feat: auth

api/src/app/services/auth.service.ts

@@ -0,0 +1,78 @@
+import { FastifyInstance } from "fastify";
+import { JwtPayload, User } from "@library/shared-types";
+import { PrismaClient } from "../../generated/prisma";
+
+export class AuthService {
+  private prisma: PrismaClient;
+
+  constructor(private readonly app: FastifyInstance) {
+    this.prisma = new PrismaClient();
+  }
+
+  /**
+   * Generate JWT token for user.
+   */
+  async generateToken(user: User): Promise<string> {
+    const payload: JwtPayload = {
+      sub: user.id,
+      email: user.email,
+      username: user.username,
+      isAdmin: user.isAdmin,
+    };
+
+    return this.app.jwt.sign(payload, {
+      expiresIn: "7d",
+    });
+  }
+
+  /**
+   * Verify JWT token.
+   */
+  async verifyToken(token: string): Promise<JwtPayload> {
+    return this.app.jwt.verify(token) as JwtPayload;
+  }
+
+  /**
+   * Create or update user from Discord OAuth data.
+   */
+  async createOrUpdateUserFromDiscord(discordData: DiscordUser): Promise<User> {
+    const avatarUrl = discordData.avatar
+      ? `https://cdn.discordapp.com/avatars/${discordData.id}/${discordData.avatar}.png`
+      : undefined;
+
+    // Upsert user in database
+    const dbUser = await this.prisma.user.upsert({
+      where: {
+        discordId: discordData.id,
+      },
+      create: {
+        discordId: discordData.id,
+        username: discordData.username,
+        email: discordData.email,
+        avatar: avatarUrl,
+        isAdmin: discordData.id === process.env.ADMIN_DISCORD_ID,
+      },
+      update: {
+        username: discordData.username,
+        email: discordData.email,
+        avatar: avatarUrl,
+      },
+    });
+
+    return {
+      id: dbUser.id,
+      discordId: dbUser.discordId,
+      username: dbUser.username,
+      email: dbUser.email,
+      avatarUrl: dbUser.avatar || undefined,
+      isAdmin: dbUser.isAdmin,
+    };
+  }
+}
+
+interface DiscordUser {
+  id: string;
+  username: string;
+  email: string;
+  avatar?: string;
+}