MWFeedParser.m

//
//  MWFeedParser.m
//  MWFeedParser
//
//  Copyright (c) 2010 Michael Waterfall
//  
//  Permission is hereby granted, free of charge, to any person obtaining a copy
//  of this software and associated documentation files (the "Software"), to deal
//  in the Software without restriction, including without limitation the rights
//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
//  copies of the Software, and to permit persons to whom the Software is
//  furnished to do so, subject to the following conditions:
//  
//  1. The above copyright notice and this permission notice shall be included
//     in all copies or substantial portions of the Software.
//  
//  2. This Software cannot be used to archive or collect data such as (but not
//     limited to) that of events, news, experiences and activities, for the 
//     purpose of any concept relating to diary/journal keeping.
//  
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
//  THE SOFTWARE.
//

#import "MWFeedParser.h"
#import "MWFeedParser_Private.h"
#import "NSString+MW_HTML.h"
#import "NSDate+InternetDateTime.h"

// NSXMLParser Logging
#if 0 // Set to 1 to enable XML parsing logs
#define MWXMLLog(x, ...) NSLog(x, ## __VA_ARGS__);
#else
#define MWXMLLog(x, ...)
#endif

// Empty XHTML elements ( <!ELEMENT br EMPTY> in https://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd )
#define ELEMENT_IS_EMPTY(e) ([e isEqualToString:@"br"] || [e isEqualToString:@"img"] || [e isEqualToString:@"input"] || \
[e isEqualToString:@"hr"] || [e isEqualToString:@"link"] || [e isEqualToString:@"base"] || \
[e isEqualToString:@"basefont"] || [e isEqualToString:@"frame"] || [e isEqualToString:@"meta"] || \
[e isEqualToString:@"area"] || [e isEqualToString:@"col"] || [e isEqualToString:@"param"])

// Implementation
@implementation MWFeedParser

// Properties
@synthesize url, delegate;
@synthesize urlConnection, xmlData, xmlTextEncodingName, connectionType;
@synthesize feedParseType, feedParser, currentPath, currentText, currentElementAttributes, item, info;
@synthesize pathOfElementWithXHTMLType;
@synthesize stopped, failed, parsing;

#pragma mark -
#pragma mark NSObject

- (id)init {
	if ((self = [super init])) {
        
		// Defaults
		feedParseType = ParseTypeFull;
		connectionType = ConnectionTypeSynchronously;
		
		// Date Formatters
		// Good info on internet dates here: https://developer.apple.com/iphone/library/qa/qa2010/qa1480.html
		NSLocale *en_US_POSIX = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"];
		dateFormatterRFC822 = [[NSDateFormatter alloc] init];
		dateFormatterRFC3339 = [[NSDateFormatter alloc] init];
        [dateFormatterRFC822 setLocale:en_US_POSIX];
        [dateFormatterRFC3339 setLocale:en_US_POSIX];
        [dateFormatterRFC822 setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
        [dateFormatterRFC3339 setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
		
	}
	return self;
}

// Initialise with a URL
// Mainly for historic reasons before -parseURL:
- (id)initWithFeedURL:(NSURL *)feedURL {
	if ((self = [self init])) {
		
		// Check if an string was passed as old init asked for NSString not NSURL
		if ([feedURL isKindOfClass:[NSString class]]) {
			feedURL = [NSURL URLWithString:(NSString *)feedURL];
		}
		
		// Remember url
		self.url = feedURL;
		
	}
	return self;
}


- (id)initWithFeedData:(NSData *)data textEncodingName:(NSString *)textEncodingName {
    if ((self = [self init])) {
        connectionType = ConnectionTypeLocalData;
        self.xmlData = [NSMutableData dataWithData:data];
        self.xmlTextEncodingName = textEncodingName;
    }
    return self;
}

#pragma mark -
#pragma mark Parsing

// Reset data variables before processing
// Exclude parse state variables as they are needed after parse
- (void)reset {
	if(connectionType != ConnectionTypeLocalData) {
        self.xmlData = nil;
        self.xmlTextEncodingName = nil;
    }
	self.urlConnection = nil;
	feedType = FeedTypeUnknown;
	self.currentPath = @"/";
	self.currentText = [[NSMutableString alloc] init];
	self.item = nil;
	self.info = nil;
	self.currentElementAttributes = nil;
	parseStructureAsContent = NO;
	self.pathOfElementWithXHTMLType = nil;
	hasEncounteredItems = NO;
}

