vds_ios/VDS/Components/TextFields/InputField/InputField.swift

//
//  TextEntryField.swift
//  VDS
//
//  Created by Matt Bruce on 10/3/22.
//

import Foundation
import UIKit
import VDSTokens
import Combine

/// An input field is an input wherein a customer enters information. They typically appear in forms.
/// Specialized input fields capture credit card numbers, inline actions, passwords, phone numbers,
/// dates and security codes in their correct formats.
@objc(VDSInputField)
open class InputField: EntryFieldBase, UITextFieldDelegate {
    
    //--------------------------------------------------
    // MARK: - Initializers
    //--------------------------------------------------
    required public init() {
        super.init(frame: .zero)
    }
    
    public override init(frame: CGRect) {
        super.init(frame: .zero)
    }
    
    public required init?(coder: NSCoder) {
        super.init(coder: coder)
    }

    //--------------------------------------------------
    // MARK: - Enums
    //--------------------------------------------------
    /// Enum used to describe the input type.
    public enum FieldType: String, CaseIterable {
        case text, number, calendar, inlineAction, password, creditCard, tel, date, securityCode
    }

    //--------------------------------------------------
    // MARK: - Private Properties
    //--------------------------------------------------
     internal var inputFieldStackView: UIStackView = {
        return UIStackView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
            $0.axis = .horizontal
            $0.distribution = .fill
            $0.spacing = 12
        }
    }()
        
    internal var minWidthConstraint: NSLayoutConstraint?

    //--------------------------------------------------
    // MARK: - Public Properties
    //--------------------------------------------------
    /// Label to render the successText.
    open var successLabel = Label().with {
        $0.setContentCompressionResistancePriority(.required, for: .vertical)
        $0.textStyle = .bodySmall
    }
    
    /// UITextField shown in the InputField.
    open var textField = UITextField().with {
        $0.translatesAutoresizingMaskIntoConstraints = false
        $0.font = TextStyle.bodyLarge.font
    }
    
    /// Color configuration for the textField.
    open var textFieldTextColorConfiguration: AnyColorable = ViewColorConfiguration().with {
        $0.setSurfaceColors(VDSColor.interactiveDisabledOnlight, VDSColor.interactiveDisabledOndark, forDisabled: true)
        $0.setSurfaceColors(VDSColor.elementsPrimaryOnlight, VDSColor.elementsPrimaryOndark, forDisabled: false)
    }.eraseToAnyColorable()

    /// Representing the type of input.
    open var fieldType: FieldType = .text { didSet { setNeedsUpdate() } }

    var _showError: Bool = false
    /// Whether not to show the error.
    open override var showError: Bool {
        get { _showError }
        set {
            if !showSuccess && _showError != newValue {
                _showError = newValue
                setNeedsUpdate()
            }
        }
    }

    var _showSuccess: Bool = false
    /// Whether not to show the success.
    open var showSuccess: Bool {
        get { _showSuccess }
        set {
            if !showError && _showSuccess != newValue {
                _showSuccess = newValue
                setNeedsUpdate()
            }
        }
    }
        
    /// Override UIControl state to add the .error state if showSuccess is true and if showError is true.
    open override var state: UIControl.State {
        get {
            var state = super.state
            if showSuccess {
                state.insert(.success)
            }
            return state
        }
    }
    /// If given, this will be shown if showSuccess if true.
    open var successText: String? { didSet { setNeedsUpdate() } }
        
    /// Determines the placement of the helper text.
    open var helperTextPlacement: HelperTextPlacement = .bottom { didSet { setNeedsUpdate() } }

    //--------------------------------------------------
    // MARK: - Overrides
    //--------------------------------------------------
    /// Called once when a view is initialized and is used to Setup additional UI or other constants and configurations.
    open override func setup() {
        super.setup()
        
        minWidthConstraint = containerView.widthAnchor.constraint(greaterThanOrEqualToConstant: 0)
        minWidthConstraint?.isActive = true
        
        controlContainerView.addSubview(textField)
        textField
            .pinTop()
            .pinLeading()
            .pinTrailingLessThanOrEqualTo(nil, 0, .defaultHigh)
            .pinBottom(0, .defaultHigh)
        
        textField.heightAnchor.constraint(equalToConstant: 20).isActive = true
        textField
            .textPublisher
            .sink { [weak self] text in
                self?.value = text
                self?.sendActions(for: .valueChanged)
                
            }.store(in: &subscribers)
        
        stackView.addArrangedSubview(successLabel)
        stackView.setCustomSpacing(8, after: successLabel)
        
        successLabel.textColorConfiguration = primaryColorConfiguration.eraseToAnyColorable()
        
        backgroundColorConfiguration.setSurfaceColors(VDSColor.feedbackSuccessBackgroundOnlight, VDSColor.feedbackSuccessBackgroundOndark, forState: .success)
        borderColorConfiguration.setSurfaceColors(VDSColor.feedbackSuccessOnlight, VDSColor.feedbackSuccessOndark, forState: .success)

    }
    
    /// Resets to default settings.
    open override func reset() {
        super.reset()
        textField.text = ""
        textField.delegate = self
        
        successLabel.reset()
        successLabel.textStyle = .bodySmall
        
        fieldType = .text
        showSuccess = false
        successText = nil
        helperTextPlacement = .bottom
    }
    
    /// Container for the area in which the user interacts.
    open override func getContainer() -> UIView {
        inputFieldStackView.addArrangedSubview(containerView)
        return inputFieldStackView
    }

    /// Used to make changes to the View based off a change events or from local properties.
    open override func updateView() {
        super.updateView()
        
        textField.isEnabled = isEnabled
        textField.textColor = textFieldTextColorConfiguration.getColor(self)
        
        //show error or success
        if showError, let _ = errorText {
            successLabel.isHidden = true
            
        } else if showSuccess, let successText {
            successLabel.text = successText
            successLabel.surface = surface
            successLabel.isEnabled = isEnabled
            successLabel.isHidden = false
            errorLabel.isHidden = true
            icon.name = .checkmarkAlt
            icon.color = VDSColor.paletteBlack
            icon.surface = surface
            icon.isHidden = !isEnabled
        } else {
            icon.isHidden = true
            successLabel.isHidden = true
        }
                
        //set the width constraints
        if let width, width > fieldType.width  {
            widthConstraint?.constant = width
            widthConstraint?.isActive = true
            minWidthConstraint?.isActive = false
        } else {
            minWidthConstraint?.constant = fieldType.width
            widthConstraint?.isActive = false
            minWidthConstraint?.isActive = true
        }
    }
    
    open override func updateHelperLabel(){
        //remove first
        helperLabel.removeFromSuperview()
        
        super.updateHelperLabel()

        //set the helper label position
        if helperText != nil {
            if helperTextPlacement == .right {
                inputFieldStackView.spacing = 12
                inputFieldStackView.distribution = .fillEqually
                inputFieldStackView.addArrangedSubview(helperLabel)
            } else {
                inputFieldStackView.spacing = 0
                inputFieldStackView.distribution = .fill
                stackView.addArrangedSubview(helperLabel)
            }
        }
    }
    
}

extension InputField.FieldType {
    var width: CGFloat {
        switch self {
        case .inlineAction:
            return 102
        case .password:
            return 62.0
        case .creditCard:
            return 288.0
        case .tel:
            return 176.0
        case .date:
            return 114.0
        case .securityCode:
            return 88.0
        default:
            return 40.0
        }
    }
}