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 ComputedLine((tr): number => {
  38       const value = (new AccumulatorLine(Form1099INT, '8')).value(tr) +
  39                     (new AccumulatorLine(Form1099DIV, '11')).value(tr);
  40       return value;
  41     }, 'Tax-exempt interest'),
  42     '2b': new AccumulatorLine(Form1099INT, '1', 'Taxable interest'),
  43     '3a': new AccumulatorLine(Form1099DIV, '1b', 'Qualified dividends'),
  44     '3b': new AccumulatorLine(Form1099DIV, '1a', 'Ordinary dividends'),
  45     '4a': new ComputedLine((tr): number => {
  46       const f1099Rs = tr.findForms(Form1099R).filter(f => !f.getValue(tr, '7').includes(Box7Code.G));
  47       return sumLineOfForms(tr, f1099Rs, '1');
  48     }),
  49     '4b': new ComputedLine((tr): number => {
  50       const f8606s = tr.findForms(Form8606);
  51       return sumLineOfForms(tr, f8606s, '15c') + sumLineOfForms(tr, f8606s, '18');
  52     }, 'IRA distributions, taxadble amount'),
  53     '4d': new ComputedLine(() => 0),
  54     // 4c and 4d are not supported
  55     // 5a and 5b are not supported
  56     '6': new ComputedLine((tr): number => {
  57       const schedD = tr.findForm(ScheduleD);
  58       if (!schedD)
  59         return 0;
  60
  61       const l6 = schedD.getValue(tr, '16');
  62       if (l6 > 0)
  63         return l6;
  64       return schedD.getValue(tr, '21');
  65     }, 'Capital gain/loss'),
  66     '7a': new ReferenceLine(Schedule1, '9', 'Other income from Schedule 1', 0),
  67
  68     '7b': new ComputedLine((tr): number => {
  69       let income = 0;
  70       income += this.getValue(tr, '1');
  71       income += this.getValue(tr, '2b');
  72       income += this.getValue(tr, '3b');
  73       income += this.getValue(tr, '4b');
  74       income += this.getValue(tr, '4d');
  75       //income += this.getValue(tr, '5b');
  76       income += this.getValue(tr, '6');
  77       income += this.getValue(tr, '7a');
  78       return income;
  79     }, 'Total income'),
  80
  81     '8a': new ReferenceLine(Schedule1, '22', 'Adjustments to income', 0),
  82
  83     '8b': new ComputedLine((tr): number => {
  84       return this.getValue(tr, '7b') - this.getValue(tr, '8a');
  85     }, 'Adjusted gross income'),
  86
  87     '9': new ComputedLine((): number => {
  88       // TODO - Itemized deductions.
  89       switch (this.filingStatus) {
  90         case FilingStatus.Single:
  91         case FilingStatus.MarriedFilingSeparate:
  92           return 12200;
  93         case FilingStatus.MarriedFilingJoint:
  94           return 24400;
  95       }
  96     }, 'Deduction'),
  97
  98     '10': new ComputedLine((tr): number => {
  99       const taxableIncome = this.getValue(tr, '8b');
 100       let use8995a = false;
 101       switch (this.filingStatus) {
 102         case FilingStatus.Single:                use8995a = taxableIncome <= 160700; break;
 103         case FilingStatus.MarriedFilingSeparate: use8995a = taxableIncome <= 160725; break;
 104         case FilingStatus.MarriedFilingJoint:    use8995a = taxableIncome <= 321400; break;
 105       };
 106       return 0;
 107     }, 'Qualified business income deduction'),
 108
 109     '11a': new ComputedLine((tr): number => {
 110       return this.getValue(tr, '9') + this.getValue(tr, '10');
 111     }),
 112     '11b': new ComputedLine((tr): number => {
 113       return clampToZero(this.getValue(tr, '8b') - this.getValue(tr, '11a'));
 114     }, 'Taxable income'),
 115
 116     '12a': new ComputedLine((tr): number => {
 117       // Not supported:
 118       // Form 8814 (election to report child's interest or dividends)
 119       // Form 4972 (relating to lump-sum distributions)
 120       const taxableIncome = this.getValue(tr, '11b');
 121
 122       if (this.getValue(tr, '3a') > 0 && !tr.findForm(ScheduleD))
 123         throw new UnsupportedFeatureError('Qualified Dividends and Captial Gains Tax Worksheet not supported, Schedule D requried');
 124
 125       const schedD = tr.findForm(ScheduleDTaxWorksheet);
 126       if (schedD)
 127         return schedD.getValue(tr, '47');
 128
