feat: Implement NextAuth authentication with credentials, database and JSON fallback, including admin seeding and password management.

src/features/auth/logic/auth-logic.ts

@@ -1,4 +1,15 @@
 import { scryptSync, randomBytes, timingSafeEqual } from "crypto";
+import fs from "fs";
+import path from "path";
+
+const USERS_JSON_PATH = path.join(process.cwd(), "data", "users.json");
+
+export interface UserJson {
+    id: string;
+    username: string;
+    passwordHash: string;
+    role: string;
+}
 
 /**
  * Hashes a password using scrypt.
@@ -26,3 +37,40 @@ export function verifyPassword(password: string, storedHash: string): boolean {
         return false;
     }
 }
+
+/**
+ * Reads users from local JSON fallback.
+ */
+export function getFallbackUsers(): UserJson[] {
+    try {
+        if (!fs.existsSync(USERS_JSON_PATH)) {
+            // Initial seed if file doesn't exist
+            const defaultAdmin: UserJson = {
+                id: "0",
+                username: "admin",
+                passwordHash: hashPassword("admin"),
+                role: "admin"
+            };
+            saveFallbackUsers([defaultAdmin]);
+            return [defaultAdmin];
+        }
+        const data = fs.readFileSync(USERS_JSON_PATH, "utf-8");
+        return JSON.parse(data);
+    } catch (e) {
+        console.error("[AUTH] Error reading users.json:", e);
+        return [];
+    }
+}
+
+/**
+ * Saves users to local JSON fallback.
+ */
+export function saveFallbackUsers(users: UserJson[]) {
+    try {
+        const dir = path.dirname(USERS_JSON_PATH);
+        if (!fs.existsSync(dir)) fs.mkdirSync(dir, { recursive: true });
+        fs.writeFileSync(USERS_JSON_PATH, JSON.stringify(users, null, 2));
+    } catch (e) {
+        console.error("[AUTH] Error writing users.json:", e);
+    }
+}

src/features/auth/logic/seed-admin.ts

@@ -1,6 +1,6 @@
 import { db } from "@/db";
 import { users } from "@/db/schema";
-import { hashPassword } from "./auth-logic";
+import { hashPassword, getFallbackUsers, saveFallbackUsers } from "./auth-logic";
 import { count, eq, sql } from "drizzle-orm";
 
 /**
@@ -9,13 +9,23 @@ import { count, eq, sql } from "drizzle-orm";
  * Also ensures the table exists (auto-repair).
  */
 export async function ensureAdminExists() {
-    try {
-        console.log("[AUTH] Testing database connection...");
-        await db.execute(sql`SELECT 1`);
-        console.log("[AUTH] Database connection OK.");
+    // 1. Always ensure local JSON fallback has at least one admin
+    const fallbackUsers = getFallbackUsers();
+    if (fallbackUsers.length === 0) {
+        console.log("[AUTH] Initializing local JSON fallback with admin/admin...");
+        saveFallbackUsers([{
+            id: "0",
+            username: "admin",
+            passwordHash: hashPassword("admin"),
+            role: "admin"
+        }]);
+    }
 
-        // 1. Auto-repair: Ensure table exists (Fallback if db-init failed)
-        console.log("[AUTH] Checking/Creating users table...");
+    try {
+        console.log("[AUTH] Testing database connection for seeding...");
+        await db.execute(sql`SELECT 1`);
+
+        // 2. Auto-repair: Ensure table exists
         await db.execute(sql`
             CREATE TABLE IF NOT EXISTS "users" (
                 id SERIAL PRIMARY KEY,
@@ -25,32 +35,24 @@ export async function ensureAdminExists() {
                 created_at TIMESTAMP DEFAULT NOW()
             );
         `);
-        console.log("[AUTH] users table verified/created.");
 
+        // 3. Sync admin to DB
         const adminUser = await db.select()
             .from(users)
             .where(eq(users.username, "admin"))
             .limit(1);
 
         if (adminUser.length === 0) {
-            console.log("[AUTH] Admin user not found. Seeding default (admin/admin)...");
+            console.log("[AUTH] Seeding admin to DB...");
             await db.insert(users).values({
                 username: "admin",
                 passwordHash: hashPassword("admin"),
                 role: "admin"
             });
-            console.log("[AUTH] Default admin seeded successfully.");
             return true;
-        } else {
-            console.log("[AUTH] Admin user already exists.");
         }
     } catch (err: any) {
-        console.error("[AUTH] !!! CRITICAL DATABASE ERROR !!!");
-        console.error("- Message:", err.message);
-        console.error("- PG Code:", err.code);
-        console.error("- Detail:", err.detail);
-        console.error("- Hint:", err.hint);
-        if (err.internalQuery) console.error("- Query:", err.internalQuery);
+        console.warn("[AUTH] Database seeding failed (expected if DB not configured yet):", err.message);
     }
     return false;
 }