feat: add access control

packages/api/utils/access-control.ts

@@ -0,0 +1,50 @@
+import { isRoot } from '@roleypoly/api/utils/api-tools';
+import {
+  GuildAccessControl,
+  GuildSlug,
+  Member,
+  UserGuildPermissions,
+} from '@roleypoly/types';
+import { xor } from 'lodash';
+
+export const memberPassesAccessControl = (
+  guildSlug: GuildSlug,
+  member: Member,
+  accessControl: GuildAccessControl
+): boolean => {
+  // Root has a bypass
+  if (isRoot(member.user?.id || '')) {
+    return true;
+  }
+
+  // Admin and Manager has a bypass
+  if (guildSlug.permissionLevel !== UserGuildPermissions.User) {
+    return true;
+  }
+
+  // Block pending members, "Welcome Screen" feature
+  if (accessControl.blockPending && member.pending) {
+    return false;
+  }
+
+  // If member has roles in the blockList, block.
+  // Blocklist takes precedence over allowlist
+  // We use xor because xor([1, 3], [2, 3]) returns [3]), e.g. present in both lists
+  if (
+    accessControl.blockList &&
+    xor(member.roles, accessControl.blockList).length !== 0
+  ) {
+    return false;
+  }
+
+  // If there is an allowList, and the member is not in it, block.
+  // If thew allowList is empty, we bypass this.
+  if (
+    accessControl.allowList &&
+    xor(member.roles, accessControl.allowList).length === 0
+  ) {
+    return false;
+  }
+
+  return true;
+};