Salary module (#245)
* feat: implement salary module with personnummer encryption, salary entries, tax tables, and AGI tracking - Added personnummer encryption and decryption functions for secure storage. - Created salary entries handling for journal entries including gross salary, tax withholding, and employer contributions. - Implemented tax table lookup functionality for calculating tax amounts based on monthly income. - Developed SQL migration for salary module including tables for payroll configuration, tax rates, employees, salary runs, salary run employees, salary line items, and AGI declarations. - Established row-level security policies for all new tables to ensure company-scoped access. * feat: add salary calculation modules for 2026 - Implemented engångsskatt calculation for one-time payments with tax brackets. - Added löneväxling functionality for salary sacrifice to pension, including employer savings and warnings. - Created pain.001 generator for salary batch payments in compliance with Swedish banking standards. - Developed PDF template for payslips, including detailed breakdowns and employer costs. - Generated seed data for Swedish tax tables for 2026, including SQL insert statements. - Implemented traktamente calculations for per diem and mileage allowances, adhering to Skatteverket regulations. - Added seed script for populating tax tables in the database. * feat: Update meal reduction percentages in traktamente calculation fix: Remove obsolete seed script for 2026 tax tables feat: Extend SalaryRunStatus type to include 'corrected' status feat: Implement KU10 XML generation endpoint for annual employee income statements feat: Add endpoint for creating corrections to booked salary runs feat: Implement endpoint for sending payslip PDFs to employees feat: Create KU10 XML generator for annual reporting feat: Add salary transaction matcher for auto-linking bank transactions to salary entries chore: Add database migration for salary correction support * feat: replace select elements with custom Select component for employment and salary types * feat: enhance salary calculations with pension entry and avgifter category support
This commit is contained in:
Mattsson
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import type { PayrollConfig } from './payroll-config'
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import type { TaxTableRate } from './tax-tables'
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import { lookupTaxAmount, calculateJamkningTax, calculateSidoinkomstTax } from './tax-tables'
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import { calculateAgeAtYearStart, decryptPersonnummer } from './personnummer'
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import type { SalaryLineItemType } from '@/types'
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// ============================================================
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// Types
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// ============================================================
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export interface SalaryCalculationInput {
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/** Employee data */
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employmentType: 'employee' | 'company_owner' | 'board_member'
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salaryType: 'monthly' | 'hourly'
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monthlySalary: number
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hourlyRate?: number
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hoursWorked?: number
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employmentDegree: number // 1-100
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/** Tax */
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taxTableNumber: number | null
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taxColumn: number
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isSidoinkomst: boolean
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jamkningPercentage: number | null
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jamkningValidFrom: string | null
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jamkningValidTo: string | null
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fSkattStatus: string
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/** Age (from personnummer) */
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personnummer: string // encrypted — will be decrypted for age calc
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paymentDate: string
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/** Vacation */
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vacationRule: 'procentregeln' | 'sammaloneregeln'
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vacationDaysPerYear: number
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semestertillaggRate: number
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/** Växa-stöd */
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vaxaStodEligible: boolean
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vaxaStodStart: string | null
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vaxaStodEnd: string | null
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/** Line items */
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lineItems: CalculationLineItem[]
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}
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export interface CalculationLineItem {
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itemType: SalaryLineItemType
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amount: number
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isTaxable: boolean
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isAvgiftBasis: boolean
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isVacationBasis: boolean
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isGrossDeduction: boolean
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isNetDeduction: boolean
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}
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export interface CalculationStep {
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label: string
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formula: string
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input: Record<string, number | string>
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output: number
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}
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export interface SalaryCalculationResult {
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grossSalary: number
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grossDeductions: number
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benefitValues: number
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taxableIncome: number
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taxWithheld: number
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netDeductions: number
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netSalary: number
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avgifterRate: number
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avgifterAmount: number
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avgifterBasis: number
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avgifterCategory: AvgifterCalculation['category']
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vacationAccrual: number
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vacationAccrualAvgifter: number
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totalEmployerCost: number
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steps: CalculationStep[]
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}
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export interface AvgifterCalculation {
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rate: number
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amount: number
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basis: number
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category: 'standard' | 'reduced_65plus' | 'youth' | 'vaxa_stod' | 'exempt'
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steps: CalculationStep[]
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}
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// ============================================================
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// Rounding helper
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// ============================================================
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function r(x: number): number {
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return Math.round(x * 100) / 100
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}
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// ============================================================
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// Main calculation
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// ============================================================
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/**
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* Calculate salary for one employee in a salary run.
