import { z } from 'zod'

// ============================================================
// Shared primitives
// ============================================================

/** UUID v4 string */
const uuid = z.string().uuid()

/** ISO date string (YYYY-MM-DD) */
const isoDate = z.string().regex(/^\d{4}-\d{2}-\d{2}$/, 'Expected YYYY-MM-DD date format')

/** BAS account number — always a string of 4 digits */
const accountNumber = z.string().regex(/^\d{4}$/, 'Account number must be exactly 4 digits')

/** Non-negative monetary amount (>= 0) */
const nonNegativeAmount = z.number().nonnegative()

/** Time string (HH:MM or HH:MM:SS) */
const timeString = z.string().regex(/^\d{2}:\d{2}(:\d{2})?$/, 'Expected HH:MM or HH:MM:SS time format')

// ============================================================
// Enum schemas (matching types/index.ts)
// ============================================================

export const EntityTypeSchema = z.enum(['enskild_firma', 'aktiebolag'])

export const CustomerTypeSchema = z.enum([
  'individual',
  'swedish_business',
  'eu_business',
  'non_eu_business',
])

export const SupplierTypeSchema = z.enum([
  'swedish_business',
  'eu_business',
  'non_eu_business',
])

export const InvoiceStatusSchema = z.enum([
  'draft', 'sent', 'paid', 'overdue', 'cancelled', 'credited',
])

export const InvoiceDocumentTypeSchema = z.enum([
  'invoice', 'proforma', 'delivery_note',
])

export const SupplierInvoiceStatusSchema = z.enum([
  'registered', 'approved', 'paid', 'partially_paid', 'overdue', 'disputed', 'credited',
])

export const VatTreatmentSchema = z.enum([
  'standard_25', 'reduced_12', 'reduced_6', 'reverse_charge', 'export', 'exempt',
])

export const AccountingMethodSchema = z.enum(['accrual', 'cash'])

export const CurrencySchema = z.enum(['SEK', 'EUR', 'USD', 'GBP', 'NOK', 'DKK'])

export const TransactionCategorySchema = z.enum([
  'income_services',
  'income_products',
  'income_other',
  'expense_equipment',
  'expense_software',
  'expense_travel',
  'expense_office',
  'expense_marketing',
  'expense_professional_services',
  'expense_education',
  'expense_representation',
  'expense_consumables',
  'expense_vehicle',
  'expense_telecom',
  'expense_bank_fees',
  'expense_card_fees',
  'expense_currency_exchange',
  'expense_other',
  'private',
  'uncategorized',
])

export const JournalEntrySourceTypeSchema = z.enum([
  'manual',
  'bank_transaction',
  'invoice_created',
  'invoice_paid',
  'invoice_cash_payment',
  'credit_note',
  'salary_payment',
  'opening_balance',
  'year_end',
  'storno',
  'correction',
  'import',
  'system',
  'supplier_invoice_registered',
  'supplier_invoice_paid',
  'supplier_invoice_cash_payment',
  'supplier_credit_note',
  'currency_revaluation',
])

export const AccountTypeSchema = z.enum([
  'asset', 'equity', 'liability', 'revenue', 'expense',
])

export const NormalBalanceSchema = z.enum(['debit', 'credit'])

export const MappingRuleTypeSchema = z.enum([
  'mcc_code', 'merchant_name', 'description_pattern', 'amount_threshold', 'combined',
])

export const RiskLevelSchema = z.enum(['NONE', 'LOW', 'MEDIUM', 'HIGH', 'VERY_HIGH'])

export const DeadlineTypeSchema = z.enum([
  'delivery', 'invoicing', 'report', 'tax', 'other',
])

export const DeadlinePrioritySchema = z.enum(['critical', 'important', 'normal'])

export const TaxDeadlineTypeSchema = z.enum([
  'moms_monthly',
  'moms_quarterly',
  'moms_yearly',
  'f_skatt',
  'arbetsgivardeklaration',
  'inkomstdeklaration_ef',
  'inkomstdeklaration_ab',
  'arsredovisning',
  'periodisk_sammanstallning',
  'bokslut',
])

export const DeadlineSourceSchema = z.enum(['system', 'user'])

export const MomsPeriodSchema = z.enum(['monthly', 'quarterly', 'yearly'])

export const DocumentUploadSourceSchema = z.enum([
  'camera', 'file_upload', 'email', 'e_invoice', 'scan', 'api', 'system',
])

