Privado-iOS/iOS/Privado/Sources/Flows/ServersFlow/Submodules/UpgradeWarning/View/UpgradeWarningView.swift

//
//  UpgradeWarningView.swift
//  PrivadoVPN
//
//  Created by Zhandos Bolatbekov on 25.02.2021.
//  Copyright © 2021 Privado LLC. All rights reserved.
//

import UIKit

protocol UpgradeWarningViewOutput: AnyObject {
    func didTapUpgradeButton()
}

final class UpgradeWarningView: UIView {
    
    private enum Constants {
        enum Color {
            static let background = UIColor(rgb: 0x000424).withAlphaComponent(0.9)
            static let bodyText = UIColor(rgb: 0x7a85be)
            static let headlineText = UIColor.white
            
            static let buttonText = UIColor.white
            static let buttonBackground = UIColor(rgb: 0x2ad899)
        }
        enum Geometry {
            static let closeButtonSize = CGSize(width: 32, height: 32)
            static let closeButtonTop: CGFloat = 13
            static let closeButtonRight: CGFloat = 20
            static let bodyCenterYOffset: CGFloat = -37
            static let buttonHeight: CGFloat = 60
            static let buttonTop: CGFloat = 52
            static let commonIndent: CGFloat = 32
            static let headlineBottom: CGFloat = 16
        }
        enum Font {
            static let headline = UIFont(name: "SFProText-Light", size: 30) ?? .systemFont(ofSize: 30, weight: .light)
            static let body = UIFont(name: "SFProText-Regular", size: 21.3) ?? .systemFont(ofSize: 21.3, weight: .regular)
            static let buttonText = UIFont(name: "Roboto-Black", size: 21.3) ?? .systemFont(ofSize: 21.3, weight: .semibold)
        }
        enum LocalizedString {
            static let headline = "upgradeWarning.headline"
            static let body = "upgradeWarning.body"
            static let actionButton = "upgradeWarning.button"
        }
        static let buttonImageName = "close_rounded"
    }
    
    private let output: UpgradeWarningViewOutput
    
    // MARK: - Init
    
    init(output: UpgradeWarningViewOutput) {
        self.output = output
        super.init(frame: .zero)
        self.configureUI()
    }
    
    required init?(coder: NSCoder) { nil }
    
    // MARK: - Private
    
    private func configureUI() {
        self.translatesAutoresizingMaskIntoConstraints = false
        self.backgroundColor = Constants.Color.background
        
        let closeButton = self.initializeCloseButton()
        NSLayoutConstraint.activate([
            closeButton.topAnchor.constraint(equalTo: self.topAnchor, constant: Constants.Geometry.closeButtonTop),
            closeButton.rightAnchor.constraint(equalTo: self.rightAnchor, constant: -Constants.Geometry.closeButtonRight),
            closeButton.heightAnchor.constraint(equalToConstant: Constants.Geometry.closeButtonSize.height),
            closeButton.widthAnchor.constraint(equalToConstant: Constants.Geometry.closeButtonSize.width)
        ])
        
        let bodyLabel = self.initializeBodyLabel()
        NSLayoutConstraint.activate([
            bodyLabel.centerYAnchor.constraint(equalTo: self.centerYAnchor),
            bodyLabel.leadingAnchor.constraint(equalTo: self.leadingAnchor, constant: Constants.Geometry.commonIndent),
            bodyLabel.trailingAnchor.constraint(equalTo: self.trailingAnchor, constant: -Constants.Geometry.commonIndent)
        ])
        
        let headlineLabel = self.initializeHeadlineLabel()
        NSLayoutConstraint.activate([
            headlineLabel.bottomAnchor.constraint(equalTo: bodyLabel.topAnchor,
                                                  constant: -Constants.Geometry.headlineBottom),
            headlineLabel.leftAnchor.constraint(equalTo: self.leftAnchor, constant: Constants.Geometry.commonIndent),
            headlineLabel.rightAnchor.constraint(equalTo: self.rightAnchor, constant: -Constants.Geometry.commonIndent)
        ])
        
        let button = self.initializeActionButton()
        NSLayoutConstraint.activate([
            button.topAnchor.constraint(equalTo: bodyLabel.bottomAnchor, constant: Constants.Geometry.buttonTop),
            button.leadingAnchor.constraint(equalTo: self.leadingAnchor, constant: Constants.Geometry.commonIndent),
            button.trailingAnchor.constraint(equalTo: self.trailingAnchor, constant: -Constants.Geometry.commonIndent),
            button.heightAnchor.constraint(equalToConstant: Constants.Geometry.buttonHeight)
        ])
    }
    
    private func initializeHeadlineLabel() -> UILabel {
        let label = UILabel()
        label.translatesAutoresizingMaskIntoConstraints = false
        label.numberOfLines = 0
        label.textColor = Constants.Color.headlineText
        label.font = Constants.Font.headline
        label.textAlignment = .center
        label.text = NSLocalizedString(Constants.LocalizedString.headline, comment: "You’ve selected a premium server.")
        self.addSubview(label)
        return label
    }
    
    private func initializeBodyLabel() -> UILabel {
        let label = UILabel()
        label.translatesAutoresizingMaskIntoConstraints = false
        label.font = Constants.Font.body
        label.textAlignment = .center
        label.textColor = Constants.Color.bodyText
        label.text = NSLocalizedString(Constants.LocalizedString.body, comment: "Upgrade now to access additional worldwide servers!")
        label.numberOfLines = 0
        self.addSubview(label)
        return label
    }
    
    private func initializeActionButton() -> UIView {
        let button = UIButton(frame: .zero)
        button.translatesAutoresizingMaskIntoConstraints = false
        
        button.layer.cornerRadius = Constants.Geometry.buttonHeight / 2
        button.clipsToBounds = true
    
        button.backgroundColor = Constants.Color.buttonBackground
        button.setTitleColor(Constants.Color.buttonText, for: .normal)
        button.titleLabel?.font = Constants.Font.buttonText
        button.setTitle(NSLocalizedString(Constants.LocalizedString.actionButton, comment: "UPGRADE"), for: .normal)
        button.addTarget(self, action: #selector(self.onActionButtonTouch), for: .touchUpInside)
        self.addSubview(button)
        return button
    }
    
    private func initializeCloseButton() -> UIButton {
        let icon = UIImage(named: Constants.buttonImageName)?.resizeImage(targetSize: Constants.Geometry.closeButtonSize)
        let button = UIButton()
        button.translatesAutoresizingMaskIntoConstraints = false
        button.setImage(icon, for: .normal)
        button.addTarget(self, action: #selector(self.didTapClose), for: .touchUpInside)
        self.addSubview(button)
        return button
    }
    
    
    @objc
    private func didTapClose() {
        self.isHidden = true
    }
    
    @objc
    private func onActionButtonTouch() {
        self.isHidden = true
        self.output.didTapUpgradeButton()
    }
}