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

export const MIN_LENGTH = "minLength";

/**
 * Checks if the string's length is not less than given number. Note: this function takes into account surrogate pairs.
 * If given value is not a string, then it returns false.
 */
export function minLength(value: unknown, min: number): boolean {
    return typeof value === "string" && validator.isLength(value, { min });
}

/**
 * Checks if the string's length is not less than given number. Note: this function takes into account surrogate pairs.
 * If given value is not a string, then it returns false.
 */
export function MinLength(min: number, validationOptions?: ValidationOptions): PropertyDecorator {
    return ValidateBy(
        {
            name: MIN_LENGTH,
            constraints: [min],
            validator: {
                validate: (value, args): boolean => minLength(value, args.constraints[0]),
                defaultMessage: buildMessage(
                    (eachPrefix) => eachPrefix + "$property must be longer than or equal to $constraint1 characters",
                    validationOptions
                )
            }
        },
        validationOptions
    );
}