/* This file is (c) 2013 Abs62
 * Part of GoldenDict. Licensed under GPLv3 or later, see the LICENSE file */

#include "hotkeywrapper.hh"
#include <ApplicationServices/ApplicationServices.h>

namespace MacKeyMapping
{
// Convert Qt key codes to Mac OS X native codes

struct ReverseMapEntry
{
  UniChar  character;
  UInt16   keyCode;
};

static struct ReverseMapEntry * mapping;
static int mapEntries = 0;

void createMapping()
{
  if( mapping == NULL )
  {
    TISInputSourceRef inputSourceRef = TISCopyInputSourceForLanguage( CFSTR( "en" ) );
    if ( !inputSourceRef )
      inputSourceRef = TISCopyCurrentKeyboardInputSource();
    if ( !inputSourceRef )
      return;

    CFDataRef dataRef = ( CFDataRef )TISGetInputSourceProperty( inputSourceRef,
                                     kTISPropertyUnicodeKeyLayoutData );
    if( !dataRef )
      return;

    const UCKeyboardLayout * keyboardLayoutPtr = ( const UCKeyboardLayout * )CFDataGetBytePtr( dataRef );
    if( !keyboardLayoutPtr )
      return;

    mapping = ( struct ReverseMapEntry * )calloc( 128 , sizeof(struct ReverseMapEntry) );
    if( !mapping )
      return;

    mapEntries = 0;

    for( int i = 0; i < 128; i++ )
    {
      UInt32 theDeadKeyState = 0;
      UniCharCount theLength = 0;
      if( UCKeyTranslate( keyboardLayoutPtr, i, kUCKeyActionDisplay, 0, LMGetKbdType(),
                            kUCKeyTranslateNoDeadKeysBit, &theDeadKeyState, 1, &theLength,
                            &mapping[ mapEntries ].character ) == noErr && theLength > 0 )
      {
        if( isprint( mapping[ mapEntries ].character ) )
        {
          mapping[ mapEntries++ ].keyCode = i;
        }
      }
    }
  }
}

quint32 qtKeyToNativeKey( quint32 key )
{
  createMapping();
  if( mapping == NULL )
    return 0;

  for( int i = 0; i < mapEntries; i++ )
  {
    if( mapping[ i ].character == key )
      return mapping[ i ].keyCode;
  }

  return 0;
}

} // namespace MacKeyMapping

static pascal OSStatus hotKeyHandler( EventHandlerCallRef /* nextHandler */, EventRef theEvent, void * userData )
{
  EventHotKeyID hkID;
  GetEventParameter( theEvent, kEventParamDirectObject, typeEventHotKeyID, NULL, sizeof(EventHotKeyID), NULL, &hkID );
  static_cast< HotkeyWrapper * >( userData )->activated( hkID.id );
  return noErr;
}

HotkeyWrapper::HotkeyWrapper( QObject *parent )
{
(void) parent;
  hotKeyFunction = NewEventHandlerUPP( hotKeyHandler );
  EventTypeSpec type;
  type.eventClass = kEventClassKeyboard;
  type.eventKind = kEventHotKeyPressed;
  InstallApplicationEventHandler( hotKeyFunction, 1, &type, this, &handlerRef );
  keyC = nativeKey( 'c' );
}

HotkeyWrapper::~HotkeyWrapper()
{
  unregister();
  RemoveEventHandler( handlerRef );
}

void HotkeyWrapper::waitKey2()
{
  state2 = false;
}

void HotkeyWrapper::activated( int hkId )
{
  if ( state2 )
  { // wait for 2nd key

    waitKey2(); // Cancel the 2nd-key wait stage

    if ( hkId == state2waiter.id + 1 ||
         ( hkId == state2waiter.id && state2waiter.key == state2waiter.key2 ) )
    {
      emit hotkeyActivated( state2waiter.handle );
      return;
    }
  }

  for ( int i = 0; i < hotkeys.count(); i++ )
  {
    HotkeyStruct &hs = hotkeys[ i ];
    if( hkId == hs.id )
    {
      if( hs.key == keyC && hs.modifier == cmdKey )
      {
        // If that was a copy-to-clipboard shortcut, re-emit it back so it could
        // reach its original destination so it could be acted upon.
        UnregisterEventHotKey( hs.hkRef );

        sendCmdC();

        EventHotKeyID hotKeyID;
        hotKeyID.signature = 'GDHK';
        hotKeyID.id = hs.id;

        RegisterEventHotKey( hs.key, hs.modifier, hotKeyID, GetApplicationEventTarget(), 0, &hs.hkRef );
      }

      if ( hs.key2 == 0 ) {
         emit hotkeyActivated( hs.handle );
         return;
      }

      state2 = true;
      state2waiter = hs;
      QTimer::singleShot( 500, this, SLOT( waitKey2() ) );
      return;
    }
  }

  state2 = false;
  return;
}

void HotkeyWrapper::unregister()
{
  for ( int i = 0; i < hotkeys.count(); i++ )
  {
    HotkeyStruct const & hk = hotkeys.at( i );

