refactor: add inbound context helpers

src/channels/sender-identity.ts

@@ -0,0 +1,38 @@
+import type { MsgContext } from "../auto-reply/templating.js";
+import { normalizeChatType } from "./chat-type.js";
+
+export function validateSenderIdentity(ctx: MsgContext): string[] {
+  const issues: string[] = [];
+
+  const chatType = normalizeChatType(ctx.ChatType);
+  const isDirect = chatType === "direct";
+
+  const senderId = ctx.SenderId?.trim() || "";
+  const senderName = ctx.SenderName?.trim() || "";
+  const senderUsername = ctx.SenderUsername?.trim() || "";
+  const senderE164 = ctx.SenderE164?.trim() || "";
+
+  if (!isDirect) {
+    if (!senderId && !senderName && !senderUsername && !senderE164) {
+      issues.push("missing sender identity (SenderId/SenderName/SenderUsername/SenderE164)");
+    }
+  }
+
+  if (senderE164) {
+    if (!/^\+\d{3,}$/.test(senderE164)) {
+      issues.push(`invalid SenderE164: ${senderE164}`);
+    }
+  }
+
+  if (senderUsername) {
+    if (senderUsername.includes("@")) issues.push(`SenderUsername should not include "@": ${senderUsername}`);
+    if (/\s/.test(senderUsername)) issues.push(`SenderUsername should not include whitespace: ${senderUsername}`);
+  }
+
+  if (ctx.SenderId != null && !senderId) {
+    issues.push("SenderId is set but empty");
+  }
+
+  return issues;
+}
+