//
//  TextView.swift
//  VDS
//
//  Created by Matt Bruce on 2/29/24.
//

import Foundation
import UIKit
import Combine
import VDSCoreTokens

@objc(VDSTextView)
open class TextView: UITextView, ViewProtocol, Errorable {
    
    //--------------------------------------------------
    // MARK: - Initializers
    //--------------------------------------------------
    required public init() {
        super.init(frame: .zero, textContainer: nil)
        initialSetup()
    }
    
    public override init(frame: CGRect, textContainer: NSTextContainer?) {
        super.init(frame: frame, textContainer: textContainer)
        initialSetup()
    }
    
    public required init?(coder: NSCoder) {
        super.init(coder: coder)
        initialSetup()
    }

    //--------------------------------------------------
    // MARK: - Combine Properties
    //--------------------------------------------------
    /// Set of Subscribers for any Publishers for this Control.
    open var subscribers = Set<AnyCancellable>()

    //--------------------------------------------------
    // MARK: - Private Properties
    //--------------------------------------------------
    private var initialSetupPerformed = false
        
    //--------------------------------------------------
    // MARK: - Properties
    //--------------------------------------------------
    open var placeholder: String? {
        didSet {
            placeholderLabel.text = placeholder
        }
    }

    open var placeholderLabel = Label().with {
        $0.textColorConfiguration = ViewColorConfiguration().with {
            $0.setSurfaceColors(VDSColor.interactiveDisabledOnlight, VDSColor.interactiveDisabledOndark, forDisabled: true)
            $0.setSurfaceColors(VDSColor.elementsSecondaryOnlight, VDSColor.elementsSecondaryOndark, forDisabled: false)
        }.eraseToAnyColorable()
    }

    /// Key of whether or not updateView() is called in setNeedsUpdate()
    open var shouldUpdateView: Bool = true
    
    open var surface: Surface = .light { didSet { setNeedsUpdate() } }

    /// Array of LabelAttributeModel objects used in rendering the text.
    open var textAttributes: [any LabelAttributeModel]? { didSet { setNeedsUpdate() } }

    /// TextStyle used on the titleLabel.
    open var textStyle: TextStyle { .defaultStyle }

    /// Will determine if a scaled font should be used for the titleLabel font.
    open var useScaledFont: Bool = false { didSet { setNeedsUpdate() } }

    open var isEnabled: Bool = true { didSet { setNeedsUpdate() } }
    
    open var textColorConfiguration: AnyColorable = ViewColorConfiguration().with {
        $0.setSurfaceColors(VDSColor.interactiveDisabledOnlight, VDSColor.interactiveDisabledOndark, forDisabled: true)
        $0.setSurfaceColors(VDSColor.elementsPrimaryOnlight, VDSColor.elementsPrimaryOndark, forDisabled: false)
    }.eraseToAnyColorable(){ didSet { setNeedsUpdate() }}
    
    open var showError: Bool = false { didSet { setNeedsUpdate() } }
    
    open var errorText: String? { didSet { setNeedsUpdate() } }

    open override var textColor: UIColor? {
        get { textColorConfiguration.getColor(self) }
        set { }
    }
    
    override public var text: String! {
        get { super.text }
        set {
            super.text = newValue
            updateLabel()
        }
    }

    override public var textAlignment: NSTextAlignment {
        didSet {
            if textAlignment != oldValue {
                // Text alignment can be part of our paragraph style, so we may need to
                // re-style when changed
                placeholderLabel.textAlignment = textAlignment
                updateLabel()
            }
        }
    }

    //--------------------------------------------------
    // MARK: - Lifecycle
    //--------------------------------------------------
    open func initialSetup() {
        if !initialSetupPerformed {
            initialSetupPerformed = true
            backgroundColor = .clear
            translatesAutoresizingMaskIntoConstraints = false
            setup()
            setNeedsUpdate()
        }
    }
    
    open func setup() {
        let accessView = UIView(frame: .init(origin: .zero, size: .init(width: UIScreen.main.bounds.width, height: 44)))
        accessView.backgroundColor = .white
        accessView.addBorder(side: .top, width: 1, color: .lightGray)
        let done = UIButton(type: .system)
        done.setTitle("Done", for: .normal)
        done.translatesAutoresizingMaskIntoConstraints = false
        done.addTarget(self, action: #selector(doneButtonAction), for: .touchUpInside)
        accessView.addSubview(done)
        done.pinCenterY()
            .pinTrailing(16)
        inputAccessoryView = accessView
        
