IMBAppleMediaParser.m

/*
 iMedia Browser Framework <http://karelia.com/imedia/>
 
 Copyright (c) 2005-2011 by Karelia Software et al.
 
 iMedia Browser is based on code originally developed by Jason Terhorst,
 further developed for Sandvox by Greg Hulands, Dan Wood, and Terrence Talbot.
 The new architecture for version 2.0 was developed by Peter Baumgartner.
 Contributions have also been made by Matt Gough, Martin Wennerberg and others
 as indicated in source files.
 
 The iMedia Browser Framework is licensed under the following terms:
 
 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 all or substantial portions of 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:
 
 Redistributions of source code must retain the original terms stated here,
 including this list of conditions, the disclaimer noted below, and the
 following copyright notice: Copyright (c) 2005-2011 by Karelia Software et al.
 
 Redistributions in binary form must include, in an end-user-visible manner,
 e.g., About window, Acknowledgments window, or similar, either a) the original
 terms stated here, including this list of conditions, the disclaimer noted
 below, and the aforementioned copyright notice, or b) the aforementioned
 copyright notice and a link to karelia.com/imedia.
 
 Neither the name of Karelia Software, nor Sandvox, nor the names of
 contributors to iMedia Browser may be used to endorse or promote products
 derived from the Software without prior and express written permission from
 Karelia Software or individual contributors, as appropriate.
 
 Disclaimer: THE SOFTWARE IS PROVIDED BY THE COPYRIGHT OWNER AND CONTRIBUTORS
 "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 OF, OR OTHER DEALINGS IN, THE SOFTWARE.
 */


// Author: Jörg Jacobsen


//----------------------------------------------------------------------------------------------------------------------

#pragma mark HEADERS

#import "IMBAppleMediaParser.h"
#import "NSFileManager+iMedia.h"
#import "IMBNode.h"
#import "IMBNodeObject.h"
#import "IMBiPhotoEventObjectViewController.h"
#import "IMBFaceObjectViewController.h"
#import "IMBImageViewController.h"
#import "NSImage+iMedia.h"
#import "NSString+iMedia.h"


//----------------------------------------------------------------------------------------------------------------------

#pragma mark CONSTANTS

// node object types of interest for skimming

NSString* const kIMBiPhotoNodeObjectTypeEvent = @"events";
NSString* const kIMBiPhotoNodeObjectTypeFace  = @"faces";


//----------------------------------------------------------------------------------------------------------------------

#pragma mark -

@interface IMBAppleMediaParser ()

- (NSString*) imagePathForImageKey:(NSString*)inImageKey;
- (NSString*) imagePathForFaceIndex:(NSNumber*)inFaceIndex inImageWithKey:(NSString*)inImageKey;

@end


//----------------------------------------------------------------------------------------------------------------------

#pragma mark -

@implementation IMBAppleMediaParser

@synthesize plist = _plist;
@synthesize modificationDate = _modificationDate;


//----------------------------------------------------------------------------------------------------------------------

#pragma mark -
#pragma mark Parsing

//----------------------------------------------------------------------------------------------------------------------
// iPhoto and Aperture do not include events nor faces in the album list. To let events or faces also be shown
// in the browser we let events (aka rolls) and faces pose as albums in the album list.

- (void) addSpecialAlbumsToAlbumsInLibrary:(NSMutableDictionary*)inLibraryDict
{	
	NSArray* oldAlbumList = [inLibraryDict objectForKey:@"List of Albums"];		
	
	if (oldAlbumList != nil && [oldAlbumList count]>0)
	{
		NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
		
		NSNumber* photosDictIndex = nil;
		NSDictionary *photosDict = [self allPhotosAlbumInAlbumList:oldAlbumList atIndex:&photosDictIndex];
		
		if (photosDict && photosDictIndex)
		{
			// To insert events and faces into the album list we have to re-create it mutable style
			NSMutableArray *newAlbumList = [NSMutableArray arrayWithArray:oldAlbumList];
			
