/*

 * Java ATK Wrapper for GNOME

 * Copyright (C) 2009 Sun Microsystems Inc.

 * Copyright (C) 2015 Magdalen Berns <m.berns@thismagpie.com>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

 */

package org.GNOME.Accessibility;

import java.awt.*;

import java.awt.event.*;

import java.beans.*;

import java.io.*;

import javax.accessibility.*;

import java.awt.Toolkit;

public class AtkWrapper {

  static boolean accessibilityEnabled = false;

  static {

    try {

      Process p = Runtime.getRuntime().exec("@XPROP@ -root");

      BufferedReader b = new BufferedReader(new InputStreamReader (p.getInputStream ()));

      String result;

      while ((result = b.readLine()) != null) {

        if (result.indexOf("AT_SPI_IOR") >= 0 || result.indexOf("AT_SPI_BUS") >= 0) {

          System.loadLibrary("atk-wrapper");

          if (AtkWrapper.initNativeLibrary())

            accessibilityEnabled = true;

          break;

        }

      }

    } catch (Exception e) {

      e.printStackTrace();

      e.getCause();

    }

  }

 /**

  * winAdapter

  *

  * <http://docs.oracle.com/javase/8/docs/api/java/awt/event/WindowAdapter.html>

  * <http://docs.oracle.com/javase/8/docs/api/java/awt/event/WindowEvent.html>

  */

  final WindowAdapter winAdapter = new WindowAdapter() {

  /**

    * windowActivated:

    *                    Invoked when a Window becomes the active Window.

    *                    Only a Frame or a Dialog can be the active Window. The

    *                    native windowing system may denote the active Window

    *                    or its children with special decorations, such as a

    *                    highlighted title bar. The active Window is always either

    *                    the focused Window, or the first Frame or Dialog that is

    *                    an owner of the focused Window.

    * @param e A WindowEvent object

    */

    public void windowActivated(WindowEvent e) {

      Object o = e.getSource();

      if ( o instanceof javax.accessibility.Accessible ) {

        AccessibleContext ac = ((javax.accessibility.Accessible)o).getAccessibleContext();

        AtkWrapper.windowActivate(ac);

      }

    }

   /**

    * windowDeactivated:

    *                    Invoked when a Window is no longer the active Window.

    *                    Only a Frame or a Dialog can be the active Window. The

    *                    native windowing system may denote the active Window

    *                    or its children with special decorations, such as a

    *                    highlighted title bar. The active Window is always either

    *                    the focused Window, or the first Frame or Dialog that is

    *                    an owner of the focused Window.

    * @param e A WindowEvent object

    */

    public void windowDeactivated(WindowEvent e) {

      Object o = e.getSource();

      if (o instanceof javax.accessibility.Accessible) {

        AccessibleContext ac = ((javax.accessibility.Accessible)o).getAccessibleContext();

        AtkWrapper.windowDeactivate(ac);

      }

    }

   /**

    * windowStateChanged:

    *                     Invoked when a window state is changed.

    *

    * @param e A WindowEvent object

    */

    public void windowStateChanged(WindowEvent e) {

      Object o = e.getSource();

      if (o instanceof javax.accessibility.Accessible) {

        AccessibleContext ac = ((javax.accessibility.Accessible)o).getAccessibleContext();

        AtkWrapper.windowStateChange(ac);

        if( (e.getNewState() & Frame.MAXIMIZED_BOTH) == Frame.MAXIMIZED_BOTH ) {

          AtkWrapper.windowMaximize(ac);

        }

      }

    }

   /**

    * windowDeiconified:

    *                   Invoked when a window is deiconified.

    * @param e A WindowEvent instance

    */

    public void windowDeiconified(WindowEvent e) {

      Object o = e.getSource();

      if (o instanceof javax.accessibility.Accessible) {

        AccessibleContext ac = ((javax.accessibility.Accessible)o).getAccessibleContext();

        AtkWrapper.windowRestore(ac);

      }

    }

   /**

    *  windowIconified:

    *                  Invoked when a window is iconified.

    * @param e A WindowEvent instance

    */

    public void windowIconified(WindowEvent e) {

      Object o = e.getSource();

      if (o instanceof javax.accessibility.Accessible) {

        AccessibleContext ac = ((javax.accessibility.Accessible)o).getAccessibleContext();

        AtkWrapper.windowMinimize(ac);

      }

    }

   /**

    *  windowOpened

    * @param e A WindowEvent object

    */

    public void windowOpened(WindowEvent e) {

      Object o = e.getSource();

      if ( o instanceof javax.accessibility.Accessible ) {

        boolean isToplevel = isToplevel(o);

        AccessibleContext ac = ((javax.accessibility.Accessible)o).getAccessibleContext();

        AtkWrapper.windowOpen(ac, isToplevel);

      }

    }

   /**

    * windowClosed:

    *              Invoked when a window has been closed.

