refactor: separated route logic from server startup

src/routes.js

@@ -0,0 +1,85 @@
+import express from 'express';
+import path from 'path';
+import fs from 'fs';
+import { fetchCalendarData, sanitizeFilename, createCalendarComponent, addEventsToCalendar, saveCalendarFile, MERGED_CALENDARS_DIR } from './calendarUtil.js';
+
+const router = express.Router();
+
+// Merge calendars endpoint
+router.post('/merge', async (req, res) => {
+    const { linkGroupName, calendars } = req.body;
+
+    // Validate the input
+    if (!linkGroupName || !Array.isArray(calendars) || calendars.length === 0) {
+        return res.status(400).json({ error: 'Invalid input. Please provide a linkGroupName and at least one calendar.' });
+    }
+
+    try {
+        // Sanitize the linkGroupName to create a valid filename
+        const sanitizedLinkGroupName = sanitizeFilename(linkGroupName);
+        const filename = `${sanitizedLinkGroupName}.ics`;
+
+        // Fetch calendar data
+        const results = await Promise.all(calendars.map(fetchCalendarData));
+        
+        // Generate merged calendar using ical.js
+        const calendarComponent = createCalendarComponent(linkGroupName);
+        addEventsToCalendar(calendarComponent, results);
+        
+        // Save the calendar to a file
+        saveCalendarFile(filename, calendarComponent.toString());
+
+        // Save the user input and sanitizedLinkGroupName in a separate JSON file
+        saveCalendarFile(`${sanitizedLinkGroupName}.json`, JSON.stringify({ linkGroupName, calendars }, null, 2));
+
+        res.json({ url: `${req.protocol}://${req.get('host')}/calendar/${sanitizedLinkGroupName}` });
+    } catch (error) {
+        console.error('Error merging calendars:', error.message);
+        res.status(500).json({ error: 'Failed to merge calendars' });
+    }
+});
+
+// Refresh calendar if outdated
+async function refreshCalendarData(calendarName) {
+    const jsonFilePath = path.join(MERGED_CALENDARS_DIR, `${calendarName}.json`);
+    console.log(`Refreshing calendar data for: ${calendarName}`);
+
+    // Read the JSON file to get the source URL and other details
+    const { calendars } = JSON.parse(fs.readFileSync(jsonFilePath, 'utf-8'));
+
+    const results = await Promise.all(calendars.map(fetchCalendarData));
+    const calendarComponent = createCalendarComponent(calendarName);
+    addEventsToCalendar(calendarComponent, results);
+
+    saveCalendarFile(`${calendarName}.ics`, calendarComponent.toString());
+    console.log('Calendar data refreshed and saved.');
+}
+
+// Serve the merged calendar file and refresh if older than an hour
+router.get('/calendar/:name', async (req, res) => {
+    const calendarName = req.params.name;
+    const icsFilePath = path.join(MERGED_CALENDARS_DIR, `${calendarName}.ics`);
+
+    try {
+        // Check if the .ics file exists
+        console.log(`Serving calendar for: ${calendarName}`);
+        if (fs.existsSync(icsFilePath)) {
+            const stats = fs.statSync(icsFilePath);
+            const isOutdated = new Date() - new Date(stats.mtime) > 60 * 60 * 1000;
+
+            if (isOutdated){
+                console.log(`Calendar ${calendarName} is outdated. Refreshing...`);
+                await refreshCalendarData(calendarName);
+            }
+            res.setHeader('Content-Type', 'text/calendar');
+            res.sendFile(icsFilePath);
+        } else {
+            res.status(404).json({ error: 'Calendar not found.' });
+        }
+    } catch (error) {
+        console.error('Error retrieving calendar data:', error.message);
+        res.status(500).json({ error: 'Failed to retrieve calendar data.' });
+    }
+});
+
+export default router;