import { NextResponse } from 'next/server';
import { getDbPool } from '@/lib/db';
import { RowDataPacket } from 'mysql2';

// GET /api/ausgaben/stats - Get monthly statistics
export async function GET(request: Request) {
  try {
    const { searchParams } = new URL(request.url);
    const month = searchParams.get('month');
    const year = searchParams.get('year');

    if (!month || !year) {
      return NextResponse.json(
        { success: false, error: 'Month and year are required' },
        { status: 400 }
      );
    }

    const pool = getDbPool();

    // Get total ausgaben and breakdown by payment type
    const query = `
      SELECT 
        SUM(CASE WHEN Wie IN ('EC-R', 'EC-B', 'bar-R', 'bar-B', 'Ueber') THEN Wieviel ELSE 0 END) as totalAusgaben,
        SUM(CASE WHEN Wie = 'EC-R' THEN Wieviel ELSE 0 END) as ECR,
        SUM(CASE WHEN Wie = 'EC-B' THEN Wieviel ELSE 0 END) as ECB,
        SUM(CASE WHEN Wie = 'bar-R' THEN Wieviel ELSE 0 END) as barR,
        SUM(CASE WHEN Wie = 'bar-B' THEN Wieviel ELSE 0 END) as barB,
        SUM(CASE WHEN Wie = 'Einnahme' THEN Wieviel ELSE 0 END) as Einnahmen,
        SUM(CASE WHEN Wie = 'Ueber' THEN Wieviel ELSE 0 END) as Ueberweisungen
      FROM Ausgaben
      WHERE YEAR(Datum) = ? AND MONTH(Datum) = ?
    `;

    const [rows] = await pool.query<RowDataPacket[]>(query, [year, month]);

    const data = rows[0] || {
      totalAusgaben: 0,
      ECR: 0,
      ECB: 0,
      barR: 0,
      barB: 0,
      Einnahmen: 0,
      Ueberweisungen: 0,
    };

    // Convert string values from MySQL to numbers
    const parsedData = {
      totalAusgaben: parseFloat(data.totalAusgaben) || 0,
      ECR: parseFloat(data.ECR) || 0,
      ECB: parseFloat(data.ECB) || 0,
      barR: parseFloat(data.barR) || 0,
      barB: parseFloat(data.barB) || 0,
      Einnahmen: parseFloat(data.Einnahmen) || 0,
      Ueberweisungen: parseFloat(data.Ueberweisungen) || 0,
    };

    return NextResponse.json({
      success: true,
      data: parsedData,
    });
  } catch (error) {
    console.error('Database error:', error);
    return NextResponse.json(
      { success: false, error: 'Database error' },
      { status: 500 }
    );
  }
}