using System.Collections.Generic;
using System.Linq;
using LinFu.IoC.Interfaces;

namespace LinFu.IoC
{
    /// <summary>
    ///     Represents an <see cref="IPostProcessor" /> type that processes multiple <see cref="IPostProcessor" /> instances at
    ///     once.
    /// </summary>
    internal class CompositePostProcessor : IPostProcessor
    {
        private readonly IEnumerable<IPostProcessor> _postProcessors;

        /// <summary>
        ///     Initializes the type using the given <paramref name="postProcessors" />.
        /// </summary>
        /// <param name="postProcessors">The list of <see cref="IPostProcessor" /> instances that will be handled by this type.</param>
        internal CompositePostProcessor(IEnumerable<IPostProcessor> postProcessors)
        {
            _postProcessors = postProcessors;
        }


        /// <summary>
        ///     A method that passes every request result made
        ///     to the list of postprocessors.
        /// </summary>
        /// <param name="result">
        ///     The <see cref="IServiceRequestResult" /> instance that describes the result of the service
        ///     request.
        /// </param>
        /// <returns>A <see cref="IServiceRequestResult" /> representing the results returned as a result of the postprocessors.</returns>
        public void PostProcess(IServiceRequestResult result)
        {
            // Let each postprocessor inspect 
            // the results and/or modify the 
            // returned object instance
            var postprocessors = _postProcessors.ToArray();
            foreach (var postProcessor in postprocessors)
            {
                if (postProcessor == null)
                    continue;

                postProcessor.PostProcess(result);
            }
        }
    }
}