src/fed2019/Form1040.ts

   1 // Copyright 2020 Blue Static <https://www.bluestatic.org>
   2 // This program is free software licensed under the GNU General Public License,
   3 // version 3.0. The full text of the license can be found in LICENSE.txt.
   4 // SPDX-License-Identifier: GPL-3.0-only
   5
   6 import { Form, TaxReturn } from '../core';
   7 import { Line, AccumulatorLine, ComputedLine, ReferenceLine, sumLineOfForms } from '../core/Line';
   8 import { UnsupportedFeatureError } from '../core/Errors';
   9 import { clampToZero, reduceBySum } from '../core/Math';
  10
  11 import Form8606 from './Form8606';
  12 import Form8959 from './Form8959';
  13 import Form1099INT from './Form1099INT';
  14 import Form1099DIV from './Form1099DIV';
  15 import Form1099R, { Box7Code } from './Form1099R';
  16 import W2 from './W2';
  17 import Schedule1 from './Schedule1';
  18 import Schedule2 from './Schedule2';
  19 import Schedule3 from './Schedule3';
  20 import ScheduleD, { ScheduleDTaxWorksheet } from './ScheduleD';
  21
  22 export enum FilingStatus {
  23   Single = 'S',
  24   MarriedFilingSeparate = 'MFS',
  25   MarriedFilingJoint = 'MFJ',
  26 };
  27
  28 export interface Form1040Input {
  29   filingStatus: FilingStatus;
  30 };
  31
  32 export default class Form1040 extends Form<Form1040['_lines'], Form1040Input> {
  33   readonly name = '1040';
  34
  35   protected readonly _lines = {
  36     '1': new AccumulatorLine(W2, '1', 'Wages, salaries, tips, etc.'),
  37     '2a': new AccumulatorLine(Form1099INT, '8', 'Tax-exempt interest'),
  38     '2b': new AccumulatorLine(Form1099INT, '1', 'Taxable interest'),
  39     '3a': new AccumulatorLine(Form1099DIV, '1b', 'Qualified dividends'),
  40     '3b': new AccumulatorLine(Form1099DIV, '1a', 'Ordinary dividends'),
  41     '4a': new ComputedLine((tr): number => {
  42       const f1099Rs = tr.findForms(Form1099R).filter(f => !f.getValue(tr, '7').includes(Box7Code.G));
  43       return sumLineOfForms(tr, f1099Rs, '1');
  44     }),
  45     '4b': new ComputedLine((tr): number => {
  46       const f8606s = tr.findForms(Form8606);
  47       return sumLineOfForms(tr, f8606s, '15c') + sumLineOfForms(tr, f8606s, '18');
  48     }, 'IRA distributions, taxadble amount'),
  49     '4d': new ComputedLine(() => 0),
  50     // 4c and 4d are not supported
  51     // 5a and 5b are not supported
  52     '6': new ComputedLine((tr): number => {
  53       const schedD = tr.findForm(ScheduleD);
  54       if (!schedD)
  55         return 0;
  56
  57       const l6 = schedD.getValue(tr, '16');
  58       if (l6 > 0)
  59         return l6;
  60       return schedD.getValue(tr, '21');
  61     }, 'Capital gain/loss'),
  62     '7a': new ReferenceLine(Schedule1, '9', 'Other income from Schedule 1', 0),
  63
  64     '7b': new ComputedLine((tr): number => {
  65       let income = 0;
  66       income += this.getValue(tr, '1');
  67       income += this.getValue(tr, '2b');
  68       income += this.getValue(tr, '3b');
  69       income += this.getValue(tr, '4b');
  70       income += this.getValue(tr, '4d');
  71       //income += this.getValue(tr, '5b');
  72       income += this.getValue(tr, '6');
  73       income += this.getValue(tr, '7a');
  74       return income;
  75     }, 'Total income'),
  76
  77     '8a': new ReferenceLine(Schedule1, '22', 'Adjustments to income', 0),
  78
  79     '8b': new ComputedLine((tr): number => {
  80       return this.getValue(tr, '7b') - this.getValue(tr, '8a');
  81     }, 'Adjusted gross income'),
  82
  83     '9': new ComputedLine((): number => {
  84       // TODO - Itemized deductions.