    * @param e A WindowEvent object

    */

    public void windowClosed(WindowEvent e) {

      Object o = e.getSource();

      if (o instanceof javax.accessibility.Accessible) {

        boolean isToplevel = isToplevel(o);

        AccessibleContext ac = ((javax.accessibility.Accessible)o).getAccessibleContext();

        AtkWrapper.windowClose(ac, isToplevel);

      }

    }

   /**

    * windowClosing:

    *              Invoked when a window is in the process of being closed.

    * @param e A WindowEvent object

    */

    public void windowClosing(WindowEvent e) {

      Object o = e.getSource();

      if (o instanceof javax.accessibility.Accessible) {

        boolean isToplevel = isToplevel(o);

        AccessibleContext ac = ((javax.accessibility.Accessible)o).getAccessibleContext();

        AtkWrapper.windowClose(ac, isToplevel);

      }

    }

   /**

    * windowGainedFocus:

    *                   Invoked when the Window is set to be the focused Window,

    *                   which means that the Window, or one of its subcomponents,

    *                   will receive keyboard events.

    * @param e A WindowEvent object

    */

    public void windowGainedFocus(WindowEvent e) {

    }

    public void windowLostFocus(WindowEvent e) {

    }

  }; // Close WindowAdapter brace

 /**

  * isToplevel

  * @param o an instance

  * @return true if instance is of a window, frame or dialogue object

  *         false otherwise.

  */

  public static boolean isToplevel(Object o) {

    boolean isToplevel = false;

    if (o instanceof java.awt.Window ||

        o instanceof java.awt.Frame ||

        o instanceof java.awt.Dialog) {

      isToplevel = true;

    }

    return isToplevel;

  }

  final AWTEventListener globalListener = new AWTEventListener() {

    private boolean firstEvent = true;

    public void eventDispatched(AWTEvent e) {

      if (firstEvent && accessibilityEnabled) {

        firstEvent = false;

        try {

          AtkWrapper.loadAtkBridge();

        } catch (Exception ex) {

          ex.printStackTrace();

        }

      }

      if(e instanceof WindowEvent) {

        switch( e.getID() ) {

        case WindowEvent.WINDOW_OPENED:

          Window win = ((WindowEvent)e).getWindow();

          win.addWindowListener(winAdapter);

          win.addWindowStateListener(winAdapter);

          win.addWindowFocusListener(winAdapter);

          break;

        case WindowEvent.WINDOW_LOST_FOCUS:

          AtkWrapper.dispatchFocusEvent(null);

          break;

        default:

          break;

        }

      } else if(e instanceof ContainerEvent ) {

        switch( e.getID() ) {

          case ContainerEvent.COMPONENT_ADDED:

          {

            java.awt.Component c = ((ContainerEvent)e).getChild();

            if (c instanceof javax.accessibility.Accessible) {

              AccessibleContext ac = ((javax.accessibility.Accessible)c).getAccessibleContext();

              AtkWrapper.componentAdded(ac);

            }

            break;

          }

          case ContainerEvent.COMPONENT_REMOVED:

          {

            java.awt.Component c = ((ContainerEvent)e).getChild();

            if (c instanceof javax.accessibility.Accessible) {

              AccessibleContext ac = ((javax.accessibility.Accessible)c).getAccessibleContext();

              AtkWrapper.componentRemoved(ac);

            }

            break;

          }

        default:

          break;

        }

      } else if(e instanceof FocusEvent) {

        switch(e.getID()) {

        case FocusEvent.FOCUS_GAINED:

          AtkWrapper.dispatchFocusEvent(e.getSource());

          break;

        default:

          break;

        }

      }

    }

  };

  static AccessibleContext oldSourceContext = null;

  static AccessibleContext savedSourceContext= null;

  static AccessibleContext oldPaneContext = null;

 /**

  * dispatchFocusEvent

  * @param eventSource An instance of the event source object.

