//
//  TextLink.swift
//  VDS
//
//  Created by Matt Bruce on 11/1/22.
//

import Foundation
import UIKit
import VDSColorTokens
import VDSFormControlsTokens
import Combine

@objc(VDSTextLink)
open class TextLink: ButtonBase {
    
    //--------------------------------------------------
    // MARK: - Private Properties
    //--------------------------------------------------
    private var lineHeightConstraint: NSLayoutConstraint?
    
    private var line = UIView().with {
        $0.translatesAutoresizingMaskIntoConstraints = false
    }

    //--------------------------------------------------
    // MARK: - Properties
    //--------------------------------------------------
    open var size: ButtonSize = .large { didSet { setNeedsUpdate() }}
        
    open override var availableSizes: [ButtonSize] { [.large, .small] }

    open override var textStyle: TextStyle {
        size == .large ? TextStyle.bodyLarge : TextStyle.bodySmall
    }
        
    /// UIColor used on the titleLabel text.
    open override var textColor: UIColor {
        textColorConfiguration.getColor(self)
    }
        
    private var textColorConfiguration = ControlColorConfiguration().with {
        $0.setSurfaceColors(VDSColor.elementsPrimaryOnlight, VDSColor.elementsPrimaryOndark, forState: .normal)
        $0.setSurfaceColors(VDSColor.interactiveDisabledOnlight, VDSColor.interactiveDisabledOndark, forState: .disabled)
        $0.setSurfaceColors(VDSColor.interactiveActiveOnlight, VDSColor.interactiveActiveOndark, forState: .highlighted)
    }
            
    private var height: CGFloat {
        switch size {
        case .large:
            return 44
        case .small:
            return 32
        }
    }

    //--------------------------------------------------
    // 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: - Public Methods
    //--------------------------------------------------
    open override func setup() {
        super.setup()
        isAccessibilityElement = true
        accessibilityTraits = .link
        
        if let titleLabel {
            addSubview(line)
            line.pinLeading(titleLabel.leadingAnchor)
            line.pinTrailing(titleLabel.trailingAnchor)
            line.pinTop(titleLabel.bottomAnchor)
            line.pinBottom(bottomAnchor, 0, .defaultHigh)
            lineHeightConstraint = line.height(constant: 1)
            lineHeightConstraint?.isActive = true
        }
    }

    /// Resets to default settings.
    open override func reset() {
        super.reset()
        shouldUpdateView = false
        text = nil
        size = .large
        accessibilityCustomActions = []
        isAccessibilityElement = true
        accessibilityTraits = .link
        shouldUpdateView = true
        setNeedsUpdate()
    }
    
    //--------------------------------------------------
    // MARK: - Overrides
    //--------------------------------------------------
    /// The natural size for the receiving view, considering only properties of the view itself.
    open override var intrinsicContentSize: CGSize {
        return titleLabel?.intrinsicContentSize ?? super.intrinsicContentSize
    }
    
    /// Used to make changes to the View based off a change events or from local properties.
    open override func updateView() {
        //need to set the properties so the super class
        //can render out the label correctly
        line.backgroundColor = textColor
        
        //always call last so the label is rendered
        super.updateView()
    }
}