#region Apache License
//
// Licensed to the Apache Software Foundation (ASF) under one or more 
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership. 
// The ASF licenses this file to you under the Apache License, Version 2.0
// (the "License"); you may not use this file except in compliance with 
// the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// 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.Text;
using System.IO;

using log4net.Core;
using log4net.Util;
using log4net.DateFormatter;

namespace log4net.Layout.Pattern
{
	/// <summary>
	/// Write the TimeStamp to the output
	/// </summary>
	/// <remarks>
	/// <para>
	/// Date pattern converter, uses a <see cref="IDateFormatter"/> to format 
	/// the date of a <see cref="LoggingEvent"/>.
	/// </para>
	/// <para>
	/// Uses a <see cref="IDateFormatter"/> to format the <see cref="LoggingEvent.TimeStamp"/> 
	/// in Universal time.
	/// </para>
	/// <para>
	/// See the <see cref="DatePatternConverter"/> for details on the date pattern syntax.
	/// </para>
	/// </remarks>
	/// <seealso cref="DatePatternConverter"/>
	/// <author>Nicko Cadell</author>
	internal class UtcDatePatternConverter : DatePatternConverter
	{
		/// <summary>
		/// Write the TimeStamp to the output
		/// </summary>
		/// <param name="writer"><see cref="TextWriter" /> that will receive the formatted result.</param>
		/// <param name="loggingEvent">the event being logged</param>
		/// <remarks>
		/// <para>
		/// Pass the <see cref="LoggingEvent.TimeStamp"/> to the <see cref="IDateFormatter"/>
		/// for it to render it to the writer.
		/// </para>
		/// <para>
		/// The <see cref="LoggingEvent.TimeStamp"/> passed is in the local time zone, this is converted
		/// to Universal time before it is rendered.
		/// </para>
		/// </remarks>
		/// <seealso cref="DatePatternConverter"/>
		override protected void Convert(TextWriter writer, LoggingEvent loggingEvent)
		{
			try 
			{
				m_dateFormatter.FormatDate(loggingEvent.TimeStamp.ToUniversalTime(), writer);
			}
			catch (Exception ex) 
			{
				LogLog.Error(declaringType, "Error occurred while converting date.", ex);
			}
		}

	    #region Private Static Fields

	    /// <summary>
	    /// The fully qualified type of the UtcDatePatternConverter class.
	    /// </summary>
	    /// <remarks>
	    /// Used by the internal logger to record the Type of the
	    /// log message.
	    /// </remarks>
	    private readonly static Type declaringType = typeof(UtcDatePatternConverter);

	    #endregion Private Static Fields
	}
}