			// events album right before photos album
			
			if ([inLibraryDict objectForKey:@"List of Rolls"])
			{
				NSNumber *eventsId = [NSNumber numberWithUnsignedInt:EVENTS_NODE_ID];
				NSString *eventsName = NSLocalizedStringWithDefaultValue(@"IMB.iPhotoParser.events", nil, IMBBundle(), @"Events", @"Events node shown in iPhoto library");
				
				NSDictionary* events = [[NSDictionary alloc] initWithObjectsAndKeys:
										eventsId,   @"AlbumId",
										eventsName, @"AlbumName",
										@"Events",  @"Album Type",
										[photosDict objectForKey:@"Parent"], @"Parent", nil];
				
				[newAlbumList insertObject:events atIndex:[photosDictIndex unsignedIntegerValue]];
				IMBRelease(events);
				photosDictIndex = [NSNumber numberWithUnsignedInteger:[photosDictIndex unsignedIntegerValue] + 1];
			}
			
			// Faces album right after photos album
			
			if ([inLibraryDict objectForKey:@"List of Faces"])
			{
				NSNumber *facesId = [NSNumber numberWithUnsignedInt:FACES_NODE_ID];
				NSString *facesName = NSLocalizedStringWithDefaultValue(@"IMB.iPhotoParser.faces", nil, IMBBundle(), @"Faces", @"Faces node shown in iPhoto library");
				
				NSDictionary* faces = [[NSDictionary alloc] initWithObjectsAndKeys:
									   facesId,   @"AlbumId",
									   facesName, @"AlbumName",
									   @"Faces",  @"Album Type",
									   [photosDict objectForKey:@"Parent"], @"Parent", nil];
				
				[newAlbumList insertObject:faces atIndex:[photosDictIndex unsignedIntegerValue] + 1];
				IMBRelease(faces);
			}
			
			// Replace the old albums array.
			[inLibraryDict setValue:newAlbumList forKey:@"List of Albums"];
		}
		[pool drain];
	}
}


//----------------------------------------------------------------------------------------------------------------------
// Load the XML file into a plist lazily (on demand). If we notice that an existing cached plist is out-of-date 
// we get rid of it and load it anew...

- (NSDictionary*) plist
{
	NSDictionary* result = nil;
	NSError* error = nil;
	NSString* path = (NSString*)self.mediaSource;
	
	if ([[NSFileManager imb_threadSafeManager] fileExistsAtPath:path])
	{
		NSDictionary* metadata = [[NSFileManager imb_threadSafeManager] attributesOfItemAtPath:path error:&error];
		NSDate* modificationDate = [metadata objectForKey:NSFileModificationDate];
		
		@synchronized(self)
		{
			if ([self.modificationDate compare:modificationDate] == NSOrderedAscending)
			{
				self.plist = nil;
			}
			
			if (_plist == nil)
			{
				// Since we want to add events and faces to the list of albums we will need
				// to modify the album data dictionary (see further down below)
				NSMutableDictionary* dict = [NSMutableDictionary dictionaryWithContentsOfFile:path];
				
				// WORKAROUND
				if (dict == nil || 0 == dict.count)	// unable to read. possibly due to unencoded '&'.  rdar://7469235
				{
					NSData *data = [NSData dataWithContentsOfFile:path];
					if (data)
					{
						NSString *eString = nil;
						NSError *e = nil;
						@try
						{
							NSXMLDocument *xmlDoc = [[NSXMLDocument alloc] initWithData:data
																				options:NSXMLDocumentTidyXML error:&e];
							dict = [NSPropertyListSerialization
									propertyListFromData:[xmlDoc XMLData]
									mutabilityOption:0					// Apple doc: The opt parameter is currently unused and should be set to 0.
									format:NULL errorDescription:&eString];
							[xmlDoc release];
							
							// the assignment to 'dict' in the code above yields
							// a mutable dictionary as this code snippet would reveal:
							// Class dictClass = [dict classForCoder];
							// NSLog(@"Dictionary class: %@", [dictClass description]);
						}
						@catch(NSException *e)
						{
							NSLog(@"%s %@", __FUNCTION__, e);
						}
						// When we start targetting 10.6, we should use propertyListWithData:options:format:error:
					}
				}			
				