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* Follows the legally mandated processing order:
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* 1. Base salary
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* 2. Add additions (overtime, bonus, etc.)
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* 3. Subtract absence deductions
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* 4. Apply bruttolöneavdrag (MUST be before tax)
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* 5. Add förmånsvärden to tax base
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* 6. Tax withholding
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* 7. Net salary
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* 8. Employer contributions (avgifter)
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* 9. Vacation accrual
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* 10. Avgifter on vacation accrual
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*/
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export function calculateSalary(
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input: SalaryCalculationInput,
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config: PayrollConfig,
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taxRates: TaxTableRate[]
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): SalaryCalculationResult {
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const steps: CalculationStep[] = []
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// ─── Step 1: Base salary ───
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let baseSalary: number
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if (input.salaryType === 'monthly') {
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baseSalary = r(input.monthlySalary * (input.employmentDegree / 100))
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steps.push({
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label: 'Grundlön',
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formula: 'monthly_salary × (employment_degree / 100)',
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input: { monthly_salary: input.monthlySalary, employment_degree: input.employmentDegree },
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output: baseSalary,
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})
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} else {
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const hours = input.hoursWorked || 0
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const rate = input.hourlyRate || 0
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baseSalary = r(rate * hours)
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steps.push({
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label: 'Grundlön (timavlönad)',
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formula: 'hourly_rate × hours_worked',
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input: { hourly_rate: rate, hours_worked: hours },
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output: baseSalary,
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})
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}
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// ─── Step 2: Add additions ───
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const additions = input.lineItems.filter(
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li => ['overtime', 'bonus', 'commission'].includes(li.itemType) && li.amount > 0
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)
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const totalAdditions = r(additions.reduce((sum, li) => sum + li.amount, 0))
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if (totalAdditions > 0) {
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steps.push({
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label: 'Tillägg (övertid, bonus, provision)',
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formula: 'sum(additions)',
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input: { count: additions.length },
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output: totalAdditions,
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})
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}
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// ─── Step 3: Subtract absence deductions ───
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const absenceItems = input.lineItems.filter(
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li => ['sick_karens', 'sick_day2_14', 'sick_day15_plus', 'vab', 'parental_leave', 'vacation'].includes(li.itemType)
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)
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const totalAbsence = r(absenceItems.reduce((sum, li) => sum + li.amount, 0))
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if (totalAbsence !== 0) {
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steps.push({
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label: 'Frånvaro (sjuk, VAB, semester, föräldraledig)',
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formula: 'sum(absence_items)',
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input: { count: absenceItems.length },
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output: totalAbsence,
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})
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}
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// ─── Step 4: Bruttolöneavdrag (MUST be before tax) ───
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const grossDeductionItems = input.lineItems.filter(li => li.isGrossDeduction)
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const totalGrossDeductions = r(Math.abs(grossDeductionItems.reduce((sum, li) => sum + li.amount, 0)))
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if (totalGrossDeductions > 0) {
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steps.push({
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label: 'Bruttolöneavdrag',
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formula: 'sum(gross_deductions)',
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input: { count: grossDeductionItems.length },
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output: -totalGrossDeductions,
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})
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}
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// Gross salary = base + additions + absence (may be negative for deductions) - gross deductions
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const grossSalary = r(baseSalary + totalAdditions + totalAbsence - totalGrossDeductions)
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steps.push({
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label: 'Bruttolön',
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formula: 'base + additions + absence - gross_deductions',
