SRKeyCodeTransformer.m

//
//  SRKeyCodeTransformer.h
//  ShortcutRecorder
//
//  Copyright 2006-2007 Contributors. All rights reserved.
//
//  License: BSD
//
//  Contributors:
//      David Dauer
//      Jesper
//      Jamie Kirkpatrick

#import "SRKeyCodeTransformer.h"
#import <Carbon/Carbon.h>
#import <CoreServices/CoreServices.h>
#import "SRCommon.h"

static NSMutableDictionary *stringToKeyCodeDict = nil;
static NSDictionary *keyCodeToStringDict = nil;
static NSArray *padKeysArray        = nil;

@interface SRKeyCodeTransformer (Private)
+ (void)regenerateStringToKeyCodeMapping;
@end

#pragma mark -

@implementation SRKeyCodeTransformer

//----------------------------------------------------------
//  initialize
//----------------------------------------------------------
+ (void)initialize;
{
    if (self != [SRKeyCodeTransformer class]) return;

    // Some keys need a special glyph
    keyCodeToStringDict = [[NSDictionary alloc] initWithObjectsAndKeys:
                           @"F1", SRInt(122),
                           @"F2", SRInt(120),
                           @"F3", SRInt(99),
                           @"F4", SRInt(118),
                           @"F5", SRInt(96),
                           @"F6", SRInt(97),
                           @"F7", SRInt(98),
                           @"F8", SRInt(100),
                           @"F9", SRInt(101),
                           @"F10", SRInt(109),
                           @"F11", SRInt(103),
                           @"F12", SRInt(111),
                           @"F13", SRInt(105),
                           @"F14", SRInt(107),
                           @"F15", SRInt(113),
                           @"F16", SRInt(106),
                           SRLoc(@"Space"), SRInt(49),
                           SRChar((unichar)KeyboardDeleteLeftGlyph), SRInt(51),
                           SRChar((unichar)KeyboardDeleteRightGlyph), SRInt(117),
                           SRChar((unichar)KeyboardPadClearGlyph), SRInt(71),
                           SRChar((unichar)KeyboardLeftArrowGlyph), SRInt(123),
                           SRChar((unichar)KeyboardRightArrowGlyph), SRInt(124),
                           SRChar((unichar)KeyboardUpArrowGlyph), SRInt(126),
                           SRChar((unichar)KeyboardDownArrowGlyph), SRInt(125),
                           SRChar((unichar)KeyboardSoutheastArrowGlyph), SRInt(119),
                           SRChar((unichar)KeyboardNorthwestArrowGlyph), SRInt(115),
                           SRChar((unichar)KeyboardEscapeGlyph), SRInt(53),
                           SRChar((unichar)KeyboardPageDownGlyph), SRInt(121),
                           SRChar((unichar)KeyboardPageUpGlyph), SRInt(116),
                           SRChar((unichar)KeyboardReturnR2LGlyph), SRInt(36),
                           SRChar((unichar)KeyboardReturnGlyph), SRInt(76),
                           SRChar((unichar)KeyboardTabRightGlyph), SRInt(48),
                           SRChar((unichar)KeyboardHelpGlyph), SRInt(114),
                           nil];

    // We want to identify if the key was pressed on the numpad
    padKeysArray = [[NSArray alloc] initWithObjects:
                    SRInt(65), // ,
                    SRInt(67), // *
                    SRInt(69), // +
                    SRInt(75), // /
                    SRInt(78), // -
                    SRInt(81), // =
                    SRInt(82), // 0
                    SRInt(83), // 1
                    SRInt(84), // 2
                    SRInt(85), // 3
                    SRInt(86), // 4
                    SRInt(87), // 5
                    SRInt(88), // 6
                    SRInt(89), // 7
                    SRInt(91), // 8
                    SRInt(92), // 9
                    nil];

    // generate the string to keycode mapping dict...
    stringToKeyCodeDict = [[NSMutableDictionary alloc] init];
    [self regenerateStringToKeyCodeMapping];
}

//----------------------------------------------------------
//  allowsReverseTransformation
//----------------------------------------------------------
+ (BOOL)allowsReverseTransformation {
    return YES;
}