				//	If there is an AlbumData.xml file, there should be something inside!
				
				if (dict == nil || 0 == dict.count)
				{
					NSLog (@"The iPhoto or Aperture XML file seems to be empty. This is an unhealthy condition!");
				}
				
				// Since this parser confines itself to deal with the "List of Albums" only
				// we add an events node to the album list to incorporate events in the browser.
				// This is why we need a mutable library dictionary.
				
				if (dict)
				{
					[self addSpecialAlbumsToAlbumsInLibrary:dict];
				}
				
				self.plist = dict;
				self.modificationDate = modificationDate;
			}
			
			result = [[_plist retain] autorelease];
		}
	}
	
	return result;
}


//----------------------------------------------------------------------------------------------------------------------


#pragma mark -
#pragma mark Custom view controller support

- (NSViewController*) customObjectViewControllerForNode:(IMBNode*)inNode
{
	// Use custom view for events
	
    if ([self isEventsNode:inNode])
	{
		NSDictionary* userInfo = [NSDictionary dictionaryWithObjectsAndKeys:
								  kIMBiPhotoNodeObjectTypeEvent, @"nodeObjectType", nil];
		
		NSViewController* viewController = [[[IMBiPhotoEventObjectViewController alloc] initWithDelegate:self userInfo:userInfo] autorelease];
		[viewController view];
		return viewController;
	}
	
    if ([self isFacesNode:inNode])
	{
		NSDictionary* userInfo = [NSDictionary dictionaryWithObjectsAndKeys:
								  kIMBiPhotoNodeObjectTypeFace, @"nodeObjectType", nil];
		
		NSViewController* viewController = [[[IMBFaceObjectViewController alloc] initWithDelegate:self userInfo:userInfo] autorelease];
		[viewController view];
		return viewController;
	}
	
	return [super customObjectViewControllerForNode:inNode];
}


//----------------------------------------------------------------------------------------------------------------------


#pragma mark -
#pragma mark IMBSkimmableObjectViewControllerDelegate

- (NSUInteger) childrenCountOfNodeObject:(IMBNodeObject*)inNodeObject userInfo:(NSDictionary*)inUserInfo
{
//	return [[inNodeObject.preliminaryMetadata objectForKey:@"PhotoCount"] integerValue];
	return [[inNodeObject.preliminaryMetadata objectForKey:@"KeyList"] count];	// More reliable for Aperture! Avoids out-of-bounds exceptions.
}


- (NSString*) imagePathForChildOfNodeObject:(IMBNodeObject*)inNodeObject atIndex:(NSUInteger)inIndex userInfo:(NSDictionary*)inUserInfo
{
	NSString* imageKey = [[inNodeObject.preliminaryMetadata objectForKey:@"KeyList"] objectAtIndex:inIndex];
	
	// Faces
	if ([[inUserInfo objectForKey:@"nodeObjectType"] isEqualToString:kIMBiPhotoNodeObjectTypeFace])
	{
		// Get this face's data describing its occurence in the inIndex'th image 
		NSDictionary* imageFaceMetadata = [[[inNodeObject preliminaryMetadata] objectForKey:@"ImageFaceMetadataList"] objectAtIndex:inIndex];
		
		// Get this face's index inside of this image
		NSNumber* faceIndex = [imageFaceMetadata objectForKey:@"face index"];
		
		// Finally, get the path to this face's occurence
		NSString* imagePath = [self imagePathForFaceIndex:faceIndex inImageWithKey:imageKey];
		
		//NSLog(@"Skimming controller asked delegate for image path and receives: %@", imagePath);
		
		return imagePath;
	}
	
	// Events
	return [self imagePathForImageKey:imageKey];
}


- (NSString*) imagePathForKeyChildOfNodeObject:(IMBNodeObject*)inNodeObject userInfo:(NSDictionary*)inUserInfo
{
	NSString* imageKey = [inNodeObject.preliminaryMetadata objectForKey:@"KeyPhotoKey"];
	
