import { NextResponse } from 'next/server'
import { ensureInitialized } from '@/lib/init'
import { withRouteContext } from '@/lib/api/with-route-context'
import { validateBody } from '@/lib/api/validate'
import { CreateEmployeeSchema } from '@/lib/api/schemas'
import { getCompanyEntityType } from '@/lib/company/context'
import { encryptPersonnummer, extractLast4, maskEmployeeForResponse, maskPersonnummer, validatePersonnummer } from '@/lib/salary/personnummer'
import { isEmploymentTypeAllowedForEntity, EF_OWNER_EMPLOYMENT_ERROR } from '@/lib/salary/employment-rules'
import { getErrorMessage as getUserErrorMessage } from '@/lib/errors/get-error-message'

ensureInitialized()

export const GET = withRouteContext('salary.employees.list', async (request, { supabase, companyId }) => {
  const { searchParams } = new URL(request.url)
  const activeOnly = searchParams.get('active') !== 'false'

  let query = supabase
    .from('employees')
    .select('*')
    .eq('company_id', companyId)

  if (activeOnly) {
    query = query.eq('is_active', true)
  }

  const { data, error } = await query.order('last_name')

  if (error) {
    return NextResponse.json({ error: getUserErrorMessage(error) }, { status: 500 })
  }

  // Mask personnummer: show birthdate, hide the 4-digit suffix. The shared
  // helper also strips personnummer_last4: mask + last4 in the same payload
  // would reassemble the full personnummer.
  const masked = (data || []).map((emp) => maskEmployeeForResponse(emp))

  return NextResponse.json({ data: masked })
})

export const POST = withRouteContext('salary.employees.create', async (request, { supabase, companyId, user }) => {
  const validation = await validateBody(request, CreateEmployeeSchema)
  if (!validation.success) return validation.response
  const body = validation.data

  // Validate personnummer format + Luhn
  const pnrValidation = validatePersonnummer(body.personnummer)
  if (!pnrValidation.valid) {
    return NextResponse.json({ error: pnrValidation.error }, { status: 400 })
  }

  // An enskild firma owner cannot be put on payroll (they take egna uttag, not
  // lön). Block owner/board employment types for EF before inserting. The DB
  // trigger enforce_ef_no_owner_employee is the all-paths backstop; this gives
  // a clean 400 with guidance. #782
  const entityType = await getCompanyEntityType(supabase, companyId)
  if (!isEmploymentTypeAllowedForEntity(entityType, body.employment_type)) {
    return NextResponse.json({ error: EF_OWNER_EMPLOYMENT_ERROR }, { status: 400 })
  }

  // Encrypt personnummer
  const encryptedPnr = encryptPersonnummer(body.personnummer)
  const last4 = extractLast4(body.personnummer)

  const { data: employee, error } = await supabase
    .from('employees')
    .insert({
      company_id: companyId,
      user_id: user.id,
      first_name: body.first_name,
      last_name: body.last_name,
      personnummer: encryptedPnr,
      personnummer_last4: last4,
      employment_type: body.employment_type,
      employment_start: body.employment_start,
      employment_end: body.employment_end || null,
      employment_degree: body.employment_degree,
      hours_per_week: body.hours_per_week,
      workdays_per_week: body.workdays_per_week,
      salary_type: body.salary_type,
      monthly_salary: body.monthly_salary || null,
      hourly_rate: body.hourly_rate || null,
      tax_table_number: body.tax_table_number || null,
      tax_column: body.tax_column,
      tax_municipality: body.tax_municipality || null,
      is_sidoinkomst: body.is_sidoinkomst,
      f_skatt_status: body.f_skatt_status,
      clearing_number: body.clearing_number || null,
      bank_account_number: body.bank_account_number || null,
      vacation_rule: body.vacation_rule,
      vacation_days_per_year: body.vacation_days_per_year,
      semestertillagg_rate: body.semestertillagg_rate,
      email: body.email || null,
      phone: body.phone || null,
      address_line1: body.address_line1 || null,
      postal_code: body.postal_code || null,
      city: body.city || null,
      vaxa_stod_eligible: body.vaxa_stod_eligible,
      vaxa_stod_start: body.vaxa_stod_start || null,
      vaxa_stod_end: body.vaxa_stod_end || null,
      jamkning_percentage: body.jamkning_percentage ?? null,
      jamkning_valid_from: body.jamkning_valid_from ?? null,
      jamkning_valid_to: body.jamkning_valid_to ?? null,
      // Dimensions PR8: bag for the employee's P&L cost lines at booking.
      default_dimensions: body.default_dimensions ?? {},
    })
    .select()
    .single()

  if (error) {
    if (error.code === '23505') {
      return NextResponse.json({ error: 'En anställd med detta personnummer finns redan' }, { status: 409 })
    }
    return NextResponse.json({ error: getUserErrorMessage(error) }, { status: 500 })
  }

  // Same rule as the read surfaces: the create response carries the mask under
  // `personnummer_masked` only. Spreading the inserted row would otherwise echo
  // the stored ciphertext under `personnummer`, and personnummer_last4 must not
  // ride along with the mask (mask + last4 = the full personnummer).
  const { personnummer: _storedPnr, personnummer_last4: _storedLast4, ...created } = employee
  return NextResponse.json({
    data: {
      ...created,
      personnummer_masked: maskPersonnummer(body.personnummer),
    },
  }, { status: 201 })
}, { requireWrite: true })