//----------------------------------------------------------
//  transformedValueClass
//----------------------------------------------------------
+ (Class)transformedValueClass;
{
    return [NSString class];
}

//----------------------------------------------------------
//  transformedValue:
//----------------------------------------------------------
- (id)transformedValue:(id)value {
    if (![value isKindOfClass:[NSNumber class]]) return nil;

    // Can be -1 when empty
    signed short keyCode = [value shortValue];

    if (keyCode < 0) return nil;

    // We have some special gylphs for some special keys...
    NSString *unmappedString = [keyCodeToStringDict objectForKey:SRInt(keyCode)];

    if (unmappedString != nil) return unmappedString;

    BOOL isPadKey = [padKeysArray containsObject:SRInt(keyCode)];
    KeyboardLayoutRef currentLayoutRef;
    KeyboardLayoutKind currentLayoutKind;
    OSStatus err;

    err = KLGetCurrentKeyboardLayout(&currentLayoutRef);

    if (err != noErr) return nil;

    err = KLGetKeyboardLayoutProperty(currentLayoutRef, kKLKind, (const void **)&currentLayoutKind);

    if (err != noErr) return nil;

    UInt32 keysDown = 0;

    if (currentLayoutKind == kKLKCHRKind) {
        Handle kchrHandle;

        err = KLGetKeyboardLayoutProperty(currentLayoutRef, kKLKCHRData, (const void **)&kchrHandle);

        if (err != noErr) return nil;

        UInt32 charCode = KeyTranslate(kchrHandle, keyCode, &keysDown);

        if (keysDown != 0) charCode = KeyTranslate(kchrHandle, keyCode, &keysDown);

        char theChar = (charCode & 0x00FF);

        NSString *keyString = [[[[NSString alloc] initWithData:[NSData dataWithBytes:&theChar length:1] encoding:NSMacOSRomanStringEncoding] autorelease] uppercaseString];

        return (isPadKey ? [NSString stringWithFormat:SRLoc(@"Pad %@"), keyString] : keyString);
    } else { // kKLuchrKind, kKLKCHRuchrKind
//        UCKeyboardLayout *keyboardLayout = NULL;
//        err = KLGetKeyboardLayoutProperty(currentLayoutRef, kKLuchrData, (const void **)&keyboardLayout);

        if (err != noErr) return nil;

//        UniCharCount length = 4, realLength;
        UniChar chars[4];

//        err = UCKeyTranslate(keyboardLayout,
//                             keyCode,
//                             kUCKeyActionDisplay,
//                             0,
//                             LMGetKbdType(),
//                             kUCKeyTranslateNoDeadKeysBit,
//                             &keysDown,
//                             length,
//                             &realLength,
//                             chars);

        NSString *keyString = [[NSString stringWithCharacters:chars length:1] uppercaseString];

        return (isPadKey ? [NSString stringWithFormat:SRLoc(@"Pad %@"), keyString] : keyString);
    }

    return nil;
}

//----------------------------------------------------------
//  reverseTransformedValue:
//----------------------------------------------------------
- (id)reverseTransformedValue:(id)value {
    if (![value isKindOfClass:[NSString class]]) return nil;

    // try and retrieve a mapped keycode from the reverse mapping dict...
    return [stringToKeyCodeDict objectForKey:value];
}

@end

#pragma mark -

@implementation SRKeyCodeTransformer (Private)

//----------------------------------------------------------
//  regenerateStringToKeyCodeMapping:
//----------------------------------------------------------
+ (void)regenerateStringToKeyCodeMapping;
{
    SRKeyCodeTransformer *transformer = [[[self alloc] init] autorelease];
    [stringToKeyCodeDict removeAllObjects];

    // loop over every keycode (0 - 127) finding its current string mapping...
    unsigned i;

    for (i = 0U; i < 128U; i++) {
        NSNumber *keyCode = [NSNumber numberWithUnsignedInt:i];
        NSString *string = [transformer transformedValue:keyCode];

        if ( (string) && ([string length]) ) {
            [stringToKeyCodeDict setObject:keyCode forKey:string];
        }
    }
}

@end