Engine.cs

#region Copyright
// *******************************************************************************
// Copyright (c) 2000-2011 Paul Stancer.
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// which accompanies this distribution, and is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// Contributors:
//     Paul Stancer - initial implementation
// *******************************************************************************
#endregion
#region using
using System;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using System.Text;

using Stancer.GTFSEngine.Entities;

using Ximura;
#endregion  
namespace Stancer.GTFSEngine
{
    public partial class Engine
    {
        #region Declarations
        private object mSyncLock = new object();

        private ISourceDataCollection mData;
        #endregion

        #region Constructor
        /// <summary>
        /// This is the default constructor.
        /// </summary>
        /// <param name="data">The data source collection.</param>
        public Engine(ISourceDataCollection data)
        {
            mData = data;
        }
        #endregion

        #region HasTransitData(TransitFileType tType)
        /// <summary>
        /// This function checks whether there is valid data for the specific transit type.
        /// </summary>
        /// <param name="tType">The transit type.</param>
        /// <returns>Returns true if there is valid data.</returns>
        private bool HasTransitData(TransitFileType tType)
        {
            return mData.HasStream(tType);
        }
        #endregion

        #region TransitEntityEnum(TransitFileType tType, IEnumerable<KeyValuePair<string,bool>> headers, Func<CSVRowItem,T> conv)
        /// <summary>
        /// This method returns the entity items from the CSV data file collection.
        /// </summary>
        /// <typeparam name="T">The transit entity type.</typeparam>
        /// <param name="tType">The transit file type.</param>
        /// <param name="headersRequired">The required headers.</param>
        /// <param name="conv">The conversion function.</param>
        /// <returns>Returns an amalgamated collection of entities.</returns>
        private IEnumerable<T> TransitEntityEnum<T>(
            TransitFileType tType, IEnumerable<KeyValuePair<string,bool>> headers, Func<CSVRowItem,T> conv)
        {
            if (!HasTransitData(tType))
                yield break;

            using (Stream data = mData.GetStream(tType))
            {
                if (data == null)
                    throw new ArgumentNullException();

                CSVStreamOptions opts = new CSVStreamOptions(Encoding.UTF8, ',', true, false, null, null);

                CSVStreamEnumerator<T> item = new CSVStreamEnumerator<T>(data, conv, opts);

                foreach (var entity in item)
                    yield return entity;
            }
        }
        #endregion  
    }
}