  */

  static void dispatchFocusEvent(Object eventSource) {

    if (eventSource == null) {

      oldSourceContext = null;

      return;

    }

    AccessibleContext ctx;

    try {

      if (eventSource instanceof AccessibleContext) {

        ctx = (AccessibleContext)eventSource;

      } else if (eventSource instanceof javax.accessibility.Accessible) {

        ctx = ((javax.accessibility.Accessible)eventSource).getAccessibleContext();

      } else {

        return;

      }

      if (ctx == oldSourceContext) {

        return;

      }

      if (oldSourceContext != null) {

        AccessibleRole role = oldSourceContext.getAccessibleRole();

        if (role == AccessibleRole.MENU || role == AccessibleRole.MENU_ITEM) {

          String jrootpane = "javax.swing.JRootPane$AccessibleJRootPane";

          String name = ctx.getClass().getName();

          if (jrootpane.compareTo(name) == 0) {

            oldPaneContext = ctx;

            return;

          }

        }

        savedSourceContext = ctx;

      } else if (oldPaneContext == ctx) {

      ctx = savedSourceContext;

      } else {

      savedSourceContext = ctx;

      }

      oldSourceContext = ctx;

      AccessibleRole role = ctx.getAccessibleRole();

      if (role == AccessibleRole.PAGE_TAB_LIST) {

        AccessibleSelection accSelection = ctx.getAccessibleSelection();

        if (accSelection != null && accSelection.getAccessibleSelectionCount() > 0) {

          Object child = accSelection.getAccessibleSelection(0);

          if (child instanceof AccessibleContext) {

            ctx = (AccessibleContext)child;

          } else if (child instanceof javax.accessibility.Accessible) {

            ctx = ((javax.accessibility.Accessible)child).getAccessibleContext();

          } else {

            return;

          }

        }

      }

      focusNotify(ctx);

    } catch (Exception e) {

        e.printStackTrace();

    }

  }

  final Toolkit toolkit = Toolkit.getDefaultToolkit();

  static PropertyChangeListener propertyChangeListener = new PropertyChangeListener() {

   /**

    * propertyChange:

    * @param e An instance of the PropertyChangeEvent object.

    */

    public void propertyChange(PropertyChangeEvent e) {

      Object o = e.getSource();

      AccessibleContext ac;

      if (o instanceof AccessibleContext) {

        ac = (AccessibleContext)o;

      } else if (o instanceof javax.accessibility.Accessible) {

        ac = ((javax.accessibility.Accessible)o).getAccessibleContext();

      } else {

        return;

      }

      Object oldValue = e.getOldValue();

      Object newValue = e.getNewValue();

      String propertyName = e.getPropertyName();

      if( propertyName.equals(AccessibleContext.ACCESSIBLE_CARET_PROPERTY) ) {

        Object[] args = new Object[1];

        args[0] = newValue;

        emitSignal(ac, AtkSignal.TEXT_CARET_MOVED, args);

      } else if( propertyName.equals(AccessibleContext.ACCESSIBLE_TEXT_PROPERTY) ) {

        if (newValue == null) {

          return;

        }

        if (newValue instanceof Integer) {

          Object[] args = new Object[1];

          args[0] = newValue;

          emitSignal(ac, AtkSignal.TEXT_PROPERTY_CHANGED, args);

        }

				/*

				if (oldValue == null && newValue != null) { //insertion event

					if (!(newValue instanceof AccessibleTextSequence)) {

						return;

					}

					AccessibleTextSequence newSeq = (AccessibleTextSequence)newValue;

					Object[] args = new Object[2];

					args[0] = new Integer(newSeq.startIndex);

					args[1] = new Integer(newSeq.endIndex - newSeq.startIndex);

					emitSignal(ac, AtkSignal.TEXT_PROPERTY_CHANGED_INSERT, args);

				} else if (oldValue != null && newValue == null) { //deletion event

					if (!(oldValue instanceof AccessibleTextSequence)) {

						return;

					}

					AccessibleTextSequence oldSeq = (AccessibleTextSequence)oldValue;

					Object[] args = new Object[2];

					args[0] = new Integer(oldSeq.startIndex);

					args[1] = new Integer(oldSeq.endIndex - oldSeq.startIndex);

					emitSignal(ac, AtkSignal.TEXT_PROPERTY_CHANGED_DELETE, args);

				} else if (oldValue != null && newValue != null) { //replacement event

					//It seems ATK does not support "replace" currently

					return;

				}*/

      } else if( propertyName.equals(AccessibleContext.ACCESSIBLE_CHILD_PROPERTY) ) {

        if (oldValue == null && newValue != null) { //child added

          AccessibleContext child_ac;

          if (newValue instanceof javax.accessibility.Accessible) {

            child_ac = ((javax.accessibility.Accessible)newValue).getAccessibleContext();