    UnregisterEventHotKey( hk.hkRef );

    if ( hk.key2 && hk.key2 != hk.key )
      UnregisterEventHotKey( hk.hkRef2 );
  }

  (static_cast< QHotkeyApplication * >( qApp ))->unregisterWrapper( this );
}

bool HotkeyWrapper::setGlobalKey( int key, int key2, Qt::KeyboardModifiers modifier, int handle )
{
  if ( !key )
    return false; // We don't monitor empty combinations

  quint32 vk = nativeKey( key );

  if( vk == 0 )
    return false;

  quint32 vk2 = key2 ? nativeKey( key2 ) : 0;

  static int nextId = 1;
  if( nextId > 0xBFFF - 1 )
    nextId = 1;

  quint32 mod = 0;
  if( modifier & Qt::CTRL )
    mod |= cmdKey;
  if( modifier & Qt::ALT )
    mod |= optionKey;
  if( modifier & Qt::SHIFT )
    mod |= shiftKey;
  if( modifier & Qt::META )
    mod |= controlKey;

  hotkeys.append( HotkeyStruct( vk, vk2, mod, handle, nextId ) );
  HotkeyStruct &hk = hotkeys.last();

  EventHotKeyID hotKeyID;
  hotKeyID.signature = 'GDHK';
  hotKeyID.id = nextId;

  OSStatus ret = RegisterEventHotKey( vk, mod, hotKeyID, GetApplicationEventTarget(), 0, &hk.hkRef );
  if ( ret != 0 )
    return false;

  if ( vk2 && vk2 != vk )
  {
    hotKeyID.id = nextId + 1;
    ret = RegisterEventHotKey( vk2, mod, hotKeyID, GetApplicationEventTarget(), 0, &hk.hkRef2 );
  }

  nextId += 2;

  return ret == 0;
}

quint32 HotkeyWrapper::nativeKey( int key )
{
  switch( key ) {
    case Qt::Key_Escape:      return 0x35;
    case Qt::Key_Tab:         return 0x30;
    case Qt::Key_Backspace:   return 0x33;
    case Qt::Key_Return:      return 0x24;
    case Qt::Key_Enter:       return 0x4c;
    case Qt::Key_Delete:      return 0x75;
    case Qt::Key_Clear:       return 0x47;
    case Qt::Key_Home:        return 0x73;
    case Qt::Key_End:         return 0x77;
    case Qt::Key_Left:        return 0x7b;
    case Qt::Key_Up:          return 0x7e;
    case Qt::Key_Right:       return 0x7c;
    case Qt::Key_Down:        return 0x7d;
    case Qt::Key_PageUp:      return 0x74;
    case Qt::Key_PageDown:    return 0x79;
    case Qt::Key_CapsLock:    return 0x57;
    case Qt::Key_F1:          return 0x7a;
    case Qt::Key_F2:          return 0x78;
    case Qt::Key_F3:          return 0x63;
    case Qt::Key_F4:          return 0x76;
    case Qt::Key_F5:          return 0x60;
    case Qt::Key_F6:          return 0x61;
    case Qt::Key_F7:          return 0x62;
    case Qt::Key_F8:          return 0x64;
    case Qt::Key_F9:          return 0x65;
    case Qt::Key_F10:         return 0x6d;
    case Qt::Key_F11:         return 0x67;
    case Qt::Key_F12:         return 0x6f;
    case Qt::Key_F13:         return 0x69;
    case Qt::Key_F14:         return 0x6b;
    case Qt::Key_F15:         return 0x71;
    case Qt::Key_Help:        return 0x72;
    default:;
  }
  return MacKeyMapping::qtKeyToNativeKey( QChar( key ).toLower().toLatin1() );
}

void HotkeyWrapper::sendCmdC()
{
  CGEventFlags flags = kCGEventFlagMaskCommand;
  CGEventRef ev;
  CGEventSourceRef source = CGEventSourceCreate( kCGEventSourceStateCombinedSessionState );

  //press down
  ev = CGEventCreateKeyboardEvent( source, keyC, true );
  CGEventSetFlags( ev, flags | CGEventGetFlags( ev ) ); //combine flags
  CGEventPost( kCGAnnotatedSessionEventTap, ev );
  CFRelease( ev );

  //press up
  ev = CGEventCreateKeyboardEvent( source, keyC, false );
  CGEventSetFlags( ev, flags | CGEventGetFlags( ev ) ); //combine flags
  CGEventPost( kCGAnnotatedSessionEventTap, ev );
  CFRelease( ev );

  CFRelease( source );
}

EventHandlerUPP HotkeyWrapper::hotKeyFunction = NULL;