public string GetHeaderValue(string useragent)
        {
            var        agent   = new Useragent(useragent);
            CspVersion version = agent.IsFirefox() ? CspVersion.Ff4To7 : CspVersion.Latest;

            return(_policyDirectives
                   .OrderBy(p => p.GetDirectiveName(version) == "options" ? "1" : ("2" + p.GetDirectiveName(version)))
                   .Select(p => p.ToHeaderString(version))
                   .Where(s => !string.IsNullOrEmpty(s))
                   .Aggregate((s1, s2) => s1 + "; " + s2)
                   + ReportUriPart);
        }
        public string GetHeaderValue(string useragent)
        {
            var agent = new Useragent(useragent);
            CspVersion version = agent.IsFirefox() ? CspVersion.Ff4To7 : CspVersion.Latest;
            return _policyDirectives
                .OrderBy(p => p.GetDirectiveName(version) == "options" ? "1" : ("2" + p.GetDirectiveName(version)))
                .Select(p => p.ToHeaderString(version))
                .Where(s => !string.IsNullOrEmpty(s))
                .Aggregate((s1, s2) => s1 + "; " + s2)
                + ReportUriPart;

        }