import { ValidationOptions } from "../ValidationOptions";
import { buildMessage, ValidateBy } from "../common/ValidateBy";
import validator from "validator";

export const IS_DIVISIBLE_BY = "isDivisibleBy";

/**
 * Checks if value is a number that's divisible by another.
 */
export function isDivisibleBy(value: unknown, num: number): boolean {
    return typeof value === "number" &&
        typeof num === "number" &&
        validator.isDivisibleBy(String(value), num);
}

/**
 * Checks if value is a number that's divisible by another.
 */
export function IsDivisibleBy(num: number, validationOptions?: ValidationOptions): PropertyDecorator {
    return ValidateBy(
        {
            name: IS_DIVISIBLE_BY,
            constraints: [num],
            validator: {
                validate: (value, args): boolean => isDivisibleBy(value, args.constraints[0]),
                defaultMessage: buildMessage(
                    (eachPrefix) => eachPrefix + "$property must be divisible by $constraint1",
                    validationOptions
                )
            }
        },
        validationOptions
    );
}