// ============================================================
// Invoice schemas
// ============================================================

export const CreateInvoiceItemSchema = z.object({
  description: z.string().min(1, 'Item description is required'),
  quantity: z.number().positive('Quantity must be positive'),
  unit: z.string().min(1, 'Unit is required'),
  unit_price: z.number(),
  vat_rate: z.number().min(0).max(100).optional(),
})

const optionalIsoDate = isoDate.or(z.literal('')).transform(v => v || undefined).optional()

export const CreateInvoiceSchema = z.object({
  customer_id: uuid,
  invoice_date: isoDate,
  due_date: isoDate,
  delivery_date: optionalIsoDate,
  currency: CurrencySchema,
  document_type: InvoiceDocumentTypeSchema.optional(),
  your_reference: z.string().optional(),
  our_reference: z.string().optional(),
  notes: z.string().optional(),
  items: z.array(CreateInvoiceItemSchema).min(1, 'At least one item is required'),
})

export const CreateCreditNoteSchema = z.object({
  credited_invoice_id: uuid,
  reason: z.string().optional(),
})

export const MarkInvoicePaidSchema = z.object({
  payment_date: isoDate.optional(),
  exchange_rate_difference: z.number().optional(),
  notes: z.string().optional(),
  lines: z.array(z.object({
    account_number: accountNumber,
    debit_amount: nonNegativeAmount.default(0),
    credit_amount: nonNegativeAmount.default(0),
    line_description: z.string().optional(),
  })).min(2).optional(),
})

// ============================================================
// Customer schemas
// ============================================================

export const CreateCustomerSchema = z.object({
  name: z.string().min(1, 'Customer name is required'),
  customer_type: CustomerTypeSchema,
  email: z.string().email('Invalid email address').optional(),
  phone: z.string().optional(),
  address_line1: z.string().optional(),
  address_line2: z.string().optional(),
  postal_code: z.string().optional(),
  city: z.string().optional(),
  country: z.string().optional(),
  org_number: z.string().optional(),
  vat_number: z.string().optional(),
  default_payment_terms: z.number().int().positive().optional(),
  notes: z.string().optional(),
})

export const UpdateCustomerSchema = CreateCustomerSchema.partial()

// ============================================================
// Supplier schemas
// ============================================================

export const CreateSupplierSchema = z.object({
  name: z.string().min(1, 'Supplier name is required'),
  supplier_type: SupplierTypeSchema,
  email: z.string().email('Invalid email address').optional(),
  phone: z.string().optional(),
  address_line1: z.string().optional(),
  address_line2: z.string().optional(),
  postal_code: z.string().optional(),
  city: z.string().optional(),
  country: z.string().optional(),
  org_number: z.string().optional(),
  vat_number: z.string().optional(),
  bankgiro: z.string().optional(),
  plusgiro: z.string().optional(),
  bank_account: z.string().optional(),
  iban: z.string().optional(),
  bic: z.string().optional(),
  default_expense_account: accountNumber.optional(),
  default_payment_terms: z.number().int().positive().optional(),
  default_currency: CurrencySchema.nullable().optional(),
  notes: z.string().optional(),
})

export const UpdateSupplierSchema = CreateSupplierSchema.partial()

