Add simple limit enforcing

For now it is 25 messages in the last 24 horus.

src/index.ts

@@ -30,6 +30,41 @@ discord.on("messageCreate", async message => {
   if (message.author.bot) return;
   if (!message.mentions.has(message.client.user)) return;
 
+  const userLimits = await database.limits.findUnique({
+    where: {
+      user: BigInt(message.author.id)
+    }
+  });
+
+  let limit = 25;
+
+  if (userLimits?.limit) {
+    limit = userLimits.limit;
+  }
+
+  if (!userLimits?.vip) {
+    const usedLimit = await database.usage.count({
+      select: { _all: true },
+      where: {
+        user: BigInt(message.author.id),
+        timestamp: {
+          gte: new Date(message.createdTimestamp - 1000*60*60*24 /*24 hours */)
+        }
+      },
+    });
+
+    if (usedLimit._all >= limit) {
+      message.react("🛑");
+      message.author.dmChannel?.send({
+        embeds: [{
+          color: 0xff0000,
+          description: `You've used up your message limit for today, ${limit} requrests in last 24 hours`
+        }]
+      });
+      return;
+    }
+  }
+
   const messagesForChannel = channelsRunning.ensure(message.channelId, () => {return [] as DiscordApi.Message[];} );
   const shouldStart = messagesForChannel.length == 0;
   messagesForChannel.push(message);