ViewController.swift

//
//  ViewController.swift
//  Project 06.2 - Hacking With Swift
//
//  Created by Thomas Kellough on 6/18/19.
//  Copyright © 2019 Thomas Kellough. All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        
        let label1 = UILabel()
        label1.translatesAutoresizingMaskIntoConstraints = false
        label1.backgroundColor = .red
        label1.text = "THESE"
        label1.sizeToFit()
        
        let label2 = UILabel()
        label2.translatesAutoresizingMaskIntoConstraints = false
        label2.backgroundColor = .cyan
        label2.text = "ARE"
        label2.sizeToFit()
        
        let label3 = UILabel()
        label3.translatesAutoresizingMaskIntoConstraints = false
        label3.backgroundColor = .yellow
        label3.text = "SOME"
        label3.sizeToFit()
        
        let label4 = UILabel()
        label4.translatesAutoresizingMaskIntoConstraints = false
        label4.backgroundColor = .green
        label4.text = "AWESOME"
        label4.sizeToFit()
        
        let label5 = UILabel()
        label5.translatesAutoresizingMaskIntoConstraints = false
        label5.backgroundColor = .orange
        label5.text = "LABELS"
        label5.sizeToFit()

        view.addSubview(label1)
        view.addSubview(label2)
        view.addSubview(label3)
        view.addSubview(label4)
        view.addSubview(label5)
        
        
//        OPTION 1: ----------------------------------------------------------------------------------------------------------------
//        let viewsDictionary = ["label1": label1, "label2": label2, "label3": label3, "label4": label4, "label5": label5, ]
//
//        for label in viewsDictionary.keys {
//            // H: means horizontal, | means "edge of view controller", [] around label are saying "put label here"
//            // Dictionary is used to match the string to the label
//            view.addConstraints(NSLayoutConstraint.constraints(
//                withVisualFormat: "H:|[\(label)]|",
//                options: [],
//                metrics: nil,
//                views: viewsDictionary)
//            )
//        }
//
//        // - is a space (10 points by default, can be customized)
//        // No pipe at the end, doesn't force last label to strech and will allow white space to be present below last label and bottom of screen
//        // -(>=10)- sets size of a space, note: you need the - before and after the size inside of ()
//        let metrics = ["labelHeight": 88]
//        view.addConstraints(NSLayoutConstraint.constraints(
//            withVisualFormat: "V:|[label1(labelHeight@999)]-[label2(label1)]-[label3(label1)]-[label4(label1)]-[label5(label1)]-(>=10)-|",
//            options: [],
//            metrics: metrics,
//            views: viewsDictionary)
//        )
        
        
        
//        OPTION 2: ----------------------------------------------------------------------------------------------------------------
        var previous: UILabel? // Used to set the top anchor, we need an optional since there is no previous label
        
        // Loops over each label and sets width to the same as our main view with a height of 88 points
        for label in [label1, label2, label3, label4, label5] {
//            label.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true ----- Removed for challenge part 1 & 2 - replaced below
            label.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor).isActive = true
            label.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor).isActive = true
//            label.heightAnchor.constraint(equalToConstant: 88).isActive = true ----- Removed for challenge part 3 - replaced below
            label.heightAnchor.constraint(equalTo: view.safeAreaLayoutGuide.heightAnchor, multiplier: 0.2, constant: 10).isActive = true
            
            // Allows top anchor to be set to bottom anchor of previous label
            if let previous = previous {
                label.topAnchor.constraint(equalTo: previous.bottomAnchor, constant: 10).isActive = true
            } else { // This else statement brings the top label down into the safe area
                label.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor, constant: 0).isActive = true
            }
            
            // Sets previous label
            previous = label
        }
    }

}