// ============================================================
// Supplier invoice schemas
// ============================================================

export const CreateSupplierInvoiceItemSchema = z.object({
  description: z.string().min(1, 'Item description is required'),
  amount: z.number().optional(),
  account_number: accountNumber,
  vat_rate: z.number().min(0).max(100).optional(),
  vat_code: z.string().optional(),
  quantity: z.number().optional(),
  unit: z.string().optional(),
  unit_price: z.number().optional(),
})

export const CreateSupplierInvoiceSchema = z.object({
  supplier_id: uuid,
  supplier_invoice_number: z.string().min(1, 'Supplier invoice number is required'),
  invoice_date: isoDate,
  due_date: isoDate,
  delivery_date: optionalIsoDate,
  currency: CurrencySchema.optional(),
  exchange_rate: z.number().positive().optional(),
  vat_treatment: VatTreatmentSchema.optional(),
  reverse_charge: z.boolean().optional(),
  payment_reference: z.string().optional(),
  notes: z.string().optional(),
  items: z.array(CreateSupplierInvoiceItemSchema).min(1, 'At least one item is required'),
})

export const MarkSupplierInvoicePaidSchema = z.object({
  amount: z.number().positive().optional(),
  payment_date: isoDate.optional(),
  exchange_rate_difference: z.number().optional(),
  notes: z.string().optional(),
})

export const UpdateSupplierInvoiceSchema = z.object({
  supplier_invoice_number: z.string().min(1).optional(),
  invoice_date: isoDate.optional(),
  due_date: isoDate.optional(),
  delivery_date: optionalIsoDate,
  payment_reference: z.string().optional(),
  notes: z.string().optional(),
})

// ============================================================
// Journal entry schemas
// ============================================================

export const CreateJournalEntryLineSchema = z.object({
  account_number: accountNumber,
  debit_amount: nonNegativeAmount.default(0),
  credit_amount: nonNegativeAmount.default(0),
  line_description: z.string().optional(),
  currency: z.string().optional(),
  amount_in_currency: z.number().optional(),
  exchange_rate: z.number().positive().optional(),
  tax_code: z.string().optional(),
  cost_center: z.string().optional(),
  project: z.string().optional(),
})

export const CreateJournalEntrySchema = z.object({
  fiscal_period_id: uuid,
  entry_date: isoDate,
  description: z.string().min(1, 'Description is required'),
  source_type: JournalEntrySourceTypeSchema.default('manual'),
  source_id: z.string().optional(),
  voucher_series: z.string().regex(/^[A-Z]$/, 'Verifikationsserie måste vara en bokstav A–Z').optional(),
  notes: z.string().max(2000).optional(),
  lines: z.array(CreateJournalEntryLineSchema).min(2, 'At least two lines are required for double-entry'),
})

export const CorrectJournalEntrySchema = z.object({
  lines: z.array(CreateJournalEntryLineSchema).min(2, 'At least two lines are required for double-entry'),
})

// ============================================================
// Transaction schemas
// ============================================================

export const CategorizeTransactionSchema = z.object({
  is_business: z.boolean(),
  category: TransactionCategorySchema.optional(),
  template_id: z.string().optional(),
  vat_treatment: VatTreatmentSchema.optional(),
  account_override: accountNumber.optional(),
  counterparty_template_id: z.string().uuid().optional(),
  user_description: z.string().max(500).optional(),
  inbox_item_id: z.string().uuid().optional(),
})

export const BookTransactionSchema = z.object({
  fiscal_period_id: uuid,
  entry_date: isoDate,
  description: z.string().min(1, 'Description is required'),
  lines: z.array(CreateJournalEntryLineSchema).min(1, 'At least one line is required'),
})

export const MatchInvoiceSchema = z.object({
  invoice_id: uuid,
})

export const MatchSupplierInvoiceSchema = z.object({
  supplier_invoice_id: uuid,
})


