/* This file is part of the KDE project
   Copyright (C) 2002 Anders Lund <anders.lund@lund.tdcadsl.dk>

   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License version 2 as published by the Free Software Foundation.

   This library 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
   Library General Public License for more details.

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


#include "kactionselector.h"

#include <klocale.h>
#include <kicon.h>
#include <kdebug.h>
#include <QtGui/QApplication>
#include <QtGui/QToolButton>
#include <QtGui/QLabel>
#include <QtGui/QLayout>
#include <QtGui/qevent.h>
#include <QListWidget>

class KActionSelectorPrivate {
  public:
  KActionSelectorPrivate(KActionSelector *q): q(q) {}
  
  KActionSelector *q;
  QListWidget *availableListWidget, *selectedListWidget;
  QToolButton *btnAdd, *btnRemove, *btnUp, *btnDown;
  QLabel *lAvailable, *lSelected;
  bool moveOnDoubleClick : 1;
  bool keyboardEnabled : 1;
  bool showUpDownButtons : 1;
  QString addIcon, removeIcon, upIcon, downIcon;
  KActionSelector::InsertionPolicy availableInsertionPolicy, selectedInsertionPolicy;

  /**
    Move item @p item to the other listbox
   */
  void moveItem( QListWidgetItem *item );
  
  /**
    loads the icons for the move buttons.
   */
  void loadIcons();
  
  /**
    @return the index to insert an item into listbox @p lb,
   given InsertionPolicy @p policy.
   
   Note that if policy is Sorted, this will return -1.
   Sort the listbox after inserting the item in that case.
   */
  int insertionIndex( QListWidget *lb, KActionSelector::InsertionPolicy policy );
  
  /**
   @return the index of the first selected item in listbox @p lb.
   If no item is selected, it will return -1.
   */
  int selectedRowIndex( QListWidget *lb );

  void buttonAddClicked();    
  void buttonRemoveClicked();
  void buttonUpClicked();
  void buttonDownClicked();
  void itemDoubleClicked( QListWidgetItem *item );
  void slotCurrentChanged( QListWidgetItem * )
  { q->setButtonsEnabled(); }
};

//BEGIN Constructor/destructor

KActionSelector::KActionSelector( QWidget *parent )
  : QWidget( parent )
  , d( new KActionSelectorPrivate(this) )
{
  d->moveOnDoubleClick = true;
  d->keyboardEnabled = true;
  d->addIcon = QApplication::isRightToLeft()? "go-previous" : "go-next";
  d->removeIcon = QApplication::isRightToLeft()? "go-next" : "go-previous";
  d->upIcon = "go-up";
  d->downIcon = "go-down";
  d->availableInsertionPolicy = Sorted;
  d->selectedInsertionPolicy = BelowCurrent;
  d->showUpDownButtons = true;

  QHBoxLayout *lo = new QHBoxLayout( this );
  lo->setMargin( 0 );

  QVBoxLayout *loAv = new QVBoxLayout();
  lo->addLayout( loAv );
  d->lAvailable = new QLabel( i18n("&Available:"), this );
  loAv->addWidget( d->lAvailable );
  d->availableListWidget = new QListWidget( this );
  loAv->addWidget( d->availableListWidget );
  d->lAvailable->setBuddy( d->availableListWidget );

  QVBoxLayout *loHBtns = new QVBoxLayout();
  lo->addLayout( loHBtns );
  loHBtns->addStretch( 1 );
  d->btnAdd = new QToolButton( this );
  loHBtns->addWidget( d->btnAdd );
  d->btnRemove = new QToolButton( this );
  loHBtns->addWidget( d->btnRemove );
  loHBtns->addStretch( 1 );

  QVBoxLayout *loS = new QVBoxLayout();
  lo->addLayout( loS );
  d->lSelected = new QLabel( i18n("&Selected:"), this );
  loS->addWidget( d->lSelected );
  d->selectedListWidget = new QListWidget( this );
  loS->addWidget( d->selectedListWidget );
  d->lSelected->setBuddy( d->selectedListWidget );

