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

// GET /api/ausgaben - Fetch entries
export async function GET(request: Request) {
  try {
    const { searchParams } = new URL(request.url);
    const limit = searchParams.get('limit') || '10';
    const startDate = searchParams.get('startDate');
    const month = searchParams.get('month');
    const year = searchParams.get('year');
    const typ = searchParams.get('typ');

    const pool = getDbPool();

    let query = `SELECT 
      ID, Datum, Wo, Was, Kat, Wieviel, Wie, TYP,
      CASE DAYOFWEEK(Datum)
        WHEN 1 THEN 'Sonntag'
        WHEN 2 THEN 'Montag'
        WHEN 3 THEN 'Dienstag'
        WHEN 4 THEN 'Mittwoch'
        WHEN 5 THEN 'Donnerstag'
        WHEN 6 THEN 'Freitag'
        WHEN 7 THEN 'Samstag'
      END as WochTag
      FROM Ausgaben`;
    const params: any[] = [];
    const conditions: string[] = [];

    if (typ !== null && typ !== undefined) {
      conditions.push('TYP = ?');
      params.push(parseInt(typ));
    }

    if (month && year) {
      conditions.push('YEAR(Datum) = ? AND MONTH(Datum) = ?');
      params.push(year, month);
    } else if (startDate) {
      conditions.push('Datum >= ?');
      params.push(startDate);
    }

    if (conditions.length > 0) {
      query += ' WHERE ' + conditions.join(' AND ');
    }

    query += ' ORDER BY Datum DESC, ID DESC LIMIT ?';
    params.push(parseInt(limit));

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

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

// POST /api/ausgaben - Create new entry
export async function POST(request: Request) {
  try {
    const body = await request.json();
    const { Datum, Wo, Was, Kat, Wieviel, Wie, TYP } = body;

    if (!Datum || !Wo || !Was || !Wieviel || !Wie || TYP === undefined) {
      return NextResponse.json(
        { success: false, error: 'Missing required fields' },
        { status: 400 }
      );
    }

    const pool = getDbPool();

    const query = `
      INSERT INTO Ausgaben (Datum, Wo, Was, Kat, Wieviel, Wie, TYP)
      VALUES (?, ?, ?, ?, ?, ?, ?)
    `;

    const [result] = await pool.query<ResultSetHeader>(query, [
      Datum,
      Wo,
      Was,
      Kat || 'L',
      parseFloat(Wieviel),
      Wie,
      TYP,
    ]);

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