import {
  registerDecorator,
  ValidationArguments,
  ValidationOptions,
  ValidatorConstraint,
  ValidatorConstraintInterface,
} from "class-validator";
import {
  REPAIR_LINE_AMOUNT_TOMAN,
} from "src/constants/repair-amount-limits";
import { parseMoneyAmountToman } from "src/utils/unicode-digits";

export type RepairLineAmountTomanOptions = {
  /** When true, `0` is valid (e.g. expert `price` / `salary` split where one side is zero). */
  allowZero?: boolean;
};

@ValidatorConstraint({ name: "isRepairLineAmountToman", async: false })
export class IsRepairLineAmountTomanConstraint
  implements ValidatorConstraintInterface
{
  validate(value: unknown, args: ValidationArguments): boolean {
    const [minToman, maxToman, allowZero] = args.constraints as [
      number,
      number,
      boolean | undefined,
    ];
    if (value == null || value === "") return true;
    const amount = parseMoneyAmountToman(value);
    if (amount == null) return false;
    if (allowZero && amount === 0) return true;
    return amount >= minToman && amount <= maxToman;
  }

  defaultMessage(args: ValidationArguments): string {
    const [minToman, maxToman, allowZero] = args.constraints as [
      number,
      number,
      boolean | undefined,
    ];
    const zeroHint = allowZero ? " Use 0 where one side of price/salary is unused." : "";
    return (
      `Amount must be in Toman between ${minToman.toLocaleString("en-US")} and ${maxToman.toLocaleString("en-US")}.${zeroHint}`
    );
  }
}

/** Optional repair-line amount in Toman (digits only after unicode normalize). */
export function IsRepairLineAmountToman(
  options?: ValidationOptions & RepairLineAmountTomanOptions,
) {
  const { allowZero, ...validationOptions } = options ?? {};
  return (object: object, propertyName: string) => {
    registerDecorator({
      target: object.constructor,
      propertyName,
      options: validationOptions,
      constraints: [
        REPAIR_LINE_AMOUNT_TOMAN.MIN,
        REPAIR_LINE_AMOUNT_TOMAN.MAX,
        allowZero === true,
      ],
      validator: IsRepairLineAmountTomanConstraint,
    });
  };
}