using System.Reflection;

namespace Connected.Interop
{
	public static class Members
	{
		public static IEnumerable<MemberInfo> GetDataMembers(this Type type, string? name = null, bool includeNonPublic = false)
		{
			return type.GetInheritedProperites()
					 .Where(p => p.CanRead && p.GetMethod is not null && !p.GetMethod.IsStatic && (p.GetMethod.IsPublic || includeNonPublic) && (string.IsNullOrEmpty(name) || string.Equals(p.Name, name, StringComparison.Ordinal)))
					 .Cast<MemberInfo>().Concat(type.GetInheritedFields()
					 .Where(f => !f.IsStatic && (f.IsPublic || includeNonPublic) && (string.IsNullOrEmpty(name) || string.Equals(f.Name, name, StringComparison.Ordinal))));
		}

		public static MemberInfo? GetDataMember(this Type type, string name, bool includeNonPublic = false)
		{
			return type.GetDataMembers(name, includeNonPublic).FirstOrDefault();
		}

		public static IEnumerable<FieldInfo> GetInheritedFields(this Type type)
		{
			foreach (var info in type.GetInheritedTypeInfos())
			{
				foreach (var p in info.GetRuntimeFields())
					yield return p;
			}
		}

		public static Type? GetMemberType(MemberInfo mi)
		{
			if (mi is FieldInfo fi)
				return fi.FieldType;

			if (mi is PropertyInfo pi)
				return pi.PropertyType;

			if (mi is EventInfo ei)
				return ei.EventHandlerType;

			if (mi is MethodInfo me)
				return me.ReturnType;

			return default;
		}

		public static bool IsReadOnly(MemberInfo member)
		{
			if (member is PropertyInfo pi)
				return !pi.CanWrite || pi.SetMethod is null;

			if (member is FieldInfo fi)
				return (fi.Attributes & FieldAttributes.InitOnly) != 0;

			return true;
		}
	}
}