// API endpoint для отслеживания реферальной регистрации
// POST /api/referral/track - записывает нового пользователя с реферером

import { NextRequest, NextResponse } from 'next/server';
import mysql from 'mysql2/promise';

// Database connection config
const dbConfig = {
  host: '193.168.175.128',
  user: 'marzban_user',
  password: '2CuopqFd0Y5V5n/qBM+eygOQb6aC8B8pACcdHjeVJsE=',
  database: 'marzban_prod',
};

export async function POST(request: NextRequest) {
  try {
    const body = await request.json();
    const { username, referrer_username } = body;

    if (!username) {
      return NextResponse.json(
        { success: false, error: 'Username is required' },
        { status: 400 }
      );
    }

    // Connect to database
    const connection = await mysql.createConnection(dbConfig);

    try {
      // Check if user already exists in referrals table
      const [existingRows] = await connection.query(
        'SELECT id FROM referrals WHERE username = ?',
        [username]
      );

      if ((existingRows as any[]).length > 0) {
        return NextResponse.json({
          success: false,
          error: 'User already tracked',
        });
      }

      // Insert new referral record
      await connection.query(
        'INSERT INTO referrals (username, referrer_username) VALUES (?, ?)',
        [username, referrer_username || null]
      );

      // If referrer exists, increment their referral_count
      if (referrer_username) {
        // Check if referrer exists in users table
        const [referrerRows] = await connection.query(
          'SELECT username FROM users WHERE username = ?',
          [referrer_username]
        );

        if ((referrerRows as any[]).length > 0) {
          // Update or insert referrer's stats
          await connection.query(
            `INSERT INTO referrals (username, referral_count)
             VALUES (?, 1)
             ON DUPLICATE KEY UPDATE 
               referral_count = referral_count + 1,
               updated_at = CURRENT_TIMESTAMP`,
            [referrer_username]
          );

          // Calculate bonus days
          const [statsRows] = await connection.query(
            'SELECT referral_count FROM referrals WHERE username = ?',
            [referrer_username]
          );

          const referralCount = (statsRows as any[])[0]?.referral_count || 0;
          let bonusDays = 0;

          // +7 days for each referral
          bonusDays = referralCount * 7;

          // +30 days milestone bonus for every 5 referrals
          if (referralCount >= 5) {
            const milestones = Math.floor(referralCount / 5);
            bonusDays += milestones * 30;
          }

          // Update bonus_days_earned
          await connection.query(
            'UPDATE referrals SET bonus_days_earned = ? WHERE username = ?',
            [bonusDays, referrer_username]
          );

          // Add bonus days to referrer's expire date in users table
          await connection.query(
            `UPDATE users 
             SET expire = CASE 
               WHEN expire IS NULL OR expire < UNIX_TIMESTAMP() 
               THEN UNIX_TIMESTAMP() + (? * 86400)
               ELSE expire + (7 * 86400)
             END
             WHERE username = ?`,
            [bonusDays, referrer_username]
          );

          return NextResponse.json({
            success: true,
            message: 'Referral tracked successfully',
            referrer_bonus: {
              username: referrer_username,
              new_referral_count: referralCount,
              bonus_days_added: 7,
              total_bonus_days: bonusDays,
            },
          });
        }
      }

      return NextResponse.json({
        success: true,
        message: 'User tracked without referrer',
      });
    } finally {
      await connection.end();
    }
  } catch (error) {
    console.error('Referral track error:', error);
    return NextResponse.json(
      {
        success: false,
        error: error instanceof Error ? error.message : 'Unknown error',
      },
      { status: 500 }
    );
  }
}