using System;

namespace ExtendedBox.Reflection;

public static class TypeExtensions
{
    public static bool IsAssignableToGenericType(this Type givenType, Type genericType)
    {
        if(TypeLibrary.GetType(genericType) is null)
            throw new InvalidOperationException($"Using TypeLibrary with type {genericType.FullName} is blocked by whitelist.");

        var interfaceTypes = givenType.GetInterfaces();

        foreach(var interfaceType in interfaceTypes)
        {
            if(interfaceType.IsGenericType)
            {
                var genericTypeDefinition = TypeLibrary.GetType(interfaceType)?.TargetType;
                if(genericTypeDefinition is not null && genericTypeDefinition == genericType)
                    return true;
            }
        }

        if(givenType.IsGenericType)
        {
            var genericTypeDefinition = TypeLibrary.GetType(givenType)?.TargetType;
            if(genericTypeDefinition is not null && genericTypeDefinition == genericType)
                return true;
        }

        Type? baseType = givenType.BaseType;
        if(baseType == null)
            return false;

        return baseType.IsAssignableToGenericType(genericType);
    }
}