NetNewsWire/Parser/Sources/ObjC/RSHTMLMetadata.m

484 lines
12 KiB
Objective-C
Executable File

//
// RSHTMLMetadata.m
// RSParser
//
// Created by Brent Simmons on 3/6/16.
// Copyright © 2016 Ranchero Software, LLC. All rights reserved.
//
#import "RSHTMLMetadata.h"
#import "RSParserInternal.h"
#import "RSHTMLTag.h"
static NSString *urlStringFromDictionary(NSDictionary *d);
static NSString *absoluteURLStringWithRelativeURLString(NSString *relativeURLString, NSString *baseURLString);
static NSString *absoluteURLStringWithDictionary(NSDictionary *d, NSString *baseURLString);
static NSArray *objectsOfClassWithTags(Class class, NSArray *tags, NSString *baseURLString);
static NSString *relValue(NSDictionary *d);
static BOOL typeIsFeedType(NSString *type);
static NSString *kIconRelValue = @"icon";
static NSString *kHrefKey = @"href";
static NSString *kSrcKey = @"src";
static NSString *kAppleTouchIconValue = @"apple-touch-icon";
static NSString *kAppleTouchIconPrecomposedValue = @"apple-touch-icon-precomposed";
static NSString *kSizesKey = @"sizes";
static NSString *kTitleKey = @"title";
static NSString *kRelKey = @"rel";
static NSString *kAlternateKey = @"alternate";
static NSString *kRSSSuffix = @"/rss+xml";
static NSString *kAtomSuffix = @"/atom+xml";
static NSString *kJSONSuffix = @"/json";
static NSString *kTypeKey = @"type";
@interface RSHTMLMetadataAppleTouchIcon ()
- (instancetype)initWithTag:(RSHTMLTag *)tag baseURLString:(NSString *)baseURLString;
@end
@interface RSHTMLMetadataFeedLink ()
- (instancetype)initWithTag:(RSHTMLTag *)tag baseURLString:(NSString *)baseURLString;
@end
@interface RSHTMLMetadataFavicon ()
- (instancetype)initWithTag:(RSHTMLTag *)tag baseURLString:(NSString *)baseURLString;
@end
@implementation RSHTMLMetadata
#pragma mark - Init
- (instancetype)initWithURLString:(NSString *)urlString tags:(NSArray <RSHTMLTag *> *)tags {
self = [super init];
if (!self) {
return nil;
}
_baseURLString = urlString;
_tags = tags;
_favicons = [self resolvedFaviconLinks];
NSArray *appleTouchIconTags = [self appleTouchIconTags];
_appleTouchIcons = objectsOfClassWithTags([RSHTMLMetadataAppleTouchIcon class], appleTouchIconTags, urlString);
NSArray *feedLinkTags = [self feedLinkTags];
_feedLinks = objectsOfClassWithTags([RSHTMLMetadataFeedLink class], feedLinkTags, urlString);
_openGraphProperties = [[RSHTMLOpenGraphProperties alloc] initWithURLString:urlString tags:tags];
_twitterProperties = [[RSHTMLTwitterProperties alloc] initWithURLString:urlString tags:tags];
return self;
}
#pragma mark - Private
- (NSArray<RSHTMLTag *> *)linkTagsWithMatchingRel:(NSString *)valueToMatch {
// Case-insensitive; matches a whitespace-delimited word
NSMutableArray<RSHTMLTag *> *tags = [NSMutableArray array];
for (RSHTMLTag *tag in self.tags) {
if (tag.type != RSHTMLTagTypeLink || RSParserStringIsEmpty(urlStringFromDictionary(tag.attributes))) {
continue;
}
NSString *oneRelValue = relValue(tag.attributes);
if (oneRelValue) {
NSArray *relValues = [oneRelValue componentsSeparatedByCharactersInSet:NSCharacterSet.whitespaceAndNewlineCharacterSet];
for (NSString *relValue in relValues) {
if ([relValue compare:valueToMatch options:NSCaseInsensitiveSearch] == NSOrderedSame) {
[tags addObject:tag];
break;
}
}
}
}
return tags;
}
- (NSArray<RSHTMLTag *> *)appleTouchIconTags {
NSMutableArray *tags = [NSMutableArray new];
for (RSHTMLTag *tag in self.tags) {
if (tag.type != RSHTMLTagTypeLink) {
continue;
}
NSString *oneRelValue = relValue(tag.attributes).lowercaseString;
if ([oneRelValue isEqualToString:kAppleTouchIconValue] || [oneRelValue isEqualToString:kAppleTouchIconPrecomposedValue]) {
[tags addObject:tag];
}
}
return tags;
}
- (NSArray<RSHTMLTag *> *)feedLinkTags {
NSMutableArray *tags = [NSMutableArray new];
for (RSHTMLTag *tag in self.tags) {
if (tag.type != RSHTMLTagTypeLink) {
