// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

namespace ILAssembler
{
    internal static class NameHelpers
    {
        public static (string Namespace, string Name) SplitDottedNameToNamespaceAndName(string dottedName)
        {
            int lastDotIndex = dottedName.LastIndexOf('.');

            if (lastDotIndex > 0 && dottedName[lastDotIndex - 1] == '.')
            {
                // Handle cases like "a.b..ctor".
                lastDotIndex -= 1;
            }

            // A dot at position 0 is part of the name (e.g., ".GlobalStruct"), not a namespace separator
            if (lastDotIndex <= 0)
            {
                return (string.Empty, dottedName);
            }

            return (
                dottedName.Substring(0, lastDotIndex),
                dottedName.Substring(lastDotIndex + 1));
        }
    }
}