/*

 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#ifndef SHARE_VM_LOGGING_LOGMESSAGEBUFFER_HPP

#define SHARE_VM_LOGGING_LOGMESSAGEBUFFER_HPP

#include "logging/logDecorations.hpp"

#include "logging/logLevel.hpp"

#include "memory/allocation.hpp"

class LogMessageBuffer : public StackObj {

  friend class LogMessageTest;

 protected:

  struct LogLine VALUE_OBJ_CLASS_SPEC {

    LogLevelType level;

    size_t message_offset;

  };

  static const size_t InitialLineCapacity = 10;

  static const size_t InitialMessageBufferCapacity = 1024;

  size_t _message_buffer_size;

  size_t _message_buffer_capacity;

  char* _message_buffer;

  size_t _line_count;

  size_t _line_capacity;

  LogLine* _lines;

  bool _allocated;

  LogLevelType _least_detailed_level;

  size_t (*_prefix_fn)(char*, size_t);

  void initialize_buffers();

 private:

  // Forbid copy assignment and copy constructor.

  void operator=(const LogMessageBuffer& ref) {}

  LogMessageBuffer(const LogMessageBuffer& ref) {}

 public:

  LogMessageBuffer();

  ~LogMessageBuffer();

  class Iterator {

   private:

    const LogMessageBuffer& _message;

    size_t _current_line_index;

    LogLevelType _level;

    LogDecorations &_decorations;

    void skip_messages_with_finer_level();

   public:

    Iterator(const LogMessageBuffer& message, LogLevelType level, LogDecorations& decorations)

        : _message(message), _level(level), _decorations(decorations), _current_line_index(0) {

      skip_messages_with_finer_level();

    }

    void operator++(int) {

      _current_line_index++;

      skip_messages_with_finer_level();

    }

    bool is_at_end() {

      return _current_line_index == _message._line_count;

    }

    const char* message() const {

      return _message._message_buffer + _message._lines[_current_line_index].message_offset;

    }

    const LogDecorations& decorations() {

      _decorations.set_level(_message._lines[_current_line_index].level);

      return _decorations;

    }

  };

  void reset();

  LogLevelType least_detailed_level() const {

    return _least_detailed_level;

  }

  Iterator iterator(LogLevelType level, LogDecorations& decorations) const {

    return Iterator(*this, level, decorations);

  }

  // Lines in LogMessageBuffers are not automatically prefixed based on tags

  // like regular simple messages (see LogPrefix.hpp for more about prefixes).

  // It is, however, possible to specify a prefix per LogMessageBuffer,

  // using set_prefix(). Lines added to the LogMessageBuffer after a prefix

  // function has been set will be prefixed automatically.

  // Setting this to NULL will disable prefixing.

  void set_prefix(size_t (*prefix_fn)(char*, size_t)) {

    _prefix_fn = prefix_fn;

  }

  ATTRIBUTE_PRINTF(3, 4)

  void write(LogLevelType level, const char* fmt, ...);

  ATTRIBUTE_PRINTF(3, 0)

  virtual void vwrite(LogLevelType level, const char* fmt, va_list args);

#define LOG_LEVEL(level, name) \

  LogMessageBuffer& v##name(const char* fmt, va_list args) ATTRIBUTE_PRINTF(2, 0); \

  LogMessageBuffer& name(const char* fmt, ...) ATTRIBUTE_PRINTF(2, 3);

  LOG_LEVEL_LIST

#undef LOG_LEVEL

};

#endif // SHARE_VM_LOGGING_LOGMESSAGEBUFFER_HPP