1/******************************************************************************
2 * $Id$
3 *
4 * Copyright (c) 2011-2012 Transmission authors and contributors
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 * DEALINGS IN THE SOFTWARE.
23 *****************************************************************************/
24
25#import "NSMutableArrayAdditions.h"
26
27@implementation NSMutableArray (NSMutableArrayAdditions)
28
29/*
30 Note: This assumes Apple implemented this as an array under the hood.
31 If the underlying data structure is a linked-list, for example, then this might be less
32 efficient than simply removing the object and re-adding it.
33 */
34- (void) moveObjectAtIndex: (NSUInteger) fromIndex toIndex: (NSUInteger) toIndex
35{
36    if (fromIndex == toIndex)
37        return;
38    
39    id object = [[self objectAtIndex: fromIndex] retain];
40    
41    //shift objects - more efficient than simply removing the object and re-inserting the object
42    if (fromIndex < toIndex)
43    {
44        for (NSUInteger i = fromIndex; i < toIndex; ++i)
45            [self replaceObjectAtIndex: i withObject: [self objectAtIndex: i+1]];
46    }
47    else
48    {
49        for (NSUInteger i = fromIndex; i > toIndex; --i)
50            [self replaceObjectAtIndex: i withObject: [self objectAtIndex: i-1]];
51    }
52    [self replaceObjectAtIndex: toIndex withObject: object];
53    
54    [object release];
55}
56
57@end
58