/*
   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_SHELL

#include "shell_input.h"

#include "shell_command.h"
#include "shell_command_class.h"

#include "debug.h"
#include "compiler.h"
#include "key_names.h"

#include "game_world.h"
#include "state.h"


namespace OrxShell
{
  ObjectListDefinition(ShellInput);

  /**
   * @brief constructor
   * this also generates a ShellCompletion automatically.
  */
  ShellInput::ShellInput ()
      : Text ("")
  {
    this->registerObject(this, ShellInput::_objectList);

    this->pressedKey = SDLK_FIRST;

    this->historyIT = ShellInput::history.begin();
    this->setHistoryLength(50);
    this->historyScrolling = false;
    this->delayed = 0;
    this->setRepeatDelay(.3, .05);

    // subscribe all keyboard commands to ES_SHELL
    for (int i = 1; i < SDLK_LAST; i++)
    {
      //if (!this->isEventSubscribed(ES_SHELL, i))
      this->subscribeEvent(ES_SHELL, i);
    }
    // unsubscribe unused TODO improve.
    this->unsubscribeEvent(ES_SHELL, SDLK_BACKQUOTE);
    this->unsubscribeEvent(ES_SHELL, SDLK_F12);
    this->unsubscribeEvent(ES_SHELL, SDLK_PAGEUP);
    this->unsubscribeEvent(ES_SHELL, SDLK_PAGEDOWN);
  }

  std::list<std::string> ShellInput::history;

  /**
   * @brief standard deconstructor
   */
  ShellInput::~ShellInput ()
  {}

  /**
   * @brief sets the Repeate-delay and rate
   * @param repeatDelay the Delay it takes, to repeate a key
   * @param repeatRate the rate to repeate a pressed key
   */
  void ShellInput::setRepeatDelay(float repeatDelay, float repeatRate)
  {
    this->repeatDelay = repeatDelay;
    this->repeatRate = repeatRate;
  }

  /**
   * @brief deletes the InputLine
   */
  void ShellInput::flush()
  {
    this->inputLineBegin.clear();
    this->inputLineEnd.clear();
    this->clear();
  }

  /**
   * @brief sets the entire text of the InputLine to text
   * @param text the new Text to set as InputLine
   */
  void ShellInput::setInputText(const std::string& text)
  {
    this->inputLineBegin = text;
    this->inputLineEnd.clear();
    this->setText(text);
  }


  /**
   * @brief adds one character to the inputLine
   * @param character the character to add to the inputLine
   */
  void ShellInput::addCharacter(char character)
  {
    if (this->historyScrolling)
    {
      this->history.pop_back();
      this->historyScrolling = false;
    }

    this->inputLineBegin += character;
    this->setText(this->inputLineBegin + this->inputLineEnd);
  }

  /**
   * @brief adds multiple Characters to thr inputLine
   * @param characters a \\0 terminated char-array to add to the InputLine
   */
  void ShellInput::addCharacters(const std::string& characters)
  {
    if (this->historyScrolling)
    {
      this->history.pop_back();
      this->historyScrolling = false;
    }

    this->inputLineBegin += characters;
    this->setText(this->inputLineBegin + this->inputLineEnd);
  }

  /**
   * @brief removes characterCount characters from the InputLine
   * @param characterCount the count of Characters to remove from the input Line
   */
  void ShellInput::removeCharacters(unsigned int characterCount)
  {
    if (this->historyScrolling)
    {
      this->history.pop_back();
      this->historyScrolling = false;
    }
    if (this->inputLineBegin.size() < characterCount)
      characterCount = this->inputLineBegin.size();

    this->inputLineBegin.erase(this->inputLineBegin.size() - characterCount, this->inputLineBegin.size());
    this->setText(this->inputLineBegin + this->inputLineEnd);
  }

  /**
   * @brief executes the command stored in the inputLine
   * @return true if the command was commited successfully, false otherwise
   */
  bool ShellInput::executeCommand()
  {
    if (this->getInput().empty())
      return false;
    DebugBuffer::addBufferLineStatic("Execute Command: %s\n", this->getInput().c_str());

    ShellCommand::execute(this->getInput());

    // removing the eventually added Entry (from scrolling) to the List
    if (this->historyScrolling)
    {
      this->history.pop_back();
      this->historyScrolling = false;
    }

    // adding the new Command to the History
    if (history.empty() || history.back() != this->getInput())
      this->history.push_back(this->getInput());
    if (this->history.size() > this->historyLength)
    {
      this->history.pop_front();
    }

    this->flush();

    return true;
  }


  /**
   * @brief moves one entry up in the history.
   */
  void ShellInput::historyMoveUp()
  {
    if (!this->historyScrolling)
    {
      this->history.push_back(this->getInput());
      this->historyScrolling = true;
      this->historyIT = --this->history.end();
    }

    if(this->historyIT != this->history.begin())
    {
      std::string prevElem = *(--this->historyIT);
      /*if (prevElem == NULL) /// TODO STD
        return;
      else */
      {
        this->flush();
        this->setInputText(prevElem);
      }
    }
  }

