feat: Implement user enrollment interaction to assign a random class role and add new role configurations.

src/modules/user/enrollment.interaction.ts

@@ -0,0 +1,94 @@
+import { ButtonInteraction, MessageFlags } from "discord.js";
+import { config } from "@/lib/config";
+import { createErrorEmbed } from "@/lib/embeds";
+import { classService } from "@modules/class/class.service";
+import { userService } from "@modules/user/user.service";
+
+export async function handleEnrollmentInteraction(interaction: ButtonInteraction) {
+    if (!interaction.inCachedGuild()) {
+        await interaction.reply({ content: "This action can only be performed in a server.", flags: MessageFlags.Ephemeral });
+        return;
+    }
+
+    const { studentRole, visitorRole } = config;
+
+    if (!studentRole || !visitorRole) {
+        await interaction.reply({
+            embeds: [createErrorEmbed("No student or visitor role configured for enrollment.", "Configuration Error")],
+            flags: MessageFlags.Ephemeral
+        });
+        return;
+    }
+
+    try {
+        // 1. Ensure user exists in DB and check current enrollment status
+        const user = await userService.getOrCreateUser(interaction.user.id, interaction.user.username);
+
+        // Check DB enrollment
+        if (user.class) {
+            await interaction.reply({
+                embeds: [createErrorEmbed("You are already enrolled in a class.", "Enrollment Failed")],
+                flags: MessageFlags.Ephemeral
+            });
+            return;
+        }
+
+        const member = interaction.member;
+
+        // Check Discord role enrollment (Double safety)
+        if (member.roles.cache.has(studentRole)) {
+            await interaction.reply({
+                embeds: [createErrorEmbed("You already have the student role.", "Enrollment Failed")],
+                flags: MessageFlags.Ephemeral
+            });
+            return;
+        }
+
+        // 2. Get available classes
+        const allClasses = await classService.getAllClasses();
+        const validClasses = allClasses.filter(c => c.roleId);
+
+        if (validClasses.length === 0) {
+            await interaction.reply({
+                embeds: [createErrorEmbed("No classes with specified roles found in database.", "Configuration Error")],
+                flags: MessageFlags.Ephemeral
+            });
+            return;
+        }
+
+        // 3. Pick random class
+        const selectedClass = validClasses[Math.floor(Math.random() * validClasses.length)]!;
+        const classRoleId = selectedClass.roleId!;
+
+        // Check if the role exists in the guild
+        const classRole = interaction.guild.roles.cache.get(classRoleId);
+        if (!classRole) {
+            await interaction.reply({
+                embeds: [createErrorEmbed(`The configured role ID \`${classRoleId}\` for class **${selectedClass.name}** does not exist in this server.`, "Configuration Error")],
+                flags: MessageFlags.Ephemeral
+            });
+            return;
+        }
+
+        // 4. Perform Enrollment Actions
+
+        await member.roles.remove(visitorRole);
+        await member.roles.add(studentRole);
+        await member.roles.add(classRole);
+
+        // Persist to DB
+        await classService.assignClass(user.id.toString(), selectedClass.id);
+
+        await interaction.reply({
+            content: `🎉 You have been successfully enrolled! You are now a member of **${selectedClass.name}** and received the **${classRole.name}** role.`,
+            flags: MessageFlags.Ephemeral
+        });
+
+    } catch (error) {
+        console.error("Enrollment error:", error);
+        await interaction.reply({
+            embeds: [createErrorEmbed("An unexpected error occurred during enrollment. Please contact an administrator.", "System Error")],
+            flags: MessageFlags.Ephemeral
+        });
+    }
+}