// ============================================================
// Settings schemas
// ============================================================

export const UpdateSettingsSchema = z.object({
  entity_type: EntityTypeSchema.optional(),
  company_name: z.string().optional(),
  trade_name: z.string().nullable().optional(),
  org_number: z.string().optional(),
  address_line1: z.string().optional(),
  address_line2: z.string().optional(),
  postal_code: z.string().optional(),
  city: z.string().optional(),
  country: z.string().optional(),
  f_skatt: z.boolean().optional(),
  vat_registered: z.boolean().optional(),
  vat_number: z.string().regex(/^SE\d{12}$/, 'Momsregistreringsnummer måste vara SE följt av 12 siffror').nullable().optional(),
  moms_period: MomsPeriodSchema.nullable().optional(),
  fiscal_year_start_month: z.number().int().min(1).max(12).optional(),
  preliminary_tax_monthly: z.number().nullable().optional(),
  bank_name: z.string().max(100, 'Banknamn får vara max 100 tecken').optional(),
  clearing_number: z.string().regex(/^\d{4,5}$/, 'Clearingnummer måste vara 4-5 siffror').optional().or(z.literal('')),
  account_number: z.string().regex(/^\d{6,12}$/, 'Kontonummer måste vara 6-12 siffror').optional().or(z.literal('')),
  bankgiro: z.string().regex(/^(\d{3,4}-\d{4}|\d{7,8})$/, 'Ogiltigt bankgironummer (7-8 siffror)').nullable().optional().or(z.literal('')),
  plusgiro: z.string().regex(/^\d{1,7}-\d{1}$/, 'Ogiltigt plusgironummer').nullable().optional().or(z.literal('')),
  iban: z.string().optional(),
  bic: z.string().optional(),
  accounting_method: AccountingMethodSchema.optional(),
  invoice_prefix: z.string().nullable().optional(),
  next_invoice_number: z.number().int().positive().optional(),
  invoice_default_days: z.number().int().positive().optional(),
  invoice_default_notes: z.string().nullable().optional(),
  phone: z.string().optional(),
  email: z.string().email().optional().or(z.literal('')),
  website: z.string().optional().or(z.literal('')),
  pays_salaries: z.boolean().optional(),
  sector_slug: z.string().nullable().optional(),
  // Bookkeeping lock
  bookkeeping_locked_through: z.string().regex(/^\d{4}-\d{2}-\d{2}$/, 'Ogiltigt datumformat (YYYY-MM-DD)').nullable().optional(),
  auto_lock_period_days: z.number().int().positive().nullable().optional(),
  // Voucher series
  default_voucher_series: z.string().regex(/^[A-Z]$/, 'Verifikationsserie måste vara en bokstav A–Z').optional(),
  // Invoice PDF settings
  ore_rounding: z.boolean().optional(),
  invoice_show_ocr: z.boolean().optional(),
  invoice_show_bankgiro: z.boolean().optional(),
  invoice_show_plusgiro: z.boolean().optional(),
  invoice_late_fee_text: z.string().nullable().optional(),
  invoice_credit_terms_text: z.string().nullable().optional(),
  // AI agent flow
  ai_flow_enabled: z.boolean().optional(),
  // Agent auto-commit (low-risk ops staged by trusted agents)
  agent_auto_commit_enabled: z.boolean().optional(),
  agent_auto_commit_max_amount: z.number().nullable().optional(),
}).refine(
  (data) => {
    // BFL 3 kap.: Enskild firma must have fiscal year starting January
    if (data.entity_type === 'enskild_firma' && data.fiscal_year_start_month !== undefined) {
      return data.fiscal_year_start_month === 1
    }
    return true
  },
  {
    message: 'Enskild firma must have fiscal year starting in January (BFL 3 kap.)',
    path: ['fiscal_year_start_month'],
  }
).refine(
  (data) => {
    // BFNAR 2006:1: Aktiebolag must use accrual accounting (faktureringsmetoden)
    if (data.entity_type === 'aktiebolag' && data.accounting_method !== undefined) {
      return data.accounting_method === 'accrual'
    }
    return true
  },
  {
    message: 'Aktiebolag måste använda faktureringsmetoden (BFNAR 2006:1)',
    path: ['accounting_method'],
  }
)

// ============================================================
// Fiscal period schemas
// ============================================================

export const CreateFiscalPeriodSchema = z.object({
  name: z.string().min(1, 'Period name is required'),
  period_start: isoDate,
  period_end: isoDate,
}).refine(
  (data) => data.period_start < data.period_end,
  {
    message: 'Period start must be before period end',
    path: ['period_end'],
  }
)

