 +121,6 @@ import java.text.DecimalFormat;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.Comparator;
 import java.util.Date;
 import java.util.List;
@@ -175,21 +174,6 @@ public class Helper {
                     ")+"
     );
 
-    // https://developer.android.com/guide/topics/media/media-formats#image-formats
-    static final List<String> IMAGE_TYPES = Collections.unmodifiableList(Arrays.asList(
-            "image/bmp",
-            "image/gif",
-            "image/jpeg",
-            "image/jpg",
-            "image/png",
-            "image/webp"
-    ));
-
-    static final List<String> IMAGE_TYPES8 = Collections.unmodifiableList(Arrays.asList(
-            "image/heic",
-            "image/heif"
-    ));
-
     private static final ExecutorService executor = getBackgroundExecutor(1, "helper");
 
     static ExecutorService getBackgroundExecutor(int threads, final String name) {
@@ -1579,14 +1563,6 @@ public class Helper {
         //intent.putExtra(DocumentsContract.EXTRA_INITIAL_URI, Uri.fromFile(initial));
     }
 
-    static boolean isImage(String mimeType) {
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
-            if (IMAGE_TYPES8.contains(mimeType))
-                return true;
-
-        return IMAGE_TYPES.contains(mimeType);
-    }
-
     // Cryptography
 
     static String sha256(String data) throws NoSuchAlgorithmException {

app/src/main/java/eu/faircode/email/ImageHelper.java

@@ -75,7 +75,10 @@ import java.net.URLDecoder;
 import java.nio.charset.StandardCharsets;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
+import java.util.Arrays;
+import java.util.Collections;
 import java.util.Date;
+import java.util.List;
 import java.util.Map;
 import java.util.WeakHashMap;
 import java.util.concurrent.ExecutorService;
@@ -91,6 +94,29 @@ class ImageHelper {
     private static final int MAX_PROBE = 64 * 1024; // bytes
     private static final int SLOW_CONNECTION = 2 * 1024; // Kbps
 
+    // https://developer.android.com/guide/topics/media/media-formats#image-formats
+    static final List<String> IMAGE_TYPES = Collections.unmodifiableList(Arrays.asList(
+            "image/bmp",
+            "image/gif",
+            "image/jpeg",
+            "image/jpg",
+            "image/png",
+            "image/webp"
+    ));
+
+    static final List<String> IMAGE_TYPES8 = Collections.unmodifiableList(Arrays.asList(
+            "image/heic",
+            "image/heif"
+    ));
+
+    static boolean isImage(String mimeType) {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
+            if (IMAGE_TYPES8.contains(mimeType))
+                return true;
+
+        return IMAGE_TYPES.contains(mimeType);
+    }
+
     static Bitmap generateIdenticon(@NonNull String email, int size, int pixels, Context context) {
         byte[] hash = getHash(email);
         float h = Math.abs(email.hashCode()) % 360;