// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information
// 
// 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.
// 

using System;
using System.IO;
using System.Text;

using log4net.Util;
using log4net.Core;

namespace log4net.Layout
{
    /// <summary>
    /// A very simple layout
    /// </summary>
    /// <remarks>
    /// <para>
    /// SimpleLayout consists of the level of the log statement,
    /// followed by " - " and then the log message itself. For example,
    /// <code>
    /// DEBUG - Hello world
    /// </code>
    /// </para>
    /// </remarks>
    /// <author>Nicko Cadell</author>
    /// <author>Gert Driesen</author>
    public class SimpleLayout : LayoutSkeleton
    {
        /// <summary>
        /// Constructs a SimpleLayout
        /// </summary>
        public SimpleLayout()
        {
            this.IgnoresException = true;
        }

        /// <summary>
        /// Initialize layout options
        /// </summary>
        /// <remarks>
        /// <para>
        /// This is part of the <see cref="IOptionHandler"/> delayed object
        /// activation scheme. The <see cref="ActivateOptions"/> method must 
        /// be called on this object after the configuration properties have
        /// been set. Until <see cref="ActivateOptions"/> is called this
        /// object is in an undefined state and must not be used. 
        /// </para>
        /// <para>
        /// If any of the configuration properties are modified then 
        /// <see cref="ActivateOptions"/> must be called again.
        /// </para>
        /// </remarks>
        public override void ActivateOptions() 
        {
            // nothing to do.
        }

        /// <summary>
        /// Produces a simple formatted output.
        /// </summary>
        /// <param name="loggingEvent">the event being logged</param>
        /// <param name="writer">The TextWriter to write the formatted event to</param>
        /// <remarks>
        /// <para>
        /// Formats the event as the level of the even,
        /// followed by " - " and then the log message itself. The
        /// output is terminated by a newline.
        /// </para>
        /// </remarks>
        public override void Format(TextWriter writer, LoggingEvent loggingEvent) 
        {
            if (loggingEvent == null)
            {
                throw new ArgumentNullException("loggingEvent");
            }

            writer.Write(loggingEvent.Level.DisplayName);
            writer.Write(" - ");
            loggingEvent.WriteRenderedMessage(writer);
            writer.WriteLine();
        }
    }
}
