feat: slash command registration

src/core/modules.ts

@@ -259,6 +259,7 @@ export class RootModule extends BaseModule {
       this.config = botConfig.modules[this.name];
       this.enabled = this.config.enabled;
     } else {
+      this.config = {enabled: false};
       logEvent(
         EventCategory.Error,
         'core',

src/core/permissions.ts

@@ -414,7 +414,9 @@ function checkContextBlockForInteraction(
 }
 
 /** Convert an {@link ManagementPermission} to be of type {@link PermissionsBitFlag} */
-function permissionConfigToBitFlag(permission: ManagementPermission | string) {
+export function permissionConfigToBitFlag(
+  permission: ManagementPermission | string
+) {
   // have fun!
   switch (permission) {
     case 'timeout':

src/core/slash_commands.ts

@@ -44,6 +44,8 @@
   ModuleInputOption,
   ModuleOptionType,
 } from './modules.js';
+import {updateShorthandPropertyAssignment} from 'typescript';
+import {permissionConfigToBitFlag} from './permissions.js';
 
 type SlashCommandOption =
   | SlashCommandAttachmentOption
@@ -96,10 +98,26 @@
 export async function generateSlashCommandForModule(
   module: RootModule
 ): Promise<SlashCommandBuilder> {
+  // calculate the permissions configured for the slash command, so that it's hidden for those who don't have
+  // execution permission
+  // https://discord.com/developers/docs/topics/permissions
+  // 1 << 31 is the flag for "using bot commands"
+  // i would have used zero, but the command is entirely disabled if 0
+  let permissionBitFlags = BigInt('0x0000000080000000');
+  const requiredPermissions =
+    (module.config.permissions ?? {requiredPermissions: []})
+      .requiredPermissions ?? [];
+  for (const permission of requiredPermissions) {
+    // perform a binary OR operation to combine the bitflags together
+    // https://discordjs.guide/slash-commands/permissions.html#member-permissions
+    permissionBitFlags |= permissionConfigToBitFlag(permission);
+  }
+
   // translate the module to slash command form
   const slashCommand = new SlashCommandBuilder()
     .setName(module.name)
-    .setDescription(module.description);
+    .setDescription(module.description)
+    .setDefaultMemberPermissions(permissionBitFlags);
 
   // if the module has submodules, than register those as subcommands
   // https://discord.com/developers/docs/interactions/application-commands#subcommands-and-subcommand-groups