// ============================================================
// Mapping rule schemas
// ============================================================

export const CreateMappingRuleSchema = z.object({
  rule_name: z.string().min(1, 'Rule name is required'),
  rule_type: MappingRuleTypeSchema,
  priority: z.number().int().min(0).optional(),
  mcc_codes: z.array(z.string()).optional(),
  merchant_pattern: z.string().optional(),
  description_pattern: z.string().optional(),
  amount_min: z.number().optional(),
  amount_max: z.number().optional(),
  debit_account: accountNumber,
  credit_account: accountNumber,
  vat_treatment: z.string().optional(),
  risk_level: RiskLevelSchema.optional(),
  default_private: z.boolean().optional(),
  requires_review: z.boolean().optional(),
  confidence_score: z.number().min(0).max(1).optional(),
})

export const EvaluateMappingRulesSchema = z.union([
  z.object({ transaction_id: uuid }),
  z.object({
    description: z.string().optional(),
    amount: z.number(),
  }).passthrough(),
])

// ============================================================
// Deadline schemas
// ============================================================

export const CreateDeadlineSchema = z.object({
  title: z.string().min(1, 'Title is required'),
  due_date: isoDate,
  due_time: timeString.nullish(),
  deadline_type: DeadlineTypeSchema,
  priority: DeadlinePrioritySchema.nullish(),
  customer_id: uuid.nullish(),
  notes: z.string().nullish(),
  tax_deadline_type: TaxDeadlineTypeSchema.nullish(),
  tax_period: z.string().nullish(),
  source: DeadlineSourceSchema.optional(),
  linked_report_type: z.string().nullish(),
  linked_report_period: z.record(z.string(), z.unknown()).nullish(),
})

// ============================================================
// Account schemas
// ============================================================

export const CreateAccountSchema = z.object({
  account_number: accountNumber,
  account_name: z.string().min(1, 'Account name is required'),
  account_type: AccountTypeSchema,
  normal_balance: NormalBalanceSchema,
  plan_type: z.enum(['k1', 'full_bas']).optional(),
  description: z.string().nullable().optional(),
  default_vat_code: z.string().nullable().optional(),
  sru_code: z.string().nullable().optional(),
})

export const UpdateAccountSchema = z.object({
  account_name: z.string().min(1).optional(),
  is_active: z.boolean().optional(),
  description: z.string().nullable().optional(),
  default_vat_code: z.string().nullable().optional(),
  sru_code: z.string().nullable().optional(),
})

// ============================================================
// Bank reconciliation schemas
// ============================================================

export const BankLinkSchema = z.object({
  transaction_id: uuid,
  journal_entry_id: uuid,
})

export const BankUnlinkSchema = z.object({
  transaction_id: uuid,
})

export const RunReconciliationSchema = z.object({
  date_from: isoDate.optional(),
  date_to: isoDate.optional(),
  dry_run: z.boolean().optional(),
})

// ============================================================
// Report query schemas
// ============================================================

export const VatDeclarationQuerySchema = z.object({
  periodType: z.enum(['monthly', 'quarterly', 'yearly']),
  year: z.coerce.number().int().min(2000).max(2100),
  period: z.coerce.number().int().min(1).max(12),
})

export const ReportPeriodQuerySchema = z.object({
  fiscal_period_id: uuid.optional(),
  year: z.coerce.number().int().min(2000).max(2100).optional(),
  month: z.coerce.number().int().min(1).max(12).optional(),
})

// ============================================================
// VAT validation schemas
// ============================================================

export const ValidateVatNumberSchema = z.object({
  vat_number: z.string().min(4, 'VAT number must be at least 4 characters'),
  customer_id: uuid.optional(),
})

// ============================================================
// Pagination schemas
// ============================================================

export const PaginationQuerySchema = z.object({
  limit: z.coerce.number().int().min(1).max(100).default(50),
  offset: z.coerce.number().int().nonnegative().default(0),
})