	// Faces
	if ([[inUserInfo objectForKey:@"nodeObjectType"] isEqualToString:kIMBiPhotoNodeObjectTypeFace])
	{
		// Get this face's index inside of this image
		NSNumber* faceIndex = [[inNodeObject preliminaryMetadata] objectForKey:@"key image face index"];
		
		// Get the path to this face's occurence
		NSString* imagePath = [self imagePathForFaceIndex:faceIndex inImageWithKey:imageKey];
		
		return imagePath;
	}
	
	// Events
	return [self imagePathForImageKey:imageKey];
}


//----------------------------------------------------------------------------------------------------------------------

#pragma mark -
#pragma mark To be subclassed

//----------------------------------------------------------------------------------------------------------------------
// Create an identifier from the provided id and id space. An example is "IMBiPhotoParser://FaceId/17"...

- (NSString*) identifierForId:(NSNumber*) inId inSpace:(NSString*) inIdSpace
{
	NSLog(@"%s Please use a custom subclass of IMBAppleMediaParser...",__FUNCTION__);
	[[NSException exceptionWithName:@"IMBProgrammerError" reason:@"Please use a custom subclass of IMBAppleMediaParser" userInfo:nil] raise];
	
	return nil;
}


//----------------------------------------------------------------------------------------------------------------------
// returns whether this album type should be used. Must be subclassed.

- (BOOL) shouldUseAlbumType:(NSString*)inAlbumType
{
	NSLog(@"%s Please use a custom subclass of IMBAppleMediaParser...",__FUNCTION__);
	[[NSException exceptionWithName:@"IMBProgrammerError" reason:@"Please use a custom subclass of IMBAppleMediaParser" userInfo:nil] raise];
	
	return NO;
}


//----------------------------------------------------------------------------------------------------------------------
// Returns whether inAlbumDict should be used. Must be subclassed.

- (BOOL) shouldUseAlbum:(NSDictionary*)inAlbumDict images:(NSDictionary*)inImages
{
	NSLog(@"%s Please use a custom subclass of IMBAppleMediaParser...",__FUNCTION__);
	[[NSException exceptionWithName:@"IMBProgrammerError" reason:@"Please use a custom subclass of IMBAppleMediaParser" userInfo:nil] raise];
	
	return NO;
}


//----------------------------------------------------------------------------------------------------------------------
// Returns a dictionary that contains the "true" KeyList, KeyPhotoKey and PhotoCount values for the provided node.
// (The values provided by the according dictionary in .plist are mostly wrong because we separate node children by
// media types 'Image' and 'Movie' into different views.) Must be subclassed.

- (NSDictionary*) childrenInfoForNode:(IMBNode*)inNode images:(NSDictionary*)inImages
{
	NSLog(@"%s Please use a custom subclass of IMBAppleMediaParser...",__FUNCTION__);
	[[NSException exceptionWithName:@"IMBProgrammerError" reason:@"Please use a custom subclass of IMBAppleMediaParser" userInfo:nil] raise];
	
	return nil;
}


//----------------------------------------------------------------------------------------------------------------------
// Returns an icon for an album of this type. Must be subclassed.

- (NSImage*) iconForAlbumType:(NSString*)inType
{
	NSLog(@"%s Please use a custom subclass of IMBAppleMediaParser...",__FUNCTION__);
	[[NSException exceptionWithName:@"IMBProgrammerError" reason:@"Please use a custom subclass of IMBAppleMediaParser" userInfo:nil] raise];
	
	return nil;
}


//----------------------------------------------------------------------------------------------------------------------
// Returns whether inAlbumDict is the "Photos" album. Must be subclassed.

