/*

Copyright (C) 2015 Apple Inc. All Rights Reserved.

See LICENSE.txt for this sample’s licensing information

Abstract:

Encapsulates the collection of elements and returns them in presorted states.

*/

@interface PeriodicElements : NSObject

@property (nonatomic, strong) NSMutableDictionary *statesDictionary;

@property (nonatomic, strong) NSMutableDictionary *elementsDictionary;

@property (nonatomic, strong) NSMutableDictionary *nameIndexesDictionary;

@property (nonatomic, strong) NSArray *elementNameIndexArray;

@property (nonatomic, strong) NSArray *elementsSortedByNumber;

@property (nonatomic, strong) NSArray *elementsSortedBySymbol;

@property (nonatomic, strong) NSArray *elementPhysicalStatesArray;

+ (PeriodicElements*)sharedPeriodicElements;

- (NSArray *)elementsWithPhysicalState:(NSString*)aState;

- (NSArray *)elementsWithInitialLetter:(NSString*)aKey;

@end