// Parse using URL for backwards compatibility
- (BOOL)parse {
    
	// Reset
	[self reset];
	
	// Perform checks before parsing
	if (connectionType!=ConnectionTypeLocalData && (!url || !delegate)) { [self parsingFailedWithErrorCode:MWErrorCodeNotInitiated
                                                                                            andDescription:@"Delegate or URL not specified"]; return NO; }
	if (parsing) { [self parsingFailedWithErrorCode:MWErrorCodeGeneral 
									 andDescription:@"Cannot start parsing as parsing is already in progress"]; return NO; }
	
	// Reset state for next parse
	parsing = YES;
	aborted = NO;
	stopped = NO;
	failed = NO;
	parsingComplete = NO;
	
	// Start
	BOOL success = YES;
	
	// Request
	NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:url
                                                                cachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData 
                                                            timeoutInterval:60];
	[request setValue:@"MWFeedParser" forHTTPHeaderField:@"User-Agent"];
	
	// Debug Log
	MWLog(@"MWFeedParser: Connecting & downloading feed data");
	
	// Connection
	if (connectionType == ConnectionTypeAsynchronously) {
		
		// Async
		urlConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
		if (urlConnection) {
			xmlData = [[NSMutableData alloc] init];// Create data
		} else {
			[self parsingFailedWithErrorCode:MWErrorCodeConnectionFailed 
							  andDescription:[NSString stringWithFormat:@"Asynchronous connection failed to URL: %@", url]];
			success = NO;
		}
		
	} else if (connectionType == ConnectionTypeSynchronously) {
        
		// Sync
		NSURLResponse *response = nil;
		NSError *error = nil;
		NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
		if (data && !error) {
			[self startParsingData:data textEncodingName:[response textEncodingName]]; // Process
		} else {
			[self parsingFailedWithErrorCode:MWErrorCodeConnectionFailed 
							  andDescription:[NSString stringWithFormat:@"Synchronous connection failed to URL: %@", url]];
			success = NO;
		}
		
	} else {
        // Local data (no request)
        [self startParsingData:self.xmlData textEncodingName:self.xmlTextEncodingName];
    }
	
	// return
	return success;
	
}

// Begin XML parsing
- (void)startParsingData:(NSData *)data textEncodingName:(NSString *)textEncodingName {
	if (data && !feedParser) {
		
		// Create feed info
		MWFeedInfo *i = [[MWFeedInfo alloc] init];
		self.info = i;
		
		// Check whether it's UTF-8
		if (![[textEncodingName lowercaseString] isEqualToString:@"utf-8"]) {
			
			// Not UTF-8 so convert
			MWLog(@"MWFeedParser: XML document was not UTF-8 so we're converting it");
			NSString *string = nil;
			
			// Attempt to detect encoding from response header
			NSStringEncoding nsEncoding = 0;
			if (textEncodingName) {
				CFStringEncoding cfEncoding = CFStringConvertIANACharSetNameToEncoding((__bridge_retained CFStringRef)textEncodingName);
				if (cfEncoding != kCFStringEncodingInvalidId) {
					nsEncoding = CFStringConvertEncodingToNSStringEncoding(cfEncoding);
					if (nsEncoding != 0) string = [[NSString alloc] initWithData:data encoding:nsEncoding];
				}
			}
			
			// If that failed then make our own attempts
			if (!string) {
				// https://www.mikeash.com/pyblog/friday-qa-2010-02-19-character-encodings.html
				string			    = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
				if (!string) string = [[NSString alloc] initWithData:data encoding:NSISOLatin1StringEncoding];
				if (!string) string = [[NSString alloc] initWithData:data encoding:NSMacOSRomanStringEncoding];
			}
			
			// Nil data
			data = nil;
			