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input: { base: baseSalary, additions: totalAdditions, absence: totalAbsence, gross_deductions: totalGrossDeductions },
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output: grossSalary,
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})
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// ─── Step 5: Add förmånsvärden to tax base ───
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const benefitItems = input.lineItems.filter(
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li => ['benefit_car', 'benefit_housing', 'benefit_meals', 'benefit_wellness', 'benefit_other'].includes(li.itemType)
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)
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const totalBenefits = r(benefitItems.reduce((sum, li) => sum + li.amount, 0))
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if (totalBenefits > 0) {
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steps.push({
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label: 'Förmånsvärden',
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formula: 'sum(benefit_values)',
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input: { count: benefitItems.length },
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output: totalBenefits,
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})
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}
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const taxableIncome = r(grossSalary + totalBenefits)
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steps.push({
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label: 'Skattegrundande inkomst',
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formula: 'gross_salary + benefit_values',
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input: { gross_salary: grossSalary, benefit_values: totalBenefits },
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output: taxableIncome,
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})
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// ─── Step 6: Tax withholding ───
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let taxWithheld: number
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const paymentYear = parseInt(input.paymentDate.split('-')[0])
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if (input.fSkattStatus === 'f_skatt') {
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// F-skatt holder: no withholding
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taxWithheld = 0
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steps.push({
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label: 'Skatteavdrag (F-skatt)',
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formula: '0 (F-skattsedel, inget avdrag)',
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input: {},
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output: 0,
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})
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} else if (input.fSkattStatus === 'not_verified') {
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// Unverified: flat 30%
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taxWithheld = r(taxableIncome * 0.30)
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steps.push({
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label: 'Skatteavdrag (ej verifierad)',
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formula: 'taxable_income × 30%',
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input: { taxable_income: taxableIncome },
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output: taxWithheld,
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})
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} else if (input.isSidoinkomst) {
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// Sidoinkomst: flat 30%
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taxWithheld = calculateSidoinkomstTax(taxableIncome)
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steps.push({
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label: 'Skatteavdrag (sidoinkomst 30%)',
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formula: 'taxable_income × 30%',
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input: { taxable_income: taxableIncome },
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output: taxWithheld,
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})
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} else if (input.jamkningPercentage !== null && isJamkningValid(input.jamkningValidFrom, input.jamkningValidTo, input.paymentDate)) {
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// Jämkning
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taxWithheld = calculateJamkningTax(taxableIncome, input.jamkningPercentage)
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steps.push({
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label: `Skatteavdrag (jämkning ${input.jamkningPercentage}%)`,
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formula: 'taxable_income × jamkning_percentage / 100',
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input: { taxable_income: taxableIncome, jamkning_percentage: input.jamkningPercentage },
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output: taxWithheld,
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})
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} else if (input.taxTableNumber) {
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// Normal tax table lookup
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taxWithheld = lookupTaxAmount(input.taxTableNumber, input.taxColumn, taxableIncome, taxRates)
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steps.push({
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label: `Skatteavdrag (tabell ${input.taxTableNumber}, kolumn ${input.taxColumn})`,
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formula: `lookup(table=${input.taxTableNumber}, column=${input.taxColumn}, income=${Math.round(taxableIncome)})`,
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input: { table: input.taxTableNumber, column: input.taxColumn, taxable_income: taxableIncome },
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output: taxWithheld,
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})
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} else {
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// Fallback: flat 30%
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taxWithheld = r(taxableIncome * 0.30)
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steps.push({
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label: 'Skatteavdrag (30% schablon)',
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formula: 'taxable_income × 30%',
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input: { taxable_income: taxableIncome },
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output: taxWithheld,
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})
