Reorganized File Structure

Added Documentation

MathKit/NSIndexPath+MPAdditions.m

@@ -0,0 +1,117 @@
+//
+//  NSIndexPath+MPRemoveFirstIndex.m
+//  MathPad
+//
+//  Created by Kim Wittenburg on 23.04.14.
+//  Copyright (c) 2014 Kim Wittenburg. All rights reserved.
+//
+
+#import "NSIndexPath+MPAdditions.h"
+
+
+
+@implementation NSIndexPath (MPAdditions)
+
+
+- (NSUInteger)firstIndex
+{
+    return [self indexAtPosition:0];
+}
+
+
+- (NSUInteger)lastIndex
+{
+    return [self indexAtPosition:self.length-1];
+}
+
+
+- (NSIndexPath *)indexPathByReplacingLastIndexWithIndex:(NSUInteger)index
+{
+    return [[self indexPathByRemovingLastIndex] indexPathByAddingIndex:index];
+}
+
+
+- (NSIndexPath *)indexPathByRemovingFirstIndex
+{
+    if (self.length <= 1) {
+        return [[NSIndexPath alloc] init];
+    }
+    NSUInteger indexes[self.length];
+    [self getIndexes:indexes];
+    NSUInteger newIndexes[self.length-1];
+    for (NSUInteger i = 0; i < self.length-1; i++) {
+        newIndexes[i] = indexes[i+1];
+    }
+    return [[NSIndexPath alloc] initWithIndexes:newIndexes length:self.length-1];
+}
+
+
+- (NSIndexPath *)indexPathByPreceedingIndex:(NSUInteger)index
+{
+    NSUInteger newIndexes[self.length+1];
+    newIndexes[0] = index;
+    for (NSUInteger i = 0; i < self.length; i++) {
+        newIndexes[i+1] = [self indexAtPosition:i];
+    }
+    return [[NSIndexPath alloc] initWithIndexes:newIndexes length:self.length+1];
+}
+
+
+- (NSIndexPath *)indexPathByIncrementingLastIndex
+{
+    if (self.length < 1) {
+        return [[NSIndexPath alloc] init];
+    }
+    NSUInteger lastIndex = [self lastIndex];
+    lastIndex++;
+    return [[self indexPathByRemovingLastIndex] indexPathByAddingIndex:lastIndex];
+}
+
+- (NSIndexPath *)indexPathByDecrementingLastIndex
+{
+    if (self.length < 1) {
+        return [[NSIndexPath alloc] init];
+    }
+    NSUInteger lastIndex = [self lastIndex];
+    lastIndex--;
+    return [[self indexPathByRemovingLastIndex] indexPathByAddingIndex:lastIndex];
+}
+
+
+- (NSIndexPath *)indexPathByRemovingIndexesFrom:(NSUInteger)from
+{
+    NSIndexPath *indexPath = [[NSIndexPath alloc] init];
+    for (NSUInteger position = 0; position < MIN(from, self.length); position++) {
+        indexPath = [indexPath indexPathByAddingIndex:[self indexAtPosition:position]];
+    }
+    return indexPath;
+}
+
+
+- (NSIndexPath *)indexPathByRemovingIndexesTo:(NSUInteger)to
+{
+    NSIndexPath *indexPath = [[NSIndexPath alloc] init];
+    for (NSUInteger position = to; position < self.length; position++) {
+        indexPath = [indexPath indexPathByAddingIndex:[self indexAtPosition:position]];
+    }
+    return indexPath;
+}
+
+
+- (NSIndexPath *)commonIndexPathWith:(NSIndexPath *)indexPath
+{
+    NSIndexPath *commonPath = [[NSIndexPath alloc] init];
+    NSUInteger length = MIN(self.length, indexPath.length);
+    for (NSUInteger position = 0; position < length; position++) {
+        NSUInteger selfIndex = [self indexAtPosition:position];
+        NSUInteger otherIndex = [indexPath indexAtPosition:position];
+        if (selfIndex == otherIndex) {
+            commonPath = [commonPath indexPathByAddingIndex:selfIndex];
+        } else {
+            break;
+        }
+    }
+    return commonPath;
+}
+
+@end