HostObject.cs

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using System;
using Microsoft.ClearScript.Util;

namespace Microsoft.ClearScript
{
    internal class HostObject : HostTarget
    {
        private readonly object target;
        private readonly Type type;

        protected HostObject(object target, Type type)
        {
            this.target = target;
            this.type = type ?? target.GetType();
        }

        public static HostObject Wrap(object target)
        {
            return Wrap(target, null);
        }

        public static HostObject Wrap(object target, Type type)
        {
            return (target != null) ? new HostObject(target, type) : null;
        }

        public static object WrapResult<T>(T result)
        {
            return WrapResult(result, typeof(T));
        }

        public static object WrapResult(object result, Type type)
        {
            if (result == null)
            {
                return null;
            }

            if ((result is HostItem) || (result is HostTarget))
            {
                return result;
            }

            if ((type == typeof(void)) || (type == typeof(object)))
            {
                return result;
            }

            if ((type == result.GetType()) || (Type.GetTypeCode(type) != TypeCode.Object))
            {
                return result;
            }

            return Wrap(result, type);
        }

        #region Object overrides

        public override string ToString()
        {
            if ((target is ScriptItem) && (typeof(ScriptItem).IsAssignableFrom(type)))
            {
                return "ScriptItem";
            }

            var objectName = target.GetFriendlyName(type);
            return MiscHelpers.FormatInvariant("HostObject:{0}", objectName);
        }

        #endregion

        #region HostTarget overrides

        public override Type Type
        {
            get { return type; }
        }

        public override object Target
        {
            get { return target; }
        }

        public override object InvokeTarget
        {
            get { return target; }
        }

        public override object DynamicInvokeTarget
        {
            get { return target; }
        }

        public override HostTargetFlags Flags
        {
            get { return HostTargetFlags.AllowInstanceMembers | HostTargetFlags.AllowExtensionMethods; }
        }

        #endregion
    }
}