// ============================================================
// Event log schemas
// ============================================================

export const EventsQuerySchema = z.object({
  after: z.coerce.number().int().nonnegative().optional(),
  types: z.string()
    .transform(s => s.split(',').map(t => t.trim()).filter(Boolean))
    .optional(),
  limit: z.coerce.number().int().min(1).max(100).default(50),
})

// ============================================================
// Pending operations schemas
// ============================================================

export const PendingOperationsQuerySchema = z.object({
  status: z.enum(['pending', 'committed', 'rejected']).default('pending'),
  limit: z.coerce.number().int().min(1).max(100).default(50),
  offset: z.coerce.number().int().nonnegative().default(0),
})

// ============================================================
// Voucher gap schemas
// ============================================================

export const VoucherGapQuerySchema = z.object({
  fiscal_period_id: uuid,
  voucher_series: z.string().regex(/^[A-Z]$/, 'Verifikationsserie måste vara en bokstav A–Z').optional(),
})

export const SaveGapExplanationSchema = z.object({
  fiscal_period_id: uuid,
  voucher_series: z.string().default('A'),
  gap_start: z.number().int().positive(),
  gap_end: z.number().int().positive(),
  explanation: z.string().min(1).max(500),
})

// ============================================================
// Opening balance import schemas
// ============================================================

export const OpeningBalanceExecuteSchema = z.object({
  fiscal_period_id: uuid,
  lines: z.array(z.object({
    account_number: accountNumber,
    debit_amount: nonNegativeAmount,
    credit_amount: nonNegativeAmount,
  })).min(2, 'At least two lines are required for double-entry'),
})

// ============================================================
// Salary schemas
// ============================================================

export const EmploymentTypeSchema = z.enum(['employee', 'company_owner', 'board_member'])
export const SalaryTypeSchema = z.enum(['monthly', 'hourly'])
export const FSkattStatusSchema = z.enum(['a_skatt', 'f_skatt', 'fa_skatt', 'not_verified'])
export const VacationRuleSchema = z.enum(['procentregeln', 'sammaloneregeln'])
export const SalaryRunStatusSchema = z.enum(['draft', 'review', 'approved', 'paid', 'booked', 'corrected'])

export const SalaryLineItemTypeSchema = z.enum([
  'monthly_salary', 'hourly_salary', 'overtime', 'bonus', 'commission',
  'gross_deduction_pension', 'gross_deduction_other',
  'benefit_car', 'benefit_housing', 'benefit_meals', 'benefit_wellness', 'benefit_other',
  'sick_karens', 'sick_day2_14', 'sick_day15_plus',
  'vab', 'parental_leave', 'vacation',
  'traktamente_taxfree', 'traktamente_taxable',
  'mileage_taxfree', 'mileage_taxable',
  'net_deduction_advance', 'net_deduction_union', 'net_deduction_benefit_payment',
  'net_deduction_other',
  'correction', 'other',
])

// Base employee object (no refinements — safe for .partial())
const EmployeeSchemaBase = z.object({
  first_name: z.string().min(1).max(200),
  last_name: z.string().min(1).max(200),
  personnummer: z.string().regex(/^\d{12}$/, 'Personnummer måste vara 12 siffror (ÅÅÅÅMMDDNNNN)'),
  employment_type: EmploymentTypeSchema.default('employee'),
  employment_start: isoDate,
  employment_end: isoDate.optional(),
  employment_degree: z.number().min(1).max(100).default(100),
  salary_type: SalaryTypeSchema.default('monthly'),
  monthly_salary: z.number().nonnegative().optional(),
  hourly_rate: z.number().nonnegative().optional(),
  tax_table_number: z.number().int().min(29).max(42).optional(),
  tax_column: z.number().int().min(1).max(6).default(1),
  tax_municipality: z.string().max(100).optional(),
  is_sidoinkomst: z.boolean().default(false),
  f_skatt_status: FSkattStatusSchema.default('a_skatt'),
  clearing_number: z.string().max(10).optional(),
  bank_account_number: z.string().max(20).optional(),
  vacation_rule: VacationRuleSchema.default('procentregeln'),
  vacation_days_per_year: z.number().int().min(25).max(40).default(25),
  semestertillagg_rate: z.number().min(0).max(0.05).default(0.0043),
  email: z.string().email().optional(),
  phone: z.string().max(20).optional(),
  address_line1: z.string().max(200).optional(),
  postal_code: z.string().max(10).optional(),
  city: z.string().max(100).optional(),
  vaxa_stod_eligible: z.boolean().default(false),
  vaxa_stod_start: isoDate.optional(),
  vaxa_stod_end: isoDate.optional(),
})