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}
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// ─── Step 7: Net salary ───
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const netDeductionItems = input.lineItems.filter(li => li.isNetDeduction)
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const totalNetDeductions = r(Math.abs(netDeductionItems.reduce((sum, li) => sum + li.amount, 0)))
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const netSalary = r(grossSalary - taxWithheld - totalNetDeductions)
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steps.push({
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label: 'Nettolön',
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formula: 'gross - tax - net_deductions',
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input: { gross: grossSalary, tax: taxWithheld, net_deductions: totalNetDeductions },
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output: netSalary,
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})
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// ─── Step 8: Employer contributions (avgifter) ───
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const avgifterCalc = calculateAvgifterRate(input, config, paymentYear)
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const avgifterBasis = r(grossSalary + totalBenefits)
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// Handle salary caps for youth and växa-stöd:
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// Reduced rate applies only up to the cap, standard rate on the rest
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let avgifterAmount: number
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if (avgifterCalc.category === 'youth' && config.avgifterYouthSalaryCap && avgifterBasis > config.avgifterYouthSalaryCap) {
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const reducedPart = r(config.avgifterYouthSalaryCap * avgifterCalc.rate)
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const standardPart = r((avgifterBasis - config.avgifterYouthSalaryCap) * config.avgifterTotal)
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avgifterAmount = r(reducedPart + standardPart)
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steps.push(...avgifterCalc.steps)
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steps.push({
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label: 'Arbetsgivaravgifter (ungdomsrabatt med tak)',
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formula: `${config.avgifterYouthSalaryCap} × ${avgifterCalc.rate} + ${r(avgifterBasis - config.avgifterYouthSalaryCap)} × ${config.avgifterTotal}`,
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input: { cap: config.avgifterYouthSalaryCap, reduced: reducedPart, standard: standardPart },
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output: avgifterAmount,
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})
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} else if (avgifterCalc.category === 'vaxa_stod' && config.avgifterVaxaStodCap && avgifterBasis > config.avgifterVaxaStodCap) {
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const reducedPart = r(config.avgifterVaxaStodCap * avgifterCalc.rate)
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const standardPart = r((avgifterBasis - config.avgifterVaxaStodCap) * config.avgifterTotal)
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avgifterAmount = r(reducedPart + standardPart)
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steps.push(...avgifterCalc.steps)
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steps.push({
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label: 'Arbetsgivaravgifter (växa-stöd med tak)',
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formula: `${config.avgifterVaxaStodCap} × ${avgifterCalc.rate} + ${r(avgifterBasis - config.avgifterVaxaStodCap)} × ${config.avgifterTotal}`,
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input: { cap: config.avgifterVaxaStodCap, reduced: reducedPart, standard: standardPart },
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output: avgifterAmount,
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})
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} else {
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avgifterAmount = r(avgifterBasis * avgifterCalc.rate)
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steps.push(...avgifterCalc.steps)
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steps.push({
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label: 'Arbetsgivaravgifter',
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formula: 'avgifter_basis × rate',
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input: { avgifter_basis: avgifterBasis, rate: avgifterCalc.rate },
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output: avgifterAmount,
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})
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}
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// ─── Step 9: Vacation accrual ───
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const vacationBasisItems = input.lineItems.filter(li => li.isVacationBasis)
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const vacationBasis = r(
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baseSalary + vacationBasisItems.reduce((sum, li) => sum + li.amount, 0)
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)
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let vacationAccrual: number
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if (input.vacationRule === 'procentregeln') {
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const rate = input.vacationDaysPerYear >= 30 ? 0.144 : 0.12
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vacationAccrual = r(vacationBasis * rate)
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steps.push({
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label: `Semesteravsättning (procentregeln ${rate * 100}%)`,
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formula: 'vacation_basis × rate',
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input: { vacation_basis: vacationBasis, rate },
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output: vacationAccrual,
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})
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} else {
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// Sammalöneregeln (§16a): employee keeps regular salary during vacation
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// + semestertillägg per day (min 0.43%, often 0.8% per CBA)
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// Accrual = tillägg only (salary cost is already in normal monthly expense)
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// The liability (2920) for sammalöneregeln is the tillägg portion,
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// since the base salary is expensed monthly regardless of vacation.
