Add pagination to !logs

src/modules/logs.js

@@ -3,12 +3,20 @@ const threads = require("../data/threads");
 const moment = require('moment');
 const utils = require("../utils");
 
+const LOG_LINES_PER_PAGE = 10;
+
 module.exports = bot => {
   const addInboxServerCommand = (...args) => threadUtils.addInboxServerCommand(bot, ...args);
 
-  addInboxServerCommand('logs', (msg, args, thread) => {
-    async function getLogs(userId) {
-      const userThreads = await threads.getClosedThreadsByUserId(userId);
+  addInboxServerCommand('logs', async (msg, args, thread) => {
+    const firstArgUserId = utils.getUserMention(args[0]);
+    let userId = firstArgUserId
+      ? firstArgUserId
+      : thread && thread.user_id;
+
+    if (! userId) return;
+
+    let userThreads = await threads.getClosedThreadsByUserId(userId);
 
     // Descending by date
     userThreads.sort((a, b) => {
@@ -17,13 +25,31 @@ module.exports = bot => {
       return 0;
     });
 
+    // Pagination
+    const totalUserThreads = userThreads.length;
+    const maxPage = Math.ceil(totalUserThreads / LOG_LINES_PER_PAGE);
+    const inputPage = firstArgUserId ? args[1] : args[0];
+    const page = Math.max(Math.min(inputPage ? parseInt(inputPage, 10) : 1, maxPage), 1); // Clamp page to 1-<max page>
+    const isPaginated = totalUserThreads > LOG_LINES_PER_PAGE;
+    const start = (page - 1) * LOG_LINES_PER_PAGE;
+    const end = page * LOG_LINES_PER_PAGE;
+    userThreads = userThreads.slice((page - 1) * LOG_LINES_PER_PAGE, page * LOG_LINES_PER_PAGE);
+
     const threadLines = await Promise.all(userThreads.map(async thread => {
       const logUrl = await thread.getLogUrl();
       const formattedDate = moment.utc(thread.created_at).format('MMM Do [at] HH:mm [UTC]');
       return `\`${formattedDate}\`: <${logUrl}>`;
     }));
 
-      const message = `**Log files for <@${userId}>:**\n${threadLines.join('\n')}`;
+    let message = isPaginated
+      ? `**Log files for <@${userId}>** (page **${page}/${maxPage}**, showing logs **${start + 1}-${end}/${totalUserThreads}**):`
+      : `**Log files for <@${userId}>:**`;
+
+    message += `\n${threadLines.join('\n')}`;
+
+    if (isPaginated) {
+      message += `\nTo view more, add a page number to the end of the command`;
+    }
 
     // Send the list of logs in chunks of 15 lines per message
     const lines = message.split('\n');
@@ -33,17 +59,6 @@ module.exports = bot => {
     chunks.forEach(lines => {
       root = root.then(() => msg.channel.createMessage(lines.join('\n')));
     });
-    }
-
-    if (args.length > 0) {
-      // User mention/id as argument
-      const userId = utils.getUserMention(args.join(' '));
-      if (! userId) return;
-      getLogs(userId);
-    } else if (thread) {
-      // Calling !logs without args in a modmail thread returns the logs of the user of that thread
-      getLogs(thread.user_id);
-    }
   });
 
   addInboxServerCommand('loglink', async (msg, args, thread) => {