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

import Foundation
import UIKit
import VDSColorTokens
import VDSFormControlsTokens
import Combine

@objc(VDSEntryField)
open class EntryField: Control, Changeable {
    //--------------------------------------------------
    // MARK: - Enums
    //--------------------------------------------------
    public enum HelperTextPlacement: String, CaseIterable {
        case bottom, right
    }

    //--------------------------------------------------
    // 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: - Private Properties
    //--------------------------------------------------
    internal var stackView: UIStackView = {
        return UIStackView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
            $0.axis = .vertical
            $0.distribution = .fill
        }
    }()
                
    internal var containerView: UIView = {
        return UIView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
        }
    }()
    
    internal var containerStackView: UIStackView = {
        return UIStackView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
            $0.axis = .horizontal
            $0.distribution = .fillProportionally
            $0.alignment = .top
        }
    }()
    
    internal var controlContainerView: UIView = {
        return UIView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
        }
    }()
        
    //--------------------------------------------------
    // MARK: - Configuration Properties
    //--------------------------------------------------
    // Sizes are from InVision design specs.
    internal var containerSize: CGSize { CGSize(width: 45, height: 44) }
    
    internal let primaryColorConfiguration =  ViewColorConfiguration().with {
        $0.setSurfaceColors(VDSColor.interactiveDisabledOnlight, VDSColor.interactiveDisabledOndark, forDisabled: true)
        $0.setSurfaceColors(VDSColor.elementsPrimaryOnlight, VDSColor.elementsPrimaryOndark, forDisabled: false)
    }
    
    internal let secondaryColorConfiguration = ViewColorConfiguration().with {
        $0.setSurfaceColors(VDSColor.interactiveDisabledOnlight, VDSColor.interactiveDisabledOndark, forDisabled: true)
        $0.setSurfaceColors(VDSColor.elementsSecondaryOnlight, VDSColor.elementsSecondaryOndark, forDisabled: false)
    }

    internal var backgroundColorConfiguration = ControlColorConfiguration().with {
        $0.setSurfaceColors(VDSFormControlsColor.backgroundOnlight, VDSFormControlsColor.backgroundOndark, forState: .normal)
        $0.setSurfaceColors(VDSFormControlsColor.backgroundOnlight, VDSFormControlsColor.backgroundOndark, forState: .disabled)
        $0.setSurfaceColors(VDSColor.feedbackErrorBackgroundOnlight, VDSColor.feedbackErrorBackgroundOndark, forState: .error)
    }

    internal var borderColorConfiguration = ControlColorConfiguration().with {
        $0.setSurfaceColors(VDSFormControlsColor.borderOnlight, VDSFormControlsColor.borderOnlight, forState: .normal)
        $0.setSurfaceColors(VDSColor.interactiveDisabledOnlight, VDSColor.interactiveDisabledOndark, forState: .disabled)
        $0.setSurfaceColors(VDSColor.feedbackErrorOnlight, VDSColor.feedbackErrorOndark, forState: .error)
    }
    
    //--------------------------------------------------
    // MARK: - Public Properties
    //--------------------------------------------------
    public var onChangeSubscriber: AnyCancellable? {
        willSet {
            if let onChangeSubscriber {
                onChangeSubscriber.cancel()
            }
        }
    }

    open var titleLabel = Label().with {
        $0.setContentCompressionResistancePriority(.required, for: .vertical)
        $0.textPosition = .left
        $0.textStyle = .bodySmall
    }
    
    open var errorLabel = Label().with {
        $0.setContentCompressionResistancePriority(.required, for: .vertical)
        $0.textPosition = .left
        $0.textStyle = .bodySmall
    }
    
    open var helperLabel = Label().with {
        $0.setContentCompressionResistancePriority(.required, for: .vertical)
        $0.textPosition = .left
        $0.textStyle = .bodySmall
    }
    
    open var tooltipView: UIView?
    open var icon: Icon = Icon().with {
        $0.size = .small
    }
    
    open var labelText: String? { didSet { setNeedsUpdate() }}
    
    open var helperText: String? { didSet { setNeedsUpdate() }}
    
    open var showError: Bool = false { didSet { setNeedsUpdate() }}
    
    open override var state: UIControl.State {
        get {
            var state = super.state
            if showError {
                state.insert(.error)
            }
            return state
        }
    }
    
    open var errorText: String? { didSet { setNeedsUpdate() }}
            
    open var tooltipTitle: String? { didSet { setNeedsUpdate() }}
    
    open var tooltipContent: String? { didSet { setNeedsUpdate() }}
    
    open var transparentBackground: Bool = false { didSet { setNeedsUpdate() }}
    
    open var width: CGFloat? { didSet { setNeedsUpdate() }}
    
    open var maxLength: Int? { didSet { setNeedsUpdate() }}
    
    open var inputId: String? { didSet { setNeedsUpdate() }}
    
    open var value: AnyHashable? { didSet { setNeedsUpdate() }}
    
    open var defaultValue: AnyHashable? { didSet { setNeedsUpdate() }}
    
    open var required: Bool = false { didSet { setNeedsUpdate() }}
    
    open var readOnly: Bool = false { didSet { setNeedsUpdate() }}
    
    //--------------------------------------------------
    // MARK: - Constraints
    //--------------------------------------------------
    internal var heightConstraint: NSLayoutConstraint?
    internal var widthConstraint: NSLayoutConstraint?
        
