runtime/khelpcenter/history.cpp

   1 /*
   2  *  This file is part of the KDE Help Center
   3  *
   4  *  Copyright (C) 2002 Frerich Raabe <raabe@kde.org>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19  */
  20 #include "history.h"
  21 #include "view.h"
  22 #include <QMenu>
  23 #include <kaction.h>
  24 #include <kactioncollection.h>
  25 #include <kapplication.h>
  26 #include <kdebug.h>
  27 #include <kicon.h>
  28 #include <kxmlguiwindow.h>
  29 #include <kmenu.h>
  30 #include <kstandardguiitem.h>
  31 #include <kstringhandler.h>
  32 #include <ktoolbarpopupaction.h>
  33 #include <kxmlguifactory.h>
  34
  35
  36 using namespace KHC;
  37
  38 History *History::m_instance = 0;
  39
  40 History &History::self()
  41 {
  42   if  ( !m_instance )
  43     m_instance = new History;
  44   return *m_instance;
  45 }
  46
  47 History::History() : QObject(),
  48   m_goBuffer( 0 )
  49 {
  50   m_entries.setAutoDelete( true );
  51 }
  52
  53 History::~History()
  54 {
  55 }
  56
  57 void History::setupActions( KActionCollection *coll )
  58 {
  59   QPair<KGuiItem, KGuiItem> backForward = KStandardGuiItem::backAndForward();
  60
  61   m_backAction = new KToolBarPopupAction( KIcon( backForward.first.iconName() ), backForward.first.text(), this );
  62   coll->addAction( "back", m_backAction );
  63   m_backAction->setShortcut( Qt::ALT+Qt::Key_Left );
  64   connect( m_backAction, SIGNAL( triggered() ), this, SLOT( back() ) );
  65
  66   connect( m_backAction->menu(), SIGNAL( activated( int ) ),
  67            SLOT( backActivated( int ) ) );
  68   connect( m_backAction->menu(), SIGNAL( aboutToShow() ),
  69            SLOT( fillBackMenu() ) );
  70   m_backAction->setEnabled( false );
  71
  72   m_forwardAction = new KToolBarPopupAction( KIcon( backForward.second.iconName() ), backForward.second.text(), this );
  73   coll->addAction( QLatin1String("forward"), m_forwardAction );
  74   m_forwardAction->setShortcut( Qt::ALT+Qt::Key_Right );
  75   connect( m_forwardAction, SIGNAL( triggered() ), this, SLOT( forward() ) );
  76
  77   connect( m_forwardAction->menu(), SIGNAL( activated( int ) ),
  78            SLOT( forwardActivated( int ) ) );
  79   connect( m_forwardAction->menu(), SIGNAL( aboutToShow() ),
  80            SLOT( fillForwardMenu() ) );
  81   m_forwardAction->setEnabled( false );
  82 }
  83 void History::installMenuBarHook( KXmlGuiWindow *mainWindow )
  84 {
  85   QMenu *goMenu = dynamic_cast<QMenu *>(
  86       mainWindow->guiFactory()->container( QLatin1String("go_web"), mainWindow ) );
  87   if ( goMenu ) {
  88     connect( goMenu, SIGNAL( aboutToShow() ), SLOT( fillGoMenu() ) );
  89     connect( goMenu, SIGNAL( activated( int ) ),
  90              SLOT( goMenuActivated( int ) ) );
  91     m_goMenuIndex = goMenu->actions().count();
  92   }
  93 }
  94
  95 void History::createEntry()
  96 {
  97   kDebug() << "History::createEntry()";
  98
  99   // First, remove any forward history
 100   Entry * current = m_entries.current();
 101   if (current)
 102   {
 103     m_entries.at( m_entries.count() - 1 ); // go to last one
 104     for ( ; m_entries.current() != current ; )
 105     {
 106       if ( !m_entries.removeLast() ) { // and remove from the end (faster and easier)
 107         Q_ASSERT(0);
 108         return;
 109       }
 110       else
 111         m_entries.at( m_entries.count() - 1 );
 112     }
 113     // Now current is the current again.
 114
 115     // If current entry is empty reuse it.
