/*

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

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 Base class for the two parsers, this class handles interactions with a delegate object (the SongsViewController in this sample) and provides basic functionality common to both parsers.

*/

@import UIKit;

typedef NS_ENUM(int, XMLParserType) {

    XMLParserTypeAbstract = -1,

    XMLParserTypeNSXMLParser = 0,

    XMLParserTypeLibXMLParser

};

@class iTunesRSSParser, Song;

// Protocol for the parser to communicate with its delegate.

@protocol iTunesRSSParserDelegate <NSObject>

@optional

// Called by the parser when parsing is finished.

- (void)parserDidEndParsingData:(iTunesRSSParser *)parser;

// Called by the parser in the case of an error.

- (void)parser:(iTunesRSSParser *)parser didFailWithError:(NSError *)error;

// Called by the parser when one or more songs have been parsed. This method may be called multiple times.

- (void)parser:(iTunesRSSParser *)parser didParseSongs:(NSArray *)parsedSongs;

@end

#pragma mark -

@interface iTunesRSSParser : NSObject

@property (nonatomic, weak) id <iTunesRSSParserDelegate> delegate;

+ (NSString *)parserName;

+ (XMLParserType)parserType;

- (void)start;

// Subclasses must implement this method. It will be invoked on a secondary thread to keep the application responsive.

// The parsing can be quite CPU intensive on the device, so

// the user interface can be kept responsive by moving that work off the main thread. This does create additional

// complexity, as any code which interacts with the UI must then do so in a thread-safe manner.

- (void)downloadAndParse:(NSURL *)url;

// Subclasses should invoke these methods and let the superclass manage communication with the delegate.

// Each of these methods must be invoked on the main thread.

- (void)downloadStarted;

- (void)downloadEnded;

- (void)parseEnded;

- (void)parsedSong:(Song *)song;

- (void)parseError:(NSError *)error;

- (void)addToParseDuration:(NSNumber *)duration;

@end