// Copyright (c) 2009 The Chromium Authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file.

package org.chromium.sdk;

import java.io.Writer;

/**

 * Logger facility for the Chromium debugger connection. It can eavesdrop both

 * incoming and outgoing streams and log them somewhere. To make other code

 * less dependent on this interface, it works by wrapping reader/writer and is

 * only visible at start-up time. This approach has its disadvantages, because

 * it works with raw data streams, which are not perfectly formatted for human

 * reading. E.g. adjacent  requests or responses are not separated even

 * by EOL.

 */

public interface ConnectionLogger {

  /**

   * @return new writer that should pass all data to {@code streamWriter} and

   * silently copy it elsewhere (without additional exceptions).

   */

  LoggableWriter wrapWriter(LoggableWriter streamWriter);

  /**

   * @return new reader that should give access to all data

   * from {@code streamReader} and silently copy it elsewhere (without

   * additional exceptions).

   */

  LoggableReader wrapReader(LoggableReader streamReader);

  /**

   * Connection may allow the logger to close it. It is nice for UI, where

   * user sees logger and the corresponding stop button.

   * TODO(peter.rybin): consider removing it out of logging.

   */

  void setConnectionCloser(ConnectionCloser connectionCloser);

  /**

   * Interface that gives you control over underlying connection.

   */

  interface ConnectionCloser {

    void closeConnection();

  }

  /**

   * Notifies logger that actual transmission is starting. After this {@link #handleEos()}

   * is guaranteed to be called.

   */

  void start();

  /**

   * Notifies logger that EOS has been received from remote. Technically some

   * traffic still may go through writer (i.e. be sent to remote) after this.

   */

  void handleEos();

  /**

   * Factory for connection logger. ConnectionLogger is NOT reconnectable.

   */

  interface Factory {

    /**

     * Creates new instance of {@link ConnectionLogger}.

     */

    ConnectionLogger newConnectionLogger();

  }

  /**

   * Reader that allows client to add marks to stream. These marks may become visible in log

   * console.

   */

  interface LoggableReader {

    LineReader getReader();

    /**

     * Add log mark at current reader's position.

     */

    void markSeparatorForLog();

  }

  /**

   * Writer that allows client to add marks to stream. These marks may become visible in log

   * console.

   */

  interface LoggableWriter {

    Writer getWriter();

    /**

     * Add log mark at current writer's position.

     */

    void markSeparatorForLog();

  }

}