NSArrayAdditions.m

/*
 * Created by Mayur Pawashe on 12/31/12.
 *
 * Copyright (c) 2012 zgcoder
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * Neither the name of the project's author nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#import "NSArrayAdditions.h"

@implementation NSArray (NSArrayAdditions)

- (NSArray *)zgFilterUsingBlock:(zg_array_filter_t)shouldFilter
{
	NSMutableArray *newResults = [[NSMutableArray alloc] init];
	
	for (id item in self)
	{
		if (!shouldFilter(item))
		{
			[newResults addObject:item];
		}
	}
	
	return [NSArray arrayWithArray:newResults];
}

// our's first, their's later
- (id)zgBinarySearchUsingBlock:(zg_binary_search_t)comparator
{
	CFArrayRef selfReference = (__bridge CFArrayRef)(self);
	id __unsafe_unretained targetObject = nil;
	
	if (self.count > 0)
	{
		NSUInteger maxIndex = self.count - 1;
		NSUInteger minIndex = 0;
		while (maxIndex >= minIndex)
		{
			NSUInteger middleIndex = (minIndex + maxIndex) / 2;
			id __unsafe_unretained object = CFArrayGetValueAtIndex(selfReference, middleIndex);
			
			switch (comparator(object))
			{
				case NSOrderedAscending:
					minIndex = middleIndex + 1;
					break;
				case NSOrderedDescending:
					if (middleIndex == 0) goto ZG_BINARY_SEARCH_FINISHED;
					maxIndex = middleIndex - 1;
					break;
				case NSOrderedSame:
					targetObject = object;
					goto ZG_BINARY_SEARCH_FINISHED;
			}
		}
	}
	
ZG_BINARY_SEARCH_FINISHED:
	
	return targetObject;
}

@end