  85       switch (this.filingStatus) {
  86         case FilingStatus.Single:
  87         case FilingStatus.MarriedFilingSeparate:
  88           return 12200;
  89         case FilingStatus.MarriedFilingJoint:
  90           return 24400;
  91       }
  92     }, 'Deduction'),
  93
  94     '10': new ComputedLine((tr): number => {
  95       const taxableIncome = this.getValue(tr, '8b');
  96       let use8995a = false;
  97       switch (this.filingStatus) {
  98         case FilingStatus.Single:                use8995a = taxableIncome <= 160700; break;
  99         case FilingStatus.MarriedFilingSeparate: use8995a = taxableIncome <= 160725; break;
 100         case FilingStatus.MarriedFilingJoint:    use8995a = taxableIncome <= 321400; break;
 101       };
 102       return 0;
 103     }, 'Qualified business income deduction'),
 104
 105     '11a': new ComputedLine((tr): number => {
 106       return this.getValue(tr, '9') + this.getValue(tr, '10');
 107     }),
 108     '11b': new ComputedLine((tr): number => {
 109       return clampToZero(this.getValue(tr, '8b') - this.getValue(tr, '11a'));
 110     }, 'Taxable income'),
 111
 112     '12a': new ComputedLine((tr): number => {
 113       // Not supported:
 114       // Form 8814 (election to report child's interest or dividends)
 115       // Form 4972 (relating to lump-sum distributions)
 116       const taxableIncome = this.getValue(tr, '11b');
 117
 118       if (this.getValue(tr, '3a') > 0 && !tr.findForm(ScheduleD))
 119         throw new UnsupportedFeatureError('Qualified Dividends and Captial Gains Tax Worksheet not supported, Schedule D requried');
 120
 121       const schedD = tr.findForm(ScheduleDTaxWorksheet);
 122       if (schedD)
 123         return schedD.getValue(tr, '47');
 124
 125       return computeTax(taxableIncome, this.filingStatus);
 126     }, 'Tax'),
 127
 128     '12b': new ComputedLine((tr): number => {
 129       return this.getValue(tr, '12a') + tr.getForm(Schedule2).getValue(tr, '3');
 130     }, 'Additional tax'),
 131
 132     // Not supported: 13a - child tax credit
 133
 134     '13b': new ReferenceLine(Schedule3, '7', 'Additional credits', 0),
 135
 136     '14': new ComputedLine((tr): number => {
 137       return clampToZero(this.getValue(tr, '12b') - this.getValue(tr, '13b'));
 138     }),
 139
 140     '15': new ReferenceLine(Schedule2, '10', undefined, 0),
 141
 142     '16': new ComputedLine((tr): number => {
 143       return this.getValue(tr, '14') + this.getValue(tr, '15');
 144     }, 'Total tax'),
 145
 146     '17': new ComputedLine((tr): number => {
 147       const fedTaxWithheldBoxes = [
 148         new AccumulatorLine(W2, '2'),
 149         new AccumulatorLine(Form1099R, '4'),
 150         new AccumulatorLine(Form1099DIV, '4'),
 151         new AccumulatorLine(Form1099INT, '4'),
 152       ];
 153       const withholding: number[] = fedTaxWithheldBoxes.map(b => b.value(tr));
 154
 155       let additionalMedicare = 0;
 156       const f8959 = tr.findForm(Form8959)
 157       if (f8959) {
 158         additionalMedicare = f8959.getValue(tr, '24');
 159       }
 160
 161       return reduceBySum(withholding) + additionalMedicare;
 162     }, 'Federal income tax withheld'),
 163
 164     // 18a not supported - Earned income credit (EIC)
 165     // 18b not supported - Additional child tax credit. Attach Schedule 8812
 166     // 18c not supported - American opportunity credit from Form 8863, line 8
 167     '18d': new ReferenceLine(Schedule3, '14', undefined, 0),
 168     '18e': new ComputedLine((tr): number => {
 169       // Should include 18a-18c.
 170       return this.getValue(tr, '18d');
 171     }),
 172
 173     '19': new ComputedLine((tr): number => {
 174       return this.getValue(tr, '17') + this.getValue(tr, '18e');
 175     }, 'Total payments'),
 176
 177     '20': new ComputedLine((tr): number => {
 178       return clampToZero(this.getValue(tr, '19') - this.getValue(tr, '16'));
 179     }, 'Amount overpaid'),
 180
 181     '23': new ComputedLine((tr): number => {
 182       return clampToZero(this.getValue(tr, '16') - this.getValue(tr, '19'));
 183     }, 'Amount you owe'),
 184   }
 185
 186   get filingStatus(): FilingStatus {
 187     return this.getInput('filingStatus');
 188   }
 189 };
 190
 191 export function computeTax(income: number, filingStatus: FilingStatus): number {
 192   // From https://www.irs.gov/pub/irs-drop/rp-18-57.pdf, Section 3.01 and
 193   // https://www.irs.gov/pub/irs-pdf/p17.pdf, 2019 Tax Rate Schedules (p254).
 194   const taxBrackets = {
 195     // Format is:
 196     // [ limit-of-taxable-income, marginal-rate, base-tax ]
 197     // If Income is over Row[0], pay Row[2] + (Row[1] * (Income - PreviousRow[0]))
 198     [FilingStatus.MarriedFilingJoint]: [
 199       [ 19400, 0.10, 0 ],
 200       [ 78950, 0.12, 1940 ],
 201       [ 168400, 0.22, 9086 ],
 202       [ 321450, 0.24, 28765 ],
 203       [ 408200, 0.32, 65497 ],
 204       [ 612350, 0.35, 93257 ],
 205       [ Infinity, 0.37, 164709.50 ]
 206     ],
 207     [FilingStatus.Single]: [
 208       [ 9700, 0.10, 0 ],
 209       [ 39475, 0.12, 970 ],
 210       [ 84200, 0.22, 4543 ],
 211       [ 160725, 0.24, 14382.50 ],
 212       [ 204100, 0.32, 32748.50 ],
 213       [ 510300, 0.35, 46628.50 ],
 214       [ Infinity, 0.37, 153798.50 ]
 215     ],
 216     [FilingStatus.MarriedFilingSeparate]: [
 217       [ 9700, 0.10, 0 ],
 218       [ 39475, 0.12, 970 ],
 219       [ 84200, 0.22, 4543 ],
 220       [ 160725, 0.24, 14382.50 ],
 221       [ 204100, 0.32, 32748.50 ],
 222       [ 306175, 0.35, 46628.50 ],
 223       [ Infinity, 0.37, 82354.75 ]
 224     ]
 225   }[filingStatus];
 226
 227   let i = 0;
 228   while (taxBrackets[i][0] < income)
 229     ++i;
 230
 231   const bracket = taxBrackets[i];
 232   const bracketStart = i == 0 ? 0 : taxBrackets[i - 1][0];
 233
 234   return ((income - bracketStart) * bracket[1]) + bracket[2];
 235 };