  /**
   * @brief moves one entry down in the history
   */
  void ShellInput::historyMoveDown()
  {
    if (!this->historyScrolling)
      return;
    if (!this->history.empty() && this->historyIT != --this->history.end())
    {
      std::string nextElem = *(++this->historyIT);
      /*    if (nextElem == NULL) /// TODO FIX STD
        return;
      else */
      {
        this->flush();
        this->setInputText(nextElem);
      }
    }
  }

  /**
   * @brief moves the cursor chars Characters to the right.
   * @param chars how much to move the cursor.
   */
  void ShellInput::moveCursor(int chars)
  {
    if (chars > 0)
    {
      PRINTF(5)("move cursor %d to the right\n", chars);
      if (chars >= (int) this->inputLineEnd.size())
        chars = inputLineEnd.size();
      this->inputLineBegin += this->inputLineEnd.substr(0, chars);
      this->inputLineEnd.erase(0, chars);
    }
    else if (chars < 0)
    {
      chars = -chars;
      PRINTF(5)("move cursor %d to the left\n", chars);

      if (chars >= (int) this->inputLineBegin.size())
	chars = inputLineBegin.size();
      this->inputLineEnd = this->inputLineBegin.substr(this->inputLineBegin.size() - chars) + this->inputLineEnd;
      this->inputLineBegin.erase(this->inputLineBegin.size() - chars);
    }
  }


  /**
   * @brief prints out some nice help about the Shell
   */
  void ShellInput::help(const std::string& className, const std::string& functionName)
  {
    if (className.empty())
    {
      PRINT(0)("== Help for the most important Shell-commands\n");
      PRINT(0)("  F1 - HELP; F2 - DEBUG; '`' - open/close shell\n");
      PRINT(0)("  input order:\n");
      PRINT(0)("   ClassName [objectName] function [parameter1, [parameter2 ...]]  or\n");
      PRINT(0)("   Alias [parameter]\n");
      PRINT(0)("- Also try 'help className' or pushing 'TAB'\n");
    }
    else if (!className.empty() && functionName.empty())
    {
      ShellCommandClass::help(className);
      //PRINTF(1)("%s::%s\n", className, functionName);
    }
  }

  /**
   * @brief ticks the ShellInput
   * @param dt the time passed since the last update
   */
  void ShellInput::tick(float dt)
  {
    if (this->delayed > 0.0)
    {
      StoryEntity* storyEntity = State::getCurrentStoryEntity();
      float speed = 1;
      if ( storyEntity && storyEntity->isA( GameWorld::staticClassID() ) )
      {
        speed = ((GameWorld*)storyEntity)->getSpeed();
      }
      this->delayed -= dt / speed;
    }
    else if (this->pressedKey != SDLK_FIRST )
    {
      this->delayed = this->repeatRate;
      switch (this->pressedKey )
      {
        case SDLK_BACKSPACE:
        this->removeCharacters(1);
        break;
        case SDLK_UP:
        this->historyMoveUp();
        break;
        case SDLK_DOWN:
        this->historyMoveDown();
        break;
        default:
        {
          if (likely(pressedKey < 127))
            this->addCharacter(this->pressedKey);
        }
      }
    }
  }

  /**
   * @brief listens for some event
   * @param event the Event happened
   */
  void ShellInput::process(const Event &event)
  {
    if (event.bPressed)
    {
      PRINTF(5)("Shell received command %s\n", SDLKToKeyname(event.type).c_str());
      if (event.type == SDLK_F1)
        this->help();
      else if (event.type == SDLK_F2)
      {
        ;//this->debug();
      }
      else if (event.type == SDLK_UP)
      {
        this->historyMoveUp();
        this->pressedKey = event.type;
        this->pressedEvent = event.type;
      }
      else if (event.type == SDLK_DOWN)
      {
        this->historyMoveDown();
        this->pressedKey = event.type;
        this->pressedEvent = event.type;
      }
      else if (event.type == SDLK_LEFT)
      {
        this->moveCursor(-1);
        this->pressedKey = event.type;
        this->pressedEvent = event.type;
      }
      else if (event.type == SDLK_RIGHT)
      {
        this->moveCursor(+1);
        this->pressedKey = event.type;
        this->pressedEvent = event.type;
      }
      else if (event.type == SDLK_TAB)
      {
        this->completion.autoComplete(this->inputLineBegin);
        this->setText(this->getInput());
      }
      else if (event.type == SDLK_BACKSPACE)
      {
        this->delayed = this->repeatDelay;
        this->pressedKey = SDLK_BACKSPACE;
        this->pressedEvent = SDLK_BACKSPACE;
        this->removeCharacters(1);
      }
      else if (event.type == SDLK_DELETE)
      {
	if (!this->inputLineEnd.empty())
	{
	  this->inputLineEnd.erase(0, 1);
	  this->setText(this->getInput());
	}
      }
      else if (event.type == SDLK_RETURN)
      {
        this->executeCommand();
        this->pressedKey = event.type;
        this->pressedEvent = event.type;
      }
      // any other keyboard key
      else if (likely(event.type < 127))
      {
        this->addCharacter(event.x);
        this->pressedKey = event.x;
        this->pressedEvent = event.type;
      }
      this->delayed = this->repeatDelay;
    }
    else // if(!event.bPressed)
    {
      if (this->pressedEvent == event.type)
      {
        this->pressedEvent = 0;
        this->pressedKey = 0;
        this->delayed = 0.0;
      }
    }
  }

}