using System;
using System.Linq.Expressions;

namespace MyCode.Project.Infrastructure
{
    /// <summary>
    /// Represents the combined specification which indicates that either of the given
    /// specification should be satisfied by the given object.
    /// </summary>
    /// <typeparam name="T">The type of the object to which the specification is applied.</typeparam>
    public class OrSpecification<T> : CompositeSpecification<T>
    {
        #region Ctor
        /// <summary>
        /// Initializes a new instance of <c>OrSpecification&lt;T&gt;</c> class.
        /// </summary>
        /// <param name="left">The first specification.</param>
        /// <param name="right">The second specification.</param>
        public OrSpecification(ISpecification<T> left, ISpecification<T> right) : base(left, right) { }
        #endregion

        #region Public Methods
        /// <summary>
        /// Gets the LINQ expression which represents the current specification.
        /// </summary>
        /// <returns>The LINQ expression.</returns>
        public override Expression<Func<T, bool>> GetExpression()
        {
            //var body = Expression.OrElse(Left.GetExpression().Body, Right.GetExpression().Body);
            //return Expression.Lambda<Func<T, bool>>(body, Left.GetExpression().Parameters);
            return Left.GetExpression().Or(Right.GetExpression());
        }
        #endregion
    }
}