feat(admission): add scheduled group access

apps/web/src/lib/admission-settings.ts

@@ -2,36 +2,53 @@ export interface AdmissionMessages {
   registrationMessage: string;
   groupAccessDeniedMessage: string;
   vpnDeniedMessage: string;
+  scheduledAccessDeniedMessage: string;
 }
 
+export type AdmissionDenialReason =
+  | "not_registered"
+  | "group_access_disabled"
+  | "schedule_disallowed"
+  | "anonymized_network_disallowed";
+
 export const DEFAULT_ADMISSION_MESSAGES: AdmissionMessages = {
   registrationMessage: "Please register your Minecraft account before joining.",
   groupAccessDeniedMessage: "Your account group does not currently have server access. Contact a host if you believe this is a mistake.",
   vpnDeniedMessage: "VPN, proxy, and Tor connections are not allowed. Contact a host to request an exception.",
+  scheduledAccessDeniedMessage: "Your group is only allowed access from {next_start} to {next_end}.",
 } as const;
 
-export function admissionDenialMessage(
-  reason: "not_registered" | "group_access_disabled" | "anonymized_network_disallowed",
-  messages: AdmissionMessages,
-) {
+export function admissionDenialMessage(reason: AdmissionDenialReason, messages: AdmissionMessages) {
   if (reason === "not_registered") return messages.registrationMessage;
   if (reason === "group_access_disabled") return messages.groupAccessDeniedMessage;
+  if (reason === "schedule_disallowed") return messages.scheduledAccessDeniedMessage;
   return messages.vpnDeniedMessage;
 }
 
 const CONTROL_CHARACTERS = /[\u0000-\u001f\u007f]/;
+const TEMPLATE_VARIABLE = /\{([a-z_]+)\}/g;
+const COMMON_VARIABLES = new Set(["player", "group"]);
+const SCHEDULE_VARIABLES = new Set(["player", "group", "next_start", "next_end"]);
 
-function messageValue(formData: FormData, name: string) {
+type MessageName = keyof AdmissionMessages;
+
+function messageValue(formData: FormData, name: MessageName, allowedVariables: Set<string>) {
   const value = String(formData.get(name) ?? "").trim();
-  return value.length >= 10 && value.length <= 500 && !CONTROL_CHARACTERS.test(value)
-    ? value
-    : null;
+  if (value.length < 10 || value.length > 500 || CONTROL_CHARACTERS.test(value)) return null;
+  const withoutVariables = value.replace(TEMPLATE_VARIABLE, (match, variable: string) =>
+    allowedVariables.has(variable) ? "" : match);
+  return /[{}]/.test(withoutVariables) ? null : value;
 }
 
 export function parseAdmissionMessages(formData: FormData) {
-  const registrationMessage = messageValue(formData, "registrationMessage");
-  const groupAccessDeniedMessage = messageValue(formData, "groupAccessDeniedMessage");
-  const vpnDeniedMessage = messageValue(formData, "vpnDeniedMessage");
-  if (!registrationMessage || !groupAccessDeniedMessage || !vpnDeniedMessage) return null;
-  return { registrationMessage, groupAccessDeniedMessage, vpnDeniedMessage };
+  const registrationMessage = messageValue(formData, "registrationMessage", COMMON_VARIABLES);
+  const groupAccessDeniedMessage = messageValue(formData, "groupAccessDeniedMessage", COMMON_VARIABLES);
+  const vpnDeniedMessage = messageValue(formData, "vpnDeniedMessage", COMMON_VARIABLES);
+  const scheduledAccessDeniedMessage = messageValue(formData, "scheduledAccessDeniedMessage", SCHEDULE_VARIABLES);
+  if (!registrationMessage || !groupAccessDeniedMessage || !vpnDeniedMessage || !scheduledAccessDeniedMessage) return null;
+  return { registrationMessage, groupAccessDeniedMessage, vpnDeniedMessage, scheduledAccessDeniedMessage };
+}
+
+export function renderAdmissionMessage(template: string, variables: Record<string, string>) {
+  return template.replace(TEMPLATE_VARIABLE, (match, variable: string) => variables[variable] ?? match);
 }