// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using System.Reflection;

namespace System.Linq.Expressions
{
    /// <summary>
    /// Describes the binding types that are used in MemberInitExpression objects.
    /// </summary>
    public enum MemberBindingType
    {
        /// <summary>
        /// A binding that represents initializing a member with the value of an expression.
        /// </summary>
        Assignment,
        /// <summary>
        /// A binding that represents recursively initializing members of a member.
        /// </summary>
        MemberBinding,
        /// <summary>
        /// A binding that represents initializing a member of type <see cref="Collections.IList"/> or <see cref="Collections.Generic.ICollection{T}"/> from a list of elements.
        /// </summary>
        ListBinding
    }

    /// <summary>
    /// Provides the base class from which the classes that represent bindings that are used to initialize members of a newly created object derive.
    /// </summary>
    public abstract class MemberBinding
    {
        /// <summary>
        /// Initializes an instance of <see cref="MemberBinding"/> class.
        /// </summary>
        /// <param name="type">The type of member binding.</param>
        /// <param name="member">The field or property to be initialized.</param>
        [Obsolete("Do not use this constructor. It will be removed in future releases.")]
        protected MemberBinding(MemberBindingType type, MemberInfo member)
        {
            BindingType = type;
            Member = member;
        }

        /// <summary>
        /// Gets the type of binding that is represented.
        /// </summary>
        public MemberBindingType BindingType { get; }

        /// <summary>
        /// Gets the field or property to be initialized.
        /// </summary>
        public MemberInfo Member { get; }

        /// <summary>
        /// Returns a <see cref="String"/> that represents the current <see cref="Object"/>.
        /// </summary>
        /// <returns>A <see cref="String"/> that represents the current <see cref="Object"/>.</returns>
        public override string ToString()
        {
            return ExpressionStringBuilder.MemberBindingToString(this);
        }

        internal virtual void ValidateAsDefinedHere(int index) => throw Error.UnknownBindingType(index);
    }
}
