#import "NSArray+utils.h"
#import <UIKit/UIKit.h>

@implementation NSArray (utils)

- (NSArray *)intersect:(NSArray *)array withPropertyName:(NSString *)propertyName {
    NSMutableArray* intersection = [NSMutableArray new];
    for (NSObject* object in array) {
        NSArray* filteredArray = [self filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"%@ == %@", propertyName, object]];
        [intersection addObjectsFromArray:filteredArray];
    }
    
    return [NSArray arrayWithArray:intersection];
}

- (NSArray *)difference:(NSArray *)array withPropertyName:(NSString *)propertyName {
    NSMutableArray* diff = [NSMutableArray arrayWithArray:self];
    NSArray* intersection = [self intersect:array withPropertyName:propertyName];
    [diff removeObjectsInArray:intersection];
    
    return [NSArray arrayWithArray:diff];
}

- (NSArray *)mapObjectsUsingBlock:(id (^)(id obj, NSUInteger idx))block {
    NSMutableArray *result = [NSMutableArray arrayWithCapacity:[self count]];
    [self enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
        [result addObject:block(obj, idx)];
    }];
    return result;
}

- (NSArray *)sortByPropertyName:(NSString *)propertyName {
    return [self sortedArrayUsingComparator:^NSComparisonResult(id a, id b) {
        id first = [a valueForKey:propertyName];
        id second = [b valueForKey:propertyName];
        return [first compare:second];
    }];
}

@end