getting ALAssets from photos library iOS - objective-c

Question

I am trying to get the time, date and location from a movie i took on my iPhone/iPad This is the code i used
//i get the video picked and then save it to app but i think i am getting the movie's asset data before i save it.
- (void) imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{ NSError *error;
else if (picker.sourceType ==UIImagePickerControllerSourceTypePhotoLibrary) {
NSURL * movieURL = [info valueForKey:UIImagePickerControllerMediaURL] ;
ALAssetsLibrary* assetslibrary = [[ALAssetsLibrary alloc] init];
[assetslibrary assetForURL:movieURL
resultBlock:^(ALAsset*asset) {
NSDate *myDate = [asset valueForProperty:ALAssetPropertyDate];
NSLog(#"Date: %#", myDate);
} failureBlock:^(NSError *error) {
NSLog(#"Error");
}];
NSData * movieData = [NSData dataWithContentsOfURL:movieURL];
NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [documentPaths objectAtIndex:0];
NSString *slash = [documentsDirectory stringByAppendingPathComponent:#"/"];
NSString *documentsDirectory2 = [slash stringByAppendingPathComponent:self.user.text];
NSString *documentsDirectory21 = [documentsDirectory2 stringByAppendingPathComponent:#"/Movie"];
if (![[NSFileManager defaultManager] fileExistsAtPath:documentsDirectory21])
[[NSFileManager defaultManager] createDirectoryAtPath:documentsDirectory21 withIntermediateDirectories:NO attributes:nil error:&error];
NSString *fullPath = [documentsDirectory21 stringByAppendingPathComponent:[[self imageNameTextField]text]];
fullPath = [fullPath stringByAppendingFormat:#".mp4"];
[ movieData writeToFile:fullPath atomically:YES];
}
however myDate is logged as null
what am i doing wrong
I just tried this code also (added 10/11)
CGImageSourceRef source = CGImageSourceCreateWithURL( (CFURLRef)movieURL, NULL);
NSDictionary* metadata = (NSDictionary *)CFBridgingRelease(CGImageSourceCopyPropertiesAtIndex(source,0,NULL));
NSLog(#"image data %#", metadata);
but still metadata is null;
I read that videos don't have the same metadata as images. if this is true then how do I access the video metadata since I can see data tied to the video in photos.
any help would be greatly appreciated.
I have tried everything I could find on the internet to help me do this but nothing seems to work.
When I log my movieURL this is what I get
2016-10-13 09:58:51.045271 my little world app[2641:1388034] movieURL;file:///private/var/mobile/Containers/Data/Application/22A178E5-74C4- 48EF-B487-5E01321508AD/tmp/trim.04F0AC8A-2960-464D-8670-7E79662EAB9B.MOV
So since it is in a temporary file can I not get the metadata.
Does the Metadata exits in the movies NSData and can I get it from that?
I am pulling my hair out.

Answer 1

So I figured this out here is the code
- (void) imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
if (picker.sourceType ==UIImagePickerControllerSourceTypePhotoLibrary) {
NSURL * movieURL = [info valueForKey:UIImagePickerControllerMediaURL] ;
[self getMediaName:nil url:[info objectForKey:UIImagePickerControllerReferenceURL]];
}
}
- (void)getMediaName:(UIImage*)originalImage url:(NSURL*)url {
#try {
ALAssetsLibraryAssetForURLResultBlock resultblock = ^(ALAsset *asset) {
if (asset == nil) return;
ALAssetRepresentation *assetRep = [asset defaultRepresentation];
NSString *fileName = [assetRep filename];
NSDate *myDate = [asset valueForProperty:ALAssetPropertyDate];
NSDateFormatter *dateFormatter=[[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"MM-dd-yyyy"];
NSLog(#"%#",[dateFormatter stringFromDate:myDate]);
ALAssetsLibraryAccessFailureBlock failureblock = ^(NSError *error) {
};
ALAssetsLibrary *library = [ALAssetsLibrary new];
[library assetForURL:url resultBlock:resultblock failureBlock:failureblock];
}
#catch (NSException *exception) {
}
}
you can use any valueForProperty