AtomicGameEngine/Script/AtomicWebViewEditor/interop.ts

// This is the interop file, exposing functions that can be called by the host game engine
import editor from "./editor/editor";
import * as editorConfig from "./editor/editorConfig";

/**
 * Port to attach Chrome Dev Tools to
 * @type {Number}
 */
const DEBUG_PORT = 3335;

/**
 * Display "Attach dev tools now" alert on startup if this is set to true
 * @type {Boolean}
 */
const DEBUG_ALERT = false;

/**
 * Promise version of atomic query
 * @param  {string} message the query to use to pass to atomicQuery.  If there is no payload, this will be passed directly, otherwise it will be passed in a data object
 * @param  {any} payload optional data to send
 * @return {Promise}
 */
function atomicQueryPromise(message: any): Promise<{}> {
    return new Promise(function(resolve, reject) {
        let queryMessage = message;

        // if message is coming in as an object then let's stringify it
        if (typeof (message) != "string") {
            queryMessage = JSON.stringify(message);
        }

        window.atomicQuery({
            request: queryMessage,
            persistent: false,
            onSuccess: resolve,
            onFailure: (error_code, error_message) => reject({ error_code: error_code, error_message: error_message })
        });
    });
}

export default class HostInteropType {
    static EDITOR_SAVE_CODE = "editorSaveCode";
    static EDITOR_SAVE_FILE = "editorSaveFile";
    static EDITOR_LOAD_COMPLETE = "editorLoadComplete";
    static EDITOR_CHANGE = "editorChange";

    private static _inst: HostInteropType = null;
    static getInstance(): HostInteropType {
        if (HostInteropType._inst == null) {
            HostInteropType._inst = new HostInteropType();
        }
        return HostInteropType._inst;
    }

    constructor() {
        // Set up the window object so the host can call into it
        window.HOST_loadCode = this.loadCode.bind(this);
        window.HOST_saveCode = this.saveCode.bind(this);
    }

    /**
     * Called from the host to notify the client what file to load
     * @param  {string} codeUrl
     */
    loadCode(codeUrl: string) {
        console.log("Load Code called for :" + codeUrl);
        const fileExt = codeUrl.split(".").pop();
        const filename = codeUrl.replace("atomic://", "");

        // go ahead and set the theme prior to pulling the file across
        editorConfig.configure(fileExt, filename);

        // get the code
        this.getResource(codeUrl).then((src: string) => {
            editorConfig.loadCodeIntoEditor(src, filename, fileExt);
        }).catch((e: Editor.ClientExtensions.AtomicErrorMessage) => {
            console.log("Error loading code: " + e.error_message);
        });
    }

    /**
     * Save the contents of the editor
     * @return {Promise}
     */
    saveCode(): Promise<{}> {
        return atomicQueryPromise({
            message: HostInteropType.EDITOR_SAVE_CODE,
            payload: editor.session.getValue()
        });
    }

    /**
     * Save the contents of a file as filename
     * @param  {string} filename
     * @param  {string} fileContents
     * @return {Promise}
     */
    saveFile(filename: string, fileContents: string): Promise<{}> {
        return atomicQueryPromise({
            message: HostInteropType.EDITOR_SAVE_FILE,
            filename: filename,
            payload: fileContents
        });
    }

    /**
     * Call this function when the client is fully loaded up.  This will notify the host that
     * it can start loading code
     */
    editorLoaded() {
        if (DEBUG_ALERT) {
            alert(`Attach chrome dev tools to this instance by navigating to http://localhost:${DEBUG_PORT}`);
        }
        atomicQueryPromise(HostInteropType.EDITOR_LOAD_COMPLETE);
    }

    /**
     * Queries the host for a particular resource and returns it in a promise
     * @param  {string} codeUrl
     * @return {Promise}
     */
    getResource(codeUrl: string): Promise<{}> {
        return new Promise(function(resolve, reject) {
            const xmlHttp = new XMLHttpRequest();
            xmlHttp.onreadystatechange = () => {
                if (xmlHttp.readyState == 4 && xmlHttp.status == 200) {
                    resolve(xmlHttp.responseText);
                }
            };
            xmlHttp.open("GET", codeUrl, true); // true for asynchronous
            xmlHttp.send(null);
        });
    }

    /**
     * Returns a file resource from the resources directory
     * @param  {string} filename name and path of file under the project directory or a fully qualified file name
     * @return {Promise}
     */
    getFileResource(filename: string): Promise<{}> {
        return this.getResource(`atomic://${filename}`);
    }

    /**
     * Notify the host that the contents of the editor has changed
     */
    notifyEditorChange() {
        atomicQueryPromise(HostInteropType.EDITOR_CHANGE).catch((e: Editor.ClientExtensions.AtomicErrorMessage) => {
            console.log("Error on change: " + e.error_message);
        });
    }
}

HostInteropType.getInstance().editorLoaded();