  QVBoxLayout *loVBtns = new QVBoxLayout();
  lo->addLayout( loVBtns );
  loVBtns->addStretch( 1 );
  d->btnUp = new QToolButton( this );
  d->btnUp->setAutoRepeat( true );
  loVBtns->addWidget( d->btnUp );
  d->btnDown = new QToolButton( this );
  d->btnDown->setAutoRepeat( true );
  loVBtns->addWidget( d->btnDown );
  loVBtns->addStretch( 1 );

  d->loadIcons();

  connect( d->btnAdd, SIGNAL(clicked()), this, SLOT(buttonAddClicked()) );
  connect( d->btnRemove, SIGNAL(clicked()), this, SLOT(buttonRemoveClicked()) );
  connect( d->btnUp, SIGNAL(clicked()), this, SLOT(buttonUpClicked()) );
  connect( d->btnDown, SIGNAL(clicked()), this, SLOT(buttonDownClicked()) );
  connect( d->availableListWidget, SIGNAL(itemDoubleClicked(QListWidgetItem*)),
           this, SLOT(itemDoubleClicked(QListWidgetItem*)) );
  connect( d->selectedListWidget, SIGNAL(itemDoubleClicked(QListWidgetItem*)),
           this, SLOT(itemDoubleClicked(QListWidgetItem*)) );
  connect( d->availableListWidget, SIGNAL(itemSelectionChanged()), this, SLOT(polish()) );
  connect( d->selectedListWidget, SIGNAL(itemSelectionChanged()), this, SLOT(polish()) );

  d->availableListWidget->installEventFilter( this );
  d->selectedListWidget->installEventFilter( this );
  setButtonsEnabled();
}

KActionSelector::~KActionSelector()
{
  delete d;
}

//END Constructor/destroctor

//BEGIN Public Methods

QListWidget *KActionSelector::availableListWidget() const
{
  return d->availableListWidget;
}

QListWidget *KActionSelector::selectedListWidget() const
{
  return d->selectedListWidget;
}

void KActionSelector::setButtonIcon( const QString &icon, MoveButton button )
{
  switch ( button )
  {
    case ButtonAdd:
      d->addIcon = icon;
      d->btnAdd->setIcon( KIcon( icon ) );
      break;
    case ButtonRemove:
      d->removeIcon = icon;
      d->btnRemove->setIcon( KIcon( icon ) );
      break;
    case ButtonUp:
      d->upIcon = icon;
      d->btnUp->setIcon( KIcon( icon ) );
      break;
    case ButtonDown:
      d->downIcon = icon;
      d->btnDown->setIcon( KIcon( icon ) );
      break;
    default:
      kDebug() << "DAINBREAD!";
      break;
  }
}

void KActionSelector::setButtonIconSet( const QIcon &iconset, MoveButton button )
{
  switch ( button )
  {
    case ButtonAdd:
      d->btnAdd->setIcon( iconset );
      break;
    case ButtonRemove:
      d->btnRemove->setIcon( iconset );
      break;
    case ButtonUp:
      d->btnUp->setIcon( iconset );
      break;
    case ButtonDown:
      d->btnDown->setIcon( iconset );
      break;
    default:
      kDebug() << "DAINBREAD!";
      break;
  }
}

void KActionSelector::setButtonTooltip( const QString &tip, MoveButton button )
{
  switch ( button )
  {
    case ButtonAdd:
      d->btnAdd->setText( tip );
      d->btnAdd->setToolTip( tip );
      break;
    case ButtonRemove:
      d->btnRemove->setText( tip );
      d->btnRemove->setToolTip( tip );
      break;
    case ButtonUp:
      d->btnUp->setText( tip );
      d->btnUp->setToolTip( tip );
      break;
    case ButtonDown:
      d->btnDown->setText( tip );
      d->btnDown->setToolTip( tip );
      break;
    default:
      kDebug() << "DAINBREAD!";
      break;
  }
}

void KActionSelector::setButtonWhatsThis( const QString &text, MoveButton button )
{
  switch ( button )
  {
    case ButtonAdd:
      d->btnAdd->setWhatsThis(text );
      break;
    case ButtonRemove:
      d->btnRemove->setWhatsThis(text );
      break;
    case ButtonUp:
      d->btnUp->setWhatsThis(text );
      break;
    case ButtonDown:
      d->btnDown->setWhatsThis(text );
      break;
    default:
      kDebug() << "DAINBREAD!";
      break;
  }
}

void KActionSelector::setButtonsEnabled()
{
  d->btnAdd->setEnabled( d->selectedRowIndex(d->availableListWidget) > -1 );
  d->btnRemove->setEnabled( d->selectedRowIndex(d->selectedListWidget) > -1 );
  d->btnUp->setEnabled( d->selectedRowIndex(d->selectedListWidget) > 0 );
  d->btnDown->setEnabled( d->selectedRowIndex(d->selectedListWidget) > -1 &&
                          d->selectedRowIndex(d->selectedListWidget) < d->selectedListWidget->count() - 1 );
}

