import { NextRequest, NextResponse } from "next/server";
import { Pool } from "pg";
import { requireAdmin, requireSuperAdmin } from "@/lib/auth-utils";

const pool = new Pool({
  connectionString: process.env.DATABASE_URL,
});

// GET /api/admin/users - List all users
export async function GET(request: NextRequest) {
  const { error } = await requireAdmin();
  if (error) return error;

  try {
    const searchParams = request.nextUrl.searchParams;
    const search = searchParams.get("search") || "";
    const role = searchParams.get("role") || "";
    const status = searchParams.get("status") || "";
    const page = parseInt(searchParams.get("page") || "1");
    const limit = parseInt(searchParams.get("limit") || "20");
    const offset = (page - 1) * limit;

    let query = `
      SELECT 
        id, name, email, email_verified, image, role, banned, 
        banned_reason, ban_expires, requires_setup, created_at, updated_at
      FROM "user"
      WHERE 1=1
    `;
    const params: (string | number)[] = [];
    let paramIndex = 1;

    if (search) {
      query += ` AND (name ILIKE $${paramIndex} OR email ILIKE $${paramIndex})`;
      params.push(`%${search}%`);
      paramIndex++;
    }

    if (role) {
      query += ` AND role = $${paramIndex}`;
      params.push(role);
      paramIndex++;
    }

    if (status === "active") {
      query += ` AND (banned = false OR banned IS NULL)`;
    } else if (status === "banned") {
      query += ` AND banned = true`;
    }

    // Get total count
    const countQuery = query.replace(
      /SELECT[\s\S]*?FROM/,
      "SELECT COUNT(*) as total FROM"
    );
    const countResult = await pool.query(countQuery, params);
    const total = parseInt(countResult.rows[0].total);

    // Add pagination
    query += ` ORDER BY created_at DESC LIMIT $${paramIndex} OFFSET $${paramIndex + 1}`;
    params.push(limit, offset);

    const result = await pool.query(query, params);

    return NextResponse.json({
      users: result.rows,
      pagination: {
        page,
        limit,
        total,
        totalPages: Math.ceil(total / limit),
      },
    });
  } catch (error) {
    console.error("Error fetching users:", error);
    return NextResponse.json(
      { error: "Failed to fetch users" },
      { status: 500 }
    );
  }
}

// POST /api/admin/users - Create a new user
export async function POST(request: NextRequest) {
  const { session, error } = await requireSuperAdmin();
  if (error) return error;

  try {
    const body = await request.json();
    const { name, email, role = "user" } = body;

    if (!name || !email) {
      return NextResponse.json(
        { error: "Name and email are required" },
        { status: 400 }
      );
    }

    // Check if user already exists
    const existingUser = await pool.query(
      'SELECT id FROM "user" WHERE email = $1',
      [email]
    );

    if (existingUser.rows.length > 0) {
      return NextResponse.json(
        { error: "User with this email already exists" },
        { status: 409 }
      );
    }

    // Create the user
    const id = crypto.randomUUID();
    const result = await pool.query(
      `INSERT INTO "user" (id, name, email, role, email_verified, created_at, updated_at)
       VALUES ($1, $2, $3, $4, false, NOW(), NOW())
       RETURNING id, name, email, role, email_verified, created_at`,
      [id, name, email, role]
    );

    return NextResponse.json({ user: result.rows[0] }, { status: 201 });
  } catch (error) {
    console.error("Error creating user:", error);
    return NextResponse.json(
      { error: "Failed to create user" },
      { status: 500 }
    );
  }
}