Message splitting utility

src/modules/chimeIn.js

@@ -11,6 +11,7 @@
 
 import { info, warn, error as logError } from '../logger.js';
 import { OPENCLAW_URL, OPENCLAW_TOKEN } from './ai.js';
+import { splitMessage, needsSplitting } from '../utils/splitMessage.js';
 
 // ── Per-channel state ──────────────────────────────────────────────────────────
 // Map<channelId, { messages: Array<{author, content}>, counter: number, lastActive: number, abortController: AbortController|null }>
@@ -258,20 +259,8 @@ export async function accumulate(message, config) {
         warn('ChimeIn suppressed empty response', { channelId });
       } else {
         // Send as a plain channel message (not a reply)
-        if (response.length > 2000) {
-          // Split on word boundaries to avoid breaking mid-word/URL/emoji
-          const chunks = [];
-          let remaining = response;
-          while (remaining.length > 0) {
-            if (remaining.length <= 1990) {
-              chunks.push(remaining);
-              break;
-            }
-            let splitAt = remaining.lastIndexOf(' ', 1990);
-            if (splitAt <= 0) splitAt = 1990;
-            chunks.push(remaining.slice(0, splitAt));
-            remaining = remaining.slice(splitAt).trimStart();
-          }
+        if (needsSplitting(response)) {
+          const chunks = splitMessage(response);
           for (const chunk of chunks) {
             await message.channel.send(chunk);
           }

src/modules/events.js

@@ -7,6 +7,7 @@ import { sendWelcomeMessage } from './welcome.js';
 import { isSpam, sendSpamAlert } from './spam.js';
 import { generateResponse } from './ai.js';
 import { accumulate, resetCounter } from './chimeIn.js';
+import { splitMessage, needsSplitting } from '../utils/splitMessage.js';
 
 /**
  * Register bot ready event handler
@@ -100,8 +101,8 @@ export function registerMessageCreateHandler(client, config, healthMonitor) {
         );
 
         // Split long responses
-        if (response.length > 2000) {
-          const chunks = response.match(/[\s\S]{1,1990}/g) || [];
+        if (needsSplitting(response)) {
+          const chunks = splitMessage(response);
           for (const chunk of chunks) {
             await message.channel.send(chunk);
           }

src/utils/splitMessage.js

@@ -0,0 +1,61 @@
+/**
+ * Split Message Utility
+ * Splits long messages to fit within Discord's 2000-character limit.
+ */
+
+/**
+ * Discord's maximum message length.
+ */
+const DISCORD_MAX_LENGTH = 2000;
+
+/**
+ * Safe chunk size leaving room for potential overhead.
+ */
+const SAFE_CHUNK_SIZE = 1990;
+
+/**
+ * Splits a message into chunks that fit within Discord's character limit.
+ * Attempts to split on word boundaries to avoid breaking words, URLs, or emoji.
+ *
+ * @param {string} text - The text to split
+ * @param {number} [maxLength=1990] - Maximum length per chunk (default 1990 to stay under 2000)
+ * @returns {string[]} Array of text chunks, each within the specified limit
+ */
+export function splitMessage(text, maxLength = SAFE_CHUNK_SIZE) {
+  if (!text || text.length <= maxLength) {
+    return text ? [text] : [];
+  }
+
+  const chunks = [];
+  let remaining = text;
+
+  while (remaining.length > 0) {
+    if (remaining.length <= maxLength) {
+      chunks.push(remaining);
+      break;
+    }
+
+    // Try to find a space to split on (word boundary)
+    let splitAt = remaining.lastIndexOf(' ', maxLength);
+
+    // If no space found or it's at the start, force split at maxLength
+    if (splitAt <= 0) {
+      splitAt = maxLength;
+    }
+
+    chunks.push(remaining.slice(0, splitAt));
+    remaining = remaining.slice(splitAt).trimStart();
+  }
+
+  return chunks;
+}
+
+/**
+ * Checks if a message exceeds Discord's character limit.
+ *
+ * @param {string} text - The text to check
+ * @returns {boolean} True if the message needs splitting
+ */
+export function needsSplitting(text) {
+  return text && text.length > DISCORD_MAX_LENGTH;
+}