Initial

src/utils/rate-limiter.ts

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+import PQueue from 'p-queue';
+import type { Config } from '../config/index.js';
+import type { Logger } from './logger.js';
+
+export class RateLimiter {
+  private queue: PQueue;
+  private lastMessageTime: number = 0;
+  private messagesThisHour: number = 0;
+  private hourStartTime: number = Date.now();
+
+  constructor(
+    private config: Config,
+    private logger: Logger
+  ) {
+    this.queue = new PQueue({ concurrency: 1 });
+  }
+
+  async throttle<T>(fn: () => Promise<T>): Promise<T> {
+    return this.queue.add(async () => {
+      const now = Date.now();
+
+      // Reset hourly counter if needed
+      if (now - this.hourStartTime > 3600000) {
+        this.messagesThisHour = 0;
+        this.hourStartTime = now;
+        this.logger.debug('Hourly rate limit counter reset');
+      }
+
+      // Check hourly limit
+      if (this.messagesThisHour >= this.config.rateLimit.maxMessagesPerHour) {
+        const waitTime = 3600000 - (now - this.hourStartTime);
+        this.logger.info(`Hourly limit reached, waiting ${Math.round(waitTime / 60000)} minutes`);
+        await this.sleep(waitTime);
+        this.messagesThisHour = 0;
+        this.hourStartTime = Date.now();
+      }
+
+      // Enforce minimum delay with jitter
+      const timeSinceLastMessage = now - this.lastMessageTime;
+      const minDelay = this.config.rateLimit.minDelayBetweenMessagesMs;
+      const jitter = Math.random() * this.config.rateLimit.jitterMs;
+
+      if (this.lastMessageTime > 0 && timeSinceLastMessage < minDelay) {
+        const waitTime = minDelay - timeSinceLastMessage + jitter;
+        this.logger.debug(`Rate limiting: waiting ${Math.round(waitTime / 1000)} seconds`);
+        await this.sleep(waitTime);
+      }
+
+      this.lastMessageTime = Date.now();
+      this.messagesThisHour++;
+
+      return fn();
+    }) as Promise<T>;
+  }
+
+  private sleep(ms: number): Promise<void> {
+    return new Promise((resolve) => setTimeout(resolve, ms));
+  }
+
+  getStats(): { messagesThisHour: number; minutesSinceLastMessage: number } {
+    return {
+      messagesThisHour: this.messagesThisHour,
+      minutesSinceLastMessage: Math.round((Date.now() - this.lastMessageTime) / 60000),
+    };
+  }
+}