Issue with Firebase Storage & Database - swift

Question

I'm having an app, with UpdateProfileViewController (iOS app, written in Swift). I'm using Firebase storage and Database as backend. The problem that I'm facing is that I have 2 images that need to be uploaded to the Firebase storage, then get the download URL and enter it in the database for that particular user. Now, I'm facing 3 problems.
The downloadURL method should return a URL pointing to the uploaded image in the storage and assign it to the variable storageHeaderDownloadedURL and the other one is headerImgDownloadedURL (those should be the header and the profile images).
I want to update all of the fields despite of the fact if the user changed something or not, just update the entire user profile.
I would like to be able to compress the the images and make them smaller in terms of size, not quality, so the users don't upload very big images.
Here's my entire code, I hope someone could help me out with that because I spent 2 days and I still cannot figure those things out:
#IBAction func savePressed(_ sender: UIBarButtonItem)
{
updateUserProfile()
}
func updateUserProfile ()
{
if let userID = FIRAuth.auth()?.currentUser?.uid
{
// Note: Storage references to profile images & profile headers folder
let storageUserProfileID = Storage.storage.profile_images.child(userID)
let storageUserHeaderID = Storage.storage.profile_headers.child(userID)
guard let imageProfile = profileImage.image else { return }
guard let headerImage = headerImage.image else { return }
var storageProfileDownloadedURL: String = ""
var storageHeaderDownloadedURL: String = ""
if let newProfileImage = UIImagePNGRepresentation(imageProfile), let newHeaderImage = UIImagePNGRepresentation(headerImage)
{
storageUserProfileID.put(newProfileImage, metadata: nil, completion: { (metadata, error) in
if error != nil
{
showAlert(title: "Oops!", msg: (error?.localizedDescription)!, actionButton: "OK", viewController: self)
return
}
// Get the URL from the storage
storageUserProfileID.downloadURL(completion: { (url, error) in
if error != nil
{
showAlert(title: "Oops!!!", msg: (error?.localizedDescription)!, actionButton: "OK", viewController: self)
return
}
if let profileImgDownloadedURL = url?.absoluteString
{
storageProfileDownloadedURL = profileImgDownloadedURL
}
})
})
storageUserHeaderID.put(newHeaderImage, metadata: nil, completion: { (metadata, error) in
if error != nil
{
showAlert(title: "Oops!", msg: (error?.localizedDescription)!, actionButton: "OK", viewController: self)
return
}
// Get the URL from the storage
storageUserHeaderID.downloadURL(completion: { (url, error) in
if error != nil
{
showAlert(title: "Oops!!!", msg: (error?.localizedDescription)!, actionButton: "OK", viewController: self)
return
}
else
{
if let headerImgDownloadedURL = url?.absoluteString
{
storageHeaderDownloadedURL = headerImgDownloadedURL
}
}
})
})
//Note: Update the info for that user in Database
}
guard let newDisplayName = self.displayNameTextField.text else { return }
guard let newLocation = self.locationTextField.text else { return }
guard let newDescription = self.bioTextField.text else { return }
guard let newWebsite = self.websiteTextField.text else { return }
guard let newBirthday = self.birthdayTextField.text else { return }
let newUpdatedUserDictionary = ["imageProfile": storageProfileDownloadedURL,
"imageHeader" : storageHeaderDownloadedURL,
"description" : newDescription,
"location": newLocation,
"displayName": newDisplayName,
"website": newWebsite,
"birthday": newBirthday,
]
Database.dataService.updateUserProfile(uid: userID, user: newUpdatedUserDictionary)
print("Successfully updated!")
showAlert(title: "Profile updated", msg: "YAASS", actionButton: "OK", viewController: self)
}
}