continue;
}
NSDictionary *oneDictionary = tag.attributes;
NSString *oneRelValue = relValue(oneDictionary).lowercaseString;
if (![oneRelValue isEqualToString:kAlternateKey]) {
continue;
}
NSString *oneType = [oneDictionary rsparser_objectForCaseInsensitiveKey:kTypeKey];
if (!typeIsFeedType(oneType)) {
continue;
}
if (RSParserStringIsEmpty(urlStringFromDictionary(oneDictionary))) {
continue;
}
[tags addObject:tag];
}
return tags;
}
- (NSArray<NSString *> *)faviconLinks {
NSMutableArray *urls = [NSMutableArray array];
for (RSHTMLMetadataFavicon *favicon in self.favicons) {
[urls addObject:favicon.urlString];
}
return urls;
}
- (NSArray<RSHTMLMetadataFavicon *> *)resolvedFaviconLinks {
NSArray<RSHTMLTag *> *tags = [self linkTagsWithMatchingRel:kIconRelValue];
NSMutableArray *links = [NSMutableArray array];
NSMutableSet<NSString *> *seenHrefs = [NSMutableSet setWithCapacity:tags.count];
for (RSHTMLTag *tag in tags) {
RSHTMLMetadataFavicon *link = [[RSHTMLMetadataFavicon alloc] initWithTag:tag baseURLString:self.baseURLString];
NSString *urlString = link.urlString;
if (urlString == nil) {
continue;
}
if (![seenHrefs containsObject:urlString]) {
[links addObject:link];
[seenHrefs addObject:urlString];
}
}
return links;
}
@end
static NSString *relValue(NSDictionary *d) {
return [d rsparser_objectForCaseInsensitiveKey:kRelKey];
}
static NSString *urlStringFromDictionary(NSDictionary *d) {
NSString *urlString = [d rsparser_objectForCaseInsensitiveKey:kHrefKey];
if (urlString) {
return urlString;
}
return [d rsparser_objectForCaseInsensitiveKey:kSrcKey];
}
static NSString *absoluteURLStringWithRelativeURLString(NSString *relativeURLString, NSString *baseURLString) {
NSURL *url = [NSURL URLWithString:baseURLString];
if (!url) {
return nil;
}
NSURL *absoluteURL = [NSURL URLWithString:relativeURLString relativeToURL:url];
return absoluteURL.absoluteURL.standardizedURL.absoluteString;
}
static NSString *absoluteURLStringWithDictionary(NSDictionary *d, NSString *baseURLString) {
NSString *urlString = urlStringFromDictionary(d);
if (RSParserStringIsEmpty(urlString)) {
return nil;
}
return absoluteURLStringWithRelativeURLString(urlString, baseURLString);
}
static NSArray *objectsOfClassWithTags(Class class, NSArray *tags, NSString *baseURLString) {
NSMutableArray *objects = [NSMutableArray new];
for (RSHTMLTag *tag in tags) {
id oneObject = [[class alloc] initWithTag:tag baseURLString:baseURLString];
if (oneObject) {
[objects addObject:oneObject];
}
}
return objects;
}
static BOOL typeIsFeedType(NSString *type) {
type = type.lowercaseString;
return [type hasSuffix:kRSSSuffix] || [type hasSuffix:kAtomSuffix] || [type hasSuffix:kJSONSuffix];
}
@implementation RSHTMLMetadataAppleTouchIcon
- (instancetype)initWithTag:(RSHTMLTag *)tag baseURLString:(NSString *)baseURLString {
self = [super init];
if (!self) {
return nil;
}
NSDictionary *d = tag.attributes;
_urlString = absoluteURLStringWithDictionary(d, baseURLString);
_sizes = [d rsparser_objectForCaseInsensitiveKey:kSizesKey];
_rel = [d rsparser_objectForCaseInsensitiveKey:kRelKey];
_size = CGSizeZero;
if (_sizes) {
NSArray *components = [_sizes componentsSeparatedByString:@"x"];
if (components.count == 2) {
CGFloat width = [components[0] floatValue];
CGFloat height = [components[1] floatValue];
_size = CGSizeMake(width, height);
}
}
return self;
}
@end
@implementation RSHTMLMetadataFeedLink
- (instancetype)initWithTag:(RSHTMLTag *)tag baseURLString:(NSString *)baseURLString {
self = [super init];
if (!self) {
return nil;
}
NSDictionary *d = tag.attributes;
_urlString = absoluteURLStringWithDictionary(d, baseURLString);
_title = [d rsparser_objectForCaseInsensitiveKey:kTitleKey];
_type = [d rsparser_objectForCaseInsensitiveKey:kTypeKey];
return self;
}
@end
@implementation RSHTMLMetadataFavicon
