feat: add fallbacks to all the supported content types

.changeset/gorgeous-pugs-reply.md

@@ -0,0 +1,8 @@
+---
+"@xmtp/content-type-remote-attachment": minor
+"@xmtp/content-type-read-receipt": minor
+"@xmtp/content-type-reaction": minor
+"@xmtp/content-type-reply": minor
+---
+
+Add dummy fallback field to all content types

packages/content-type-reaction/src/Reaction.ts

@@ -64,4 +64,8 @@ export class ReactionCodec implements ContentCodec<Reaction> {
       content: new TextDecoder().decode(content.content),
     };
   }
+
+  fallback(): string | undefined {
+    return "Error: Sorry, this app cannot display reactions";
+  }
 }

packages/content-type-read-receipt/src/ReadReceipt.ts

@@ -39,4 +39,8 @@ export class ReadReceiptCodec implements ContentCodec<ReadReceipt> {
       timestamp,
     };
   }
+
+  fallback(): string | undefined {
+    return undefined;
+  }
 }

packages/content-type-remote-attachment/src/Attachment.ts

@@ -37,4 +37,8 @@ export class AttachmentCodec implements ContentCodec<Attachment> {
       data: content.content,
     };
   }
+
+  fallback(): string | undefined {
+    return "Error: Sorry, this app cannot display attachments";
+  }
 }

packages/content-type-remote-attachment/src/RemoteAttachment.ts

@@ -161,4 +161,8 @@ export class RemoteAttachmentCodec implements ContentCodec<RemoteAttachment> {
       filename: content.parameters.filename,
     };
   }
+
+  fallback(): string | undefined {
+    return "Error: Sorry, this app cannot display attachments";
+  }
 }

packages/content-type-reply/src/Reply.ts

@@ -84,4 +84,8 @@ export class ReplyCodec implements ContentCodec<Reply> {
       content: codec.decode(decodedContent as EncodedContent, codecs),
     };
   }
+
+  fallback(): string | undefined {
+    return "Error: Sorry, this app cannot display quote replies";
+  }
 }