- (BOOL) isAllPhotosAlbum:(NSDictionary*)inAlbumDict
{
	NSLog(@"%s Please use a custom subclass of IMBAppleMediaParser...",__FUNCTION__);
	[[NSException exceptionWithName:@"IMBProgrammerError" reason:@"Please use a custom subclass of IMBAppleMediaParser" userInfo:nil] raise];
	
	return NO;
}


//----------------------------------------------------------------------------------------------------------------------

#pragma mark -
#pragma mark Image location

//----------------------------------------------------------------------------------------------------------------------
// The image location represents an image path to the image to be used for display inside of the browser (a preview of
// of the original image). By default we use the path to the image's thumbnail (key: "ThumbPath").
// Subclass for distinct behavior.

- (NSString*) imageLocationForObject:(NSDictionary*)inObjectDict
{
	return [inObjectDict objectForKey:@"ThumbPath"];
}


//----------------------------------------------------------------------------------------------------------------------
// Returns the image location for the image represented by inImageKey in the master image list (aka dictionary)

- (NSString*) imagePathForImageKey:(NSString*)inImageKey
{
	NSDictionary* images = [[self plist] objectForKey:@"Master Image List"];
	NSDictionary* imageDict = [images objectForKey:inImageKey];
	NSString* imagePath = [self imageLocationForObject:imageDict];
	
	return imagePath; 
}


//----------------------------------------------------------------------------------------------------------------------
// Returns the image location for the clipped face in the image represented by inImageKey in the master image list
// (aka dictionary)

- (NSString*) imagePathForFaceIndex:(NSNumber*)inFaceIndex inImageWithKey:(NSString*)inImageKey
{
	NSString* imagePath = [self imagePathForImageKey:inImageKey];
	
	return [NSString stringWithFormat:@"%@_face%@.%@",
			[imagePath stringByDeletingPathExtension],
			inFaceIndex,
			[imagePath pathExtension]];
}


//----------------------------------------------------------------------------------------------------------------------

#pragma mark -
#pragma mark Subnode creation and node population

//----------------------------------------------------------------------------------------------------------------------
// Returns array of all face dictionaries (sorted by name). These are also enriched by several keys:
// ImageFaceMetadataList: list of meta info of face occurences in images (sorted by date)
// KeyPhotoKey:           key of key image ('KeyPhotoKey' is an event-compatible key)
// KeyList:               list of all images in which a face occurs (sorted by date)

- (NSArray*) faces:(NSDictionary*)inFaces collectedFromImages:(NSDictionary*)inImages
{
	// Need the enriched copy mutable style
	NSMutableDictionary* facesDict = [NSMutableDictionary dictionaryWithDictionary:inFaces];
	
	// Collect all occurences faces. We iterate over master images because only there AlbumData.xml
	// stores occurences of faces.
	
	NSArray* facesOnImage = nil;
	NSDictionary* imageDict = nil;
	NSMutableDictionary* faceDict = nil;	// Will need to add keys like "KeyList" to dictionary
	
	NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
	
	for (NSString* imageDictKey in [inImages keyEnumerator])
	{
		imageDict = [inImages objectForKey:imageDictKey];
		
		// Get all known faces that appear on this image
		facesOnImage = [imageDict objectForKey:@"Faces"];
		
		NSString* imageFaceKey = nil;
		NSMutableArray* imageFaceMetadataList = nil;
		NSDictionary* imageFaceMetadata = nil;
		for (NSDictionary* imageFaceDict in facesOnImage)
		{
			// Get face dictionary for given face key.
			// Face dictionary will be the basis of our subnode to be created.
			
			imageFaceKey = [imageFaceDict objectForKey:@"face key"];
			faceDict = [facesDict objectForKey:imageFaceKey];
			
			// It might well be that found face in image is now longer known...
			if (faceDict)
			{
				// Coming here we found a face on an image and this face is known.
				// Now add some key/value pairs to face dictionary
				
				// First convert to a mutable dictionary to be able to add the extra pairs
				faceDict = [NSMutableDictionary dictionaryWithDictionary:faceDict];
				[facesDict setObject:faceDict forKey:imageFaceKey];
				
