/*
    Copyright 2007-2008 Robert Knight <robertknight@gmail.com>
    Copyright 1997,1998 by Lars Doelle <lars.doelle@on-line.de>
    Copyright 1996 by Matthias Ettrich <ettrich@kde.org>

    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 of the License, or
    (at your option) any later version.

    This program 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 for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
    02110-1301  USA.
*/

// Own
#include "Emulation.h"

// Qt
#include <QtGui/QKeyEvent>

// Konsole
#include "KeyboardTranslator.h"
#include "KeyboardTranslatorManager.h"
#include "Screen.h"
#include "ScreenWindow.h"

using namespace Konsole;

Emulation::Emulation() :
    _currentScreen(0),
    _codec(0),
    _decoder(0),
    _keyTranslator(0),
    _usesMouse(false),
    _imageSizeInitialized(false)
{
    // create screens with a default size
    _screen[0] = new Screen(40, 80);
    _screen[1] = new Screen(40, 80);
    _currentScreen = _screen[0];

    QObject::connect(&_bulkTimer1, SIGNAL(timeout()), this, SLOT(showBulk()));
    QObject::connect(&_bulkTimer2, SIGNAL(timeout()), this, SLOT(showBulk()));

    // listen for mouse status changes
    connect(this , SIGNAL(programUsesMouseChanged(bool)) ,
            SLOT(usesMouseChanged(bool)));
}

bool Emulation::programUsesMouse() const
{
    return _usesMouse;
}

void Emulation::usesMouseChanged(bool usesMouse)
{
    _usesMouse = usesMouse;
}

ScreenWindow* Emulation::createWindow()
{
    ScreenWindow* window = new ScreenWindow();
    window->setScreen(_currentScreen);
    _windows << window;

    connect(window , SIGNAL(selectionChanged()),
            this , SLOT(bufferedUpdate()));
    connect(window, SIGNAL(selectionChanged()),
            this, SLOT(checkSelectedText()));

    connect(this , SIGNAL(outputChanged()),
            window , SLOT(notifyOutputChanged()));

    return window;
}

void Emulation::checkScreenInUse()
{
    emit primaryScreenInUse(_currentScreen == _screen[0]);
}

void Emulation::checkSelectedText()
{
    QString text = _currentScreen->selectedText(true);
    emit selectionChanged(text);
}

Emulation::~Emulation()
{
    foreach(ScreenWindow* window, _windows) {
        delete window;
    }

    delete _screen[0];
    delete _screen[1];
    delete _decoder;
}

void Emulation::setScreen(int index)
{
    Screen* oldScreen = _currentScreen;
    _currentScreen = _screen[index & 1];
    if (_currentScreen != oldScreen) {
        // tell all windows onto this emulation to switch to the newly active screen
        foreach(ScreenWindow * window, _windows) {
            window->setScreen(_currentScreen);
        }

        checkScreenInUse();
        checkSelectedText();
    }
}

void Emulation::clearHistory()
{
    _screen[0]->setScroll(_screen[0]->getScroll() , false);
}
void Emulation::setHistory(const HistoryType& history)
{
    _screen[0]->setScroll(history);

    showBulk();
}

const HistoryType& Emulation::history() const
{
    return _screen[0]->getScroll();
}

void Emulation::setCodec(const QTextCodec * codec)
{
    if (codec) {
        _codec = codec;

        delete _decoder;
        _decoder = _codec->makeDecoder();

        emit useUtf8Request(utf8());
    } else {
        setCodec(LocaleCodec);
    }
}

void Emulation::setCodec(EmulationCodec codec)
{
    if (codec == Utf8Codec)
        setCodec(QTextCodec::codecForName("utf8"));
    else if (codec == LocaleCodec)
        setCodec(QTextCodec::codecForLocale());
}

void Emulation::setKeyBindings(const QString& name)
{
    _keyTranslator = KeyboardTranslatorManager::instance()->findTranslator(name);
    if (!_keyTranslator) {
        _keyTranslator = KeyboardTranslatorManager::instance()->defaultTranslator();
    }
}

QString Emulation::keyBindings() const
{
    return _keyTranslator->name();
}

// process application unicode input to terminal
// this is a trivial scanner
void Emulation::receiveChar(int c)
{
    c &= 0xff;
    switch (c) {
    case '\b'      : _currentScreen->backspace();                 break;
    case '\t'      : _currentScreen->tab();                       break;
    case '\n'      : _currentScreen->newLine();                   break;
    case '\r'      : _currentScreen->toStartOfLine();             break;
    case 0x07      : emit stateSet(NOTIFYBELL);                   break;
    default        : _currentScreen->displayCharacter(c);         break;
    }
}

void Emulation::sendKeyEvent(QKeyEvent* ev)
{
    emit stateSet(NOTIFYNORMAL);

    if (!ev->text().isEmpty()) {
        // A block of text
        // Note that the text is proper unicode.
        // We should do a conversion here
        emit sendData(ev->text().toUtf8(), ev->text().length());
    }
}

void Emulation::sendString(const char*, int)
{
    // default implementation does nothing
}

void Emulation::sendMouseEvent(int /*buttons*/, int /*column*/, int /*row*/, int /*eventType*/)
{
    // default implementation does nothing
}

