codility01.m

#import <Foundation/Foundation.h>

NSString *testString = @"00:01:07,400-234-090\n00:05:01,701-080-080\n00:05:00,400-234-090";

NSTimeInterval durationToSeconds(NSString *duration)
{
    NSDateFormatter *df = [NSDateFormatter new];
    df.dateFormat = @"hh:mm:ss";

    NSDate *reference = [df dateFromString:@"00:00:00"];
    NSDate *foox = [df dateFromString:duration];

    NSTimeInterval seconds = [foox timeIntervalSinceDate:reference];

    return seconds;
}

int calculateCostFromDuration(NSTimeInterval duration)
{
    int cost = 0;

    if (duration > (5*60))
    {
        float d = duration/60.0;
        float ceil = ceilf(d);
        cost = ((int)ceil) * 150;
    }
    else
    {
        cost = (int)duration*3;
    }

    return cost;
}

int solution(NSString *S)
{
    int totalCost = 0;

    NSMutableDictionary *lengthByPhoneNumber = [NSMutableDictionary dictionary];
    NSMutableDictionary *costByPhoneNumber = [NSMutableDictionary dictionary];
    NSArray *lines = [S componentsSeparatedByString:@"\n"];

    for(NSString *line in lines)
    {
        NSArray *elements = [line componentsSeparatedByString:@","];
        if (elements.count == 2)
        {
            NSTimeInterval length = durationToSeconds(elements[0]);
            NSString *number = elements[1];

            if (lengthByPhoneNumber[number] != nil)
            {
                NSNumber *currentLenght = lengthByPhoneNumber[number];
                length = length + [currentLenght integerValue];
            }
            lengthByPhoneNumber[number] = @((int)length);

            int cost;
            cost = calculateCostFromDuration(length);
            if (costByPhoneNumber[number] != nil)
            {
                NSNumber *costNumber = costByPhoneNumber[number];
                cost = cost + [costNumber intValue];
            }
            costByPhoneNumber[number] = @(cost);
        }
    }

    // find longest call number
    NSString *longestCallNumber;
    int longestCallValue = 0;
    for(NSString *number in [lengthByPhoneNumber allKeys])
    {
        NSNumber *lenghtNumber = lengthByPhoneNumber[number];
        if ([lenghtNumber intValue] > longestCallValue)
        {
            longestCallNumber = number;
            longestCallValue = [lenghtNumber intValue];
        }
    }

    if (lengthByPhoneNumber.count > 1 && longestCallNumber != nil)
    {
        [lengthByPhoneNumber removeObjectForKey:longestCallNumber];
        [costByPhoneNumber removeObjectForKey:longestCallNumber];
    }

    // add cost of all bar last element in the array
    for(NSString *number in [costByPhoneNumber allKeys])
    {
        NSNumber *cost = costByPhoneNumber[number];
        totalCost = totalCost + [cost intValue];
    }

    return totalCost;
}