root/Footagehead/trunk/FHFeedHandler.m

/* $Id$ */

/*
 *  Copyright (c) 2003-2007 Axel Andersson
 *  All rights reserved.
 * 
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#import "FHFeedHandler.h"
#import "FHFlickrHandler.h"
#import "FHFile.h"
#import "FHHTMLParser.h"

enum FHFeedParseMode {
        FHFeedParseHeader,
        FHFeedParseItems,
};
typedef enum FHFeedParseMode            FHFeedParseMode;


@interface FHFeedHandler(Private)

- (void)_parse;
- (void)_parseImageHeaderInTree:(CFXMLTreeRef)imageTree;

@end


@implementation FHFeedHandler(Private)

- (void)_parse {
        NSMutableDictionary             *items;
        NSString                                *dividerKey, *name, *itemName;
        CFXMLTreeRef                    contentTree, tree, itemTree;
        CFXMLNodeRef                    node, itemNode;
        FHFeedParseMode                 mode;
        NSUInteger                              i, count, j, itemCount;
        
        contentTree = [self contentTree];
        dividerKey = [self itemDividerKey];
        count = CFTreeGetChildCount(contentTree);
        mode = FHFeedParseHeader;

        _header = [[NSMutableDictionary alloc] initWithCapacity:10];
        _items = [[NSMutableArray alloc] initWithCapacity:count];

        for(i = 0; i < count; i++) {
                tree = CFTreeGetChildAtIndex(contentTree, i);
                node = CFXMLTreeGetNode(tree);
                name = (NSString *) CFXMLNodeGetString(node);
                
                if([name isEqualToString:dividerKey])
                        mode = FHFeedParseItems;
                
                if(mode == FHFeedParseHeader) {
                        if([name isEqualTo:@"image"])
                                [self _parseImageHeaderInTree:tree];
                        
                        [_header setObject:[self valueOfTree:tree] forKey:name];
                }
                else if(mode == FHFeedParseItems) {
                        itemCount = CFTreeGetChildCount(tree);
                        items = [[NSMutableDictionary alloc] initWithCapacity:itemCount];
                        
                        for(j = 0; j < itemCount; j++) {
                                itemTree = CFTreeGetChildAtIndex(tree, j);
                                itemNode = CFXMLTreeGetNode(itemTree);
                                itemName = (NSString *) CFXMLNodeGetString(itemNode);
                                
                                [items setObject:[self valueOfTree:itemTree] forKey:itemName];
                        }
                        
                        [_items addObject:items];
                        [items release];
                }
        }
}



- (void)_parseImageHeaderInTree:(CFXMLTreeRef)imageTree {
        NSString                *name;
        CFXMLTreeRef    tree;
        CFXMLNodeRef    node;
        NSUInteger              i, count;
        
        count = CFTreeGetChildCount(imageTree);
                
        for(i = 0; i < count; i++) {
                tree = CFTreeGetChildAtIndex(imageTree, i);
                node = CFXMLTreeGetNode(tree);
                name = (NSString *) CFXMLNodeGetString(node);
                
                [_header setObject:[self valueOfTree:tree] forKey:[@"image" stringByAppendingString:name]];
        }
}

@end


@implementation FHFeedHandler

+ (Class)handlerForURL:(WIURL *)url {
        NSString        *host;
        
        host = [url host];
        
        if([host hasSuffix:@"flickr.com"])
                return [FHFlickrHandler class];
        
        return self;
}



#pragma mark -

- (id)initHandlerWithURL:(WIURL *)url feed:(CFXMLTreeRef)feed {
        CFXMLNodeRef    node;
        NSString                *name;
        FHFeedFormat    format;
        
        format = FHFeedUnknown;
        
        if(CFTreeGetChildCount(feed) >= 2) {
                node = CFXMLTreeGetNode(CFTreeGetChildAtIndex(feed, 1));
                name = (NSString *) CFXMLNodeGetString(node);
        
                if([name isEqualToString:@"rss"])
                        format = FHFeedRSS;
                else if([name isEqualToString:@"feed"])
                        format = FHFeedAtom;
        }

        return [self initHandlerWithURL:url feed:feed format:format];
}



- (id)initHandlerWithURL:(WIURL *)url feed:(CFXMLTreeRef)feed format:(FHFeedFormat)format {
        CFXMLTreeRef    rssTree;
        
        self = [super initHandlerWithURL:url];
        