    //--------------------------------------------------
    // MARK: - Lifecycle
    //--------------------------------------------------
    open override func setup() {
        super.setup()
                
        isAccessibilityElement = true
        accessibilityTraits = .button
        addSubview(stackView)
        
        //create the wrapping view
        heightConstraint = containerView.heightAnchor.constraint(greaterThanOrEqualToConstant: containerSize.height)
        heightConstraint?.isActive = true
        
        widthConstraint = containerView.widthAnchor.constraint(equalToConstant: 0)
     
        //get the container this is what is color
        //border, internal, etc...
        let container = getContainer()
        
        //add ContainerStackView
        //this is the horizontal stack that contains
        //the left, InputContainer, Icons, Buttons
        container.addSubview(containerStackView)
        containerStackView.pinToSuperView(.init(top: 12, left: 12, bottom: 12, right: 12))
    
        //add the view to add input fields
        containerStackView.addArrangedSubview(controlContainerView)
        containerStackView.addArrangedSubview(icon)

        stackView.addArrangedSubview(titleLabel)
        stackView.addArrangedSubview(container)
        stackView.addArrangedSubview(errorLabel)
        stackView.addArrangedSubview(helperLabel)

        stackView.setCustomSpacing(4, after: titleLabel)
        stackView.setCustomSpacing(8, after: container)
        stackView.setCustomSpacing(8, after: errorLabel)

        stackView
            .pinTop()
            .pinBottom()
            .pinLeading()
            .trailingAnchor.constraint(lessThanOrEqualTo: trailingAnchor).isActive = true

        titleLabel.textColorConfiguration = primaryColorConfiguration.eraseToAnyColorable()
        errorLabel.textColorConfiguration = primaryColorConfiguration.eraseToAnyColorable()
        helperLabel.textColorConfiguration = secondaryColorConfiguration.eraseToAnyColorable()
    }
    
    open func getContainer() -> UIView {
        return containerView
    }
    
    open override func reset() {
        super.reset()
        titleLabel.reset()
        errorLabel.reset()
        helperLabel.reset()
        
        titleLabel.textPosition = .left
        titleLabel.textStyle = .bodySmall
        errorLabel.textPosition = .left
        errorLabel.textStyle = .bodySmall
        helperLabel.textPosition = .left
        helperLabel.textStyle = .bodySmall

        labelText = nil
        helperText = nil
        showError = false
        errorText = nil
        tooltipTitle = nil
        tooltipContent = nil
        transparentBackground = false
        width = nil
        maxLength = nil
        inputId = nil
        value = nil
        defaultValue = nil
        required = false
        readOnly = false
    }
    
    //--------------------------------------------------
    // MARK: - State
    //--------------------------------------------------
    open override func updateView() {
        
        containerView.backgroundColor = backgroundColorConfiguration.getColor(self)
        containerView.layer.borderColor = borderColorConfiguration.getColor(self).cgColor
        containerView.layer.borderWidth = VDSFormControls.widthBorder
        containerView.layer.cornerRadius = VDSFormControls.borderradius

        updateTitleLabel()
        updateErrorLabel()
        updateHelperLabel()
        
        backgroundColor = surface.color
    }
    
    open func updateTitleLabel() {
               
        //update the local vars for the label since we no
        //long have a model
        var attributes: [any LabelAttributeModel] = []
        var updatedLabelText = labelText
        
        //dealing with the "Optional" addition to the text
        if let oldText = updatedLabelText, !required, !oldText.hasSuffix("Optional")  {
            if !disabled {
                let optionColorAttr = ColorLabelAttribute(location: oldText.count + 2,
                                                          length: 8,
                                                          color: VDSColor.elementsSecondaryOnlight)
                
                attributes.append(optionColorAttr)
            }
            updatedLabelText = "\(oldText)  Optional"
        }
        
        if let tooltipTitle, let tooltipContent {
            attributes.append(TooltipLabelAttribute(surface: surface, title: tooltipTitle, content: tooltipContent))
        }

        //set the titleLabel
        titleLabel.text = updatedLabelText
        titleLabel.attributes = attributes
        titleLabel.surface = surface
        titleLabel.disabled = disabled
        
    }
    
    open func updateErrorLabel(){
        if showError, let errorText {
            errorLabel.text = errorText
            errorLabel.surface = surface
            errorLabel.disabled = disabled
            errorLabel.isHidden = false
            icon.name = .error
            icon.color = VDSColor.paletteBlack
            icon.surface = surface
            icon.isHidden = disabled
        } else {
            icon.isHidden = true
            errorLabel.isHidden = true
        }
    }
    
    open func updateHelperLabel(){
        //set the helper label position
        if let helperText {
            helperLabel.text = helperText
            helperLabel.surface = surface
            helperLabel.disabled = disabled
            helperLabel.isHidden = false
        } else {
            helperLabel.isHidden = true
        }
    }
}