DataTable Synchronization Manager

/*
Copyright (c) 2006, Marc Clifton
All rights reserved.

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this list
  of conditions and the following disclaimer. 

* Redistributions in binary form must reproduce the above copyright notice, this 
  list of conditions and the following disclaimer in the documentation and/or other
  materials provided with the distribution. 
 
* Neither the name Marc Clifton nor the names of contributors may be
  used to endorse or promote products derived from this software without specific
  prior written permission. 

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

// Other information: DataColumn data types: ms-help://MS.MSDNQTR.v80.en/MS.MSDN.v80/MS.NETDEVFX.v20.en/cpref4/html/P_System_Data_DataColumn_DataType.htm
// DataSetDateTime: ms-help://MS.MSDNQTR.v80.en/MS.MSDN.v80/MS.NETDEVFX.v20.en/cpref4/html/T_System_Data_DataSetDateTime.htm

using System;
using System.Collections.Generic;
using System.Data;

namespace Clifton.Data
{
	/// <summary>
	/// Manages the record information required to synchronize two DataTables.
	/// </summary>
	public class TransactionRecordPacket
	{
		/// <summary>
		/// An indexable list of pk field names and their pk values.
		/// </summary>
		protected Dictionary<string, object> pkValues;

		/// <summary>
		/// The record transaction type.
		/// </summary>
		protected DataTableTransactionRecord.RecordType tranType;

		/// <summary>
		/// The field name being changed (for change transactions).
		/// </summary>
		protected string columnName;

		/// <summary>
		/// The new value of the field (for change transactions).
		/// </summary>
		protected object newValue;

		/// <summary>
		/// Gets the indexable primary key field name / field value dictionary.
		/// </summary>
		public Dictionary<string, object> PrimaryKeyValues
		{
			get { return pkValues; }
		}

		/// <summary>
		/// Gets/sets the transaction type.
		/// </summary>
		public DataTableTransactionRecord.RecordType TransactionType
		{
			get { return tranType; }
			set { tranType = value; }
		}

		/// <summary>
		/// Gets/sets the column name of the changing field.
		/// </summary>
		public string ColumnName
		{
			get { return columnName; }
			set { columnName = value; }
		}

		/// <summary>
		/// Gets/sets the new value of the changing field.
		/// </summary>
		public object NewValue
		{
			get { return newValue; }
			set { newValue = value; }
		}

		/// <summary>
		/// Default constructor.
		/// </summary>
		public TransactionRecordPacket()
		{
			pkValues = new Dictionary<string, object>();
		}

		/// <summary>
		/// Constructor.
		/// </summary>
		/// <param name="record">The record to "packetize".</param>
		public TransactionRecordPacket(DataTableTransactionRecord record)
		{
			pkValues = new Dictionary<string, object>();
			tranType = record.TransactionType;

			foreach (DataColumn dc in record.Row.Table.PrimaryKey)
			{
				pkValues.Add(dc.ColumnName, record.GetGuaranteedRowValue(dc.ColumnName));
			}

			// Fill in some additional information if the transaction is a ChangeField.
			if (tranType == DataTableTransactionRecord.RecordType.ChangeField)
			{
				columnName = record.ColumnName;
				newValue = record.NewValue;
			}
		}
	}
}