LitterReportViewController

import UIKit

class LitterReportViewController: UIViewController {
  // MARK: - Properties
  private let imagePickerController = UIImagePickerController()
  private var selectedImage: UIImage?

  // MARK: - Outlets
  @IBOutlet weak var imageView: UIImageView!
  @IBOutlet weak var addPhotoButton: UIButton!
  @IBOutlet weak var locationTextField: UITextField!
  @IBOutlet weak var submitButton: UIButton!

  // MARK: - Actions
  @IBAction func addPhotoButtonTapped(_ sender: Any) {
    showImagePicker()
  }

  @IBAction func submitButtonTapped(_ sender: Any) {
    guard let location = locationTextField.text, !location.isEmpty else {
      showMissingLocationAlert()
      return
    }

    guard let image = selectedImage else {
      showMissingImageAlert()
      return
    }

    submitLitterReport(location: location, image: image)
  }

  // MARK: - Private
  private func showImagePicker() {
    imagePickerController.sourceType = .photoLibrary
    imagePickerController.delegate = self
    present(imagePickerController, animated: true)
  }

  private func showMissingLocationAlert() {
    let alertController = UIAlertController(title: "Missing Location",
                                            message: "Please enter the location of the litter.",
                                            preferredStyle: .alert)
    let okAction = UIAlertAction(title: "OK", style: .default)
    alertController.addAction(okAction)
    present(alertController, animated: true)
  }

  private func showMissingImageAlert() {
    let alertController = UIAlertController(title: "Missing Image",
                                            message: "Please add a photo of the litter.",
                                            preferredStyle: .alert)
    let okAction = UIAlertAction(title: "OK", style: .default)
    alertController.addAction(okAction)
    present(alertController, animated: true)
  }

  private func submitLitterReport(location: String, image: UIImage) {
    // TODO: Implement code to submit litter report
  }
}

// MARK: - UIImagePickerControllerDelegate
extension LitterReportViewController: UIImagePickerControllerDelegate {
  func imagePickerController(_ picker: UIImagePickerController,
                             didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
    selectedImage = info[.originalImage] as? UIImage
    imageView.image = selectedImage
    dismiss(animated: true)
  }
}

// MARK: - UINavigationControllerDelegate
extension LitterReportViewController: UINavigationControllerDelegate {
}