			// Parse
			if (string) {
				
				// Set XML encoding to UTF-8
				if ([string hasPrefix:@"<?xml"]) {
					NSRange a = [string rangeOfString:@"?>"];
					if (a.location != NSNotFound) {
						NSString *xmlDec = [string substringToIndex:a.location];
						if ([xmlDec rangeOfString:@"encoding=\"UTF-8\"" 
										  options:NSCaseInsensitiveSearch].location == NSNotFound) {
							NSRange b = [xmlDec rangeOfString:@"encoding=\""];
							if (b.location != NSNotFound) {
								NSUInteger s = b.location+b.length;
								NSRange c = [xmlDec rangeOfString:@"\"" options:0 range:NSMakeRange(s, [xmlDec length] - s)];
								if (c.location != NSNotFound) {
									NSString *temp = [string stringByReplacingCharactersInRange:NSMakeRange(b.location,c.location+c.length-b.location)
                                                                                     withString:@"encoding=\"UTF-8\""];
									string = temp;
								}
							}
						}
					}
				}
				
				// Convert string to UTF-8 data
				if (string) {
					data = [string dataUsingEncoding:NSUTF8StringEncoding];
				}
				
			}
			
		}
		
		// Create NSXMLParser
		if (data) {
			NSXMLParser *newFeedParser = [[NSXMLParser alloc] initWithData:data];
			self.feedParser = newFeedParser;
			if (feedParser) { 
				
				// Parse!
				feedParser.delegate = self;
				[feedParser setShouldProcessNamespaces:YES];
				[feedParser parse];
				self.feedParser = nil; // Release after parse
				
			} else {
				[self parsingFailedWithErrorCode:MWErrorCodeFeedParsingError andDescription:@"Feed not a valid XML document"];
			}
		} else {
			[self parsingFailedWithErrorCode:MWErrorCodeFeedParsingError andDescription:@"Error with feed encoding"];
		}
        
	}
}

// Abort parsing early if we're ignoring feed items
- (void)abortParsingEarly {
	
	// Abort
	aborted = YES; [feedParser abortParsing];
	[self parsingFinished];
	
}

// Stop parsing
- (void)stopParsing {
	
	// Only if we're parsing
	if (parsing && !parsingComplete) {
		
		// Debug Log
		MWLog(@"MWFeedParser: Parsing stopped");
		
		// Stop
		stopped = YES;
		
		// Stop downloading
		[urlConnection cancel];
		self.urlConnection = nil;
		self.xmlData = nil;
        self.xmlTextEncodingName = nil;
		
		// Abort
		aborted = YES;
		[feedParser abortParsing];
		
		// Finished
		[self parsingFinished];
		
	}
	
}

// Finished parsing document successfully
- (void)parsingFinished {
	
	// Finish
	if (!parsingComplete) {
		
		// Set state and notify delegate
		parsing = NO;
		parsingComplete = YES;
		if ([delegate respondsToSelector:@selector(feedParserDidFinish:)])
			[delegate feedParserDidFinish:self];
		
		// Reset
		[self reset];
		
	}
	
}

// If an error occurs, create NSError and inform delegate
- (void)parsingFailedWithErrorCode:(int)code andDescription:(NSString *)description {
	
	// Finish & create error
	if (!parsingComplete) {
		
		// State
		failed = YES;
		parsing = NO;
		parsingComplete = YES;
		
		// Create error
		NSError *error = [NSError errorWithDomain:MWErrorDomain 
											 code:code 
										 userInfo:[NSDictionary dictionaryWithObject:description
																			  forKey:NSLocalizedDescriptionKey]];
		MWLog(@"%@", error);
		
		// Abort parsing
		if (feedParser) {
			aborted = YES;
			[feedParser abortParsing];
		}
		
		// Reset
		[self reset];
		
		// Inform delegate
		if ([delegate respondsToSelector:@selector(feedParser:didFailWithError:)])
			[delegate feedParser:self didFailWithError:error];
		
	}
	
}

#pragma mark -
#pragma mark NSURLConnection Delegate (Async)

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
	[xmlData setLength:0];
	self.xmlTextEncodingName = [response textEncodingName];
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
	[xmlData appendData:data];
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
	
	// Failed
	self.urlConnection = nil;
	self.xmlData = nil;
    self.xmlTextEncodingName = nil;
	
    // Error
	[self parsingFailedWithErrorCode:MWErrorCodeConnectionFailed andDescription:[error localizedDescription]];
	
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
	
	// Succeed
	MWLog(@"MWFeedParser: Connection successful... received %d bytes of data", [xmlData length]);
	
