item transfer, item to buy other items, item income, unbuyable items

util.ts

@@ -1,6 +1,9 @@
 import type { ChatInputCommandInteraction, GuildMember } from "discord.js";
+import { ActionRowBuilder, ButtonBuilder, ButtonStyle } from "discord.js";
 import type { UpdateResult } from "mongodb";
 
+import config from "./config.json";
+
 export function did_update(result: UpdateResult): boolean {
   return result.modifiedCount > 0;
 }
@@ -8,3 +11,33 @@ export function did_update(result: UpdateResult): boolean {
 export function has_role(interaction: ChatInputCommandInteraction, role_id: string): boolean {
   return (interaction.member as GuildMember).roles.cache.some((r) => r.id === role_id);
 }
+
+export function is_admin(interaction: ChatInputCommandInteraction): boolean {
+  return has_role(interaction, config.admin_role);
+}
+
+//calculate payout
+export function calc_role_income_claim(last_claim: number, hours: number, income: number): [number, number] {
+  const hours_since = (Date.now() - last_claim) / (60 * 60 * 1000);
+  const cycles = Math.floor(hours_since / hours);
+  return [cycles * income, cycles];
+}
+
+export function gen_action_row(page: number, pages: number) {
+  let action_row = new ActionRowBuilder<ButtonBuilder>();
+  let action_prev = new ButtonBuilder()
+    .setCustomId(String(page - 1))
+    .setLabel("Prev")
+    .setEmoji("⬅️")
+    .setStyle(ButtonStyle.Primary)
+    .setDisabled(page - 1 === 0);
+  let action_next = new ButtonBuilder()
+    .setCustomId(String(page + 1))
+    .setLabel("Next")
+    .setEmoji("➡️")
+    .setStyle(ButtonStyle.Primary)
+    .setDisabled(page + 1 > pages);
+  action_row.addComponents(action_prev, action_next);
+  return action_row;
+}
+