#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 log4net.Util.TypeConverters;

namespace log4net.Layout
{
  /// <summary>
  /// Type converter for the <see cref="IRawLayout"/> interface
  /// </summary>
  /// <remarks>
  /// <para>
  /// Used to convert objects to the <see cref="IRawLayout"/> interface.
  /// Supports converting from the <see cref="ILayout"/> interface to
  /// the <see cref="IRawLayout"/> interface using the <see cref="Layout2RawLayoutAdapter"/>.
  /// </para>
  /// </remarks>
  /// <author>Nicko Cadell</author>
  /// <author>Gert Driesen</author>
  public class RawLayoutConverter : IConvertFrom
  {
    #region Override Implementation of IRawLayout

    /// <summary>
    /// Can the sourceType be converted to an <see cref="IRawLayout"/>
    /// </summary>
    /// <param name="sourceType">the source to be to be converted</param>
    /// <returns><c>true</c> if the source type can be converted to <see cref="IRawLayout"/></returns>
    /// <remarks>
    /// <para>
    /// Test if the <paramref name="sourceType"/> can be converted to a
    /// <see cref="IRawLayout"/>. Only <see cref="ILayout"/> is supported
    /// as the <paramref name="sourceType"/>.
    /// </para>
    /// </remarks>
    public bool CanConvertFrom(Type sourceType)
    {
      // Accept an ILayout object
      return (typeof(ILayout).IsAssignableFrom(sourceType));
    }

    /// <summary>
    /// Convert the value to a <see cref="IRawLayout"/> object
    /// </summary>
    /// <param name="source">the value to convert</param>
    /// <returns>the <see cref="IRawLayout"/> object</returns>
    /// <remarks>
    /// <para>
    /// Convert the <paramref name="source"/> object to a 
    /// <see cref="IRawLayout"/> object. If the <paramref name="source"/> object
    /// is a <see cref="ILayout"/> then the <see cref="Layout2RawLayoutAdapter"/>
    /// is used to adapt between the two interfaces, otherwise an
    /// exception is thrown.
    /// </para>
    /// </remarks>
    public object ConvertFrom(object source)
    {
      ILayout layout = source as ILayout;
      if (layout != null)
      {
        return new Layout2RawLayoutAdapter(layout);
      }
      throw ConversionNotSupportedException.Create(typeof(IRawLayout), source);
    }

    #endregion
  }
}