 116     if ( !current->view ) return;
 117   }
 118
 119   // Append a new entry
 120   m_entries.append( new Entry ); // made current
 121   Q_ASSERT( m_entries.at() == (int) m_entries.count() - 1 );
 122 }
 123
 124 void History::updateCurrentEntry( View *view )
 125 {
 126   if ( m_entries.isEmpty() )
 127     return;
 128
 129   KUrl url = view->url();
 130
 131   Entry *current = m_entries.current();
 132
 133   QDataStream stream( &current->buffer, QIODevice::WriteOnly );
 134   view->browserExtension()->saveState( stream );
 135
 136   current->view = view;
 137
 138   if ( url.isEmpty() ) {
 139     kDebug() << "History::updateCurrentEntry(): internal url";
 140     url = view->internalUrl();
 141   }
 142
 143   kDebug() << "History::updateCurrentEntry(): " << view->title()
 144             << " (URL: " << url.url() << ")" << endl;
 145
 146   current->url = url;
 147   current->title = view->title();
 148
 149   current->search = view->state() == View::Search;
 150 }
 151
 152 void History::updateActions()
 153 {
 154   m_backAction->setEnabled( canGoBack() );
 155   m_forwardAction->setEnabled( canGoForward() );
 156 }
 157
 158 void History::back()
 159 {
 160   kDebug( 1400 ) << "History::back()";
 161   goHistoryActivated( -1 );
 162 }
 163
 164 void History::backActivated( int id )
 165 {
 166   kDebug( 1400 ) << "History::backActivated(): id = " << id;
 167   goHistoryActivated( -( m_backAction->menu()->indexOf( id ) + 1 ) );
 168 }
 169
 170 void History::forward()
 171 {
 172   kDebug( 1400 ) << "History::forward()";
 173   goHistoryActivated( 1 );
 174 }
 175
 176 void History::forwardActivated( int id )
 177 {
 178   kDebug( 1400 ) << "History::forwardActivated(): id = " << id;
 179   goHistoryActivated( m_forwardAction->menu()->indexOf( id ) + 1 );
 180 }
 181
 182 void History::goHistoryActivated( int steps )
 183 {
 184   kDebug( 1400 ) << "History::goHistoryActivated(): m_goBuffer = " << m_goBuffer;
 185   if ( m_goBuffer )
 186     return;
 187   m_goBuffer = steps;
 188   QTimer::singleShot( 0, this, SLOT( goHistoryDelayed() ) );
 189 }
 190
 191 void History::goHistoryDelayed()
 192 {
 193   kDebug( 1400 ) << "History::goHistoryDelayed(): m_goBuffer = " << m_goBuffer;
 194   if ( !m_goBuffer )
 195     return;
 196   int steps = m_goBuffer;
 197   m_goBuffer = 0;
 198   goHistory( steps );
 199 }
 200
 201 void History::goHistory( int steps )
 202 {
 203   kDebug() << "History::goHistory(): " << steps;
 204
 205   // If current entry is empty remove it.
 206   Entry *current = m_entries.current();
 207   if ( current && !current->view ) m_entries.remove();
 208
 209   int newPos = m_entries.at() + steps;
 210
 211   current = m_entries.at( newPos );
 212   if ( !current ) {
 213     kError() << "No History entry at position " << newPos << endl;
 214     return;
 215   }
 216
 217   if ( !current->view ) {
 218     kWarning() << "Empty history entry." ;
 219     return;
 220   }
 221
 222   if ( current->search ) {
 223     kDebug() << "History::goHistory(): search";
 224     current->view->lastSearch();
 225     return;
 226   }
 227
 228   if ( current->url.protocol() == QLatin1String("khelpcenter") ) {
 229     kDebug() << "History::goHistory(): internal";
 230     emit goInternalUrl( current->url );
 231     return;
 232   }
 233
 234   kDebug() << "History::goHistory(): restore state";
 235
 236   emit goUrl( current->url );
 237
 238   Entry h( *current );
 239   h.buffer.detach();
 240
 241   QDataStream stream( h.buffer );
 242
 243   h.view->closeUrl();
 244   updateCurrentEntry( h.view );
 245   h.view->browserExtension()->restoreState( stream );
 246
 247   updateActions();
 248 }
 249
 250 void History::fillBackMenu()
 251 {
 252   QMenu *menu = m_backAction->menu();
 253   menu->clear();
 254   fillHistoryPopup( menu, true, false, false );
 255 }
 256
 257 void History::fillForwardMenu()
 258 {
 259   QMenu *menu = m_forwardAction->menu();
 260   menu->clear();
 261   fillHistoryPopup( menu, false, true, false );
 262 }
 263
 264 void History::fillGoMenu()
 265 {
 266   KXmlGuiWindow *mainWindow = static_cast<KXmlGuiWindow *>( kapp->activeWindow() );
 267   QMenu *goMenu = dynamic_cast<QMenu *>( mainWindow->guiFactory()->container( QLatin1String( "go" ), mainWindow ) );
 268   if ( !goMenu || m_goMenuIndex == -1 )
 269     return;
 270
 271   for ( int i = goMenu->actions().count() - 1 ; i >= m_goMenuIndex; i-- )
 272     goMenu->removeAction( goMenu->actions()[i] );
 273
 274   // TODO perhaps smarter algorithm (rename existing items, create new ones only if not enough) ?
