LoginModuleRouter.swift

/**
 This interface defines few simple steps:
    - store the module route, so it can be accessed many times
    - route the request sent to the module with parameters to desired functionality which is encapsulated in the module
 */
protocol ModuleRouter {
    
    var route: String { get set }
    init(route: String)
    
    func route(parameters: ModuleParameters?,
               path: String?,
               callback: ModuleCallback?)
}

// A simple way of formalising request parameters within a module
enum LoginModuleParameters: String {
    
    case username
    case password
    case paymentToken
    case bearerToken
}

class LoginModuleRouter: ModuleRouter {

    lazy var interactor = LoginInteractor()
    internal var route: String
    
    required init(route: String) {
        
        self.route = route
    }
    
    func route(parameters: ModuleParameters?,
               path: String?,
               callback: ModuleCallback?) {
        
        switch path {
            
        case "/payment-token":
            
            interactor.getPaymentToken(parameters: parameters) { (token, urlResponse, error) in
                
                if let token = token {
                    
                    let response = [LoginModuleParameters.paymentToken.rawValue: token]
                    callback?(response, nil, urlResponse, nil)
                }
                else {
                    
                    // Simplyfication of error response
                    callback?(nil, nil, nil, error)
                }
            }
        
        case "/login":
            
            interactor.login(parameters: parameters) { (token, urlResponse, error) in
                
                if let token = token {
                    
                    let response = [LoginModuleParameters.bearerToken.rawValue: token]
                    callback?(response, nil, urlResponse, nil)
                }
                else {
                    
                    // Simplyfication of error response
                    callback?(nil, nil, nil, error)
                }
            }
            
        default:
            return
        }
    }
}