          } else {

            return;

          }

          Object[] args = new Object[2];

          args[0] = new Integer(child_ac.getAccessibleIndexInParent());

          args[1] = child_ac;

          emitSignal(ac, AtkSignal.OBJECT_CHILDREN_CHANGED_ADD, args);

        } else if (oldValue != null && newValue == null) { //child removed

          AccessibleContext child_ac;

          if (oldValue instanceof javax.accessibility.Accessible) {

            child_ac = ((javax.accessibility.Accessible)oldValue).getAccessibleContext();

          } else {

            return;

          }

          Object[] args = new Object[2];

          args[0] = new Integer(child_ac.getAccessibleIndexInParent());

          args[1] = child_ac;

          emitSignal(ac, AtkSignal.OBJECT_CHILDREN_CHANGED_REMOVE, args);

        }

      } else if( propertyName.equals(AccessibleContext.ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY) ) {

        AccessibleContext child_ac;

        if (newValue instanceof javax.accessibility.Accessible) {

          child_ac = ((javax.accessibility.Accessible)newValue).getAccessibleContext();

        } else {

          return;

        }

        Object[] args = new Object[1];

        args[0] = child_ac;

        emitSignal(ac, AtkSignal.OBJECT_ACTIVE_DESCENDANT_CHANGED, args);

        } else if( propertyName.equals(AccessibleContext.ACCESSIBLE_SELECTION_PROPERTY) ) {

          boolean isTextEvent = false;

          AccessibleRole role = ac.getAccessibleRole();

          if ((role == AccessibleRole.TEXT) ||

              role.toDisplayString(java.util.Locale.US).equalsIgnoreCase("paragraph")) {

            isTextEvent = true;

          } else if (role == AccessibleRole.MENU_BAR) {

            dispatchFocusEvent(o);

          } else if (role == AccessibleRole.PAGE_TAB_LIST) {

            AccessibleSelection selection = ac.getAccessibleSelection();

            if (selection != null &&

                selection.getAccessibleSelectionCount() > 0) {

              java.lang.Object child = selection.getAccessibleSelection(0);

              dispatchFocusEvent(child);

            }

          }

          if (!isTextEvent) {

            emitSignal(ac, AtkSignal.OBJECT_SELECTION_CHANGED, null);

          }

        } else if( propertyName.equals(AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY) ) {

          //emitSignal(ac, AtkSignal.OBJECT_VISIBLE_DATA_CHANGED, null);

        }else if( propertyName.equals(AccessibleContext.ACCESSIBLE_ACTION_PROPERTY) ) {

          Object[] args = new Object[2];

          args[0] = oldValue;

          args[1] = newValue;

          emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_ACTIONS, args);

        }else if( propertyName.equals(AccessibleContext.ACCESSIBLE_VALUE_PROPERTY) ) {

          if (oldValue instanceof Number && newValue instanceof Number) {

            Object[] args = new Object[2];

            args[0] = new Double(((Number)oldValue).doubleValue());

            args[1] = new Double(((Number)newValue).doubleValue());

            emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_VALUE, args);

          }

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_DESCRIPTION_PROPERTY)) {

        emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_DESCRIPTION, null);

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_NAME_PROPERTY)) {

        emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_NAME, null);

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_HYPERTEXT_OFFSET)) {

        emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_HYPERTEXT_OFFSET, null);

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_TABLE_MODEL_CHANGED)) {

        emitSignal(ac, AtkSignal.TABLE_MODEL_CHANGED, null);

      } else if( propertyName.equals(AccessibleContext.ACCESSIBLE_TABLE_CAPTION_CHANGED)) {

        emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_TABLE_CAPTION, null);

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_TABLE_SUMMARY_CHANGED)) {

        emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_TABLE_SUMMARY, null);

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_TABLE_COLUMN_HEADER_CHANGED)) {

        emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_TABLE_COLUMN_HEADER, null);

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_TABLE_COLUMN_DESCRIPTION_CHANGED) ) {

        emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_TABLE_COLUMN_DESCRIPTION, null);

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_TABLE_ROW_HEADER_CHANGED)) {

        emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_TABLE_ROW_HEADER, null);

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_TABLE_ROW_DESCRIPTION_CHANGED)) {

        emitSignal(ac, AtkSignal.OBJECT_PROPERTY_CHANGE_ACCESSIBLE_TABLE_ROW_DESCRIPTION, null);