//END Public Methods

//BEGIN Properties

bool KActionSelector::moveOnDoubleClick() const
{
  return d->moveOnDoubleClick;
}

void KActionSelector::setMoveOnDoubleClick( bool b )
{
  d->moveOnDoubleClick = b;
}

bool KActionSelector::keyboardEnabled() const
{
  return d->keyboardEnabled;
}

void KActionSelector::setKeyboardEnabled( bool b )
{
  d->keyboardEnabled = b;
}

QString KActionSelector::availableLabel() const
{
  return d->lAvailable->text();
}

void KActionSelector::setAvailableLabel( const QString &text )
{
  d->lAvailable->setText( text );
}

QString KActionSelector::selectedLabel() const
{
  return d->lSelected->text();
}

void KActionSelector::setSelectedLabel( const QString &text )
{
  d->lSelected->setText( text );
}

KActionSelector::InsertionPolicy KActionSelector::availableInsertionPolicy() const
{
  return d->availableInsertionPolicy;
}

void KActionSelector::setAvailableInsertionPolicy( InsertionPolicy p )
{
  d->availableInsertionPolicy = p;
}

KActionSelector::InsertionPolicy KActionSelector::selectedInsertionPolicy() const
{
  return d->selectedInsertionPolicy;
}

void KActionSelector::setSelectedInsertionPolicy( InsertionPolicy p )
{
  d->selectedInsertionPolicy = p;
}

bool KActionSelector::showUpDownButtons() const
{
  return d->showUpDownButtons;
}

void KActionSelector::setShowUpDownButtons( bool show )
{
  d->showUpDownButtons = show;
  if ( show )
  {
    d->btnUp->show();
    d->btnDown->show();
  }
  else
  {
    d->btnUp->hide();
    d->btnDown->hide();
  }
}

//END Properties

//BEGIN Public Slots

void KActionSelector::polish()
{
  setButtonsEnabled();
}

//END Public Slots

//BEGIN Protected
void KActionSelector::keyPressEvent( QKeyEvent *e )
{
  if ( ! d->keyboardEnabled ) return;
  if ( (e->modifiers() & Qt::ControlModifier) )
  {
    switch ( e->key() )
    {
      case Qt::Key_Right:
        d->buttonAddClicked();
        break;
      case Qt::Key_Left:
        d->buttonRemoveClicked();
        break;
      case Qt::Key_Up:
        d->buttonUpClicked();
        break;
      case Qt::Key_Down:
        d->buttonDownClicked();
        break;
      default:
        e->ignore();
        return;
    }
  }
}

bool KActionSelector::eventFilter( QObject *o, QEvent *e )
{
  if ( d->keyboardEnabled && e->type() == QEvent::KeyPress )
  {
    if  ( (((QKeyEvent*)e)->modifiers() & Qt::ControlModifier) )
    {
      switch ( ((QKeyEvent*)e)->key() )
      {
        case Qt::Key_Right:
          d->buttonAddClicked();
          break;
        case Qt::Key_Left:
          d->buttonRemoveClicked();
          break;
        case Qt::Key_Up:
          d->buttonUpClicked();
          break;
        case Qt::Key_Down:
          d->buttonDownClicked();
          break;
        default:
          return QWidget::eventFilter( o, e );
      }
      return true;
    }
    else if ( QListWidget *lb = qobject_cast<QListWidget*>(o) )
    {
      switch ( ((QKeyEvent*)e)->key() )
      {
        case Qt::Key_Return:
        case Qt::Key_Enter:
          int index = lb->currentRow();
          if ( index < 0 ) break;
          d->moveItem( lb->item( index ) );
          return true;
      }
    }
  }
  return QWidget::eventFilter( o, e );
}