 129       return computeTax(taxableIncome, this.filingStatus);
 130     }, 'Tax'),
 131
 132     '12b': new ComputedLine((tr): number => {
 133       return this.getValue(tr, '12a') + tr.getForm(Schedule2).getValue(tr, '3');
 134     }, 'Additional tax'),
 135
 136     // Not supported: 13a - child tax credit
 137
 138     '13b': new ReferenceLine(Schedule3, '7', 'Additional credits', 0),
 139
 140     '14': new ComputedLine((tr): number => {
 141       return clampToZero(this.getValue(tr, '12b') - this.getValue(tr, '13b'));
 142     }),
 143
 144     '15': new ReferenceLine(Schedule2, '10', undefined, 0),
 145
 146     '16': new ComputedLine((tr): number => {
 147       return this.getValue(tr, '14') + this.getValue(tr, '15');
 148     }, 'Total tax'),
 149
 150     '17': new ComputedLine((tr): number => {
 151       const fedTaxWithheldBoxes = [
 152         new AccumulatorLine(W2, '2'),
 153         new AccumulatorLine(Form1099R, '4'),
 154         new AccumulatorLine(Form1099DIV, '4'),
 155         new AccumulatorLine(Form1099INT, '4'),
 156       ];
 157       const withholding: number[] = fedTaxWithheldBoxes.map(b => b.value(tr));
 158
 159       let additionalMedicare = 0;
 160       const f8959 = tr.findForm(Form8959)
 161       if (f8959) {
 162         additionalMedicare = f8959.getValue(tr, '24');
 163       }
 164
 165       return reduceBySum(withholding) + additionalMedicare;
 166     }, 'Federal income tax withheld'),
 167
 168     // 18a not supported - Earned income credit (EIC)
 169     // 18b not supported - Additional child tax credit. Attach Schedule 8812
 170     // 18c not supported - American opportunity credit from Form 8863, line 8
 171     '18d': new ReferenceLine(Schedule3, '14', undefined, 0),
 172     '18e': new ComputedLine((tr): number => {
 173       // Should include 18a-18c.
 174       return this.getValue(tr, '18d');
 175     }),
 176
 177     '19': new ComputedLine((tr): number => {
 178       return this.getValue(tr, '17') + this.getValue(tr, '18e');
 179     }, 'Total payments'),
 180
 181     '20': new ComputedLine((tr): number => {
 182       return clampToZero(this.getValue(tr, '19') - this.getValue(tr, '16'));
 183     }, 'Amount overpaid'),
 184
 185     '23': new ComputedLine((tr): number => {
 186       return clampToZero(this.getValue(tr, '16') - this.getValue(tr, '19'));
 187     }, 'Amount you owe'),
 188   }
 189
 190   get filingStatus(): FilingStatus {
 191     return this.getInput('filingStatus');
 192   }
 193 };
 194
 195 export function computeTax(income: number, filingStatus: FilingStatus): number {
 196   // From https://www.irs.gov/pub/irs-drop/rp-18-57.pdf, Section 3.01 and
 197   // https://www.irs.gov/pub/irs-pdf/p17.pdf, 2019 Tax Rate Schedules (p254).
 198   const taxBrackets = {
 199     // Format is:
 200     // [ limit-of-taxable-income, marginal-rate, base-tax ]
 201     // If Income is over Row[0], pay Row[2] + (Row[1] * (Income - PreviousRow[0]))
 202     [FilingStatus.MarriedFilingJoint]: [
 203       [ 19400, 0.10, 0 ],
 204       [ 78950, 0.12, 1940 ],
 205       [ 168400, 0.22, 9086 ],
 206       [ 321450, 0.24, 28765 ],
 207       [ 408200, 0.32, 65497 ],
 208       [ 612350, 0.35, 93257 ],
 209       [ Infinity, 0.37, 164709.50 ]
 210     ],
 211     [FilingStatus.Single]: [
 212       [ 9700, 0.10, 0 ],
 213       [ 39475, 0.12, 970 ],
 214       [ 84200, 0.22, 4543 ],
 215       [ 160725, 0.24, 14382.50 ],
 216       [ 204100, 0.32, 32748.50 ],
 217       [ 510300, 0.35, 46628.50 ],
 218       [ Infinity, 0.37, 153798.50 ]
 219     ],
 220     [FilingStatus.MarriedFilingSeparate]: [
 221       [ 9700, 0.10, 0 ],
 222       [ 39475, 0.12, 970 ],
 223       [ 84200, 0.22, 4543 ],
 224       [ 160725, 0.24, 14382.50 ],
 225       [ 204100, 0.32, 32748.50 ],
 226       [ 306175, 0.35, 46628.50 ],
 227       [ Infinity, 0.37, 82354.75 ]
 228     ]
 229   }[filingStatus];
 230
 231   let i = 0;
 232   while (taxBrackets[i][0] < income)
 233     ++i;
 234
 235   const bracket = taxBrackets[i];
 236   const bracketStart = i == 0 ? 0 : taxBrackets[i - 1][0];
 237
 238   return ((income - bracketStart) * bracket[1]) + bracket[2];
 239 };