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const dailyRate = r(input.monthlySalary / 21)
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const tillagg = r(dailyRate * input.semestertillaggRate * input.vacationDaysPerYear)
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vacationAccrual = tillagg
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steps.push({
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label: `Semesteravsättning (sammalöneregeln, tillägg ${(input.semestertillaggRate * 100).toFixed(2)}%)`,
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formula: 'daily_rate × semestertillagg_rate × vacation_days',
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input: { daily_rate: dailyRate, semestertillagg_rate: input.semestertillaggRate, vacation_days: input.vacationDaysPerYear },
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output: vacationAccrual,
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})
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}
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// ─── Step 10: Avgifter on vacation accrual ───
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const vacationAccrualAvgifter = r(vacationAccrual * avgifterCalc.rate)
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steps.push({
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label: 'Arbetsgivaravgifter på semesteravsättning',
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formula: 'vacation_accrual × avgifter_rate',
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input: { vacation_accrual: vacationAccrual, avgifter_rate: avgifterCalc.rate },
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output: vacationAccrualAvgifter,
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})
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const totalEmployerCost = r(grossSalary + avgifterAmount + vacationAccrual + vacationAccrualAvgifter)
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steps.push({
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label: 'Total arbetsgivarkostnad',
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formula: 'gross + avgifter + vacation_accrual + vacation_avgifter',
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input: { gross: grossSalary, avgifter: avgifterAmount, vacation_accrual: vacationAccrual, vacation_avgifter: vacationAccrualAvgifter },
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output: totalEmployerCost,
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})
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return {
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grossSalary,
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grossDeductions: totalGrossDeductions,
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benefitValues: totalBenefits,
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taxableIncome,
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taxWithheld,
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netDeductions: totalNetDeductions,
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netSalary,
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avgifterRate: avgifterCalc.rate,
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avgifterAmount,
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avgifterBasis,
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avgifterCategory: avgifterCalc.category,
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vacationAccrual,
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vacationAccrualAvgifter,
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totalEmployerCost,
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steps,
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}
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}
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// ============================================================
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// Avgifter calculation
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// ============================================================
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/**
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* Determine arbetsgivaravgifter rate based on employee age, växa-stöd, etc.
|
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*/
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export function calculateAvgifterRate(
