//
//  BreadcrumbItem.swift
//  VDS
//
//  Created by Kanamarlapudi, Vasavi on 05/03/24.
//

import Foundation
import UIKit
import VDSCoreTokens
import Combine

/// A Breadcrumb Item contains href(link) and selected flag.
/// Breadcrumb links to its respective page if it is not disabled.
/// Breadcrumb contains text with a separator by default, highlights text in bold without a separator if selected.
@objcMembers
@objc (VDSBreadcrumbItem)
open class BreadcrumbItem: ButtonBase {
   
    //--------------------------------------------------
    // 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 Properties
    //--------------------------------------------------
    /// TextStyle used on the titleLabel.
    open override var textStyle: TextStyle { isSelected ? TextStyle.boldBodySmall : TextStyle.bodySmall }
            
    /// UIColor used on the titleLabel text.
    open override var textColor: UIColor {
        textColorConfiguration.getColor(self)
    }
        
    /// Determines if a slash is predended or not.
    open var hideSlash: Bool = false { didSet { setNeedsUpdate() } }
    
    private var slashText = "/ "
    
    open override var textAttributes: [any LabelAttributeModel]? {
        hideSlash
        ? nil
        : [ColorLabelAttribute(location: 0, 
                               length: 1,
                               color: surface == .light ? VDSColor.elementsPrimaryOnlight : VDSColor.elementsPrimaryOndark),
           TextStyleLabelAttribute(location: 0,
                                    length: 1,
                                    textStyle: .bodySmall)
        ]
    }
    
    //--------------------------------------------------
    // MARK: - Private Properties
    //--------------------------------------------------
    private var textColorConfiguration = ControlColorConfiguration().with {
        $0.setSurfaceColors(VDSColor.elementsPrimaryOnlight, VDSColor.elementsPrimaryOndark, forState: .normal)
        $0.setSurfaceColors(VDSColor.interactiveActiveOnlight, VDSColor.interactiveActiveOndark, forState: .highlighted)
        $0.setSurfaceColors(VDSColor.elementsPrimaryOnlight, VDSColor.elementsPrimaryOndark, forState: .selected)
    }
          
    //--------------------------------------------------
    // MARK: - Overrides
    //--------------------------------------------------
    open override func setDefaults() {
        super.setDefaults()
        isAccessibilityElement = true
        accessibilityTraits = .link
        
        titleLabel?.numberOfLines = 0
        titleLabel?.lineBreakMode = .byWordWrapping
        contentHorizontalAlignment = .left
        
        bridge_accessibilityHintBlock = { [weak self] in
            guard let self else { return "" }
            return !isEnabled ? "" : "Double tap to open."
        }
        
        bridge_accessibilityLabelBlock = {  [weak self] in
            guard let self else { return "" }
            return text
        }
    }

    /// Used to make changes to the View based off a change events or from local properties.
    open override func updateView() {
        
        //clear the arrays holding actions
        accessibilityCustomActions = []
        if let text, !text.isEmpty {
            var updatedText = text
            if updatedText.hasPrefix(slashText) && hideSlash {
                updatedText = String(updatedText.dropFirst(slashText.count))
            } else if !hideSlash, !updatedText.hasPrefix(slashText) {
                updatedText = slashText + updatedText
            }
            
            //create the primary string
            let mutableText = NSMutableAttributedString.mutableText(for: updatedText,
                                                                    textStyle: textStyle,
                                                                    useScaledFont: useScaledFont,
                                                                    textColor: textColor,
                                                                    alignment: titleLabel?.textAlignment ?? .center,
                                                                    lineBreakMode: titleLabel?.lineBreakMode ?? .byTruncatingTail)
            
            //apply any attributes
            if let attributes = textAttributes {
                mutableText.apply(attributes: attributes)
            }
            
            //set the attributed text
            setAttributedTitle(mutableText, for: .normal)
            setAttributedTitle(mutableText, for: .highlighted)
            invalidateIntrinsicContentSize()
        } else {
            setAttributedTitle(nil, for: .normal)
            setAttributedTitle(nil, for: .highlighted)
            titleLabel?.text = nil
        }

    }
}