MemorizeApp.swift ------------------------------------------------------------------------------

import SwiftUI

@main
struct MemorizeApp: App {
    
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

ContentView.swift ------------------------------------------------------------------------------

import SwiftUI


struct ContentView: View {
    var emojis = ["🚙", "🚗", "⛱", "🎡", "🪝", "🗿", "🛖", "⏱", "☎️", "🎰","🚜","🛴", "✈️"]
    @State var emojiCount = 4
    
    var body: some View {
        VStack {
            ScrollView {
                LazyVGrid(columns: [GridItem(.adaptive(minimum: 65))]){
                    ForEach(emojis[0..<emojiCount], id: \.self) { emoji in
                        CardView(content: emoji).aspectRatio(2/3, contentMode: .fit)
                    }
                }
            }
            .foregroundColor(.red)
            Spacer()
            HStack {
                remove
                Spacer()
                add
            }
            .font(.largeTitle)
            .padding(.horizontal)
        }
        .padding(.horizontal)
        
    }
    var remove: some View {
        Button(action:{
            if emojiCount > 1{
                emojiCount -= 1
            }
        }, label: {
            Image(systemName: "minus.circle")
        })
    }
    var add: some View {
        Button(action:{
            if emojiCount < emojis.count {
                emojiCount += 1
            }
        }, label: {
            Image(systemName: "plus.circle")
        })
    }
}

struct CardView: View {
    var content: String
    @State var isFaceUp: Bool = true
    
    var body: some View {
        ZStack {
            let shape = RoundedRectangle(cornerRadius: 20)
            if isFaceUp {
                shape.fill().foregroundColor(.white)
                shape.strokeBorder(lineWidth: 3)
                Text(content).font(.largeTitle)
                
            } else {
                shape.fill()
            }
        }
        .onTapGesture {
            isFaceUp = !isFaceUp
        }
    }
}


struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
            .preferredColorScheme(/*@START_MENU_TOKEN@*/.dark/*@END_MENU_TOKEN@*/)
        ContentView()
            .preferredColorScheme(.light)
    }
}

MemoryGame.swift ------------------------------------------------------------------------------

import Foundation

struct MemoryGame<CardContent> {
    var cards: Array<Card>
    
    func choose(_ card: Card) {
        
    }
    
    init(numberOfPairOfCards: Int, createCardContent: (Int) -> CardContent ) {
        cards = Array<Card>()
        for pairIndex in 0..<numberOfPairOfCards {
            let content: CardContent = createCardContent(pairIndex)
            cards.append(Card(content: content))
            cards.append(Card(content: content))
        }
    }
    struct Card {
        var isFaceUp: Bool = false
        var isMatched: Bool = false
        var content: CardContent
    }
}

EmojiMemoryGame.swift ------------------------------------------------------------------------------

import SwiftUI


class EmojiMemoryGame {
    static var emojis = ["🚙", "🚗", "⛱", "🎡", "🪝", "🗿", "🛖", "⏱", "☎️", "🎰","🚜","🛴", "✈️"]
    
    static func makeMemoryGame() -> MemoryGame<String> {
        MemoryGame<String>(numberOfPairOfCards: 4) { pairIndex in EmojiMemoryGame.emojis[pairIndex] }
    }
    var model: MemoryGame<String> = makeMemoryGame()
    
    var cards: Array<MemoryGame<String>.Card> {
        return model.cards
    }
}