/**
 * Contains the WebView class, which represents a standard browser widget.
 */
import { View, Property, EventData } from "../core/view";

/**
 * Represents the observable property backing the Url property of each WebView instance.
 */
export const urlProperty: Property<WebView, string>;

/**
 * Represents navigation type
 */
export type NavigationType = "linkClicked" | "formSubmitted" | "backForward" | "reload" | "formResubmitted" | "other" | undefined;

/**
 * Represents a standard WebView widget.
 */
export class WebView extends View {
    /**
     * String value used when hooking to loadStarted event.
     */
    public static loadStartedEvent: string;

    /**
     * String value used when hooking to loadFinished event.
     */
    public static loadFinishedEvent: string;

    /**
     * Gets the native [android widget](http://developer.android.com/reference/android/webkit/WebView.html) that represents the user interface for this component. Valid only when running on Android OS.
     */
    android: any /* android.webkit.WebView */;

    /**
     * Gets the native [UIWebView](https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIWebView_Class/) that represents the user interface for this component. Valid only when running on iOS.
     */
    ios: any /* UIWebView */;

    /**
     * Gets or sets the url, local file path or HTML string.
     */
    src: string;

    /**
     * Gets a value indicating whether the WebView can navigate back.
     */
    canGoBack: boolean;

    /**
     * Gets a value indicating whether the WebView can navigate forward.
     */
    canGoForward: boolean;

    /**
     * Stops loading the current content (if any).
     */
    stopLoading(): void;

    /**
     * Navigates back.
     */
    goBack();

    /**
     * Navigates forward.
     */
    goForward();

    /**
     * Reload the current url.
     */
    reload();

    /**
     * A basic method signature to hook an event listener (shortcut alias to the addEventListener method).
     * @param eventNames - String corresponding to events (e.g. "propertyChange"). Optionally could be used more events separated by `,` (e.g. "propertyChange", "change"). 
     * @param callback - Callback function which will be executed when event is raised.
     * @param thisArg - An optional parameter which will be used as `this` context for callback execution.
     */
    on(eventNames: string, callback: (data: EventData) => void, thisArg?: any);

    /**
     * Raised when a loadFinished event occurs.
     */
    on(event: "loadFinished", callback: (args: LoadEventData) => void, thisArg?: any);

    /**
     * Raised when a loadStarted event occurs.
     */
    on(event: "loadStarted", callback: (args: LoadEventData) => void, thisArg?: any);
}

/**
 * Event data containing information for the loading events of a WebView.
 */
export interface LoadEventData extends EventData {
    /**
     * Gets the url of the web-view.
     */
    url: string;
    /**
     * Gets the navigation type of the web-view.
     */
    navigationType: NavigationType;
    /**
     * Gets the error (if any). 
     */
    error: string;
}