				// Add image face meta data to this face (need this later)
				// (Create meta data list when first occurence of face in some image is detected)
				
				imageFaceMetadataList = [faceDict objectForKey:@"ImageFaceMetadataList"];
				if (!imageFaceMetadataList)
				{
					imageFaceMetadataList = [NSMutableArray array];
					[faceDict setObject:imageFaceMetadataList forKey:@"ImageFaceMetadataList"];
				}
				imageFaceMetadata = [NSDictionary dictionaryWithObjectsAndKeys:
									 imageDictKey, @"image key",
									 [imageFaceDict objectForKey:@"face index"], @"face index",
									 [imageDict objectForKey:@"DateAsTimerInterval"], @"DateAsTimerInterval", nil];
				
				[imageFaceMetadataList addObject:imageFaceMetadata];
				
			} else {
				// We found a face in a master image but that face is not associated
				// with a known face anymore. Just skip this one.
				
				//NSLog(@"Found unknown face with ID %@ in image %@", faceKey, imageDictKey);
			}
		}
	}
	
	// For each face dictionary sort associated images by date (this is how iPhoto displays them)
	
	NSSortDescriptor* dateDescriptor = [[NSSortDescriptor alloc] initWithKey:@"DateAsTimerInterval" ascending:YES];
	NSArray* sortDescriptors = [NSArray arrayWithObject:dateDescriptor];
	[dateDescriptor release];
	
	NSArray* imageFaceMetadataList = nil;
	for (NSString* faceKey in [facesDict keyEnumerator])
	{
		faceDict = [facesDict objectForKey:faceKey];
		
		// Sort images related to face by date
		
		imageFaceMetadataList = [faceDict objectForKey:@"ImageFaceMetadataList"];
		if (imageFaceMetadataList)
		{
			imageFaceMetadataList = [imageFaceMetadataList sortedArrayUsingDescriptors:sortDescriptors];
		} else {
			// Obviously a metadata list has yet not been created for this face.
			// Given the code further above this really means that this face does not appear
			// on any image. This should probably not be but there were crash logs indicating just this.
			// Create an empty metadata list to avoid crash.
			imageFaceMetadataList = [NSArray array];
		}
		[faceDict setObject:imageFaceMetadataList forKey:@"ImageFaceMetadataList"];
		
		// Also provide key image key under an event-compatible key
		[faceDict setObject:[faceDict objectForKey:@"key image"] forKey:@"KeyPhotoKey"];
		
		// Also store a sorted key list in face dictionary
		[faceDict setObject:[imageFaceMetadataList valueForKey:@"image key"] forKey:@"KeyList"];
	}
	
	[pool drain];
	
	// Sort faces dictionary by names (this is how iPhoto displays faces)
	
	NSSortDescriptor* nameDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES];
	sortDescriptors = [NSArray arrayWithObject:nameDescriptor];
	[nameDescriptor release];
	
	NSArray* sortedFaces = [[facesDict allValues] sortedArrayUsingDescriptors:sortDescriptors];
	
	return sortedFaces;
}


//----------------------------------------------------------------------------------------------------------------------
// Populate faces node and create corresponding subnodes that each represent a single face

- (void) populateFacesNode:(IMBNode*)inNode 
				 withFaces:(NSDictionary*)inFaces
					images:(NSDictionary*)inImages
{
	// Pull all information on faces from faces dictionary and face occurences in images
	// into a faces array (sorted by name)
	NSArray* sortedFaces = [self faces:inFaces collectedFromImages:inImages];
	
	// Create the subNodes array on demand - even if turns out to be empty after exiting this method, 
	// because without creating an array we would cause an endless loop...
	NSMutableArray* subNodes = [NSMutableArray array];
	
	// Create the objects array on demand  - even if turns out to be empty after exiting this method, because
	// without creating an array we would cause an endless loop...
	NSMutableArray* objects = [[NSMutableArray alloc] initWithArray:inNode.objects];
	
	NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
	
	// Setup the loop
	
	NSUInteger index = 0;
	NSString* faceKeyPhotoKey = nil;
	NSString* path = nil;
	IMBNodeObject* object = nil;
	NSString* subNodeType = @"Face";
	
	for (NSDictionary* faceDict in sortedFaces)
	{
		NSString* subNodeName = [faceDict objectForKey:@"name"];
		
		if ([self shouldUseAlbumType:subNodeType] && 
			[self shouldUseAlbum:faceDict images:inImages])
		{
			// Create subnode for this node...
			