export const CreateEmployeeSchema = EmployeeSchemaBase.superRefine((data, ctx) => {
  // Salary amount required based on salary_type
  if (data.salary_type === 'monthly' && (data.monthly_salary === undefined || data.monthly_salary === null || data.monthly_salary <= 0)) {
    ctx.addIssue({
      code: z.ZodIssueCode.custom,
      message: 'Månadslön krävs och måste vara större än 0 för månadslöneform',
      path: ['monthly_salary'],
    })
  }
  if (data.salary_type === 'hourly' && (data.hourly_rate === undefined || data.hourly_rate === null || data.hourly_rate <= 0)) {
    ctx.addIssue({
      code: z.ZodIssueCode.custom,
      message: 'Timlön krävs och måste vara större än 0 för timlöneform',
      path: ['hourly_rate'],
    })
  }

  // Tax table required for A-skatt employees (not sidoinkomst)
  if (data.f_skatt_status === 'a_skatt' && !data.is_sidoinkomst && !data.tax_table_number) {
    ctx.addIssue({
      code: z.ZodIssueCode.custom,
      message: 'Skattetabell krävs för A-skatt anställda (baseras på folkbokföringskommun)',
      path: ['tax_table_number'],
    })
  }

  // Tax municipality recommended when tax table is set
  if (data.tax_table_number && !data.tax_municipality) {
    ctx.addIssue({
      code: z.ZodIssueCode.custom,
      message: 'Folkbokföringskommun bör anges för att dokumentera skattetabellens underlag',
      path: ['tax_municipality'],
    })
  }
})

export const UpdateEmployeeSchema = EmployeeSchemaBase.partial().superRefine((data, ctx) => {
  // Only validate salary when salary_type is being changed in this update
  if (data.salary_type === 'monthly' && data.monthly_salary !== undefined && data.monthly_salary <= 0) {
    ctx.addIssue({
      code: z.ZodIssueCode.custom,
      message: 'Månadslön måste vara större än 0 för månadslöneform',
      path: ['monthly_salary'],
    })
  }
  if (data.salary_type === 'hourly' && data.hourly_rate !== undefined && data.hourly_rate <= 0) {
    ctx.addIssue({
      code: z.ZodIssueCode.custom,
      message: 'Timlön måste vara större än 0 för timlöneform',
      path: ['hourly_rate'],
    })
  }

  // If setting salary_type, require the corresponding salary field
  if (data.salary_type === 'monthly' && !('monthly_salary' in data)) {
    ctx.addIssue({
      code: z.ZodIssueCode.custom,
      message: 'Månadslön måste anges vid byte till månadslöneform',
      path: ['monthly_salary'],
    })
  }
  if (data.salary_type === 'hourly' && !('hourly_rate' in data)) {
    ctx.addIssue({
      code: z.ZodIssueCode.custom,
      message: 'Timlön måste anges vid byte till timlöneform',
      path: ['hourly_rate'],
    })
  }
})

export const CreateSalaryRunSchema = z.object({
  period_year: z.number().int().min(2020).max(2100),
  period_month: z.number().int().min(1).max(12),
  payment_date: isoDate,
  voucher_series: z.string().regex(/^[A-Z]$/, 'Verifikationsserie måste vara en bokstav A–Z').default('A'),
  notes: z.string().max(2000).optional(),
})

