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');
    const typ = searchParams.get('typ');

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

    const pool = getDbPool();

    // Get total ausgaben and breakdown by payment type based on TYP
    let query: string;
    
    if (parseInt(typ) === 0) {
      // Haushalt - unterstützt beide Varianten: mit/ohne Bindestrich und Ein/Einnahme, Uber/Ueber
      query = `
        SELECT 
          SUM(CASE WHEN Wie IN ('EC-R', 'ECR', 'EC-B', 'ECB', 'bar-R', 'barR', 'bar-B', 'barB', 'Ueber', 'Uber') THEN Wieviel ELSE 0 END) as totalAusgaben,
          SUM(CASE WHEN Wie IN ('EC-R', 'ECR') THEN Wieviel ELSE 0 END) as ECR,
          SUM(CASE WHEN Wie IN ('EC-B', 'ECB') THEN Wieviel ELSE 0 END) as ECB,
          SUM(CASE WHEN Wie IN ('bar-R', 'barR') THEN Wieviel ELSE 0 END) as barR,
          SUM(CASE WHEN Wie IN ('bar-B', 'barB') THEN Wieviel ELSE 0 END) as barB,
          SUM(CASE WHEN Wie IN ('Einnahme', 'Ein') THEN Wieviel ELSE 0 END) as Einnahmen,
          SUM(CASE WHEN Wie IN ('Ueber', 'Uber') THEN Wieviel ELSE 0 END) as Ueberweisungen
        FROM Ausgaben
        WHERE YEAR(Datum) = ? AND MONTH(Datum) = ? AND TYP = 0
      `;
    } else {
      // Privat - unterstützt Uber/Ueber für Überweisung
      query = `
        SELECT 
          SUM(CASE WHEN Wie IN ('bar', 'EC', 'VISA', 'MASTER', 'Uber', 'Ueber') THEN Wieviel ELSE 0 END) as totalAusgaben,
          SUM(CASE WHEN Wie = 'bar' THEN Wieviel ELSE 0 END) as bar,
          SUM(CASE WHEN Wie = 'EC' THEN Wieviel ELSE 0 END) as EC,
          SUM(CASE WHEN Wie = 'VISA' THEN Wieviel ELSE 0 END) as VISA,
          SUM(CASE WHEN Wie = 'MASTER' THEN Wieviel ELSE 0 END) as MASTER,
          SUM(CASE WHEN Wie = 'Einnahme' THEN Wieviel ELSE 0 END) as Einnahmen,
          SUM(CASE WHEN Wie IN ('Uber', 'Ueber') THEN Wieviel ELSE 0 END) as Ueberweisungen
        FROM Ausgaben
        WHERE YEAR(Datum) = ? AND MONTH(Datum) = ? AND TYP = 1
      `;
    }

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

    const data = rows[0] || {};

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

    if (parseInt(typ) === 0) {
      parsedData.ECR = parseFloat(data.ECR) || 0;
      parsedData.ECB = parseFloat(data.ECB) || 0;
      parsedData.barR = parseFloat(data.barR) || 0;
      parsedData.barB = parseFloat(data.barB) || 0;
    } else {
      parsedData.bar = parseFloat(data.bar) || 0;
      parsedData.EC = parseFloat(data.EC) || 0;
      parsedData.VISA = parseFloat(data.VISA) || 0;
      parsedData.MASTER = parseFloat(data.MASTER) || 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 }
    );
  }
}