cog/Spotlight/SpotlightTransformers.m

//
//  SpotlightTransformers.m
//  Cog
//
//  Created by Matthew Grinshpun on 11/02/08.
//  Copyright 2008 Matthew Leon Grinshpun. All rights reserved.
//

#import "SpotlightTransformers.h"
#import "SpotlightWindowController.h"

// This is what we use instead of an outlet for PausingQueryTransformer
static SpotlightWindowController *searchController;

@implementation PausingQueryTransformer
+ (Class)transformedValueClass {
	return [NSArray class];
}
+ (BOOL)allowsReverseTransformation {
	return NO;
}

+ (void)setSearchController:(SpotlightWindowController *)aSearchController {
	searchController = aSearchController;
}

- (id)transformedValue:(id)value {
	// Rather unintuitively, this piece of code eliminates the "flicker"
	// when searching for new results, which resulted from a pause when the
	// search query stops gathering and sends an empty results array through KVO.
	if(([value count] > 0) || ([searchController.query isGathering])) {
		self.oldResults = (NSArray *)value;
	}
	return self.oldResults;
}

- (void)dealloc {
	self.oldResults = nil;
}

@synthesize oldResults;

@end

@implementation AuthorToArtistTransformer
+ (Class)transformedValueClass {
	return [NSString class];
}
+ (BOOL)allowsReverseTransformation {
	return NO;
}
- (id)transformedValue:(id)value {
	return [value objectAtIndex:0];
}
@end

@implementation PathToURLTransformer

+ (Class)transformedValueClass {
	return [NSURL class];
}
+ (BOOL)allowsReverseTransformation {
	return YES;
}

// Convert from path to NSURL
- (id)transformedValue:(id)value {
	if(value == nil) return nil;

	return [NSURL fileURLWithPath:value];
}

// Convert from NSURL to path
- (id)reverseTransformedValue:(id)value {
	if(value == nil) return nil;

	return [value path];
}

@end

@implementation StringToSearchScopeTransformer

+ (Class)transformedValueClass {
	return [NSArray class];
}
+ (BOOL)allowsReverseTransformation {
	return NO;
}

// Convert from URL string to Search Scope
- (id)transformedValue:(id)value {
	if(value == nil) return nil;

	NSURL *scope = [NSURL URLWithString:value];
	return @[scope];
}

@end

@implementation NumberToStringTransformer

+ (Class)transformedValueClass {
	return [NSString class];
}
+ (BOOL)allowsReverseTransformation {
	return NO;
}

// Convert from NSNumber to NSString
- (id)transformedValue:(id)value {
	if(value == nil) return nil;

	// If there's an NS/CFNumber hiding in here...
	if([value respondsToSelector:@selector(stringValue)]) {
		return [value stringValue];
	}

	return value;
}

@end