FileSystemNode.m

/*

     File: FileSystemNode.m

 Abstract: An abstract wrapper node around the file system.

  Version: 1.1

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 */

#import "FileSystemNode.h"

@implementation FileSystemNode

- (id)initWithURL:(NSURL *)url {

    if (self = [super init]) {

        _url = [url retain];

    }

    return self;

}

- (void)dealloc {

    // We have to release the underlying ivars associated with our properties

    [_url release];

    [_children release];

    [super dealloc];

}

- (NSString *)description {

    return [NSString stringWithFormat:@"%@ - %@", super.description, _url];

}

@synthesize URL = _url;

@dynamic displayName, children, isDirectory, icon, labelColor;

- (NSString *)displayName {

    id value = nil;

    NSError *error = nil;

    BOOL success = NO;

    success = [_url getResourceValue:&value forKey:NSURLLocalizedNameKey error:&error];

    if (success && !value) { //If we got a nil value for the localized name, we will try the non-localized name

    success = [_url getResourceValue:&value forKey:NSURLNameKey error:&error];

    }

    if (success) {

    if (value) {

        return value;

    } else {

        return @""; //An empty string is more appropriate than nil

    }

    } else {

    return [error localizedDescription];

    }

}

- (NSImage *)icon {

    return [[NSWorkspace sharedWorkspace] iconForFile:[_url path]];

}

- (BOOL)isDirectory {

    id value = nil;

    [_url getResourceValue:&value forKey:NSURLIsDirectoryKey error:NULL];

    return [value boolValue];

}

- (NSColor *)labelColor {

    id value = nil;

    [_url getResourceValue:&value forKey:NSURLLabelColorKey error:NULL];

    return value;

}

- (NSArray *)children {

    if (_children == nil || _childrenDirty) {

        // This logic keeps the same pointers around, if possible.

        NSMutableDictionary *newChildren = [NSMutableDictionary new];

        NSString *parentPath = [_url path];

        NSArray *contentsAtPath = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:parentPath error:NULL];

    if (contentsAtPath) {   // We don't deal with the error

        for (NSString *filename in contentsAtPath) {

        // Use the filename as a key and see if it was around and reuse it, if possible

        if (_children != nil) {

            FileSystemNode *oldChild = [_children objectForKey:filename];

            if (oldChild != nil) {

            [newChildren setObject:oldChild forKey:filename];

            continue;

            }

        }

        // We didn't find it, add a new one

        NSString *fullPath = [parentPath stringByAppendingFormat:@"/%@", filename];

        NSURL *childURL = [NSURL fileURLWithPath:fullPath];

        if (childURL != nil) {

            // Wrap the child url with our node

            FileSystemNode *node = [[FileSystemNode alloc] initWithURL:childURL];

            [newChildren setObject:node forKey:filename];

            [node release];

        }

        }

    }

        [_children release];

        _children = newChildren;

        _childrenDirty = NO;

    }

    NSArray *result = [_children allValues];

    // Sort the children by the display name and return it

    result = [result sortedArrayUsingComparator:^(id obj1, id obj2) {

        NSString *objName = [obj1 displayName];

        NSString *obj2Name = [obj2 displayName];

        NSComparisonResult result = [objName compare:obj2Name options:NSNumericSearch | NSCaseInsensitiveSearch | NSWidthInsensitiveSearch | NSForcedOrderingSearch range:NSMakeRange(0, [objName length]) locale:[NSLocale currentLocale]];

        return result;

    }];

    return result;

}

- (void)invalidateChildren {

    _childrenDirty = YES;

    for (FileSystemNode *child in [_children allValues]) {

        [child invalidateChildren];

    }

}

@end