Transformalizing NorthWind

#region License
// /*
// See license included in this library folder.
// */
#endregion

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;

namespace Transformalize.Libs.ExcelDataReader.Core.BinaryFormat
{
	/// <summary>
	/// Represents Root Directory in file
	/// </summary>
	internal class XlsRootDirectory
	{
		private readonly List<XlsDirectoryEntry> m_entries;
		private readonly XlsDirectoryEntry m_root;

		/// <summary>
		/// Creates Root Directory catalog from XlsHeader
		/// </summary>
		/// <param name="hdr">XlsHeader object</param>
		public XlsRootDirectory(XlsHeader hdr)
		{
			var stream = new XlsStream(hdr, hdr.RootDirectoryEntryStart);
			var array = stream.ReadStream();
			byte[] tmp;
			XlsDirectoryEntry entry;
			var entries = new List<XlsDirectoryEntry>();
			for (var i = 0; i < array.Length; i += XlsDirectoryEntry.Length)
			{
				tmp = new byte[XlsDirectoryEntry.Length];
				Buffer.BlockCopy(array, i, tmp, 0, tmp.Length);
				entries.Add(new XlsDirectoryEntry(tmp));
			}
			m_entries = entries;
			for (var i = 0; i < entries.Count; i++)
			{
				entry = entries[i];
				if (m_root == null && entry.EntryType == STGTY.STGTY_ROOT)
					m_root = entry;
				if (entry.ChildSid != (uint)FATMARKERS.FAT_FreeSpace)
					entry.Child = entries[(int)entry.ChildSid];
				if (entry.LeftSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
					entry.LeftSibling = entries[(int)entry.LeftSiblingSid];
				if (entry.RightSiblingSid != (uint)FATMARKERS.FAT_FreeSpace)
					entry.RightSibling = entries[(int)entry.RightSiblingSid];
			}
		}

		/// <summary>
		/// Returns all entries in Root Directory
		/// </summary>
		public ReadOnlyCollection<XlsDirectoryEntry> Entries
		{
			get { return m_entries.AsReadOnly(); }
		}

		/// <summary>
		/// Returns the Root Entry
		/// </summary>
		public XlsDirectoryEntry RootEntry
		{
			get { return m_root; }
		}

		/// <summary>
		/// Searches for first matching entry by its name
		/// </summary>
		/// <param name="EntryName">String name of entry</param>
		/// <returns>Entry if found, null otherwise</returns>
		public XlsDirectoryEntry FindEntry(string EntryName)
		{
			foreach (var e in m_entries)
			{
				if (e.EntryName == EntryName)
					return e;
			}
			return null;
		}
	}
}