MuteUnmuteMic/[Un]MuteMic/JFHotkeyManager.m

//
//  JFHotkeyManager.m
//  JFHotkeyManager
//
//  Created by Jason Frame on 23/02/2010.
//  Copyright 2010 Jason Frame. All rights reserved.
//

#import "JFHotkeyManager.h"

static OSStatus hotkeyHandler(EventHandlerCallRef hnd,
                              EventRef evt,
                              void *data) {
    
    EventHotKeyID hkID;
    GetEventParameter(evt, kEventParamDirectObject, typeEventHotKeyID, NULL, sizeof(hkID), NULL, &hkID);
    
    JFHotkeyManager *hkm = (__bridge JFHotkeyManager *)data;
    [hkm _dispatch:hkID.id];
    
    return noErr;
    
}

static NSMutableDictionary *keyMap;
static NSMutableDictionary *modMap;

static void mapKey(NSString *s, NSUInteger key) {
    keyMap[s] = @(key);
}

static void mapMod(NSString *s, NSUInteger mod) {
    modMap[s] = @(mod);
}


@implementation __JFHotkey
- (id)initWithHotkeyID:(UInt32)hotkeyID
                keyRef:(UInt32)keyRef
             modifiers:(UInt32)modifiers
                target:(id)target
                action:(SEL)selector {
    if (self = [super init]) {
        
        EventHotKeyID kID;
        kID.id = kID.signature = hotkeyID;
        
        RegisterEventHotKey(keyRef, modifiers, kID, GetApplicationEventTarget(), 0, &_ref);
        
        _target = target;
        _action = selector;
        
    }
    return self;
}

- (void)dealloc {
    UnregisterEventHotKey(_ref);
}

- (void)invoke {
    IMP imp = [_target methodForSelector:_action];
    void (*func)(id, SEL) = (void *)imp;
    func(_target, _action);
}
@end


@implementation JFHotkeyManager

+ (void)initialize {
    
    modMap = [[NSMutableDictionary alloc] init];
    keyMap = [[NSMutableDictionary alloc] init];
    
    // Is this guaranteed to be the same across systems/keyboards?
    // Probably not.
    
    //
    // Keys
    
    mapKey(@"a",        0x00);
    mapKey(@"b",        0x0B);
    mapKey(@"c",        0x09);
    mapKey(@"d",        0x02);
    mapKey(@"e",        0x0E);
    mapKey(@"f",        0x03);
    mapKey(@"g",        0x05);
    mapKey(@"h",        0x04);
    mapKey(@"i",        0x22);
    mapKey(@"j",        0x26);
    mapKey(@"k",        0x29);
    mapKey(@"l",        0x25);
    mapKey(@"m",        0x2E);
    mapKey(@"n",        0x2D);
    mapKey(@"o",        0x1F);
    mapKey(@"p",        0x23);
    mapKey(@"q",        0x0C);
    mapKey(@"r",        0x0F);
    mapKey(@"s",        0x01);
    mapKey(@"t",        0x11);
    mapKey(@"u",        0x20);
    mapKey(@"v",        0x09);
    mapKey(@"w",        0x0D);
    mapKey(@"x",        0x07);
    mapKey(@"y",        0x10);
    mapKey(@"z",        0x06);
    
    mapKey(@"0",        0x1D);
    mapKey(@"1",        0x12);
    mapKey(@"2",        0x13);
    mapKey(@"3",        0x14);
    mapKey(@"4",        0x15);
    mapKey(@"5",        0x17);
    mapKey(@"6",        0x16);
    mapKey(@"7",        0x1A);
    mapKey(@"8",        0x1C);
    mapKey(@"9",        0x19);
    
    mapKey(@",",        0x2B);
    mapKey(@".",        0x2F);
    mapKey(@"/",        0x2C);
    
    mapKey(@"f1",        0x7A);
    mapKey(@"f2",        0x79);
    mapKey(@"f3",        0x63);
    mapKey(@"f4",        0x76);
    mapKey(@"f5",        0x60);
    mapKey(@"f6",        0x61);
    mapKey(@"f7",        0x62);
    mapKey(@"f8",        0x64);
    mapKey(@"f9",        0x65);
    mapKey(@"f10",        0x6D);
    mapKey(@"f11",        0x67);
    mapKey(@"f12",        0x6F);
    mapKey(@"f13",        0x69);
    mapKey(@"f14",        0x6B);
    mapKey(@"f15",        0x71);
    
    mapKey(@"escape",    0x35);
    mapKey(@"esc",        0x35);
    mapKey(@"space",    0x31);
    mapKey(@"enter",    0x24);
    mapKey(@"tab",        0x30);
    mapKey(@"backspace",0x33);
    mapKey(@"bkspc",    0x33);
    
    mapKey(@"left",        0x7B);
    mapKey(@"right",    0x7C);
    mapKey(@"down",        0x7D);
    mapKey(@"up",        0x7E);
    
    //
    // Modifiers
    
    mapMod(@"apple",    cmdKey);
    
    mapMod(@"ctrl",        controlKey);
    mapMod(@"ctl",        controlKey);
    mapMod(@"control",    controlKey);
    
    mapMod(@"opt",        optionKey);
    mapMod(@"option",    optionKey);
    mapMod(@"alt",        optionKey);
    
    mapMod(@"cmd",        cmdKey);
    mapMod(@"command",    cmdKey);
    mapMod(@"apple",    cmdKey);
    
    mapMod(@"shift",    shiftKey);
    
}

- (id)init {
    if (self = [super init]) {
        
        _hotkeys = [[NSMutableDictionary alloc] init];
        _nextId = 1;
        
        EventTypeSpec evtType;
        evtType.eventClass = kEventClassKeyboard;
        evtType.eventKind = kEventHotKeyPressed;
        InstallApplicationEventHandler(&hotkeyHandler,
                                       1,
                                       &evtType,
                                       (__bridge void*)self,
                                       NULL);
        
    }
    return self;
}

- (JFHotKeyRef)bind:(NSString *)commandString
      target:(id)target
      action:(SEL)selector {
    
    UInt32 keyRef        = 0;
    UInt32 modifiers    = 0;
    
    NSArray *bits = [[commandString lowercaseString] componentsSeparatedByString:@" "];
    for (NSString *bit in bits) {
        
        NSNumber *code = modMap[bit];
        if (code != nil) {
            modifiers += [code unsignedIntValue];
            continue;
        }
        
        code = keyMap[bit];
        if (code != nil) {
            keyRef = [code unsignedIntValue];
            continue;
        }
        
    }
    
    return [self bindKeyRef:keyRef
              withModifiers:modifiers
                     target:target
                     action:selector];

}

- (JFHotKeyRef)bindKeyRef:(UInt32)keyRef
     withModifiers:(UInt32)modifiers
            target:(id)target
            action:(SEL)selector {
    
    UInt32 keyID = _nextId;
    _nextId++;
    
    __JFHotkey *hk = [[__JFHotkey alloc] initWithHotkeyID:keyID
                                                   keyRef:keyRef
                                                modifiers:modifiers
                                                   target:target
                                                   action:selector];
    
    _hotkeys[@(keyID)] = hk;
    
    return keyID;

}

- (void)unbind:(JFHotKeyRef)keyRef {
    [_hotkeys removeObjectForKey:@(keyRef)];
}

- (void)_dispatch:(NSUInteger)hotkeyId {
    [_hotkeys[@(hotkeyId)] invoke];
}

@end