import WKJavaScriptController

// Create protocol.
// '@objc' keyword is required. because method call is based on ObjC.
@objc protocol JavaScriptInterface {
    func onSubmit(_ dictonary: [String: AnyObject])
    func onSubmit(_ email: String, firstName: String, lastName: String, address1: String, address2: String, zipCode: JSInt, phoneNumber: String)
    func onCancel()
    var isSubmitted: JSBool { get }
    @objc optional func getErrorMessages(codes: [JSInt]) -> [String]
}

// Implement protocol. 
extension ViewController: JavaScriptInterface {
    func onSubmit(_ dictonary: [String: AnyObject]) {
        NSLog("onSubmit \(dictonary)")
    }
    
    func onSubmit(_ email: String, firstName: String, lastName: String, address1: String, address2: String, zipCode: JSInt, phoneNumber: String) {
        NSLog("onSubmit \(email), \(firstName), \(lastName), \(address1), \(address2), \(zipCode.value), \(phoneNumber)")
    }
    
    func onCancel() {
        NSLog("onCancel")
    }
    
    var isSubmitted: JSBool {
        return JSBool(true)
    }
    
    func getErrorMessages(codes: [JSInt]) -> [String] {
        return codes.map { "message\($0)" }
    }
}

class ViewController: UIViewController {
    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        
        // Create javaScriptController.
        let javaScriptController = WKJavaScriptController(name: "native", target: self, bridgeProtocol: JavaScriptInterface.self)
        
        // [Optional] Add your javascript.
        let jsString = ...
        let userScript = WKUserScript(source: jsString, injectionTime: .AtDocumentEnd, forMainFrameOnly: true)
        javaScriptController.addUserScript(userScript)
        
        let webView = WKWebView(...)
        ...
        
        // Assign javaScriptController.
        webView.javaScriptController = javaScriptController
        
        // Call prepareForJavaScriptController before initializing WKWebView or loading page.
        webView.prepareForJavaScriptController()
        webView.loadRequest(...)
    }
    
    ...
}