using System.IO;
using System.Linq;
using Chernobyl.Config;
using Chernobyl.Dependency;
using Chernobyl.IO;
using Chernobyl.Resources;
using NUnit.Framework;

namespace Chernobyl.Reflection.Template.CodeDom
{
    /// <summary>
    /// A helper class for test classes that test CodeDom Fall file processing.
    /// </summary>
    public class CodeDomTestUtility
    {
        public CodeDomTestUtility()
        {
            _core = new Core(new SearchPaths(".", "../../../"));
            _codeDomProcessor = _core.ComponentProcessor.First();
            _core.Services.Inject<CodeDomTestUtility>(this);
        }

        [Inject]
        public ISearchPaths SearchPaths
        {
            set
            {
                value.Add("../../../Chernobyl.Test/Reflection/Template/data/instance");
            }
        }

        /// <summary>
        /// A helper method that creates an <see cref="IInstance"/> from a file.
        /// </summary>
        /// <param name="filepath">The path to the file to load the
        /// <see cref="IInstance"/> from.</param>
        /// <returns>The <see cref="IInstance"/> that was created from the file.</returns>
        public IInstance FromFile(string filepath)
        {
            IInstance instance = null;
            using (FileSearchStream fileStream = new FileSearchStream(_core.Services, filepath, FileMode.Open))
            {
                _codeDomProcessor.From(result => instance = (IInstance)result.Resource, fileStream);
            }
            return instance;
        }

        IResourceProcessor<IComponent> _codeDomProcessor;
        Core _core;
    }
}