			IMBNode* subNode = [[[IMBNode alloc] init] autorelease];
			
			subNode.leaf = [self isLeafAlbumType:subNodeType];
			subNode.icon = [self iconForAlbumType:subNodeType];
			subNode.name = subNodeName;
			subNode.mediaSource = self.mediaSource;
			subNode.parser = self;
			
			// Keep a ref to face dictionary for potential later use
			subNode.attributes = faceDict;
			
			// Set the node's identifier. This is needed later to link it to the correct parent node.
			// Note that a faces dictionary always has a "key" key.
			
			NSNumber* subNodeId = [faceDict objectForKey:@"key"];
			subNode.identifier = [self identifierForId:subNodeId inSpace:FACES_ID_SPACE];
			
			// Add the new subnode to its parent (inRootNode)...
			
			[subNodes addObject:subNode];
			
			// Now create the visual object and link it to subnode just created
			
			object = [[IMBNodeObject alloc] init];
			[objects addObject:object];
			[object release];
			
			// Adjust keys "KeyPhotoKey", "KeyList", and "PhotoCount" in metadata dictionary
			// because movies and images are not jointly displayed in iMedia browser
			NSMutableDictionary* preliminaryMetadata = [NSMutableDictionary dictionaryWithDictionary:faceDict];
			[preliminaryMetadata addEntriesFromDictionary:[self childrenInfoForNode:subNode images:inImages]];
			
			object.preliminaryMetadata = preliminaryMetadata;	// This metadata from the XML file is available immediately
			object.metadata = nil;								// Build lazily when needed (takes longer)
			object.metadataDescription = nil;					// Build lazily when needed (takes longer)
			
			// Obtain key photo dictionary (key photo is displayed while not skimming)
			faceKeyPhotoKey = [object.preliminaryMetadata objectForKey:@"KeyPhotoKey"];
			NSDictionary* keyPhotoDict = [inImages objectForKey:faceKeyPhotoKey];
			
			path = [keyPhotoDict objectForKey:@"ImagePath"];
			
			object.representedNodeIdentifier = subNode.identifier;
			object.location = (id)path;
			object.name = subNode.name;
			object.parser = self;
			object.index = index++;
			
			object.imageLocation = [self imagePathForFaceIndex:[faceDict objectForKey:@"key image face index"] inImageWithKey:faceKeyPhotoKey];
			object.imageRepresentationType = [self requestedImageRepresentationType];
			object.imageRepresentation = nil;
		}
	}	
	[pool drain];
	inNode.subNodes = subNodes;
	inNode.objects = objects;
	[objects release];
}


#pragma mark -
#pragma mark Object description


+ (NSString*) objectCountFormatSingular
{
	return [IMBImageViewController objectCountFormatSingular];
}


+ (NSString*) objectCountFormatPlural
{
	return [IMBImageViewController objectCountFormatPlural];
}


//----------------------------------------------------------------------------------------------------------------------
// Events and Faces have other metadata than images or movies

- (NSString*) countableMetadataDescriptionForMetadata:(NSDictionary*)inMetadata
{
	NSMutableString* metaDesc = [NSMutableString string];
	
	NSNumber* count = [inMetadata objectForKey:@"PhotoCount"];
	if (count)
	{
		NSString* formatString = [count intValue] > 1 ?
		[[self class] objectCountFormatPlural] :
		[[self class] objectCountFormatSingular];
		
		[metaDesc appendFormat:formatString, [count intValue]];
	}
	
	NSNumber* dateAsTimerInterval = [inMetadata objectForKey:@"RollDateAsTimerInterval"];
	if (dateAsTimerInterval)
	{
		[metaDesc imb_appendNewline];
		NSDate* eventDate = [NSDate dateWithTimeIntervalSinceReferenceDate:[dateAsTimerInterval doubleValue]];
		
		NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
		[formatter setFormatterBehavior:NSDateFormatterBehavior10_4];
		[formatter setDateStyle:NSDateFormatterMediumStyle];	// medium date
		
		[metaDesc appendFormat:@"%@", [formatter stringFromDate:eventDate]];
		
		[formatter release];
	}
	return metaDesc;
}


//----------------------------------------------------------------------------------------------------------------------
// Convert metadata into a human readable string...