	// Parse
	if (!stopped) [self startParsingData:xmlData textEncodingName:self.xmlTextEncodingName];
	
    // Cleanup
    self.urlConnection = nil;
    self.xmlData = nil;
	self.xmlTextEncodingName = nil;
    
}

-(NSCachedURLResponse *)connection:(NSURLConnection *)connection willCacheResponse:(NSCachedURLResponse *)cachedResponse {
	return nil; // Don't cache
}

#pragma mark -
#pragma mark XML Parsing

- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI 
 qualifiedName:(NSString *)qualifiedName attributes:(NSDictionary *)attributeDict {
	MWXMLLog(@"NSXMLParser: didStartElement: %@", qualifiedName);
	
	
    @autoreleasepool {
        
        // Adjust path
        self.currentPath = [currentPath stringByAppendingPathComponent:qualifiedName];
        self.currentElementAttributes = attributeDict;
        
        // Parse content as structure (Atom feeds with element type="xhtml")
        // - Use elementName not qualifiedName to ignore XML namespaces for XHTML entities
        if (parseStructureAsContent) {
            
            // Open XHTML tag
            [currentText appendFormat:@"<%@", elementName];
            
            // Add attributes
            for (NSString *key in attributeDict) {
                [currentText appendFormat:@" %@=\"%@\"", key, 
                 [[attributeDict objectForKey:key] stringByEncodingHTMLEntities]];
            }
            
            // End tag or close
            if (ELEMENT_IS_EMPTY(elementName)) {
                [currentText appendFormat:@" />", elementName];
            } else {
                [currentText appendFormat:@">", elementName];
            }
            
            
            return;
            
        }
        
        // Reset
        [self.currentText setString:@""];
        
        // Determine feed type
        if (feedType == FeedTypeUnknown) {
            if ([qualifiedName isEqualToString:@"rss"]) feedType = FeedTypeRSS; 
            else if ([qualifiedName isEqualToString:@"rdf:RDF"]) feedType = FeedTypeRSS1;
            else if ([qualifiedName isEqualToString:@"feed"]) feedType = FeedTypeAtom;
            else {
                
                // Invalid format so fail
                [self parsingFailedWithErrorCode:MWErrorCodeFeedParsingError 
                                  andDescription:@"XML document is not a valid web feed document."];
                
            }
            
            return;
        }
        
        // Entering new feed element
        if (feedParseType != ParseTypeItemsOnly) {
            if ((feedType == FeedTypeRSS  && [currentPath isEqualToString:@"/rss/channel"]) ||
                (feedType == FeedTypeRSS1 && [currentPath isEqualToString:@"/rdf:RDF/channel"]) ||
                (feedType == FeedTypeAtom && [currentPath isEqualToString:@"/feed"])) {
                return;
            }
        }
        
        // Entering new item element
        if ((feedType == FeedTypeRSS  && [currentPath isEqualToString:@"/rss/channel/item"]) ||
            (feedType == FeedTypeRSS1 && [currentPath isEqualToString:@"/rdf:RDF/item"]) ||
            (feedType == FeedTypeAtom && [currentPath isEqualToString:@"/feed/entry"])) {
            
            // Send off feed info to delegate
            if (!hasEncounteredItems) {
                hasEncounteredItems = YES;
                if (feedParseType != ParseTypeItemsOnly) { // Check whether to ignore feed info
                    
                    // Dispatch feed info to delegate
                    [self dispatchFeedInfoToDelegate];
                    
                    // Stop parsing if only requiring meta data
                    if (feedParseType == ParseTypeInfoOnly) {
                        
                        // Debug log
                        MWLog(@"MWFeedParser: Parse type is ParseTypeInfoOnly so finishing here");
                        
                        // Finish
                        [self abortParsingEarly];
                        
                        return;
                        
                    }
                    
                } else {
                    
                    // Ignoring feed info so debug log
                    MWLog(@"MWFeedParser: Parse type is ParseTypeItemsOnly so ignoring feed info");
                    
                }
            }
            
            // New item
            MWFeedItem *newItem = [[MWFeedItem alloc] init];
            self.item = newItem;
            
            
            
            // Return
            return;
            
