//
//  Line.swift
//  VDS
//
//  Created by Nadigadda, Sumanth on 24/03/23.
//

import Foundation
import UIKit
import VDSCoreTokens

/// A line visually separates content sections or elements in lists, tables and layouts to indicate content hierarchy.
@objcMembers
@objc(VDSLine)
open class Line: View {
    
    //--------------------------------------------------
    // 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: - Enums
    //--------------------------------------------------
    /// Enum used to describe the style the line that will be displayed.
    public enum Style: String, CaseIterable {
        case primary, secondary
    }
    
    /// Enum used to describe the orientation that will be displayed.
    public enum Orientation: String, CaseIterable {
        case horizontal, vertical
    }
    
    //--------------------------------------------------
    // MARK: - Public Properties
    //--------------------------------------------------
    /// Style of the line that will be displayed.
    open var style: Style = .primary { didSet { setNeedsUpdate() } }
    
    /// Allows to render the line vertically.
    open var orientation: Orientation = .horizontal { didSet { setNeedsUpdate() } }
    
    /// The natural size for the receiving view, considering only properties of the view itself.
    open override var intrinsicContentSize: CGSize {
        if orientation == .vertical {
            return .init(width: lineWidth, height: bounds.height)
        } else {
            return .init(width: bounds.width, height: lineWidth)
        }
    }
        
    //--------------------------------------------------
    // MARK: - Configuration
    //--------------------------------------------------
    /// Width of the line.
    public let lineWidth: CGFloat = 1.0
    
    /// Line Color for current Style and Surface.
    open var lineColor: UIColor { lineViewColorConfiguration.getColor(self) }

    /// Color configuration use for text color.  This is a configuration that will provide a color based
    /// of local properties such as style and surface.
    open var lineViewColorConfiguration: AnyColorable = {
        let config = KeyedColorConfiguration<Line, Style>(keyPath: \.style)
        config.setSurfaceColors(VDSColor.elementsPrimaryOnlight, VDSColor.elementsPrimaryOndark, forKey: .primary)
        config.setSurfaceColors(VDSColor.elementsLowcontrastOnlight, VDSColor.elementsLowcontrastOndark, forKey: .secondary)
        return config.eraseToAnyColorable()
    }()
        
    //--------------------------------------------------
    // MARK: - Overrides
    //--------------------------------------------------
    /// Called once when a view is initialized and is used to Setup additional UI or other constants and configurations.
    open override func setup() {
        super.setup()
    }
    
    /// Used to make changes to the View based off a change events or from local properties.
    open override func updateView() {
        super.updateView()

        setNeedsDisplay()
    }
    
    /// Resets to default settings.
    open override func reset() {
        super.reset()
        style = .primary
        orientation = .horizontal
    }
    
    open override func draw(_ rect: CGRect) {
        guard let context = UIGraphicsGetCurrentContext() else { return }
       
        context.setStrokeColor(lineColor.cgColor)
        context.setLineWidth(lineWidth)
       
        if orientation == .horizontal {
            context.move(to: CGPoint(x: 0, y: rect.height / 2))
            context.addLine(to: CGPoint(x: rect.width, y: rect.height / 2))
        } else {
            context.move(to: CGPoint(x: rect.width / 2, y: 0))
            context.addLine(to: CGPoint(x: rect.width / 2, y: rect.height))
        }
       
        context.strokePath()
    }

}