Add implementation for a DOM Token List

https://dom.spec.whatwg.org/#interface-domtokenlist

HTMLKit/HTMLDOMTokenList.m

@@ -0,0 +1,109 @@
+//
+//  HTMLDOMTokenList.m
+//  HTMLKit
+//
+//  Created by Iska on 30/11/15.
+//  Copyright © 2015 BrainCookie. All rights reserved.
+//
+
+#import "HTMLDOMTokenList.h"
+#import "HTMLElement.h"
+
+@interface HTMLDOMTokenList ()
+{
+	HTMLElement *_element;
+	NSString *_attribute;
+	NSMutableOrderedSet *_tokens;
+}
+@end
+
+@implementation HTMLDOMTokenList
+@synthesize element = _element;
+@synthesize attribute = _attribute;
+
+#pragma mark - Init
+
+- (instancetype)initWithElement:(HTMLElement *)element attribute:(NSString *)attribute value:(NSString *)value
+{
+	self = [super init];
+	if (self) {
+		_element = element;
+		_attribute = [attribute copy];
+		_tokens = [NSMutableOrderedSet new];
+		[self add:[value componentsSeparatedByString:@" "]];
+	}
+	return self;
+}
+
+#pragma mark - Access
+
+- (void)updateValue
+{
+	_element[_attribute] = self.stringify;
+}
+
+- (NSUInteger)length
+{
+	return _tokens.count;
+}
+
+- (BOOL)contains:(NSString *)token
+{
+	return [_tokens containsObject:token];
+}
+
+- (void)add:(NSArray<NSString *> *)tokens
+{
+	for (NSString *token in tokens) {
+		if (![token isEqualToString:@""]) {
+			[_tokens addObject:token];
+		}
+	}
+	[self updateValue];
+}
+
+- (void)remove:(NSArray<NSString *> *)tokens
+{
+	for (NSString *token in tokens) {
+		[_tokens removeObject:token];
+	}
+	[self updateValue];
+}
+
+- (BOOL)toggle:(NSString *)token
+{
+	if ([_tokens containsObject:token]) {
+		[_tokens removeObject:token];
+		[self updateValue];
+		return NO;
+	} else {
+		[_tokens addObject:token];
+		[self updateValue];
+		return YES;
+	}
+}
+
+- (void)replaceToke:(NSString *)token withToken:(NSString *)newToken
+{
+	NSUInteger index = [_tokens indexOfObject:token];
+	_tokens[index] = newToken;
+	[self updateValue];
+}
+
+- (NSString *)objectAtIndexedSubscript:(NSUInteger)index
+{
+	return _tokens[index];
+}
+
+- (void)setObject:(NSString *)obj atIndexedSubscript:(NSUInteger)index
+{
+	_tokens[index] = obj;
+	[self updateValue];
+}
+
+- (NSString *)stringify
+{
+	return [_tokens.array componentsJoinedByString:@" "];
+}
+
+@end