//END Protected

//BEGIN Private Slots

void KActionSelectorPrivate::buttonAddClicked()
{
  // move all selected items from available to selected listbox
  QList<QListWidgetItem *> list = availableListWidget->selectedItems();
  foreach (QListWidgetItem* item, list) {
    availableListWidget->takeItem( availableListWidget->row( item ) );
    selectedListWidget->insertItem( insertionIndex( selectedListWidget, selectedInsertionPolicy ), item );
    selectedListWidget->setCurrentItem( item );
    emit q->added( item );
  }
  if ( selectedInsertionPolicy == KActionSelector::Sorted )
    selectedListWidget->sortItems();
  selectedListWidget->setFocus();
}

void KActionSelectorPrivate::buttonRemoveClicked()
{
  // move all selected items from selected to available listbox
  QList<QListWidgetItem *> list = selectedListWidget->selectedItems();
  foreach (QListWidgetItem* item, list) {
    selectedListWidget->takeItem( selectedListWidget->row( item ) );
    availableListWidget->insertItem( insertionIndex( availableListWidget, availableInsertionPolicy ), item );
    availableListWidget->setCurrentItem( item );
    emit q->removed( item );
  }
  if ( availableInsertionPolicy == KActionSelector::Sorted )
    availableListWidget->sortItems();
  availableListWidget->setFocus();
}

void KActionSelectorPrivate::buttonUpClicked()
{
  int c = selectedRowIndex(selectedListWidget);
  if ( c < 1 ) return;
  QListWidgetItem *item = selectedListWidget->item( c );
  selectedListWidget->takeItem( c );
  selectedListWidget->insertItem( c-1, item );
  selectedListWidget->setCurrentItem( item );
  emit q->movedUp( item );
}

void KActionSelectorPrivate::buttonDownClicked()
{
  int c = selectedRowIndex(selectedListWidget);
  if ( c < 0 || c == selectedListWidget->count() - 1 ) return;
  QListWidgetItem *item = selectedListWidget->item( c );
  selectedListWidget->takeItem( c );
  selectedListWidget->insertItem( c+1, item );
  selectedListWidget->setCurrentItem( item );
  emit q->movedDown( item );
}

void KActionSelectorPrivate::itemDoubleClicked( QListWidgetItem *item )
{
  if ( moveOnDoubleClick )
    moveItem( item );
}

//END Private Slots

//BEGIN Private Methods

void KActionSelectorPrivate::loadIcons()
{
  btnAdd->setIcon( KIcon( addIcon ) );
  btnRemove->setIcon( KIcon( removeIcon ) );
  btnUp->setIcon( KIcon( upIcon ) );
  btnDown->setIcon( KIcon( downIcon ) );
}

void KActionSelectorPrivate::moveItem( QListWidgetItem *item )
{
  QListWidget *lbFrom = item->listWidget();
  QListWidget *lbTo;
  if ( lbFrom == availableListWidget )
    lbTo = selectedListWidget;
  else if ( lbFrom == selectedListWidget )
    lbTo = availableListWidget;
  else  //?! somewhat unlikely...
    return;

  KActionSelector::InsertionPolicy p = ( lbTo == availableListWidget ) ?
                        availableInsertionPolicy : selectedInsertionPolicy;

  lbFrom->takeItem( lbFrom->row( item ) );
  lbTo->insertItem( insertionIndex( lbTo, p ), item );
  lbTo->setFocus();
  lbTo->setCurrentItem( item );

  if ( p == KActionSelector::Sorted )
    lbTo->sortItems();
  if ( lbTo == selectedListWidget )
    emit q->added( item );
  else
    emit q->removed( item );
}

int KActionSelectorPrivate::insertionIndex( QListWidget *lb, KActionSelector::InsertionPolicy policy )
{
  int index;
  switch ( policy )
  {
    case KActionSelector::BelowCurrent:
      index = lb->currentRow();
      if ( index > -1 ) index += 1;
      break;
    case KActionSelector::AtTop:
      index = 0;
      break;
    default:
      index = -1;
      break;
  }
  return index;
}

int KActionSelectorPrivate::selectedRowIndex( QListWidget *lb )
{
  QList<QListWidgetItem *> list = lb->selectedItems();
  if (list.isEmpty()) {
    return -1;
  }
  return lb->row(list.at(0));
}

//END Private Methods
#include "moc_kactionselector.cpp"