        }
        
        // Check if entering into an Atom content tag with type "xhtml"
        // If type is "xhtml" then it can contain child elements and structure needs
        // to be parsed as content
        // See: https://www.atomenabled.org/developers/syndication/atom-format-spec.php#rfc.section.3.1.1
        if (feedType == FeedTypeAtom) {
            
            // Check type attribute
            NSString *typeAttribute = [attributeDict objectForKey:@"type"];
            if (typeAttribute && [typeAttribute isEqualToString:@"xhtml"]) {
                
                // Start parsing structure as content
                parseStructureAsContent = YES;
                
                // Remember path so we can stop parsing structure when element ends
                self.pathOfElementWithXHTMLType = currentPath;
                
            }
            
        }
        
        
    }
	
}

- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName 
  namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName {
	MWXMLLog(@"NSXMLParser: didEndElement: %@", qName);
	
	
    @autoreleasepool {
        
        // Parse content as structure (Atom feeds with element type="xhtml")
        // - Use elementName not qualifiedName to ignore XML namespaces for XHTML entities
        if (parseStructureAsContent) {
            
            // Check for finishing parsing structure as content
            if (currentPath.length > pathOfElementWithXHTMLType.length) {
                
                // Close XHTML tag unless it is an empty element
                if (!ELEMENT_IS_EMPTY(elementName)) [currentText appendFormat:@"</%@>", elementName];
                
                // Adjust path & don't continue
                self.currentPath = [currentPath stringByDeletingLastPathComponent];
                
                // Return
                return;
                
            }
            
            // Finish
            parseStructureAsContent = NO;
            self.pathOfElementWithXHTMLType = nil;
            
            // Continue...
            
        }
        
        // Store data
        BOOL processed = NO;
        if (currentText) {
            NSString *processedText = nil;
            if (![elementName hasSuffix:@"summary"] && ![elementName hasSuffix:@"content"]){
                // Remove newlines and whitespace from currentText if its not the rich text of the summary
               processedText = [currentText stringByRemovingNewLinesAndWhitespace]; 
            } else {
                processedText = currentText;
            }
            
            // Process
            switch (feedType) {
                case FeedTypeRSS: {
                    
                    // Item
                    if (!processed) {
                        if ([currentPath isEqualToString:@"/rss/channel/item/title"]) { if (processedText.length > 0) item.title = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/link"]) { if (processedText.length > 0) item.link = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/guid"]) { if (processedText.length > 0) item.identifier = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/description"]) { if (processedText.length > 0 && item.summary == nil) item.summary = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/content:encoded"]) { if (processedText.length > 0) item.content = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/pubDate"]) { if (processedText.length > 0) item.date = [NSDate dateFromInternetDateTimeString:processedText formatHint:DateFormatHintRFC822]; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/enclosure"]) { [self createEnclosureFromAttributes:currentElementAttributes andAddToItem:item]; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/dc:date"]) { if (processedText.length > 0) item.date = [NSDate dateFromInternetDateTimeString:processedText formatHint:DateFormatHintRFC3339]; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/itunes:image"]) {
                            if ([currentElementAttributes valueForKey:@"href"]) item.imageURL = [currentElementAttributes valueForKey:@"href"]; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/itunes:duration"]) {
                            if (processedText.length > 0) item.duration =  processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/item/itunes:summary"]) {
                            if (processedText.length > 0) item.summary =  processedText; processed = YES; }
                    }
                    
                    // Info
                    if (!processed && feedParseType != ParseTypeItemsOnly) {
                        if ([currentPath isEqualToString:@"/rss/channel/title"]) { if (processedText.length > 0) info.title = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/description"]) { if (processedText.length > 0) info.summary = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/link"]) { if (processedText.length > 0) info.link = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/itunes:image"]) {

                            NSLog(@"Found feed  image");
                            if ([currentElementAttributes valueForKey:@"href"]) {
                                
                                info.imageURL = [currentElementAttributes valueForKey:@"href"]; processed = YES; }   
                            
