refactor: rename controllers to handlers and handlers to helpers (#660)

* refactor: rename controllers to handlers and handlers to helpers

* fmt

src/handlers/guilds/GUILD_UPDATE.ts

@@ -0,0 +1,48 @@
+import { eventHandlers } from "../../bot.ts";
+import {
+  DiscordPayload,
+  GuildUpdateChange,
+  UpdateGuildPayload,
+} from "../../types/mod.ts";
+import { cacheHandlers } from "../../cache.ts";
+
+export async function handleGuildUpdate(data: DiscordPayload) {
+  const payload = data.d as UpdateGuildPayload;
+  const cachedGuild = await cacheHandlers.get("guilds", payload.id);
+  if (!cachedGuild) return;
+
+  const keysToSkip = [
+    "roles",
+    "guild_hashes",
+    "guild_id",
+    "max_members",
+    "emojis",
+  ];
+
+  const changes = Object.entries(payload)
+    .map(([key, value]) => {
+      if (keysToSkip.includes(key)) return;
+
+      // @ts-ignore index signature
+      const cachedValue = cachedGuild[key];
+      if (cachedValue !== value) {
+        // Guild create sends undefined and update sends false.
+        if (!cachedValue && !value) return;
+
+        if (Array.isArray(cachedValue) && Array.isArray(value)) {
+          const different = (cachedValue.length !== value.length) ||
+            cachedValue.find((val) => !value.includes(val)) ||
+            value.find((val) => !cachedValue.includes(val));
+          if (!different) return;
+        }
+
+        // @ts-ignore index signature
+        cachedGuild[key] = value;
+        return { key, oldValue: cachedValue, value };
+      }
+    }).filter((change) => change) as GuildUpdateChange[];
+
+  await cacheHandlers.set("guilds", payload.id, cachedGuild);
+
+  eventHandlers.guildUpdate?.(cachedGuild, changes);
+}