fix: dedupe inbound messages across providers

src/auto-reply/reply/inbound-dedupe.test.ts

@@ -0,0 +1,81 @@
+import { describe, expect, it } from "vitest";
+
+import type { MsgContext } from "../templating.js";
+import {
+  buildInboundDedupeKey,
+  resetInboundDedupe,
+  shouldSkipDuplicateInbound,
+} from "./inbound-dedupe.js";
+
+describe("inbound dedupe", () => {
+  it("builds a stable key when MessageSid is present", () => {
+    const ctx: MsgContext = {
+      Provider: "telegram",
+      OriginatingChannel: "telegram",
+      OriginatingTo: "telegram:123",
+      MessageSid: "42",
+    };
+    expect(buildInboundDedupeKey(ctx)).toBe("telegram|telegram:123|42");
+  });
+
+  it("skips duplicates with the same key", () => {
+    resetInboundDedupe();
+    const ctx: MsgContext = {
+      Provider: "whatsapp",
+      OriginatingChannel: "whatsapp",
+      OriginatingTo: "whatsapp:+1555",
+      MessageSid: "msg-1",
+    };
+    expect(shouldSkipDuplicateInbound(ctx, { now: 100 })).toBe(false);
+    expect(shouldSkipDuplicateInbound(ctx, { now: 200 })).toBe(true);
+  });
+
+  it("does not dedupe when the peer changes", () => {
+    resetInboundDedupe();
+    const base: MsgContext = {
+      Provider: "whatsapp",
+      OriginatingChannel: "whatsapp",
+      MessageSid: "msg-1",
+    };
+    expect(
+      shouldSkipDuplicateInbound(
+        { ...base, OriginatingTo: "whatsapp:+1000" },
+        { now: 100 },
+      ),
+    ).toBe(false);
+    expect(
+      shouldSkipDuplicateInbound(
+        { ...base, OriginatingTo: "whatsapp:+2000" },
+        { now: 200 },
+      ),
+    ).toBe(false);
+  });
+
+  it("does not dedupe across session keys", () => {
+    resetInboundDedupe();
+    const base: MsgContext = {
+      Provider: "whatsapp",
+      OriginatingChannel: "whatsapp",
+      OriginatingTo: "whatsapp:+1555",
+      MessageSid: "msg-1",
+    };
+    expect(
+      shouldSkipDuplicateInbound(
+        { ...base, SessionKey: "agent:alpha:main" },
+        { now: 100 },
+      ),
+    ).toBe(false);
+    expect(
+      shouldSkipDuplicateInbound(
+        { ...base, SessionKey: "agent:bravo:main" },
+        { now: 200 },
+      ),
+    ).toBe(false);
+    expect(
+      shouldSkipDuplicateInbound(
+        { ...base, SessionKey: "agent:alpha:main" },
+        { now: 300 },
+      ),
+    ).toBe(true);
+  });
+});