Endpoints with enum

ApiService.swift

import Foundation

// let charactersURL = ApiService.character.url
//output: url = https://rickandmortyapi.com/api/character

// let url = ApiService.characterPage(19).url
// output: url = https://rickandmortyapi.com/api/character/?page=19

enum ApiService {
    private var baseURL: String { return "https://rickandmortyapi.com/api" }

    case character
    case characterPage(Int)
    case locations
    case episodes
    
    private var fullPath: String {
        var endpoint:String
        switch self {
        case .character:
            endpoint = "/character"
        case .characterPage(let id):
            endpoint = "/character/?page=\(id)"
        case .locations:
            endpoint = "/locations"
        case .episodes:
            endpoint = "/episodes"
        }
        return baseURL + endpoint
    }
    
    var url: URL {
        guard let url = URL(string: fullPath) else {
            preconditionFailure("The url used in \(ApiService.self) is not valid")
        }
        return url
    }
}