export const AddEmployeeToRunSchema = z.object({
  employee_id: uuid,
  hours_worked: z.number().nonnegative().optional(),
})

export const CreateSalaryLineItemSchema = z.object({
  salary_run_employee_id: uuid,
  item_type: SalaryLineItemTypeSchema,
  description: z.string().min(1).max(500),
  quantity: z.number().optional(),
  unit_price: z.number().optional(),
  amount: z.number(),
  is_taxable: z.boolean().default(true),
  is_avgift_basis: z.boolean().default(true),
  is_vacation_basis: z.boolean().default(true),
  is_gross_deduction: z.boolean().default(false),
  is_net_deduction: z.boolean().default(false),
  account_number: accountNumber.optional(),
  sort_order: z.number().int().default(0),
})

export const UpdateSalaryLineItemSchema = CreateSalaryLineItemSchema.partial().omit({ salary_run_employee_id: true })

// ============================================================
// AI agent flow schemas
// ============================================================

const BookingProposalLineSchema = z.object({
  account_number: accountNumber,
  debit_amount: nonNegativeAmount,
  credit_amount: nonNegativeAmount,
  description: z.string().min(1).max(500),
})

const BookingProposalCounterpartyTemplateSchema = z.object({
  counterparty_name: z.string().min(1).max(200),
  debit_account: accountNumber,
  credit_account: accountNumber,
  vat_treatment: VatTreatmentSchema.nullable(),
  category: TransactionCategorySchema.nullable(),
})

// Edit payload: the user's edited version of a booking proposal. Used in
// the /accept endpoint when the user adjusted accounts/VAT before approving.
export const EditBookingProposalSchema = z.object({
  lines: z.array(BookingProposalLineSchema).min(2),
  vat_treatment: VatTreatmentSchema.nullable(),
  default_private: z.boolean(),
  counterparty_template_proposal: BookingProposalCounterpartyTemplateSchema.nullable(),
  fiscal_period_id: uuid,
  entry_date: isoDate,
  description: z.string().min(1).max(500),
})

// For match proposals, editing just means picking a different transaction.
export const EditMatchProposalSchema = z.object({
  matched_transaction_id: uuid,
})

export const AcceptProposalSchema = z.object({
  version: z.number().int().nonnegative(),
  edits: z.union([EditBookingProposalSchema, EditMatchProposalSchema]).optional(),
})

// Change the matched transaction on a pending match proposal without
// accepting it. Source tells us whether the user picked one of the AI's
// own alternatives, an AI-regenerated suggestion, or a manually-chosen
// transaction — kept on edit_diff for learning signal.
export const ChangeMatchProposalSchema = z.object({
  version: z.number().int().nonnegative(),
  matched_transaction_id: uuid,
  source: z.enum(['user_alternative', 'user_manual', 'ai_regenerated']),
})

export const RejectProposalSchema = z.object({
  version: z.number().int().nonnegative(),
  reason: z.string().max(500).optional(),
})

export const BatchAcceptSchema = z.object({
  proposal_ids: z.array(uuid).min(1).max(50),
})

export const ResolveRequestSchema = z.object({
  response: z.record(z.string(), z.unknown()).optional(),
})

export const StartBackfillSchema = z.object({}).strict()

export const RememberLearningSchema = z.object({
  proposal_id: uuid,
  counterparty_name: z.string().min(1).max(200),
  debit_account: accountNumber,
  credit_account: accountNumber,
  vat_treatment: VatTreatmentSchema.nullable(),
  category: TransactionCategorySchema.nullable(),
})

export const ListProposalsQuerySchema = z.object({
  status: z
    .enum(['pending', 'accepted', 'rejected', 'skipped', 'invalidated'])
    .optional(),
  step_type: z.enum(['match', 'booking']).optional(),
  limit: z.coerce.number().int().min(1).max(100).default(20),
  offset: z.coerce.number().int().min(0).default(0),
})