MealViewController.swift

//
//  MealViewController.swift
//  FoodTracker
//
//  Created by Apurv Pandey on 09/06/16.
//  Copyright © 2016 Apurv Pandey. All rights reserved.
//

import UIKit

class MealViewController: UIViewController, UITextFieldDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
    // MARK: Properties
    
    @IBOutlet weak var nameTextField: UITextField!
    @IBOutlet weak var photoImageView: UIImageView!
    @IBOutlet weak var ratingControl: RatingControl!
    @IBOutlet weak var saveButton: UIBarButtonItem!
    
    @IBAction func saveThisMeal(sender: AnyObject) {
        self.dismissViewControllerAnimated(true) { 
            let name = self.nameTextField.text ?? ""
            let photo = self.photoImageView.image
            let rating = self.ratingControl.rating
            
            // Set the meal to be passed to MealListTableViewController after the unwind segue.
            self.meal = Meal(name: name, photo: photo, rating: rating)
            NSNotificationCenter.defaultCenter().postNotificationName(MEALS_UPDATED, object: nil, userInfo: ["meal" : self.meal!])
        }
    }
    
    /*
     This value is either passed by `MealTableViewController` in `prepareForSegue(_:sender:)`
     or constructed as part of adding a new meal.
     */
    var meal: Meal?
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Handle the text field’s user input through delegate callbacks.
        nameTextField.delegate = self
        
        // Enable the Save button only if the text field has a valid Meal name.
        checkValidMealName()
    }
    
    // MARK: UITextFieldDelegate
    
    func textFieldShouldReturn(textField: UITextField) -> Bool {
        // Hide the keyboard.
        textField.resignFirstResponder()
        return true
    }
    
    func textFieldDidEndEditing(textField: UITextField) {
        checkValidMealName()
        navigationItem.title = textField.text
    }
    
    func textFieldDidBeginEditing(textField: UITextField) {
        // Disable the Save button while editing.
        saveButton.enabled = false
    }
    
    func checkValidMealName() {
        // Disable the Save button if the text field is empty.
        let text = nameTextField.text ?? ""
        saveButton.enabled = !text.isEmpty
    }
    
    // MARK: UIImagePickerControllerDelegate
    
    func imagePickerControllerDidCancel(picker: UIImagePickerController) {
        // Dismiss the picker if the user canceled.
        dismissViewControllerAnimated(true, completion: nil)
    }
    
    func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
        // The info dictionary contains multiple representations of the image, and this uses the original.
        let selectedImage = info[UIImagePickerControllerOriginalImage] as! UIImage
        
        // Set photoImageView to display the selected image.
        photoImageView.image = selectedImage
        
        // Dismiss the picker.
        dismissViewControllerAnimated(true, completion: nil)
    }
    
    // MARK: Navigation
    @IBAction func cancel(sender: UIBarButtonItem) {
        dismissViewControllerAnimated(true, completion: nil)
    }
    
    // This method lets you configure a view controller before it's presented.
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if (sender as! UIBarButtonItem) == saveButton {
            let name = nameTextField.text ?? ""
            let photo = photoImageView.image
            let rating = ratingControl.rating
            
            // Set the meal to be passed to MealListTableViewController after the unwind segue.
            meal = Meal(name: name, photo: photo, rating: rating)
        }
    }
    
    // MARK: Actions
    
    @IBAction func selectImageFromPhotoLibrary(sender: UITapGestureRecognizer) {
        // Hide the keyboard.
        nameTextField.resignFirstResponder()
        
        // UIImagePickerController is a view controller that lets a user pick media from their photo library.
        let imagePickerController = UIImagePickerController()
        
        // Only allow photos to be picked, not taken.
        imagePickerController.sourceType = .PhotoLibrary
        
        // Make sure ViewController is notified when the user picks an image.
        imagePickerController.delegate = self
        
        presentViewController(imagePickerController, animated: true, completion: nil)
    }
 
  /*  @IBAction func segueForUnwindingToViewController(toViewController: MealTableViewController, fromViewController: MealViewController)  {
        
        dismissViewControllerAnimated(true, completion: nil)
    }*/
}