      } else if(propertyName.equals(AccessibleContext.ACCESSIBLE_STATE_PROPERTY)) {

        javax.accessibility.Accessible parent = ac.getAccessibleParent();

        javax.accessibility.AccessibleRole role = ac.getAccessibleRole();

        javax.accessibility.AccessibleRole parent_role = null;

        if (parent != null) {

          parent_role = parent.getAccessibleContext().getAccessibleRole();

        }

        if (role != null) {

          if (newValue == javax.accessibility.AccessibleState.FOCUSED ||

              newValue == javax.accessibility.AccessibleState.SELECTED) {

            dispatchFocusEvent(o);

          }

        }

        AccessibleState state;

        boolean value = false;

        if (newValue != null) {

          state = (AccessibleState)newValue;

          value = true;

        } else {

          state = (AccessibleState)oldValue;

          value = false;

        }

        if (state == AccessibleState.COLLAPSED) {

          state = AccessibleState.EXPANDED;

          value = false;

        }

        if(parent instanceof javax.swing.JComboBox && oldValue ==

           javax.accessibility.AccessibleState.VISIBLE) {

          objectStateChange(ac, AccessibleState.SHOWING, value);

        }

        objectStateChange(ac, state, value);

        if (parent instanceof javax.swing.JComboBox && newValue ==

            javax.accessibility.AccessibleState.VISIBLE && oldValue == null) {

          objectStateChange(ac, AccessibleState.SHOWING, value);

        }

      }

    }

  };

  public static void registerPropertyChangeListener(AccessibleContext ac) {

    if (ac != null) {

      try {

        ac.addPropertyChangeListener(propertyChangeListener);

      } catch (Exception e){

        e.printStackTrace();

      }

    }

  }

  public native static boolean initNativeLibrary();

  public native static void loadAtkBridge();

  public native static void focusNotify(javax.accessibility.AccessibleContext ac);

  public native static void windowOpen(javax.accessibility.AccessibleContext ac,

                                       boolean isToplevel);

  public native static void windowClose(javax.accessibility.AccessibleContext ac,

                                        boolean isToplevel);

  public native static void windowMinimize(javax.accessibility.AccessibleContext ac);

  public native static void windowMaximize(javax.accessibility.AccessibleContext ac);

  public native static void windowRestore(javax.accessibility.AccessibleContext ac);

  public native static void windowActivate(javax.accessibility.AccessibleContext ac);

  public native static void windowDeactivate(javax.accessibility.AccessibleContext ac);

  public native static void windowStateChange(javax.accessibility.AccessibleContext ac);

  public native static void emitSignal(javax.accessibility.AccessibleContext ac, int id, Object[] args);

  public native static void objectStateChange(javax.accessibility.AccessibleContext ac,

                                              java.lang.Object state, boolean value);

  public native static void componentAdded(javax.accessibility.AccessibleContext ac);

  public native static void componentRemoved(javax.accessibility.AccessibleContext ac);

  public native static boolean dispatchKeyEvent(AtkKeyEvent e);

  public static void printLog(String str) {

    System.out.println(str);

  }

  public AtkWrapper() {

    if (!accessibilityEnabled)

      return;

    toolkit.addAWTEventListener(globalListener,

                                AWTEvent.WINDOW_EVENT_MASK |

                                AWTEvent.FOCUS_EVENT_MASK |

                                AWTEvent.CONTAINER_EVENT_MASK);

    toolkit.getSystemEventQueue().push(new EventQueue() {

      boolean previousPressConsumed = false;

      public void dispatchEvent(AWTEvent e) {

        if (e instanceof KeyEvent) {

          if (e.getID() == KeyEvent.KEY_PRESSED) {

            boolean isConsumed = AtkWrapper.dispatchKeyEvent(new AtkKeyEvent((KeyEvent)e));

            if (isConsumed) {

              previousPressConsumed = true;

              return;

            }

          } else if (e.getID() == KeyEvent.KEY_TYPED) {

            if (previousPressConsumed) {

              return;

            }

          } else if (e.getID() == KeyEvent.KEY_RELEASED) {

            boolean isConsumed = AtkWrapper.dispatchKeyEvent(new AtkKeyEvent((KeyEvent)e));

            previousPressConsumed = false;

            if (isConsumed) {

              return;

            }

          }

        }

        super.dispatchEvent(e);

      }

    });

  }

  public static void main(String args[]) {

    new AtkWrapper();

  }

}