- (instancetype)initWithTag:(RSHTMLTag *)tag baseURLString:(NSString *)baseURLString {
self = [super init];
if (!self) {
return nil;
}
NSDictionary *d = tag.attributes;
_urlString = absoluteURLStringWithDictionary(d, baseURLString);
_type = [d rsparser_objectForCaseInsensitiveKey:kTypeKey];
return self;
}
@end
@interface RSHTMLOpenGraphImage ()
@property (nonatomic, readwrite) NSString *url;
@property (nonatomic, readwrite) NSString *secureURL;
@property (nonatomic, readwrite) NSString *mimeType;
@property (nonatomic, readwrite) CGFloat width;
@property (nonatomic, readwrite) CGFloat height;
@property (nonatomic, readwrite) NSString *altText;
@end
@implementation RSHTMLOpenGraphImage
@end
@interface RSHTMLOpenGraphProperties ()
@property (nonatomic) NSMutableArray *ogImages;
@end
@implementation RSHTMLOpenGraphProperties
- (instancetype)initWithURLString:(NSString *)urlString tags:(NSArray <RSHTMLTag *> *)tags {
self = [super init];
if (!self) {
return nil;
}
_ogImages = [NSMutableArray new];
[self parseTags:tags];
return self;
}
- (RSHTMLOpenGraphImage *)currentImage {
return self.ogImages.lastObject;
}
- (RSHTMLOpenGraphImage *)pushImage {
RSHTMLOpenGraphImage *image = [RSHTMLOpenGraphImage new];
[self.ogImages addObject:image];
return image;
}
- (RSHTMLOpenGraphImage *)ensureImage {
RSHTMLOpenGraphImage *image = [self currentImage];
if (image != nil) {
return image;
}
return [self pushImage];
}
- (NSArray *)images {
return self.ogImages;
}
static NSString *ogPrefix = @"og:";
static NSString *ogImage = @"og:image";
static NSString *ogImageURL = @"og:image:url";
static NSString *ogImageSecureURL = @"og:image:secure_url";
static NSString *ogImageType = @"og:image:type";
static NSString *ogImageWidth = @"og:image:width";
static NSString *ogImageHeight = @"og:image:height";
static NSString *ogImageAlt = @"og:image:alt";
static NSString *ogPropertyKey = @"property";
static NSString *ogContentKey = @"content";
- (void)parseTags:(NSArray *)tags {
for (RSHTMLTag *tag in tags) {
if (tag.type != RSHTMLTagTypeMeta) {
continue;
}
NSString *propertyName = tag.attributes[ogPropertyKey];
if (!propertyName || ![propertyName hasPrefix:ogPrefix]) {
continue;
}
NSString *content = tag.attributes[ogContentKey];
if (!content) {
continue;
}
if ([propertyName isEqualToString:ogImage]) {
RSHTMLOpenGraphImage *image = [self currentImage];
if (!image || image.url) { // Most likely case, since og:image will probably appear before other image attributes.
image = [self pushImage];
}
image.url = content;
}
else if ([propertyName isEqualToString:ogImageURL]) {
[self ensureImage].url = content;
}
else if ([propertyName isEqualToString:ogImageSecureURL]) {
[self ensureImage].secureURL = content;
}
else if ([propertyName isEqualToString:ogImageType]) {
[self ensureImage].mimeType = content;
}
else if ([propertyName isEqualToString:ogImageAlt]) {
[self ensureImage].altText = content;
}
else if ([propertyName isEqualToString:ogImageWidth]) {
[self ensureImage].width = [content floatValue];
}
else if ([propertyName isEqualToString:ogImageHeight]) {
[self ensureImage].height = [content floatValue];
}
}
}
@end
@implementation RSHTMLTwitterProperties
static NSString *twitterNameKey = @"name";
static NSString *twitterContentKey = @"content";
static NSString *twitterImageSrc = @"twitter:image:src";
- (instancetype)initWithURLString:(NSString *)urlString tags:(NSArray <RSHTMLTag *> *)tags {
self = [super init];
if (!self) {
return nil;
}
for (RSHTMLTag *tag in tags) {
if (tag.type != RSHTMLTagTypeMeta) {
continue;
}
NSString *name = tag.attributes[twitterNameKey];
if (!name || ![name isEqualToString:twitterImageSrc]) {
continue;
}
NSString *content = tag.attributes[twitterContentKey];
if (!content || content.length < 1) {
continue;
}
_imageURL = content;
break;
}
return self;
}
@end