jens@0: //
jens@0: //  Target.m
jens@0: //  MYUtilities
jens@0: //
jens@0: //  Created by Jens Alfke on 2/11/08.
jens@0: //  Copyright 2008 Jens Alfke. All rights reserved.
jens@0: //
jens@0: 
jens@0: #import "Target.h"
jens@0: 
jens@0: 
jens@7: @implementation MYTarget
jens@7: 
jens@7: 
jens@7: - (id) initWithReceiver: (id)receiver action: (SEL)action
jens@0: {
jens@7:     self = [super init];
jens@7:     if( self ) {
jens@7:         NSMethodSignature *sig = [receiver methodSignatureForSelector: action];
jens@7:         CAssert(sig,@"%@<%p> does not respond to %@",[receiver class],receiver,NSStringFromSelector(action));
jens@7:         CAssert(sig.numberOfArguments==3,
jens@7:                @"-[%@ %@] can't be used as a target because it takes >1 param",
jens@7:                [receiver class],NSStringFromSelector(action));
jens@7:         CAssert(0==strcmp([sig getArgumentTypeAtIndex: 2],"@"),
jens@7:                @"-[%@ %@] can't be used as a target because it takes a non-object param",
jens@7:                [receiver class],NSStringFromSelector(action));
jens@7:         NSInvocation *inv = [NSInvocation invocationWithMethodSignature: sig];
jens@7:         inv.target = receiver;
jens@7:         inv.selector = action;
jens@7:         _invocations = [inv retain];
jens@7:     }
jens@7:     return self;
jens@0: }
jens@0: 
jens@7: + (MYTarget*) targetWithReceiver: (id)receiver action: (SEL)action
jens@7: {
jens@7:     return [[[self alloc] initWithReceiver: receiver action: action] autorelease];
jens@7: }
jens@0: 
jens@7: - (void) dealloc
jens@7: {
jens@7:     [_invocations release];
jens@7:     [super dealloc];
jens@7: }
jens@7: 
jens@7: 
jens@7: - (NSArray*) invocations
jens@7: {
jens@7:     NSMutableArray *invocations = $castIf(NSMutableArray,_invocations);
jens@7:     if( ! invocations )
jens@7:         invocations = [NSMutableArray arrayWithObject: _invocations];
jens@7:     return invocations;
jens@7: }
jens@7: 
jens@7: 
jens@7: - (NSString*) description
jens@7: {
jens@7:     NSMutableString *desc = [NSMutableString stringWithFormat: @"%@{", self.class];
jens@7:     BOOL first = YES;
jens@7:     for( NSInvocation *inv in self.invocations ) {
jens@7:         if( first )
jens@7:             first = NO;
jens@7:         else
jens@7:             [desc appendString: @", "];
jens@7:         [desc appendFormat: @"-[%@ %s]", [inv.target class], inv.selector];
jens@7:     }
jens@7:     [desc appendString: @"}"];
jens@7:     return desc;
jens@7: }
jens@7: 
jens@7: 
jens@7: static BOOL equalInvocations( NSInvocation *a, NSInvocation *b )
jens@7: {
jens@7:     return a.target==b.target && a.selector==b.selector;
jens@7: }
jens@7: 
jens@7: 
jens@7: - (BOOL) isEqual: (MYTarget*)t
jens@7: {
jens@7:     if( ! [t isKindOfClass: [self class]] )
jens@7:         return NO;
jens@7:     if( [_invocations isKindOfClass: [NSInvocation class]] && [t->_invocations isKindOfClass: [NSInvocation class]] )
jens@7:         return equalInvocations(_invocations,t->_invocations);
jens@7:     NSArray *myInvocations = self.invocations, *itsInvocations = t.invocations;
jens@7:     unsigned n = myInvocations.count;
jens@7:     if( n != itsInvocations.count )
jens@7:         return NO;
jens@7:     for( int i=0; i<n; i++ )
jens@7:         if( ! equalInvocations( [myInvocations objectAtIndex: i],
jens@7:                                 [itsInvocations objectAtIndex: i] ) )
jens@7:             return NO;
jens@7:     return YES;
jens@7: }
jens@7: 
jens@7: 
jens@7: - (void) addTarget: (MYTarget*)target
jens@7: {
jens@7:     setObj(&_invocations,[self invocations]);
jens@7:     [_invocations addObjectsFromArray: target.invocations];
jens@7: }
jens@7: 
jens@7: 
jens@7: static id invokeSingleTarget( NSInvocation *invocation, id param )
jens@0: {
jens@1:     id result = nil;
jens@7:     if( invocation && invocation.target ) {
jens@7:         [invocation retain];
jens@1:         @try{
jens@7:             [invocation setArgument: &param atIndex: 2];
jens@7:             [invocation invoke];
jens@1:             
jens@7:             NSMethodSignature *sig = invocation.methodSignature;
jens@1:             NSUInteger returnLength = sig.methodReturnLength;
jens@1:             if( returnLength==0 ) {
jens@1:                 result = nil; // void
jens@0:             } else {
jens@1:                 const char *returnType = sig.methodReturnType;
jens@1:                 if( returnType[0]=='@' ) {
jens@7:                     [invocation getReturnValue: &result];
jens@1:                 } else {
jens@1:                     UInt8 returnBuffer[returnLength];
jens@7:                     [invocation getReturnValue: &returnBuffer];
jens@1:                     result = [NSValue valueWithBytes: &returnBuffer objCType: returnType];
jens@1:                 }
jens@0:             }
jens@1:         }@finally{
jens@7:             [invocation release];
jens@0:         }
jens@1:     }
jens@1:     return result;
jens@0: }
jens@7: 
jens@7: 
jens@7: - (id) invokeWithSender: (id)sender
jens@7: {
jens@7:     id result;
jens@7:     NSMutableArray *invocations = $castIf(NSMutableArray,_invocations);
jens@7:     if( invocations ) {
jens@8:         result = nil;
jens@7:         for( NSInvocation *invocation in invocations )
jens@7:             result = invokeSingleTarget(invocation,sender);
jens@7:     } else {
jens@7:         result = invokeSingleTarget(_invocations,sender);
jens@7:     }
jens@7:     return result;
jens@7: }
jens@7: 
jens@7: 
jens@7: @end