import { DEIncome, deIncomeTaxV2021 } from '@ktarmyshov/income-tax';
// or
import { DEIncome, deIncomeTaxV2021 } from '@ktarmyshov/income-tax/de';

// Single
const tax = deIncomeTaxV2021(2025, { income: 50000 });
// Split
const tax = deIncomeTaxV2021(2025, { income: 50000 }, { split: true });
// Custom parameters for taxation if not included in the package
const tax = deIncomeTaxV2021(
    2023,
    { income: 50000 },
    {
        split: true,
        incomeTaxParams: {
            0: {
                boundary: 10908
            },
            // Year 2023, zone 1
            // ESt = (979,18 * y + 1.400) * y
            // y = (zvE - 10.908) / 10.000
            1: {
                boundary: 15999,
                params: {
                    subtractor: 10908,
                    progression: 979.18,
                    constant: 1400
                }
            },
            // year 2023, zone 2
            // ESt = (192,59 * z + 2.397) * z + 966,53
            // z = (zvE - 15.999) / 10.000
            2: {
                boundary: 62809,
                params: {
                    subtractor: 15999,
                    progression: 192.59,
                    constant: 2397
                }
            },
            3: {
                boundary: 277825,
                params: {
                    percentage: 0.42
                }
            },
            4: {
                params: {
                    percentage: 0.45
                }
            }
        },
        solidaritySurchargeParams: {
            zeroBoundary: 17543,
            mitigationZoneBoundary: 32619,
            mitigationZoneRate: 0.119
        }
    }
);