TypeWriterView.swift

//
//  TypeWriterView.swift
//
//  Created by Abdullah Kardaş on 10.01.2023.
//

import SwiftUI

struct TypeWriterView: View {
    @State var text: String = ""
    @State var isStop = false
    let finalText: String
    let font:Font
    let alignment:Alignment
    @State var animating = false
    var body: some View {
        VStack(alignment: .leading,spacing: 45) {
       
            Toggle(isOn: $isStop) {
                Text("Stop Loop and let text finish")
            }.padding(.horizontal)
            
            TextField("Type...", text: $text).padding(.horizontal).padding(.vertical,12).background(Color.gray.cornerRadius(10)).padding(.horizontal).foregroundColor(.white)
            
            
         
        }.onAppear {
            text = ""
            animating = true
            typeWriter()
        }.onDisappear {
            animating = false
            text = ""

        }
    }
    
    
    
    func typeWriter(at position: Int = 0) {
        if animating {
            if position == 0 {
                text = ""
            }
            if position < finalText.count {
                DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
                
                    if finalText[position] == " "{
                        text.append(" ")
                        text.append(finalText[position + 1])
                        typeWriter(at: position + 2)
                    }else{
                        text.append(finalText[position])
                        typeWriter(at: position + 1)
                    }
                 
                }
            }else if position == (finalText.count) {
                text = "Hello, World!"
                if isStop.not() {
                    DispatchQueue.main.asyncAfter(deadline: .now() + 0.4){
                       
                        typeWriter()
                    }
                }
               
                
            }
        }
    }
}


struct TypeWriterView_Previews: PreviewProvider {
    static var previews: some View {
        TypeWriterView(finalText: "Hello, World!", font: .title3, alignment: .leading).foregroundColor(.cyan).frame(width: .infinity,alignment: .leading)
    }
}

extension String {
    subscript(offset: Int) -> Character {
        self[index(startIndex, offsetBy: offset)]
    }
}
extension Bool{
     func not() -> Bool{
        return !self
    }
}