- (NSString*) metadataDescriptionForMetadata:(NSDictionary*)inMetadata
{
	// Events and Faces have other metadata than images
	
	if ([inMetadata objectForKey:@"PhotoCount"])		// Event, face, ...
	{
		return [self countableMetadataDescriptionForMetadata:inMetadata];
	}
	
	// Image
	return [NSImage imb_imageMetadataDescriptionForMetadata:inMetadata];
}


//----------------------------------------------------------------------------------------------------------------------

#pragma mark -
#pragma mark Convenience

//----------------------------------------------------------------------------------------------------------------------
// Returns events id space  (EVENTS_ID_SPACE) for album types "Face" and "Faces".
// Returns faces id space  (FACES_ID_SPACE) for album types "Face" and "Faces".
// Otherwise returns the albums id space (ALBUMS_ID_SPACE).

- (NSString*) idSpaceForAlbumType:(NSString*) inAlbumType
{
	if ([inAlbumType isEqualToString:@"Event"] || [inAlbumType isEqualToString:@"Events"])
	{
		return EVENTS_ID_SPACE;
	} else if ([inAlbumType isEqualToString:@"Face"] || [inAlbumType isEqualToString:@"Faces"])
	{
		return FACES_ID_SPACE;
	}
	return ALBUMS_ID_SPACE;
}


//----------------------------------------------------------------------------------------------------------------------
// Returns whether an album of this type exposes a disclosure triangle or not.

- (BOOL) isLeafAlbumType:(NSString*)inType
{
	return ![inType isEqualToString:@"Folder"] &&
	![inType isEqualToString:@"Events"] &&
	![inType isEqualToString:@"Faces"];
}


//----------------------------------------------------------------------------------------------------------------------
// Returns the standard album of all photos ("Photos") in its plist representation

- (NSDictionary*) allPhotosAlbumInAlbumList:(NSArray*)inAlbumList atIndex:(NSNumber**)outIndex
{
	NSUInteger i, count = [inAlbumList count];
	for (i = 0; i < count; i++) 
	{
		NSDictionary* albumDict = [inAlbumList objectAtIndex:i];
		if ([self isAllPhotosAlbum:albumDict])
		{
			*outIndex = [NSNumber numberWithUnsignedInteger:i];
			return albumDict;
		}
	}
	return nil;
}


//----------------------------------------------------------------------------------------------------------------------
// Returns IKImageBrowserCGImageRepresentationType

- (NSString*) requestedImageRepresentationType
{
	return IKImageBrowserCGImageRepresentationType;
}


//----------------------------------------------------------------------------------------------------------------------
// Returns whether inNode is the events node

- (BOOL) isEventsNode:(IMBNode*)inNode
{	
	NSNumber* eventsId = [NSNumber numberWithUnsignedInt:EVENTS_NODE_ID];
	NSString* eventsIdentifier = [self identifierForId:eventsId inSpace:EVENTS_ID_SPACE];
	
	return [inNode.identifier isEqualToString:eventsIdentifier];
}


//----------------------------------------------------------------------------------------------------------------------
// Returns whether inNode is the faces node

- (BOOL) isFacesNode:(IMBNode*)inNode
{	
	NSNumber* facesId= [NSNumber numberWithUnsignedInt:FACES_NODE_ID];
	NSString* facesIdentifier = [self identifierForId:facesId inSpace:FACES_ID_SPACE];
	
	return [inNode.identifier isEqualToString:facesIdentifier];
}


@end