/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   ### File Specific:
   main-programmer: Benjamin Grauer
   co-programmer: ...
*/

//#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_

#include "shell_buffer.h"
#include "debug.h"
#include "shell.h"

#include "stdlibincl.h"

using namespace std;


/**
 * @brief standard constructor
 */
ShellBuffer::ShellBuffer ()
{
  ShellBuffer::singletonRef = this;
  this->shell = NULL;

  this->lineCount = 0;
  this->keepBufferArray[0] = '\0';
  this->bufferArray[0] = '\0';
  this->keepBuffer = false;

  this->setBufferSize(100);
}

ShellBuffer* ShellBuffer::singletonRef = NULL;
SDL_mutex* ShellBuffer::bufferMutex = NULL;

/**
 * @brief standard deconstructor
 */
ShellBuffer::~ShellBuffer ()
{
  if (this->shell != NULL)
    delete this->shell;

  this->flush();

  if (ShellBuffer::bufferMutex != NULL)
    SDL_DestroyMutex(ShellBuffer::bufferMutex);
  ShellBuffer::bufferMutex = NULL;

  ShellBuffer::singletonRef = NULL;
}

/**
 * @brief registers the Shell to the Buffer
 * @param shell the Shell to register.
 */
void ShellBuffer::registerShell(Shell* shell)
{
  if (this->shell == NULL)
    this->shell = shell;
  else
    PRINTF(1)("already registered a Shell to the ShellBuffer\n");
}

/**
 * @brief unregisters the Shell from the Buffer
 * @param shell the Shell to unregister.
 */
void ShellBuffer::unregisterShell(Shell* shell)
{
  if (this->shell == shell)
    this->shell = NULL;
  else
    PRINTF(1)("cannot unregister shell, because it is not registered to the ShellBuffer\n");
}

/**
 * @brief deletes all the Buffers
 */
void ShellBuffer::flush()
{
  this->buffer.clear();
}

/**
 * @brief adds a new Line to the List of Buffers
 * @param line the Line as in the first argument in printf
 */
bool ShellBuffer::addBufferLineStatic(const char* line, ...)
{
  va_list arguments;
  va_start(arguments, line);

  if (ShellBuffer::bufferMutex == NULL)
    ShellBuffer::bufferMutex = SDL_CreateMutex();

  SDL_mutexP(ShellBuffer::bufferMutex);
#if DEBUG < 3
  if (ShellBuffer::singletonRef == NULL)
#endif
    vprintf(line, arguments);
#if DEBUG < 3
  else
#else
  if (ShellBuffer::singletonRef != NULL)
#endif
    ShellBuffer::singletonRef->addBufferLine(line, arguments);
  SDL_mutexV(ShellBuffer::bufferMutex);
  return true;
}

/**
 * @brief add a Line to the List of Buffers
 * @param line
 * @param arguments
 *
 * This function Adds one line to the buffer.
 * and displays the line as the First Line of the display-buffer
 */
void ShellBuffer::addBufferLine(const char* line, va_list arguments)
{
  char* inputEnd;
  char* newLineBegin;
  char* newLineEnd;

  // copy the output to the bufferArray
  vsprintf(this->bufferArray, line, arguments);

  // check if we have something left in the buffers
  // if so, append the new String to this one.
  if (unlikely(this->keepBuffer))
  {
    strcat(this->keepBufferArray, this->bufferArray);
    inputEnd = this->keepBufferArray + strlen(this->bufferArray);
    newLineBegin = this->keepBufferArray;
    this->keepBuffer = false;
  }
  else
  {
    inputEnd = this->bufferArray + strlen(this->bufferArray);
    newLineBegin = this->bufferArray;
  }

  // adding all the new Lines
  while (newLineBegin < inputEnd)
  {
    newLineEnd = strchr(newLineBegin, '\n');
    if (likely(newLineEnd != NULL && *newLineEnd == '\n'))
      *newLineEnd = '\0';
    else
    {
      unsigned int len = strlen(newLineBegin);
      char* copyBuffer = new char[len+1];
      strcpy(copyBuffer, newLineBegin);
      strncpy(this->keepBufferArray, copyBuffer, len);
      delete[] copyBuffer;
      this->keepBufferArray[len] = '\0';
      this->keepBuffer = true;
      break;
    }

    this->lineCount++;
    this->buffer.push_back(newLineBegin);
    if (likely (this->shell != NULL) && unlikely (this->shell->isActive()))
      this->shell->printToDisplayBuffer(newLineBegin);

    if (this->buffer.size() > this->bufferSize)
      this->buffer.pop_front();

    newLineBegin = newLineEnd+1;
  }
}

/**
 * displays some nice output from the Shell
 */
void ShellBuffer::debug() const
{
  PRINT(3)("Debugging output to console (not this shell)\n");

  list<std::string>::const_iterator bufferLine;
  for (bufferLine = this->buffer.begin(); bufferLine != this->buffer.end(); bufferLine++)
    printf((*bufferLine).c_str());
}