                            }
                        else if ([currentPath isEqualToString:@"/rss/channel/itunes:summary"]) { if (processedText.length > 0) info.summary = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/itunes:author"]) { if (processedText.length > 0) info.author = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rss/channel/itunes:subtitle"]) { if (processedText.length > 0) info.subTitle = processedText; processed = YES; }
                    }
                    
                    break;
                }
                case FeedTypeRSS1: {
                    
                    // Item
                    if (!processed) {
                        if ([currentPath isEqualToString:@"/rdf:RDF/item/title"]) { if (processedText.length > 0) item.title = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rdf:RDF/item/link"]) { if (processedText.length > 0) item.link = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rdf:RDF/item/dc:identifier"]) { if (processedText.length > 0) item.identifier = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rdf:RDF/item/description"]) { if (processedText.length > 0) item.summary = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rdf:RDF/item/content:encoded"]) { if (processedText.length > 0) item.content = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rdf:RDF/item/dc:date"]) { if (processedText.length > 0) item.date = [NSDate dateFromInternetDateTimeString:processedText formatHint:DateFormatHintRFC3339]; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rdf:RDF/item/enc:enclosure"]) { [self createEnclosureFromAttributes:currentElementAttributes andAddToItem:item]; processed = YES; }
                    }
                    
                    // Info
                    if (!processed && feedParseType != ParseTypeItemsOnly) {
                        if ([currentPath isEqualToString:@"/rdf:RDF/channel/title"]) { if (processedText.length > 0) info.title = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rdf:RDF/channel/description"]) { if (processedText.length > 0) info.summary = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/rdf:RDF/channel/link"]) { if (processedText.length > 0) info.link = processedText; processed = YES; }
                    }
                    
                    break;
                }
                case FeedTypeAtom: {
                    
                    // Item
                    if (!processed) {
                        if ([currentPath isEqualToString:@"/feed/entry/title"]) { if (processedText.length > 0) item.title = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/feed/entry/link"]) { [self processAtomLink:currentElementAttributes andAddToMWObject:item]; processed = YES; }
                        else if ([currentPath isEqualToString:@"/feed/entry/id"]) { if (processedText.length > 0) item.identifier = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/feed/entry/summary"]) { if (processedText.length > 0) item.summary = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/feed/entry/content"]) { if (processedText.length > 0) item.content = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/feed/entry/published"]) { if (processedText.length > 0) item.date = [NSDate dateFromInternetDateTimeString:processedText formatHint:DateFormatHintRFC3339]; processed = YES; }
                        else if ([currentPath isEqualToString:@"/feed/entry/updated"]) { if (processedText.length > 0) item.updated = [NSDate dateFromInternetDateTimeString:processedText formatHint:DateFormatHintRFC3339]; processed = YES; }
                    }
                    
                    // Info
                    if (!processed && feedParseType != ParseTypeItemsOnly) {
                        if ([currentPath isEqualToString:@"/feed/title"]) { if (processedText.length > 0) info.title = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/feed/description"]) { if (processedText.length > 0) info.summary = processedText; processed = YES; }
                        else if ([currentPath isEqualToString:@"/feed/link"]) { [self processAtomLink:currentElementAttributes andAddToMWObject:info]; processed = YES;}
                    }
                    
                    break;
                }
                default: break;
            }
        }
        
        // Adjust path
        self.currentPath = [currentPath stringByDeletingLastPathComponent];
        
        // If end of an item then tell delegate
        if (!processed) {
            if (((feedType == FeedTypeRSS || feedType == FeedTypeRSS1) && [qName isEqualToString:@"item"]) ||
                (feedType == FeedTypeAtom && [qName isEqualToString:@"entry"])) {
                
                // Dispatch item to delegate
                [self dispatchFeedItemToDelegate];
                
            }
        }
        
        // Check if the document has finished parsing and send off info if needed (i.e. there were no items)
        if (!processed) {
            if ((feedType == FeedTypeRSS && [qName isEqualToString:@"rss"]) ||
                (feedType == FeedTypeRSS1 && [qName isEqualToString:@"rdf:RDF"]) ||
                (feedType == FeedTypeAtom && [qName isEqualToString:@"feed"])) {
                
                // Document ending so if we havent sent off feed info yet, do so
                if (info && feedParseType != ParseTypeItemsOnly) [self dispatchFeedInfoToDelegate];
                
            }	
        }
        
    }
	
}

//- (void)parser:(NSXMLParser *)parser foundAttributeDeclarationWithName:(NSString *)attributeName 
//			forElement:(NSString *)elementName type:(NSString *)type defaultValue:(NSString *)defaultValue {
//	MWXMLLog(@"NSXMLParser: foundAttributeDeclarationWithName: %@", attributeName);
//}