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input: SalaryCalculationInput,
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config: PayrollConfig,
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paymentYear: number
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): AvgifterCalculation {
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const steps: CalculationStep[] = []
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||||
|
||||
// Decrypt personnummer to calculate age
|
||||
let pnr: string
|
||||
try {
|
||||
pnr = decryptPersonnummer(input.personnummer)
|
||||
} catch {
|
||||
// If decryption fails, assume standard rate
|
||||
return {
|
||||
rate: config.avgifterTotal,
|
||||
amount: 0,
|
||||
basis: 0,
|
||||
category: 'standard',
|
||||
steps: [{ label: 'Avgiftskategori', formula: 'standard (personnummer ej dekrypterbart)', input: {}, output: config.avgifterTotal }],
|
||||
}
|
||||
}
|
||||
|
||||
const ageAtYearStart = calculateAgeAtYearStart(pnr, paymentYear)
|
||||
|
||||
// Born ≤1937: 0%
|
||||
const birthYear = parseInt(pnr.slice(0, 4))
|
||||
if (birthYear <= 1937) {
|
||||
steps.push({
|
||||
label: 'Avgiftskategori',
|
||||
formula: 'Född ≤1937: 0%',
|
||||
input: { birth_year: birthYear },
|
||||
output: 0,
|
||||
})
|
||||
return { rate: 0, amount: 0, basis: 0, category: 'exempt', steps }
|
||||
}
|
||||
|
||||
// 67+ at year start (reduced — only ålderspension)
|
||||
if (ageAtYearStart >= config.reducedAvgiftAge) {
|
||||
steps.push({
|
||||
label: 'Avgiftskategori',
|
||||
formula: `Ålder ${ageAtYearStart} ≥ ${config.reducedAvgiftAge}: reducerad (${config.avgifterReduced65plus * 100}%)`,
|
||||
input: { age: ageAtYearStart, threshold: config.reducedAvgiftAge },
|
||||
output: config.avgifterReduced65plus,
|
||||
})
|
||||
return { rate: config.avgifterReduced65plus, amount: 0, basis: 0, category: 'reduced_65plus', steps }
|
||||
}
|
||||
|
||||
// Växa-stöd eligible
|
||||
if (input.vaxaStodEligible && input.vaxaStodStart && input.vaxaStodEnd) {
|
||||
const payDate = input.paymentDate
|
||||
if (payDate >= input.vaxaStodStart && payDate <= input.vaxaStodEnd && config.avgifterVaxaStodRate !== null) {
|
||||
steps.push({
|
||||
label: 'Avgiftskategori',
|
||||
formula: `Växa-stöd: ${(config.avgifterVaxaStodRate ?? 0) * 100}% på första ${config.avgifterVaxaStodCap} SEK`,
|
||||
input: { vaxa_cap: config.avgifterVaxaStodCap ?? 0 },
|
||||
output: config.avgifterVaxaStodRate ?? 0,
|
||||
})
|
||||
return { rate: config.avgifterVaxaStodRate ?? config.avgifterTotal, amount: 0, basis: 0, category: 'vaxa_stod', steps }
|
||||
}
|
||||
}
|
||||
|
||||
// Youth rate (2026: ages 19-23, Apr-Sep only)
|
||||
if (config.avgifterYouthRate !== null && ageAtYearStart >= 19 && ageAtYearStart <= 23) {
|
||||
const [, monthStr] = input.paymentDate.split('-')
|
||||
const month = parseInt(monthStr)
|
||||
// Youth rate valid Apr 2026 - Sep 2027
|
||||
const isYouthPeriod = (paymentYear === 2026 && month >= 4) || (paymentYear === 2027 && month <= 9)
|
||||
if (isYouthPeriod) {
|
||||
steps.push({
|
||||
label: 'Avgiftskategori',
|
||||
formula: `Ungdomsrabatt (${ageAtYearStart} år): ${config.avgifterYouthRate * 100}% på första ${config.avgifterYouthSalaryCap} SEK`,
|
||||
input: { age: ageAtYearStart, cap: config.avgifterYouthSalaryCap ?? 0 },
|
||||
output: config.avgifterYouthRate,
|
||||
})
|
||||
return { rate: config.avgifterYouthRate, amount: 0, basis: 0, category: 'youth', steps }
|
||||
}
|
||||
}
|
||||
|
||||
// Standard rate
|
||||
steps.push({
|
||||
label: 'Avgiftskategori',
|
||||
formula: `Standard: ${config.avgifterTotal * 100}%`,
|
||||
input: { age: ageAtYearStart },
|
||||
output: config.avgifterTotal,
|
||||
})
|
||||
return { rate: config.avgifterTotal, amount: 0, basis: 0, category: 'standard', steps }
|
||||
}
|
||||
|
||||
// ============================================================
|
||||
// Sjuklön helpers
|
||||
// ============================================================
|
||||
|
||||
/**
|
||||
* Calculate karensavdrag (sick leave deduction day 1).
|
||||
* Formula: 20% × (monthly_salary × 12 / 52 × sjuklön_rate)
|
||||
*/
|
||||
export function calculateKarensavdrag(monthlySalary: number, config: PayrollConfig): number {
|
||||
const weeklySjuklon = r(monthlySalary * 12 / 52 * config.sjuklonRate)
|
||||
return r(weeklySjuklon * config.karensavdragFactor)
|
||||
}
|
||||
|
||||
/**
|
||||
* Calculate sjuklön for days 2-14.
