medium_decodable_example.swift

import Foundation
import SwiftUI

// 1. The actual Decodable structure
struct CatFact: Codable {
    
    // 2. nested codable structure
    struct Status: Codable {
        let verified: Bool
        let sentCount: Int
    }
    
    let id: Int
    let status: Status
    let type: String
    let text: String
    let deleted: Bool
}

// 3. SwiftUI view, for the sake of simplicity and readability

struct ContentView: View {
    
    @ObservedObject private var viewModel = ViewModel()
    
    var body: some View {
        VStack {
            List {
                ForEach(viewModel.facts, id: \.id) { fact in
                    Text(fact.text)
                }
            }
        }
        .onAppear {
            viewModel.loadData()
        }
    }
}

// ViewModel which holds the data

class ViewModel: ObservableObject {
    
    @Published var facts: [CatFact] = []
    
    // 4. fetch data
    func loadData() {
        // This data can come from any place, an api service or json file
        let json = [
            [
                "id": 1,
                "status": [
                    "verified": true,
                    "sent_count": 1
                ],
                "text": "Most cats are lactose intolerant.",
                "deleted": false,
                "type": "cat"
            ],
            [
                "id": 2,
                "status": [
                    "verified": false,
                    "sent_count": 2
                ],
                "text": "Most cats are lactose intolerant",
                "deleted": true,
                "type": "dog"
            ]
        ]
        
        // 5. decoding the data
        self.facts = [CatFact].parse(from: json, strategy: .convertFromSnakeCase) ?? []
    }
}