        addSubview(placeholderLabel)
        placeholderLabel.pinToSuperView()
    }
    
    @objc func doneButtonAction() {
        // Resigns the first responder status when 'Done' is tapped
        resignFirstResponder()
    }

    open func updateView() {
        updateLabel()
    }
    
    open func updateAccessibility() {
        if let errorText, showError {
            accessibilityLabel = "error, \(errorText)"
        } else {
            accessibilityLabel = nil
        }
    }

    open func reset() {
        shouldUpdateView = false
        surface = .light
        text = nil
        shouldUpdateView = true
        setNeedsUpdate()
    }
    
    open override func layoutSubviews() {
        super.layoutSubviews()
        placeholderLabel.preferredMaxLayoutWidth = textContainer.size.width - textContainer.lineFragmentPadding * 2
    }

    //--------------------------------------------------
    // MARK: - Accessibility
    //--------------------------------------------------
    open var accessibilityAction: ((TextView) -> Void)?

    open override var isAccessibilityElement: Bool {
        get {
            var block: AXBoolReturnBlock?
            
//            if #available(iOS 17, *) {
//                 block = isAccessibilityElementBlock
//            }
            
            if block == nil {
                block = bridge_isAccessibilityElementBlock
            }
            
            if let block {
                return block()
            } else {
                return super.isAccessibilityElement
            }
        }
        set {
            super.isAccessibilityElement = newValue
        }
    }

    open override var accessibilityLabel: String? {
        get {
            var block: AXStringReturnBlock?
//            if #available(iOS 17, *) {
//                 block = accessibilityLabelBlock
//            }
            
            if block == nil {
                block = bridge_accessibilityLabelBlock
            }

            if let block {
                return block()
            } else {
                return super.accessibilityLabel
            }
        }
        set {
            super.accessibilityLabel = newValue
        }
    }
    
    open override var accessibilityHint: String? {
        get {
            var block: AXStringReturnBlock?
//            if #available(iOS 17, *) {
//                 block = accessibilityHintBlock
//            }
            
            if block == nil {
                block = bridge_accessibilityHintBlock
            }

            if let block {
                return block()
            } else {
                return super.accessibilityHint
            }
        }
        set {
            super.accessibilityHint = newValue
        }
    }
    
    open override var accessibilityValue: String? {
        get {
            var block: AXStringReturnBlock?
            
//            if #available(iOS 17, *) {
//                block = accessibilityHintBlock
//            }
            
            if block == nil {
                block = bridge_accessibilityValueBlock
            }
            
            if let block{
                return block()
            } else {
                return super.accessibilityValue
            }
        }
        set {
            super.accessibilityValue = newValue
        }
    }
    
    open override func accessibilityActivate() -> Bool {
        guard isEnabled, isUserInteractionEnabled else { return false }
        
//        if #available(iOS 17, *) {
//            if let block = accessibilityAction {
//                block(self)
//                return true
//            } else if let block = accessibilityActivateBlock {
//                return block()
//                
//            } else if let block = bridge_accessibilityActivateBlock {
//                return block()
//                
//            } else {
//                return super.accessibilityActivate()
//                
//            }
//
//        } else {
            if let block = accessibilityAction {
                block(self)
                return true

            } else if let block = bridge_accessibilityActivateBlock {
                return block()
                
            } else {
                return super.accessibilityActivate()
                
            }
//        }
    }

    //--------------------------------------------------
    // MARK: - Private Methods
    //--------------------------------------------------
    private func updateLabel() {
        
        //clear the arrays holding actions
        accessibilityCustomActions = []
        if let text, !text.isEmpty {
            //create the primary string
            let mutableText = NSMutableAttributedString.mutableText(for: text,
                                                                    textStyle: textStyle,
                                                                    useScaledFont: useScaledFont,
                                                                    textColor: textColor!,
                                                                    alignment: textAlignment,
                                                                    lineBreakMode: .byWordWrapping)
            //apply any attributes
            if let attributes = textAttributes {
                mutableText.apply(attributes: attributes)
            }
            attributedText = mutableText
        } else {
            attributedText = nil
        }
        placeholderLabel.textStyle = textStyle
        placeholderLabel.isHidden = !text.isEmpty
        placeholderLabel.surface = surface
    }

}