using System.Text.RegularExpressions;

namespace Convention.RScript.Matcher
{
    public class NamespaceMater : IRSentenceMatcher
    {
        public bool Match(string expression, ref RScriptSentence sentence)
        {
            if (expression == "{")
            {
                sentence.mode = RScriptSentence.Mode.EnterNamespace;
                return true;
            }
            else if (expression == "}")
            {
                sentence.mode = RScriptSentence.Mode.ExitNamespace;
                return true;
            }
            else if (expression.StartsWith("namespace"))
            {
                sentence.mode = RScriptSentence.Mode.NamedSpace;
                Regex regex = new(@"namespace\s*\(([a-zA-Z_][a-zA-Z0-9_]*)\)");
                var match = regex.Match(expression);
                if (match.Success)
                {
                    sentence.content = match.Groups[1].Value;
                    return true;
                }
                else
                {
                    throw new RScriptRuntimeException("Invalid namespace declaration", -1);
                }
            }
            return false;
        }
    }
}