overte/scripts/system/spectatorCamera.js

"use strict";
/*jslint vars:true, plusplus:true, forin:true*/
/*global Tablet, Script,  */
/* eslint indent: ["error", 4, { "outerIIFEBody": 0 }] */
//
// spectatorCamera.js
//
// Created by Zach Fox on 2017-06-05
// Copyright 2017 High Fidelity, Inc
//
// Distributed under the Apache License, Version 2.0
// See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//

(function () { // BEGIN LOCAL_SCOPE

    //
    // FUNCTION VAR DECLARATIONS
    //
    var sendToQml, onTabletScreenChanged, fromQml, onTabletButtonClicked, wireEventBridge, startup, shutdown;

    //
    // Function Name: startup()
    //
    // Relevant Variables:
    // button: The tablet button.
    // buttonName: The name of the button.
    // tablet: The tablet instance to be modified.
    // 
    // Arguments:
    // None
    // 
    // Description:
    // startup() will be called when the script is loaded.
    //
    var button;
    var buttonName = "SPECTATOR";
    var tablet = null;
    function startup() {
        tablet = Tablet.getTablet("com.highfidelity.interface.tablet.system");
        button = tablet.addButton({
            text: buttonName
        });
        button.clicked.connect(onTabletButtonClicked);
        tablet.screenChanged.connect(onTabletScreenChanged);
    }

    //
    // Function Name: wireEventBridge()
    //
    // Relevant Variables:
    // hasEventBridge: true/false depending on whether we've already connected the event bridge
    // 
    // Arguments:
    // on: Enable or disable the event bridge
    // 
    // Description:
    // Used to connect/disconnect the script's response to the tablet's "fromQml" signal.
    //
    var hasEventBridge = false;
    function wireEventBridge(on) {
        if (on) {
            if (!hasEventBridge) {
                tablet.fromQml.connect(fromQml);
                hasEventBridge = true;
            }
        } else {
            if (hasEventBridge) {
                tablet.fromQml.disconnect(fromQml);
                hasEventBridge = false;
            }
        }
    }

    //
    // Function Name: onTabletButtonClicked()
    //
    // Relevant Variables:
    // onSpectatorCameraScreen: true/false depending on whether we're looking at the spectator camera app
    // shouldActivateButton: true/false depending on whether we should show the button as white or gray the
    //     next time we edit the button's properties
    // 
    // Arguments:
    // None
    // 
    // Description:
    // Fired when the Spectator Camera app button is pressed.
    //
    var onSpectatorCameraScreen = false;
    var shouldActivateButton = false;
    function onTabletButtonClicked() {
        if (onSpectatorCameraScreen) {
            // for toolbar-mode: go back to home screen, this will close the window.
            tablet.gotoHomeScreen();
        } else {
            shouldActivateButton = true;
            tablet.loadQMLSource("../SpectatorCamera.qml");
            onSpectatorCameraScreen = true;
        }
    }

    //
    // Function Name: onTabletScreenChanged()
    //
    // Relevant Variables:
    // None
    // 
    // Arguments:
    // type: "Home", "Web", "Menu", "QML", "Closed"
    // url: Only valid for Web and QML.
    // 
    // Description:
    // Called when the TabletScriptingInterface::screenChanged() signal is emitted.
    //
    function onTabletScreenChanged(type, url) {
        wireEventBridge(shouldActivateButton);
        // for toolbar mode: change button to active when window is first openend, false otherwise.
        button.editProperties({ isActive: shouldActivateButton });
        shouldActivateButton = false;
        onSpectatorCameraScreen = false;
    }

    //
    // Function Name: sendToQml()
    //
    // Relevant Variables:
    // None
    // 
    // Arguments:
    // message: The message to send to the SpectatorCamera QML.
    //     Messages are in format "{method, params}", like json-rpc. See also fromQml().
    // 
    // Description:
    // Use this function to send a message to the QML (i.e. to change appearances).
    //
    function sendToQml(message) {
        tablet.sendToQml(message);
    }

    //
    // Function Name: fromQml()
    //
    // Relevant Variables:
    // None
    // 
    // Arguments:
    // message: The message sent from the SpectatorCamera QML.
    //     Messages are in format "{method, params}", like json-rpc. See also sendToQml().
    // 
    // Description:
    // Called when a message is received from SpectatorCamera.qml.
    //
    function fromQml(message) {
        switch (message.method) {
            case 'XXX':
                break;
            default:
                print('Unrecognized message from SpectatorCamera.qml:', JSON.stringify(message));
        }
    }

    //
    // Function Name: shutdown()
    //
    // Relevant Variables:
    // None
    // 
    // Arguments:
    // None
    // 
    // Description:
    // shutdown() will be called when the script ends (i.e. is stopped).
    //
    function shutdown() {
        tablet.removeButton(button);
        button.clicked.disconnect(onTabletButtonClicked);
        tablet.screenChanged.disconnect(onTabletScreenChanged);
    }

    //
    // These functions will be called when the script is loaded.
    //
    startup();
    Script.scriptEnding.connect(shutdown);

}()); // END LOCAL_SCOPE