import { api } from '@/lib/api'
import type { SysConfigResponse } from '@/types/api'

// ─── Item tracking feature keys (must match Distribution.Features.SysConfig.SysConfigService) ──

export const ITEM_TRACKING_KEYS = {
  serialNumberTracking: 'Feature.SerialNumberTracking',
  batchTracking: 'Feature.BatchTracking',
  expiryDateTracking: 'Feature.ExpiryDateTracking',
  warrantyTracking: 'Feature.WarrantyTracking',
  customWarrantyOverride: 'Feature.CustomWarrantyOverride',
  defaultWarrantyPeriodDays: 'Feature.DefaultWarrantyPeriodDays',
} as const

export const sysConfig = {
  getAll: () =>
    api.get<SysConfigResponse[]>('/sys-config').then(r => r.data),

  get: (key: string) =>
    api.get<SysConfigResponse>(`/sys-config/${key}`).then(r => r.data),

  set: (key: string, value: string, userId?: string | null) =>
    api.put<SysConfigResponse>(`/sys-config/${key}`, { value, userId }).then(r => r.data),
}

// ─── GRN tax settings (must match Distribution.Features.SysConfig.SysConfigService) ──────────

export type TaxMode = 'Disabled' | 'Optional' | 'Mandatory'

export const GRN_TAX_KEYS = {
  vatMode: 'Grn.Tax.Vat.Mode',
  vatRate: 'Grn.Tax.Vat.DefaultRate',
  nbtMode: 'Grn.Tax.Nbt.Mode',
  nbtRate: 'Grn.Tax.Nbt.DefaultRate',
} as const

export interface GrnTaxSettings {
  vatMode: TaxMode
  vatDefaultRate: number
  nbtMode: TaxMode
  nbtDefaultRate: number
}

const TAX_MODES: TaxMode[] = ['Disabled', 'Optional', 'Mandatory']

/** Unconfigured, VAT is Optional (as GRNs behaved before the setting existed) and NBT is off. */
export const DEFAULT_GRN_TAX_SETTINGS: GrnTaxSettings = {
  vatMode: 'Optional',
  vatDefaultRate: 0,
  nbtMode: 'Disabled',
  nbtDefaultRate: 0,
}

export function parseGrnTaxSettings(byKey: Record<string, string>): GrnTaxSettings {
  const mode = (raw: string | undefined, fallback: TaxMode): TaxMode =>
    TAX_MODES.includes(raw as TaxMode) ? (raw as TaxMode) : fallback
  const rate = (raw: string | undefined) => {
    const n = Number(raw)
    return raw !== undefined && Number.isFinite(n) && n >= 0 && n <= 100 ? n : 0
  }
  return {
    vatMode: mode(byKey[GRN_TAX_KEYS.vatMode], DEFAULT_GRN_TAX_SETTINGS.vatMode),
    vatDefaultRate: rate(byKey[GRN_TAX_KEYS.vatRate]),
    nbtMode: mode(byKey[GRN_TAX_KEYS.nbtMode], DEFAULT_GRN_TAX_SETTINGS.nbtMode),
    nbtDefaultRate: rate(byKey[GRN_TAX_KEYS.nbtRate]),
  }
}

export const grnTaxSettings = {
  get: () =>
    sysConfig
      .getAll()
      .then(all => parseGrnTaxSettings(Object.fromEntries(all.map(c => [c.key, c.value])))),
}