#import <AppKit/AppKit.h>
#import <Foundation/Foundation.h>

@interface LWListener : NSObject <NSMetadataQueryDelegate> {
    NSMetadataQuery *_query;
    NSString *_cpCommand;
    NSString *_clipboardBase;
    NSString *_destinationBase;
}

- (void)go;
- (void)nogo;
- (void)change:(NSNotification *)notification;

@property (nonatomic, copy) NSString *cpCommand;
@property (nonatomic, copy) NSString *clipboardBase;
@property (nonatomic, copy) NSString *destinationBase;

@end

@implementation LWListener

@synthesize cpCommand = _cpCommand;
@synthesize clipboardBase = _clipboardBase;
@synthesize destinationBase = _destinationBase;

- (void)dealloc {
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    _query.delegate = nil;
    [_query release];
    [_cpCommand release];
    [_clipboardBase release];
    [_destinationBase release];
    [super dealloc];
}

- (id)init {
    if ((self = [super init])) {
        _query = [[NSMetadataQuery alloc] init];
        _query.delegate = self;

        // kMDItemIsScreenCapture is some magic I found on stackoverflow. I couldn't dig up
        // anything in the Apple docs about it.
        _query.predicate = [NSPredicate predicateWithFormat:@"kMDItemIsScreenCapture = 1"];

        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(change:) name:NSMetadataQueryDidUpdateNotification object:_query];
    }
    return self;
}

- (void)go {
    if (_query.isStarted) return;

    [_query startQuery];
}

- (void)nogo {
    if (_query.isStopped) return;

    [_query stopQuery];
}

- (void)change:(NSNotification *)notification {
    NSMetadataItem *item = [[notification.userInfo objectForKey:(NSString *)kMDQueryUpdateAddedItems] lastObject];
    if (item) {
        NSString *screenShotPath = [item valueForAttribute:NSMetadataItemPathKey];

        NSURL *urlOfFile = [NSURL fileURLWithPath:screenShotPath];
        NSString *nameWithRemoteUrl = [NSString stringWithFormat:@"%@%@", self.clipboardBase, [urlOfFile lastPathComponent]];
        nameWithRemoteUrl = [nameWithRemoteUrl stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
        NSPasteboard *pb = [NSPasteboard generalPasteboard];
        [pb clearContents];
        [pb writeObjects:[NSArray arrayWithObject:nameWithRemoteUrl]];

        [NSTask launchedTaskWithLaunchPath:@"/usr/bin/env" arguments:[NSArray arrayWithObjects:self.cpCommand, screenShotPath, self.destinationBase, nil]];
    }
}

@end

int main (int argc, const char * argv[]) {
    @autoreleasepool {
        NSProcessInfo *procInfo = [NSProcessInfo processInfo];
        NSLog(@"%@", procInfo.arguments);

        if ([procInfo.arguments count] < 4) {
            return 1;
        }

        LWListener *listener = [[[LWListener alloc] init] autorelease];

        listener.cpCommand = [procInfo.arguments objectAtIndex:1];
        listener.clipboardBase = [procInfo.arguments objectAtIndex:2];
        listener.destinationBase = [procInfo.arguments objectAtIndex:3];

        [listener go];

        [[NSRunLoop currentRunLoop] runUntilDate:[NSDate distantFuture]];
    }
    return 0;
}