//
//  LabelSystemImageLabelAttribute.swift
//  VDS
//
//  Created by Matt Bruce on 10/4/22.
//

import Foundation
import UIKit

public struct ImageLabelAttribute: AttachmentLabelAttributeModel {
    //--------------------------------------------------
    // MARK: - Enums
    //--------------------------------------------------
    /// Enum used to describe the type of error that can occur.
    public enum Error: Swift.Error {
        case bundleNotFound
        case imageNotFound(String)
        case imageNotSet
    }
    
    //--------------------------------------------------
    // MARK: - Public Properties
    //--------------------------------------------------
    public var id = UUID()
    public var location: Int
    public var length: Int = 1
    public var imageName: String?
    public var image: UIImage?
    public var frame: CGRect?
    public var tintColor: UIColor?
    public var accessibleText: String?

    //--------------------------------------------------
    // MARK: - Equatable
    //--------------------------------------------------
    public static func == (lhs: ImageLabelAttribute, rhs: ImageLabelAttribute) -> Bool {
        lhs.isEqual(rhs)
    }
    
    public func isEqual(_ equatable: ImageLabelAttribute) -> Bool {
        return id == equatable.id && range == equatable.range && imageName == equatable.imageName
    }

    public init(id: UUID = UUID(), location: Int, imageName: String? = nil, image: UIImage? = nil, frame: CGRect? = nil, tintColor: UIColor? = nil, accessibleText: String? = nil) {
        self.id = id
        self.location = location
        self.imageName = imageName
        self.image = image
        self.frame = frame
        self.tintColor = tintColor
        self.accessibleText = accessibleText
    }
    
    //--------------------------------------------------
    // MARK: - Private Methods
    //--------------------------------------------------
    private func imageAttachment(image: UIImage) -> NSTextAttachment {
        let attachment = NSTextAttachment()
        if let accessibleText {
            attachment.accessibilityLabel = accessibleText
        } else {
            attachment.accessibilityLabel = " "
        }
        attachment.image = tintColor != nil ? image.withTintColor(tintColor!) : image
        if let frame {
            attachment.bounds = frame
        }
        return attachment
    }
    
    //--------------------------------------------------
    // MARK: - Public Methods
    //--------------------------------------------------
    public func getAttachment() throws -> NSTextAttachment {
        
        //get a local asset
        if let imageName {
            guard let image =  BundleManager.shared.image(for: imageName) else {
                throw Error.imageNotFound(imageName)
            }
            
            return imageAttachment(image: image)
            
        } //get from set image
        else if let image {
            return imageAttachment(image: image)
            
        } else {
            throw Error.imageNotSet
        }
        
    }
}