fix: prevent duplicate outreach and follow-ups

src/services/conversation-automation.ts

@@ -1,5 +1,5 @@
 import type { OpenRouterClient } from '../ai/openrouter.js';
-import type { ConversationStateRepository } from '../database/repositories.js';
+import type { ConversationStateRepository, SentMessageRecord } from '../database/repositories.js';
 import type { Logger } from '../utils/logger.js';
 import type { RateLimiter } from '../utils/rate-limiter.js';
 import { findSellerSignal } from '../reddit/api.js';
@@ -28,6 +28,15 @@ export interface ConversationAutomationResult {
   remainingTurns: number;
 }
 
+export interface ConversationOpenerHistory {
+  getByChatRoomId(chatRoomId: string): SentMessageRecord | undefined;
+}
+
+export interface ConversationAutomationClaims {
+  tryClaim(conversationId: string, incomingKey: string): boolean;
+  markSent(conversationId: string, incomingKey: string): boolean;
+}
+
 /**
  * Sends at most one reply for each newly received user message. Durable state
  * makes retries and restarts idempotent, and every conversation stops after
@@ -38,6 +47,8 @@ export class ConversationAutomationService {
     private readonly chat: ChatService,
     private readonly ai: OpenRouterClient,
     private readonly states: ConversationStateRepository,
+    private readonly openers: ConversationOpenerHistory,
+    private readonly claims: ConversationAutomationClaims,
     private readonly rateLimiter: RateLimiter,
     private readonly logger: Logger,
     private readonly dryRun = false,
@@ -66,6 +77,13 @@ export class ConversationAutomationService {
     if (!latest || latest.isSelf) return null;
 
     const conversationId = conversation.roomId;
+    const opener = this.openers.getByChatRoomId(conversationId);
+    if (!opener || latest.timestamp <= opener.sentAt) {
+      this.logger.debug?.(
+        `[automation] Ignoring unverified inbound event for u/${conversation.username}: no confirmed post-opener response in this room`,
+      );
+      return null;
+    }
     const mapped = messages.map(({ sender, text, isSelf }) => ({ sender, text, isSelf }));
     const state = mergeConversationState(
       this.states.get(conversationId),
@@ -106,13 +124,11 @@ export class ConversationAutomationService {
       return null;
     }
 
-    const sent = await this.rateLimiter.throttle(
-      () => this.chat.sendChatMessage(conversation.url!, reply),
-      (success) => success,
-      signal,
-    );
-    if (!sent) return null;
+    if (!this.claims.tryClaim(conversationId, incomingKey)) return null;
 
+    // Persist the full intended state before the remote send. If the process
+    // dies after Matrix accepts the message, both this state and the durable
+    // event claim make the retry fail closed instead of sending twice.
     state.askedForMedia = true;
     state.automation.turnsUsed += 1;
     state.automation.lastIncomingKey = incomingKey;
@@ -123,6 +139,14 @@ export class ConversationAutomationService {
       state.automation.handoffReason = 'Three automated turns have been used.';
     }
     this.states.save(conversationId, state);
+
+    const sent = await this.rateLimiter.throttle(
+      () => this.chat.sendChatMessage(conversation.url!, reply),
+      (success) => success,
+      signal,
+    );
+    if (!sent) return null;
+    this.claims.markSent(conversationId, incomingKey);
     this.logger.info(
       `[automation] Sent turn ${state.automation.turnsUsed}/${MAX_AUTOMATED_CONVERSATION_TURNS} to u/${conversation.username}`,
     );