//
//  LabelAttributeFont.swift
//  VDS
//
//  Created by Matt Bruce on 8/3/22.
//

import Foundation
import UIKit

public struct TypographicalStyleLabelAttribute: LabelAttributeModel {
    
    public func isEqual(_ equatable: TypographicalStyleLabelAttribute) -> Bool {
        return id == equatable.id
        && range == equatable.range
        && color == equatable.color
        && style == equatable.style
    }
    
    //--------------------------------------------------
    // MARK: - Properties
    //--------------------------------------------------
    public var id = UUID()
    public var location: Int
    public var length: Int
    public var style: TypographicalStyle
    public var color: UIColor
    public var textPosition: TextPosition
    public var lineBreakMode: NSLineBreakMode
    
    //--------------------------------------------------
    // MARK: - Initializer
    //--------------------------------------------------
    public init(location: Int, length: Int, style: TypographicalStyle, color: UIColor = .black, textPosition: TextPosition = .left, lineBreakMode: NSLineBreakMode = .byWordWrapping) {
        self.location = location
        self.length = length
        self.style = style
        self.color = color
        self.textPosition = textPosition
        self.lineBreakMode = lineBreakMode
    }
    
    public func setAttribute(on attributedString: NSMutableAttributedString) {
        attributedString.removeAttribute(.font, range: range)
        attributedString.removeAttribute(.foregroundColor, range: range)
        attributedString.addAttribute(.font, value: style.font, range: range)
        attributedString.addAttribute(.foregroundColor, value: color, range: range)
        setStyleAttributes(attributedString)
    }
    
    private func setStyleAttributes(_ attributedString: NSMutableAttributedString) {
        //set letterSpacing
        if style.letterSpacing > 0.0 {
            attributedString.removeAttribute(.kern, range: range)
            attributedString.addAttribute(.kern, value: style.letterSpacing, range: range)
        }
        
        //set lineHeight
        if style.lineHeight > 0.0 {
            let lineHeight = style.lineHeight
            let adjustment = lineHeight > style.font.lineHeight ? 2.0 : 1.0
            let baselineOffset = (lineHeight - style.font.lineHeight) / 2.0 / adjustment
            let paragraph = NSMutableParagraphStyle().with {
                $0.maximumLineHeight = lineHeight
                $0.minimumLineHeight = lineHeight
                $0.alignment = textPosition.textAlignment
                $0.lineBreakMode = lineBreakMode
            }
            attributedString.removeAttribute(.baselineOffset, range: range)
            attributedString.removeAttribute(.paragraphStyle, range: range)
            attributedString.addAttribute(.baselineOffset, value: baselineOffset, range: range)
            attributedString.addAttribute(.paragraphStyle, value: paragraph, range: range)
            
        } else if textPosition != .left {
            let paragraph = NSMutableParagraphStyle().with {
                $0.alignment = textPosition.textAlignment
                $0.lineBreakMode = lineBreakMode
            }
            attributedString.removeAttribute(.paragraphStyle, range: range)
            attributedString.addAttribute(.paragraphStyle, value: paragraph, range: range)
        }
    }
}