|
||||
* Formula: 80% × daily_rate × (sick_days - 1)
|
||||
*/
|
||||
export function calculateSjuklon(
|
||||
monthlySalary: number,
|
||||
sickDays: number,
|
||||
config: PayrollConfig
|
||||
): { karensavdrag: number; sjuklon: number; totalDeduction: number; steps: CalculationStep[] } {
|
||||
const steps: CalculationStep[] = []
|
||||
const dailyRate = r(monthlySalary / 21)
|
||||
|
||||
// Karensavdrag
|
||||
const karensavdrag = calculateKarensavdrag(monthlySalary, config)
|
||||
steps.push({
|
||||
label: 'Karensavdrag',
|
||||
formula: '20% × (monthly × 12/52 × 80%)',
|
||||
input: { monthly_salary: monthlySalary },
|
||||
output: karensavdrag,
|
||||
})
|
||||
|
||||
// Sjuklön day 2-14
|
||||
const sjuklonDays = Math.min(Math.max(sickDays - 1, 0), 13)
|
||||
const sjuklon = r(dailyRate * config.sjuklonRate * sjuklonDays)
|
||||
steps.push({
|
||||
label: 'Sjuklön dag 2-14',
|
||||
formula: 'daily_rate × 80% × (sick_days - 1)',
|
||||
input: { daily_rate: dailyRate, sjuklon_rate: config.sjuklonRate, days: sjuklonDays },
|
||||
output: sjuklon,
|
||||
})
|
||||
|
||||
// Total deduction from pay = salary they would have earned - sjuklön they get
|
||||
const fullPayForPeriod = r(dailyRate * sickDays)
|
||||
const totalDeduction = r(-(fullPayForPeriod - sjuklon + karensavdrag))
|
||||
steps.push({
|
||||
label: 'Netto sjukavdrag',
|
||||
formula: '-(full_pay - sjuklon + karensavdrag)',
|
||||
input: { full_pay: fullPayForPeriod, sjuklon, karensavdrag },
|
||||
output: totalDeduction,
|
||||
})
|
||||
|
||||
return { karensavdrag, sjuklon, totalDeduction, steps }
|
||||
}
|
||||
|
||||
/**
|
||||
* Calculate vacation accrual.
|
||||
*/
|
||||
export function calculateVacationAccrual(params: {
|
||||
monthlySalary: number
|
||||
vacationRule: 'procentregeln' | 'sammaloneregeln'
|
||||
vacationDaysPerYear: number
|
||||
semestertillaggRate: number
|
||||
vacationBasis: number
|
||||
}): { accrual: number; steps: CalculationStep[] } {
|
||||
const steps: CalculationStep[] = []
|
||||
|
||||
if (params.vacationRule === 'procentregeln') {
|
||||
const rate = params.vacationDaysPerYear >= 30 ? 0.144 : 0.12
|
||||
const accrual = r(params.vacationBasis * rate)
|
||||
steps.push({
|
||||
label: `Semesteravsättning (procentregeln ${rate * 100}%)`,
|
||||
formula: 'vacation_basis × rate',
|
||||
input: { vacation_basis: params.vacationBasis, rate },
|
||||
output: accrual,
|
||||
})
|
||||
return { accrual, steps }
|
||||
} else {
|
||||
const dailyRate = r(params.monthlySalary / 21)
|
||||
const accrual = r(dailyRate * params.semestertillaggRate * params.vacationDaysPerYear)
|
||||
steps.push({
|
||||
label: `Semesteravsättning (sammalöneregeln ${params.semestertillaggRate * 100}%)`,
|
||||
formula: 'daily_rate × semestertillagg_rate × vacation_days',
|
||||
input: { daily_rate: dailyRate, rate: params.semestertillaggRate, days: params.vacationDaysPerYear },
|
||||
output: accrual,
|
||||
})
|
||||
return { accrual, steps }
|
||||
}
|
||||
}
|
||||
|
||||
// ============================================================
|
||||
// Helpers
|
||||
// ============================================================
|
||||
|
||||
function isJamkningValid(
|
||||
validFrom: string | null,
|
||||
validTo: string | null,
|
||||
paymentDate: string
|
||||
): boolean {
|
||||
if (!validFrom || !validTo) return false
|
||||
return paymentDate >= validFrom && paymentDate <= validTo
|
||||
}
|
||||
Reference in New Issue
Block a user