        _feed = (CFXMLTreeRef) CFRetain(feed);
        _format = format;

        if(_format == FHFeedRSS) {
                rssTree = [self treeWithName:@"rss" inTree:_feed];
                
                if(!rssTree)
                        rssTree = [self treeWithName:@"rdf:RDF" inTree:_feed];
                
                if(!rssTree) {
                        [self release];
                        
                        return NULL;
                }
                
                _contentTree = [self treeWithName:@"channel" inTree:rssTree];
                
                if(!_contentTree)
                        _contentTree = [self treeWithName:@"rss:channel" inTree:rssTree];
                
                if(!_contentTree) {
                        [self release];
                        
                        return NULL;
                }
        }
        
        [self _parse];
                
        return self;
}



- (void)dealloc {
        CFRelease(_feed);
        
        [super dealloc];
}



#pragma mark -

- (NSString *)itemDividerKey {
        switch(_format) {
                case FHFeedUnknown:
                        return NULL;
                        break;

                case FHFeedRSS:
                        return @"item";
                        break;

                case FHFeedAtom:
                        return @"entry";
                        break;
        }
        
        return NULL;
}



- (NSString *)itemContentKey {
        switch(_format) {
                case FHFeedUnknown:
                        return NULL;
                        break;

                case FHFeedRSS:
                        return @"description";
                        break;

                case FHFeedAtom:
                        return @"content";
                        break;
        }
        
        return NULL;
}



- (CFXMLTreeRef)contentTree {
        return _contentTree;
}



- (CFXMLTreeRef)treeWithName:(NSString *)name inTree:(CFXMLTreeRef)tree {
        NSString                *itemName;
        CFXMLTreeRef    itemTree;
        CFXMLNodeRef    node;
        NSUInteger              i, count;
        
        count = CFTreeGetChildCount(tree);
        
        for(i = 0; i < count; i++) {
                itemTree        = CFTreeGetChildAtIndex(tree, i);
                node            = CFXMLTreeGetNode(itemTree);
                itemName        = (NSString *) CFXMLNodeGetString(node);
                
                if([itemName isEqualToString:name])
                        return itemTree;
        }
        
        return NULL;
}



- (NSString *)valueOfTree:(CFXMLTreeRef)tree {
        NSMutableString         *value;
        NSString                        *name;
        CFXMLNodeRef            node;
        NSUInteger                      i, count;
        
        value = [NSMutableString string];
        count = CFTreeGetChildCount(tree);
        
        for(i = 0; i < count; i++) {
                node = CFXMLTreeGetNode(CFTreeGetChildAtIndex(tree, i));
                name = (NSString *) CFXMLNodeGetString(node);
                
                if(name) {
                        if(CFXMLNodeGetTypeCode(node) == kCFXMLNodeTypeEntityReference) {
                                if([name isEqualToString:@"lt"])
                                        name = @"<";
                                else if([name isEqualToString:@"gt"])
                                        name = @">";
                                else if([name isEqualToString:@"quot"])
                                        name = @"\"";
                                else if([name isEqualToString:@"amp"])
                                        name = @"&";
                        }
                                                
                        [value appendString:name];
                }
        }
        
        return value;
}



#pragma mark -

- (NSArray *)files {
        NSDictionary    *item;
        NSArray                 *links;
        NSString                *content;
        NSUInteger              i, index, count, j, linkCount;
        
        if(!_files) {
                count = [_items count];
                _files = [[NSMutableArray alloc] initWithCapacity:count];
                
                for(i = index = 0; i < count; i++) {
                        item = [_items objectAtIndex:i];
                        content = [item objectForKey:[self itemContentKey]];
                        links = [FHHTMLParser imageLinksInHTML:content baseURL:[self URL]];
                        
                        for(j = 0, linkCount = [links count]; j < linkCount; j++) {
                                [_files addObject:[FHFile fileWithURL:[links objectAtIndex:j] isDirectory:NO]];
                                
                                _numberOfFiles++;
                                _numberOfImages++;
                        }
                }
        }
        
        return _files;
}



- (BOOL)hasParent {
        return NO;
}



- (NSArray *)stringComponents {
        return [NSArray arrayWithObject:[_header objectForKey:@"title"]];
}



- (NSArray *)URLComponents {
        return [NSArray arrayWithObject:[self URL]];
}

@end