/*
   We are doing code conversion from locale to unicode first.
*/

void Emulation::receiveData(const char* text, int length)
{
    emit stateSet(NOTIFYACTIVITY);

    bufferedUpdate();

    QString unicodeText = _decoder->toUnicode(text, length);

    //send characters to terminal emulator
    for (int i = 0; i < unicodeText.length(); i++)
        receiveChar(unicodeText[i].unicode());

    //look for z-modem indicator
    //-- someone who understands more about z-modems that I do may be able to move
    //this check into the above for loop?
    for (int i = 0; i < length; i++) {
        if (text[i] == '\030') {
            if ((length - i - 1 > 3) && (qstrncmp(text + i + 1, "B00", 3) == 0))
                emit zmodemDetected();
        }
    }
}

//OLDER VERSION
//This version of onRcvBlock was commented out because
//    a)  It decoded incoming characters one-by-one, which is slow in the current version of Qt (4.2 tech preview)
//    b)  It messed up decoding of non-ASCII characters, with the result that (for example) chinese characters
//        were not printed properly.
//
//There is something about stopping the _decoder if "we get a control code halfway a multi-byte sequence" (see below)
//which hasn't been ported into the newer function (above).  Hopefully someone who understands this better
//can find an alternative way of handling the check.

/*void Emulation::onRcvBlock(const char *s, int len)
{
  emit notifySessionState(NOTIFYACTIVITY);

  bufferedUpdate();
  for (int i = 0; i < len; i++)
  {

    QString result = _decoder->toUnicode(&s[i],1);
    int reslen = result.length();

    // If we get a control code halfway a multi-byte sequence
    // we flush the _decoder and continue with the control code.
    if ((s[i] < 32) && (s[i] > 0))
    {
       // Flush _decoder
       while(!result.length())
          result = _decoder->toUnicode(&s[i],1);
       reslen = 1;
       result.resize(reslen);
       result[0] = QChar(s[i]);
    }

    for (int j = 0; j < reslen; j++)
    {
      if (result[j].characterategory() == QChar::Mark_NonSpacing)
         _currentScreen->compose(result.mid(j,1));
      else
         onRcvChar(result[j].unicode());
    }
    if (s[i] == '\030')
    {
      if ((len-i-1 > 3) && (qstrncmp(s+i+1, "B00", 3) == 0))
          emit zmodemDetected();
    }
  }
}*/

void Emulation::writeToStream(TerminalCharacterDecoder* decoder ,
                              int startLine ,
                              int endLine)
{
    _currentScreen->writeLinesToStream(decoder, startLine, endLine);
}

int Emulation::lineCount() const
{
    // sum number of lines currently on _screen plus number of lines in history
    return _currentScreen->getLines() + _currentScreen->getHistLines();
}

void Emulation::showBulk()
{
    _bulkTimer1.stop();
    _bulkTimer2.stop();

    emit outputChanged();

    _currentScreen->resetScrolledLines();
    _currentScreen->resetDroppedLines();
}

void Emulation::bufferedUpdate()
{
    static const int BULK_TIMEOUT1 = 10;
    static const int BULK_TIMEOUT2 = 40;

    _bulkTimer1.setSingleShot(true);
    _bulkTimer1.start(BULK_TIMEOUT1);
    if (!_bulkTimer2.isActive()) {
        _bulkTimer2.setSingleShot(true);
        _bulkTimer2.start(BULK_TIMEOUT2);
    }
}

char Emulation::eraseChar() const
{
    return '\b';
}

void Emulation::setImageSize(int lines, int columns)
{
    if ((lines < 1) || (columns < 1))
        return;

    QSize screenSize[2] = { QSize(_screen[0]->getColumns(),
                                  _screen[0]->getLines()),
                            QSize(_screen[1]->getColumns(),
                                  _screen[1]->getLines())
                          };
    QSize newSize(columns, lines);

    if (newSize == screenSize[0] && newSize == screenSize[1]) {
        // If this method is called for the first time, always emit
        // SIGNAL(imageSizeChange()), even if the new size is the same as the
        // current size.  See #176902
        if (!_imageSizeInitialized) {
            emit imageSizeChanged(lines, columns);
        }
    } else {
        _screen[0]->resizeImage(lines, columns);
        _screen[1]->resizeImage(lines, columns);

        emit imageSizeChanged(lines, columns);

        bufferedUpdate();
    }

    if (!_imageSizeInitialized) {
        _imageSizeInitialized = true;

        // FIXME
        // a hard-coded, small delay is introduced to guarantee Session::run()
        // does not get triggered by SIGNAL(imageSizeInitialized()) before
        // Pty::setWindowSize() is triggered by previously emitted
        // SIGNAL(imageSizeChanged()); See #203185
        QTimer::singleShot(200, this, SIGNAL(imageSizeInitialized()));
    }
}

QSize Emulation::imageSize() const
{
    return QSize(_currentScreen->getColumns(), _currentScreen->getLines());
}

#include "Emulation.moc"