#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 System.Globalization;
using System.Diagnostics.CodeAnalysis;

namespace log4net.Util
{
  /// <summary>
  /// Adapter that extends <see cref="TextWriter"/> and forwards all
  /// messages to an instance of <see cref="TextWriter"/>.
  /// </summary>
  /// <author>Nicko Cadell</author>
  public abstract class TextWriterAdapter : TextWriter
  {
    /// <summary>
    /// Creates an instance of <see cref="TextWriterAdapter"/> that forwards all
    /// messages to a <see cref="TextWriter"/>.
    /// </summary>
    /// <param name="writer">The <see cref="TextWriter"/> to forward to</param>
    protected TextWriterAdapter(TextWriter writer) : base(CultureInfo.InvariantCulture)
    {
      Writer = writer;
    }

    /// <summary>
    /// Gets or sets the underlying <see cref="TextWriter" />.
    /// </summary>
    protected TextWriter Writer { get; set; }

    /// <summary>
    /// The <see cref="Encoding"/> in which the output is written
    /// </summary>
    public override Encoding Encoding => Writer.Encoding;

    /// <summary>
    /// Gets an object that controls formatting
    /// </summary>
    public override IFormatProvider FormatProvider => Writer.FormatProvider;

    /// <summary>
    /// Gets or sets the line terminator string used by the TextWriter.
    /// </summary>
    [AllowNull]
    public override string NewLine
    {
      get => Writer.NewLine;
      set => Writer.NewLine = value;
    }

    /// <summary>
    /// Closes the writer and releases any system resources associated with the writer
    /// </summary>
    /// <remarks>
    /// <para>
    /// </para>
    /// </remarks>
    public override void Close() => Writer.Close();

    /// <summary>
    /// Dispose this writer
    /// </summary>
    /// <param name="disposing">flag indicating if we are being disposed</param>
    /// <remarks>
    /// <para>
    /// Dispose this writer
    /// </para>
    /// </remarks>
    protected override void Dispose(bool disposing)
    {
      if (disposing)
      {
        (Writer as IDisposable)?.Dispose();
      }
    }

    /// <summary>
    /// Flushes any buffered output
    /// </summary>
    /// <remarks>
    /// <para>
    /// Clears all buffers for the writer and causes any buffered data to be written 
    /// to the underlying device
    /// </para>
    /// </remarks>
    public override void Flush() => Writer.Flush();

    /// <summary>
    /// Writes a character to the wrapped TextWriter
    /// </summary>
    /// <param name="value">the value to write to the TextWriter</param>
    /// <remarks>
    /// <para>
    /// Writes a character to the wrapped TextWriter
    /// </para>
    /// </remarks>
    public override void Write(char value) => Writer.Write(value);

    /// <summary>
    /// Writes a character buffer to the wrapped TextWriter
    /// </summary>
    /// <param name="buffer">the data buffer</param>
    /// <param name="index">the start index</param>
    /// <param name="count">the number of characters to write</param>
    /// <remarks>
    /// <para>
    /// Writes a character buffer to the wrapped TextWriter
    /// </para>
    /// </remarks>
    public override void Write(char[] buffer, int index, int count) => Writer.Write(buffer, index, count);

    /// <summary>
    /// Writes a string to the wrapped TextWriter
    /// </summary>
    /// <param name="value">the value to write to the TextWriter</param>
    /// <remarks>
    /// <para>
    /// Writes a string to the wrapped TextWriter
    /// </para>
    /// </remarks>
    public override void Write(string? value) => Writer.Write(value);
  }
}