- (void)parser:(NSXMLParser *)parser foundCDATA:(NSData *)CDATABlock {
	MWXMLLog(@"NSXMLParser: foundCDATA (%d bytes)", CDATABlock.length);
	
	// Remember characters
	NSString *string = nil;
	@try {
		
		// Try decoding with NSUTF8StringEncoding & NSISOLatin1StringEncoding
		string = [[NSString alloc] initWithData:CDATABlock encoding:NSUTF8StringEncoding];
		if (!string) string = [[NSString alloc] initWithData:CDATABlock encoding:NSISOLatin1StringEncoding];
		
		// Add - No need to encode as CDATA should not be encoded as it's ignored by the parser
		if (string) [currentText appendString:string];
		
	} @catch (NSException * e) { 
	} @finally {
	}
	
}

- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string {
	MWXMLLog(@"NSXMLParser: foundCharacters: %@", string);
	
	// Remember characters
	if (!parseStructureAsContent) {
		
		// Add characters normally
		[currentText appendString:string];
		
	} else {
		
		// If parsing structure as content then we should encode characters
		[currentText appendString:[string stringByEncodingHTMLEntities]];
		
	}
	
}

- (void)parserDidStartDocument:(NSXMLParser *)parser {
	MWXMLLog(@"NSXMLParser: parserDidStartDocument");
	
	// Debug Log
	MWLog(@"MWFeedParser: Parsing started");
	
	// Inform delegate
	if ([delegate respondsToSelector:@selector(feedParserDidStart:)])
		[delegate feedParserDidStart:self];
	
}

- (void)parserDidEndDocument:(NSXMLParser *)parser {
	MWXMLLog(@"NSXMLParser: parserDidEndDocument");
    
	// Debug Log
	MWLog(@"MWFeedParser: Parsing finished");
	
	// Inform delegate
	[self parsingFinished];
	
}

// Call if parsing error occured or parse was aborted
- (void)parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError {
	MWXMLLog(@"NSXMLParser: parseErrorOccurred: %@", parseError);
	
	// Fail with error
	if (!aborted) {
		// This method is called when legimitaly aboring the parser so ignore if this is the case
		[self parsingFailedWithErrorCode:MWErrorCodeFeedParsingError andDescription:[parseError localizedDescription]];
	}
	
}

- (void)parser:(NSXMLParser *)parser validationErrorOccurred:(NSError *)validError {
	MWXMLLog(@"NSXMLParser: validationErrorOccurred: %@", validError);
	
	// Fail with error
	[self parsingFailedWithErrorCode:MWErrorCodeFeedValidationError andDescription:[validError localizedDescription]];
	
}

#pragma mark -
#pragma mark Send Items to Delegate

- (void)dispatchFeedInfoToDelegate {
	if (info) {
        
		// Inform delegate
		if ([delegate respondsToSelector:@selector(feedParser:didParseFeedInfo:)])
			[delegate feedParser:self didParseFeedInfo:info];
		
		// Debug log
		MWLog(@"MWFeedParser: Feed info for \"%@\" successfully parsed", info.title);
		
		// Finish
		self.info = nil;
		
	}
}

- (void)dispatchFeedItemToDelegate {
	if (item) {
        
		// Process before hand
		if (!item.summary) { item.summary = item.content; item.content = nil; }
		if (!item.date && item.updated) { item.date = item.updated; }
        
		// Debug log
		MWLog(@"MWFeedParser: Feed item \"%@\" successfully parsed", item.title);
		
		// Inform delegate
		if ([delegate respondsToSelector:@selector(feedParser:didParseFeedItem:)])
			[delegate feedParser:self didParseFeedItem:item];
		
		// Finish
		self.item = nil;
		
	}
}

#pragma mark -
#pragma mark Helpers & Properties

// Set URL to parse and removing feed: uri scheme info
// https://en.wikipedia.org/wiki/Feed:_URI_scheme
- (void)setUrl:(NSURL *)value {
	
	// Check if an string was passed as old init asked for NSString not NSURL
	if ([value isKindOfClass:[NSString class]]) {
		value = [NSURL URLWithString:(NSString *)value];
	}
	
