mvm_core_ui/MVMCoreUI/BaseClasses/TextView.swift

//
//  TextView.swift
//  MVMCoreUI
//
//  Created by Kevin Christiano on 4/1/20.
//  Copyright © 2020 Verizon Wireless. All rights reserved.
//

import UIKit


@objc open class TextView: UITextView, UITextViewDelegate {
    //--------------------------------------------------
    // MARK: - Properties
    //--------------------------------------------------
    
    open var model: MoleculeModelProtocol?
    
    private var initialSetupPerformed = false
    
    /// Set to true to hide the blinking textField cursor.
    public var hideBlinkingCaret = false
    
    weak var bottomLine: SeparatorView?
    
    public var placeholderFont: UIFont = MFStyler.fontRegularMicro() {
        didSet {
            if text.isEmpty {
                font = placeholderFont
            }
        }
    }
    
    public var placeholder: String = "" {
        didSet {
            if text.isEmpty {
                text = placeholder
            }
        }
    }
    
    public var placeholderTextColor: UIColor = .mvmCoolGray3
    
    public var displaysPlaceholder = false
    
    private(set) var textStore: String = ""
    
    public override var text: String! {
        didSet {
            if displaysPlaceholder && text.isEmpty {
                text = placeholder
                textColor = placeholderTextColor
            } else {
                textColor = .mvmBlack
            }
        }
    }
    
    private(set) var textFont: UIFont = MFStyler.fontB2()!
    
    public override var font: UIFont? {
        didSet {
            if displaysPlaceholder && text.isEmpty {
                font = placeholderFont
            } else {
                textColor = .mvmBlack
            }
        }
    }
    
    //--------------------------------------------------
    // MARK: - Delegate
    //--------------------------------------------------
    
    /// Holds a reference to the delegating class so this class can internally influence the TextField behavior as well.
    public weak var didDeleteDelegate: TextFieldDidDeleteProtocol?
    
    /// If you're using a ViewController, you must set this to it
    public weak var uiTextViewDelegate: UITextViewDelegate? {
        get { return delegate }
        set { delegate = newValue }
    }
    
    //--------------------------------------------------
    // MARK: - Constraint
    //--------------------------------------------------
    
    public var heightConstraint: NSLayoutConstraint?
    
    //--------------------------------------------------
    // MARK: - Initialization
    //--------------------------------------------------
    
    public override init(frame: CGRect, textContainer: NSTextContainer?) {
        super.init(frame: .zero, textContainer: nil)
        initialSetup()
    }
    
    public convenience init() {
        self.init(frame: .zero, textContainer: nil)
    }
    
    public required init?(coder: NSCoder) {
        super.init(coder: coder)
        initialSetup()
    }
    
    convenience init(placeholderText: String, delegate: UITextViewDelegate?) {
        self.init(frame: .zero, textContainer: nil)
        self.delegate = delegate
        displaysPlaceholder = true
        self.placeholder = placeholderText
    }
    
    public func initialSetup() {
        
        if !initialSetupPerformed {
            tintColor = .mvmBlack
            initialSetupPerformed = true
            setupView()
        }
    }
    
    open override func caretRect(for position: UITextPosition) -> CGRect {
        
        if hideBlinkingCaret {
            return .zero
        }
        
        let caretRect = super.caretRect(for: position)
        return CGRect(origin: caretRect.origin, size: CGSize(width: 1, height: caretRect.height))
    }
    
    open override func deleteBackward() {
        super.deleteBackward()
        didDeleteDelegate?.textFieldDidDelete()
    }
    
    //--------------------------------------------------
    // MARK: - Observing Methods
    //--------------------------------------------------
    
    /// Executes on UITextView.textDidEndEditingNotification
    @objc open func dismissFieldInput() {
        
        resignFirstResponder()
    }
    
    //#pragma Mark UITextView Delegate methods forwarding
    @objc public func textViewShouldBeginEditing(_ textView: UITextView) -> Bool {
        
        return delegate?.textViewShouldBeginEditing?(textView) ?? true
    }
    
    @objc public func textViewDidBeginEditing(_ textView: UITextView) {
        
        delegate?.textViewDidBeginEditing?(textView)
    }
    
    @objc public func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
        
        return delegate?.textView?(textView, shouldChangeTextIn: range, replacementText: text) ?? true
    }
    
    @objc public func textViewDidChange(_ textView: UITextView) {
        
        delegate?.textViewDidChange?(textView)
    }
    
    @objc public func textViewShouldEndEditing(_ textView: UITextView) -> Bool {
        
        return delegate?.textViewShouldEndEditing?(textView) ?? true
    }
    
    @objc public func textViewDidEndEditing(_ textView: UITextView) {
        
        delegate?.textViewDidEndEditing?(textView)
    }
}

/// MARK:- MVMCoreViewProtocol
extension TextView: MVMCoreViewProtocol {
    
    open func updateView(_ size: CGFloat) { }
    
    /// Will be called only once.
    open func setupView() {
        
        translatesAutoresizingMaskIntoConstraints = false
        insetsLayoutMarginsFromSafeArea = false
        showsVerticalScrollIndicator = false
        showsHorizontalScrollIndicator = false
        clipsToBounds = true
        smartQuotesType = .no
        smartDashesType = .no
        smartInsertDeleteType = .no
        font = textFont
        layer.borderWidth = 1
        layer.borderColor = UIColor.mvmBlack.cgColor
        isEditable = true
    }
}

/// MARK:- MoleculeViewProtocol
extension TextView: MoleculeViewProtocol {
    
    open func set(with model: MoleculeModelProtocol, _ delegateObject: MVMCoreUIDelegateObject?, _ additionalData: [AnyHashable: Any]?) {
        self.model = model
        
        if let color = model.backgroundColor?.uiColor {
            backgroundColor = color
        }
        
        guard let model = model as? TextViewModel else { return }
        
        if let height = model.height {
            heightConstraint = heightAnchor.constraint(equalToConstant: height)
            heightConstraint?.isActive = true
        }
        
        isEditable = model.isEditable
        textAlignment = model.textAlignment
        textColor = model.textColor.uiColor
        text = model.text
        placeholder = model.placeholder
        uiTextViewDelegate = delegateObject?.uiTextViewDelegate
        MVMCoreUICommonViewsUtility.addDismissToolbar(to: self, delegate: delegateObject?.uiTextViewDelegate)
    }
    
    open func reset() {
        
        setNeedsDisplay()
        backgroundColor = .clear
        text = ""
    }
}