Improve permission utils, make them bigint-aware

backend/src/utils/verifyPermissions.ts

@@ -0,0 +1,54 @@
+import { Constants, Permission } from "eris";
+import { PluginData } from "knub";
+import { hasDiscordPermissions } from "./hasDiscordPermissions";
+import { LogsPlugin } from "../plugins/Logs/LogsPlugin";
+import { LogType } from "../data/LogType";
+
+const defaultErrorText = `Missing permissions.`;
+
+const camelCaseToTitleCase = str =>
+  str
+    .replace(/([a-z])([A-Z])/g, "$1 $2")
+    .split(" ")
+    .map(w => w[0].toUpperCase() + w.slice(1))
+    .join(" ");
+
+const permissionNumberToName: Map<bigint, string> = new Map();
+for (const key in Constants.Permissions) {
+  permissionNumberToName.set(BigInt(Constants.Permissions[key]), camelCaseToTitleCase(key));
+}
+
+/**
+ *
+ * @param resolvedPermissions A Permission object from e.g. GuildChannel#permissionsOf() or Member#permission
+ * @param requiredPermissions Bitmask of required permissions
+ * @param errorText Custom error text
+ */
+export function verifyPermissions(
+  pluginData: PluginData<any>,
+  resolvedPermissions: Permission,
+  requiredPermissions: number | bigint,
+  errorText?: string,
+) {
+  const nRequiredPermissions = BigInt(requiredPermissions);
+
+  if (!hasDiscordPermissions(resolvedPermissions, nRequiredPermissions)) {
+    const requiredPermissionNames = [];
+    for (const [permissionNumber, permissionName] of permissionNumberToName.entries()) {
+      if (nRequiredPermissions & permissionNumber) {
+        requiredPermissionNames.push(permissionName);
+      }
+    }
+
+    const logs = pluginData.getPlugin(LogsPlugin);
+    logs.log(LogType.BOT_ALERT, {
+      body: `${errorText ||
+        defaultErrorText} Please ensure I have the following permissions: **${requiredPermissionNames.join(
+        "**, **",
+      )}**`.trim(),
+    });
+    return false;
+  }
+
+  return true;
+}