inbetweenranges.m

- (NSArray *)inbetweenRangesForArrayOfRanges:(NSArray *)arrayOfRanges forString:(NSString *)string
{
    NSMutableArray *ranges = @[].mutableCopy;
    
    for (int i = 0; i < arrayOfRanges.count; i++)
    {
        // grab the first range
        NSRange currentRange = [arrayOfRanges[i] rangeValue];
        
        // add it to our return object
        [ranges addObject:[NSValue valueWithRange:currentRange]];
        
        // if the first range starts at 0, or if the length of the range is the entire string, bail out
        if (currentRange.location != 0 || currentRange.length == string.length)
        {
            
            if (i == 0) // first URL starts later in the string
            {
                // Make the range up in between loc 0 and the start of the first range
                NSRange newRange = NSMakeRange(0, currentRange.location - 1);
                [ranges addObject:[NSValue valueWithRange:newRange]];
            }
            else // otherwise lets get going
            {
                NSRange previousRange = [arrayOfRanges[i - 1] rangeValue];
                NSUInteger index = (previousRange.location + 1) + previousRange.length;
                NSUInteger length = currentRange.location - (previousRange.length + 1);
                NSRange newRange = NSMakeRange(index, length);
                [ranges addObject:[NSValue valueWithRange:newRange]];
            }
        }
    }
    
    return ranges;
}