 275
 276   // Ok, we want to show 10 items in all, among which the current url...
 277
 278   if ( m_entries.count() <= 9 )
 279   {
 280     // First case: limited history in both directions -> show it all
 281     m_goMenuHistoryStartPos = m_entries.count() - 1; // Start right from the end
 282   } else
 283     // Second case: big history, in one or both directions
 284   {
 285     // Assume both directions first (in this case we place the current URL in the middle)
 286     m_goMenuHistoryStartPos = m_entries.at() + 4;
 287
 288     // Forward not big enough ?
 289     if ( m_entries.at() > (int)m_entries.count() - 4 )
 290       m_goMenuHistoryStartPos = m_entries.count() - 1;
 291   }
 292   Q_ASSERT( m_goMenuHistoryStartPos >= 0 && (uint)m_goMenuHistoryStartPos < m_entries.count() );
 293   m_goMenuHistoryCurrentPos = m_entries.at(); // for slotActivated
 294   fillHistoryPopup( goMenu, false, false, true, m_goMenuHistoryStartPos );
 295 }
 296
 297 void History::goMenuActivated( int id )
 298 {
 299   KXmlGuiWindow *mainWindow = static_cast<KXmlGuiWindow *>( kapp->activeWindow() );
 300   QMenu *goMenu = dynamic_cast<QMenu *>( mainWindow->guiFactory()->container( QLatin1String( "go" ), mainWindow ) );
 301   if ( !goMenu )
 302     return;
 303
 304   // 1 for first item in the list, etc.
 305   int index = goMenu->indexOf(id) - m_goMenuIndex + 1;
 306   if ( index > 0 )
 307   {
 308     kDebug(1400) << "Item clicked has index " << index;
 309     // -1 for one step back, 0 for don't move, +1 for one step forward, etc.
 310     int steps = ( m_goMenuHistoryStartPos+1 ) - index - m_goMenuHistoryCurrentPos; // make a drawing to understand this :-)
 311     kDebug(1400) << "Emit activated with steps = " << steps;
 312     goHistory( steps );
 313   }
 314 }
 315
 316 void History::fillHistoryPopup( QMenu *popup, bool onlyBack, bool onlyForward, bool checkCurrentItem, uint startPos )
 317 {
 318   Q_ASSERT ( popup ); // kill me if this 0... :/
 319
 320   Entry * current = m_entries.current();
 321   Q3PtrListIterator<Entry> it( m_entries );
 322   if (onlyBack || onlyForward)
 323   {
 324     it += m_entries.at(); // Jump to current item
 325     if ( !onlyForward ) --it; else ++it; // And move off it
 326   } else if ( startPos )
 327     it += startPos; // Jump to specified start pos
 328
 329   uint i = 0;
 330   while ( it.current() )
 331   {
 332     QString text = it.current()->title;
 333     text = KStringHandler::csqueeze(text, 50); //CT: squeeze
 334     text.replace( "&", "&&" );
 335     if ( checkCurrentItem && it.current() == current )
 336     {
 337       popup->addAction( text )->setChecked( true ); // no pixmap if checked
 338     } else
 339       popup->addAction( text );
 340     if ( ++i > 10 )
 341       break;
 342     if ( !onlyForward ) --it; else ++it;
 343   }
 344 }
 345
 346 bool History::canGoBack() const
 347 {
 348   return m_entries.at() > 0;
 349 }
 350
 351 bool History::canGoForward() const
 352 {
 353   return m_entries.at() != static_cast<int>( m_entries.count() ) - 1;
 354 }
 355
 356 #include "history.moc"
 357 // vim:ts=2:sw=2:et