feat: add countdown command

.env.example

@@ -3,4 +3,9 @@ DB_URL=
 ADMIN_ID=
 AES_PASSPHRASE=
 SERVER_URI=
-PORT=
+PORT=
+SERVER_URI=
+CLIENT_ID=
+TENANT_ID=
+CLIENT_SECRET=
+UW_API_KEY=

commands/countdown.js

@@ -0,0 +1,41 @@
+const Discord = require("discord.js");
+const fetch = require("node-fetch");
+const { DateTime } = require("luxon");
+
+let examsEndDate;
+let termEndDate;
+
+module.exports = {
+    name: "countdown",
+    description: "Count the number of days until the current academic term is over",
+    aliases: ['fml', 'count'],
+    args: false,
+    guildOnly: false,
+    displayHelp: true,
+    async execute(message) {
+        if (!examsEndDate || DateTime.local() > termEndDate) {
+            const currentTermResponse = await fetch('https://openapi.data.uwaterloo.ca/v3/Terms/current', {
+                method: 'GET',
+                headers: {
+                    'X-API-KEY': process.env.UW_API_KEY
+                }
+            });
+            const currentTerm = await currentTermResponse.json();
+            termEndDate = DateTime.fromISO(currentTerm.termEndDate, { zone: 'America/Toronto' });
+
+            const importantDateResponse = await fetch('https://openapi.data.uwaterloo.ca/v3/ImportantDates', {
+                method: 'GET',
+                headers: {
+                    'X-API-KEY': process.env.UW_API_KEY
+                }
+            });
+            const importantDates = await importantDateResponse.json();
+
+            const examEndEvent = importantDates.find(date => date?.name === "Final examinations end" && date?.details?.some(detail => detail?.termName === currentTerm.name));
+            examsEndDate = DateTime.fromISO(examEndEvent.details.find(detail => detail?.termName === currentTerm.name ).startDate);
+        }
+
+        let timeDiff = examsEndDate.diff(DateTime.local(), 'days');
+        message.channel.send(`There are about ${Math.floor(timeDiff.values.days)} more days until this term is over!`);
+    }
+};