	// Create new instance of NSURL and check URL scheme
	NSURL *newURL = nil;
	if (value) {
		if ([value.scheme isEqualToString:@"feed"]) {
			
			// Remove feed URL scheme
			newURL = [NSURL URLWithString:[NSString stringWithFormat:@"%@%@",
                                           ([value.resourceSpecifier hasPrefix:@"//"] ? @"http:" : @""),
                                           value.resourceSpecifier]];
			
		} else {
			
			// Copy
			newURL = [value copy];
			
		}
	}
	
	// Set new url
	if (url) url = nil;
	url = newURL;
	
}

#pragma mark -
#pragma mark Misc

// Create an enclosure NSDictionary from enclosure (or link) attributes
- (BOOL)createEnclosureFromAttributes:(NSDictionary *)attributes andAddToItem:(MWFeedItem *)currentItem {
	
	// Create enclosure
	NSDictionary *enclosure = nil;
	NSString *encURL = nil, *encType = nil;
	NSNumber *encLength = nil;
	if (attributes) {
		switch (feedType) {
			case FeedTypeRSS: { // https://cyber.law.harvard.edu/rss/rss.html#ltenclosuregtSubelementOfLtitemgt
				// <enclosure>
				encURL = [attributes objectForKey:@"url"];
				encType = [attributes objectForKey:@"type"];
				encLength = [NSNumber numberWithLongLong:[((NSString *)[attributes objectForKey:@"length"]) longLongValue]];
				break;
			}
			case FeedTypeRSS1: { // https://www.xs4all.nl/~foz/mod_enclosure.html
				// <enc:enclosure>
				encURL = [attributes objectForKey:@"rdf:resource"];
				encType = [attributes objectForKey:@"enc:type"];
				encLength = [NSNumber numberWithLongLong:[((NSString *)[attributes objectForKey:@"enc:length"]) longLongValue]];
				break;
			}
			case FeedTypeAtom: { // https://www.atomenabled.org/developers/syndication/atom-format-spec.php#rel_attribute
				// <link rel="enclosure" href=...
				if ([[attributes objectForKey:@"rel"] isEqualToString:@"enclosure"]) {
					encURL = [attributes objectForKey:@"href"];
					encType = [attributes objectForKey:@"type"];
					encLength = [NSNumber numberWithLongLong:[((NSString *)[attributes objectForKey:@"length"]) longLongValue]];
				}
				break;
			}
			default: break;
		}
	}
	if (encURL) {
		NSMutableDictionary *e = [[NSMutableDictionary alloc] initWithCapacity:3];
		[e setObject:encURL forKey:@"url"];
		if (encType) [e setObject:encType forKey:@"type"];
		if (encLength) [e setObject:encLength forKey:@"length"];
		enclosure = [NSDictionary dictionaryWithDictionary:e];
	}
    
	// Add to item		 
	if (enclosure) {
		if (currentItem.enclosures) {
			currentItem.enclosures = [currentItem.enclosures arrayByAddingObject:enclosure];
		} else {
			currentItem.enclosures = [NSArray arrayWithObject:enclosure];
		}
		return YES;
	} else {
		return NO;
	}
	
}

// Process ATOM link and determine whether to ignore it, add it as the link element or add as enclosure
// Links can be added to MWObject (info or item)
- (BOOL)processAtomLink:(NSDictionary *)attributes andAddToMWObject:(id)MWObject {
	if (attributes && [attributes objectForKey:@"rel"]) {
		
		// Use as link if rel == alternate
		if ([[attributes objectForKey:@"rel"] isEqualToString:@"alternate"]) {
			[MWObject setLink:[attributes objectForKey:@"href"]]; // Can be added to MWFeedItem or MWFeedInfo
			return YES;
		}
		
		// Use as enclosure if rel == enclosure
		if ([[attributes objectForKey:@"rel"] isEqualToString:@"enclosure"]) {
			if ([MWObject isMemberOfClass:[MWFeedItem class]]) { // Enclosures can only be added to MWFeedItem
				[self createEnclosureFromAttributes:attributes andAddToItem:(MWFeedItem *)MWObject];
				return YES;
			}
		}
		
	}
	return NO;
}

@end