/Source/Bifrost/Sagas/SagaLibrarian.cs

#region License

//

// Copyright (c) 2008-2012, DoLittle Studios and Komplett ASA

//

// Licensed under the Microsoft Permissive License (Ms-PL), Version 1.1 (the "License")

// With one exception :

//   Commercial libraries that is based partly or fully on Bifrost and is sold commercially, 

//   must obtain a commercial license.

//

// You may not use this file except in compliance with the License.

// You may obtain a copy of the license at 

//

//   http://bifrost.codeplex.com/license

//

// Unless required by applicable law or agreed to in writing, software

// distributed under the License is distributed on an "AS IS" BASIS,

// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

// See the License for the specific language governing permissions and

// limitations under the License.

//

#endregion



using System;

using System.Collections.Generic;

using System.Linq;

using Bifrost.Entities;



namespace Bifrost.Sagas

{

    /// <summary>

    /// Represents a <see cref="ISagaLibrarian"/>

    /// </summary>

	public class SagaLibrarian : ISagaLibrarian

	{

		readonly IEntityContext<SagaHolder> _entityContext;

		readonly ISagaConverter _sagaConverter;



        /// <summary>

        /// Initializes a new instance of <see cref="SagaLibrarian"/>

        /// </summary>

        /// <param name="entityContext">A <see cref="IEntityContext{SagaHolder}"/> to use for working with persisting and resuming <see cref="ISaga">Sagas</see></param>

        /// <param name="sagaConverter">A <see cref="ISagaConverter"/> for converting a <see cref="ISaga"/> to a <see cref="SagaHolder"/> and back</param>

		public SagaLibrarian(IEntityContext<SagaHolder> entityContext, ISagaConverter sagaConverter)

		{

			_entityContext = entityContext;

			_sagaConverter = sagaConverter;

		}



#pragma warning disable 1591 // Xml Comments

        public void Close(ISaga saga)

		{

			var sagaHolder = _sagaConverter.ToSagaHolder(saga);

			_entityContext.Delete(sagaHolder);

			_entityContext.Commit();

		}



		public void Catalogue(ISaga saga)

		{

			var sagaHolder = GetExistingIfAny(saga.Id);

			if (sagaHolder == null)

			{

				sagaHolder = _sagaConverter.ToSagaHolder(saga);

				_entityContext.Insert(sagaHolder);

			}

			else

			{

				_sagaConverter.Populate(sagaHolder, saga);

				_entityContext.Update(sagaHolder);

			}

			_entityContext.Commit();

		}



		public ISaga Get(Guid id)

		{

			var sagaHolder = (from s in _entityContext.Entities

								  where s.Id == id

								  select s).SingleOrDefault();

			var saga = _sagaConverter.ToSaga(sagaHolder);

			return saga;

		}





		public ISaga Get(string partition, string key)

		{

			var query = from s in _entityContext.Entities

			            where s.Partition == partition && s.Key == key

			            select _sagaConverter.ToSaga(s);



			return query.SingleOrDefault();

		}



		public IEnumerable<ISaga> GetForPartition(string partition)

		{

			var sagaHolders = (from s in _entityContext.Entities

			                      where s.Partition == partition

			                      select s).ToArray();

			var sagas = sagaHolders.Select(_sagaConverter.ToSaga);

			return sagas;

		}

#pragma warning restore 1591 // Xml Comments





        SagaHolder GetExistingIfAny(Guid id)

		{

			var sagaHolder = (from s in _entityContext.Entities

								  where s.Id == id

								  select s).SingleOrDefault();

			return sagaHolder;

		}

	}

}