var esig_validation = {
    is_email: function (email_address) {
        var filter = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;
        if (filter.test(email_address)) {
            return true;
        } else {
            return false;
        }
    },
    is_string: function (input_string) {

        // check string is not empty
        if (input_string === "") {
            return false;
        }
        // check string is not empty
        if (!input_string) {
            return false;
        }
        // check string is not undefined and not null
        if(typeof(input_string) === "undefined" && input_string === null)
        {
            return false;
        }

        // Regex to check valid HTML tag.
        const regexPattern = new RegExp("<(\"[^\"]*\"|'[^']*'|[^'\">])*>") ;
        // check string for html tags.
        if (regexPattern.test(input_string))
        {
            // no html
            return false;
        }

        return true;
    },
    is_fullName: function (value) {
        // check for double spaces.
        if (/\s{2}/.test(value)) return false;
        // Emoji validation
        const regexExpEmoji = /(©|®|[ -㌀]|\ud83c[퀀-\udfff]|\ud83d[퀀-\udfff]|\ud83e[퀀-\udfff])/gi;
        if (regexExpEmoji.test(value)) return false;
        // name validation: allow letters (incl. accented), hyphens, apostrophes, periods, commas, and spaces
        const regexp = new RegExp(/^[^_!¡?÷?¿\\+=@#$%ˆ*{}|~<>;:[\]]([-'.,]?[^_!¡?÷?¿\\+=@#$%ˆ*{}|~<>;:[\]]+)*( [^_!¡?÷?¿\\+=@#$%ˆ*{}|~<>;:[\]]([-'.,]?[^_!¡?÷?¿\\+=@#$%ˆ*{}|~<>;:[\]]+)*)*$/i);
        return regexp.test(value);

    },
};


(function ($) {

    $.validator.addMethod("esiglegalname", function (value, element) {

        const japanesRegex = /[　-〿]|[぀-ゟ]|[゠-ヿ]|[＀-￯]|[一-龯]|[★-☆]|[←-↕]|※/g;

        if(japanesRegex.test(value)) {
            return this.optional(element) || japanesRegex.test(value);
        }

        // check for double spaces
        if (/\s{2}/.test(value)) return false;

        // emoji validation
        const regexExpEmoji = /(©|®|[ -㌀]|\ud83c[퀀-\udfff]|\ud83d[퀀-\udfff]|\ud83e[퀀-\udfff])/gi;
        if (regexExpEmoji.test(value)) return false;

        // name validation: allow letters (incl. accented), hyphens, apostrophes, periods, commas, and spaces
        const regexp = new RegExp(/^[^_!¡?÷?¿\\+=@#$%ˆ*{}|~<>;:[\]]([-'.,]?[^_!¡?÷?¿\\+=@#$%ˆ*{}|~<>;:[\]]+)*( [^_!¡?÷?¿\\+=@#$%ˆ*{}|~<>;:[\]]([-'.,]?[^_!¡?÷?¿\\+=@#$%ˆ*{}|~<>;:[\]]+)*)*$/i);
        return this.optional(element) || regexp.test(value);

    }, "A valid name is required to sign this document");

})(jQuery);