Class that simulates a network and responds with list of countries

SlowNetwork.kt

/* 
* Product Requirement: The function SlowNetwork::getCountries returns a list of countries. Display the name of the first country on screen.
* Tapping on the country text will display a toast saying "The capital for <country name> is <country capital>"
*
* Things to note:
* + Start by creating a new project on Android Studio. Copy the entire contents of this file to your project.
* + You are not allowed to edit the contents of this file.
* + You are free to choose your path for implementing this solution.
* + You are allowed to look through any documentation and/or use a search engine for reference on syntax.
* + Please think out loud to keep the interviewers engaged in your solution.
*/

// Change the package name to the one from your project
package com.usertesting.codinginterview.network

import android.os.Looper
import java.lang.Exception

interface SlowNetwork {
    fun getCountries(): String
    fun getCapitolFor(countryCode: String): String
}
    
class SlowNetworkImpl : SlowNetwork {
    override fun getCountries(): String {
        if (Thread.currentThread().equals(Looper.getMainLooper().thread)) {
            throw Exception("Cannot call from main thread")
        }

        Thread.sleep(5000)
        return COUNTRIES
    }

    override fun getCapitolFor(countryCode: String): String {
        if (Thread.currentThread().equals(Looper.getMainLooper().thread)) {
            throw Exception("Cannot call from main thread")
        }

        Thread.sleep(4000)
        return when (countryCode) {
            "AFG" -> {
               CAPITALS.get(0)
            }
            "DEN" -> {
                CAPITALS.get(1)
            }
            "IRL" -> {
                CAPITALS.get(2)
            }
            "RUSS" -> {
                CAPITALS.get(3)
            }
            "TAI" -> {
                CAPITALS.get(4)
            }
            else -> {
                "Unknown code"
            }
        }
    }
}


val COUNTRIES = """
[
        {
            "country_name": "Afghanistan",
            "country_code": "AFG"
        },
        {
            "country_name": "Denmark",
            "country_code": "DEN"
        },
        {
            "country_name": "Ireland",
            "country_code": "IRL"
        },
        {
            "country_name": "Russian Federation",
            "country_code": "RUSS"
        },
        {
            "country_name": "Taiwan",
            "country_code": "TAI"
        }
]
""".trimIndent()

val CAPITALS = listOf("""{ "country_name": "Afghanistan", "capital": "Kabul" }""",
                      """{ "country_name": "Denmark", "capital": "Copenhagen" }""",
                      """{ "country_name": "Ireland", "capital": "Dublin" }""",
                      """{ "country_name": "Russian Federation", "capital": "Moscow" }""",
                      """{ "country_name": "Taiwan Federation", "capital": "Taipei" }""")