export type CityPartnerScopeType = 'CITY_WIDE' | 'DISTRICT';
export type CityPartnerStatus = 'ACTIVE' | 'PAUSED';

export interface PartnerCityBindingInput {
  id?: string;
  partnerAccountId: string;
  scopeType: CityPartnerScopeType;
  districtCodes?: string[] | null;
  bindingStatus?: CityPartnerStatus;
  /** 仅用于重合报错文案 */
  companyName?: string | null;
}

export interface PartnerCityValidationResult {
  ok: boolean;
  message?: string;
}

export function validatePartnerCityBinding(
  existing: PartnerCityBindingInput[],
  input: PartnerCityBindingInput,
  excludeId?: string,
): PartnerCityValidationResult {
  const others = existing.filter((b) => b.id !== excludeId);

  if (others.some((b) => b.partnerAccountId === input.partnerAccountId)) {
    return { ok: false, message: '该合伙人已绑定此城市' };
  }

  if (input.scopeType === 'CITY_WIDE') {
    if (others.some((b) => b.scopeType === 'CITY_WIDE')) {
      return { ok: false, message: '每城最多 1 名全城合伙人' };
    }
    return { ok: true };
  }

  // 区域合伙人所选区县可为空（录入时可稍后补全）
  return { ok: true };
}

/** @deprecated use validatePartnerCityBinding */
export const validateCityPartnerBinding = validatePartnerCityBinding;

export const DEFAULT_MAX_PARTNER_COMMISSION_RATE = 0.05;

export function resolveMaxPartnerCommissionRate(maxRate?: number | null): number {
  if (maxRate == null || Number.isNaN(Number(maxRate))) {
    return DEFAULT_MAX_PARTNER_COMMISSION_RATE;
  }
  return Number(maxRate);
}

/** 订单佣金 + 核销佣金不得超过城市配置上限（默认 5%） */
export function validatePartnerCommissionRates(
  orderCommissionRate: number,
  redeemCommissionRate: number,
  maxSumRate = DEFAULT_MAX_PARTNER_COMMISSION_RATE,
): PartnerCityValidationResult {
  const sum = orderCommissionRate + redeemCommissionRate;
  const max = resolveMaxPartnerCommissionRate(maxSumRate);
  if (sum > max + 1e-9) {
    return {
      ok: false,
      message: `订单佣金与核销佣金合计不得超过 ${(max * 100).toFixed(2)}%（当前 ${(sum * 100).toFixed(2)}%）`,
    };
  }
  return { ok: true };
}

export function assertCanDeleteCityPartner(input: {
  storeCount: number;
  orderCount: number;
  redeemCount: number;
}): PartnerCityValidationResult {
  if (input.storeCount > 0) {
    return { ok: false, message: '该城市合伙人下还有门店，请先删除门店' };
  }
  if (input.orderCount > 0) {
    return { ok: false, message: '该账号下有关联订单，禁止删除' };
  }
  if (input.redeemCount > 0) {
    return { ok: false, message: '该账号下有关联核销单，禁止删除' };
  }
  return { ok: true };
}

export function assertCanDeleteStore(input: {
  orderCount: number;
  redeemCount: number;
}): PartnerCityValidationResult {
  if (input.orderCount > 0) {
    return { ok: false, message: '该账号下有关联订单，禁止删除' };
  }
  if (input.redeemCount > 0) {
    return { ok: false, message: '该账号下有关联核销单，禁止删除' };
  }
  return { ok: true };
}