/*
Copyright 2020 New Vector Ltd.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

// We have to trick webpack into loading our CSS for us.
require("./index.scss");

import * as qs from 'querystring';
import { Capability, WidgetApi } from "matrix-react-sdk/src/widgets/WidgetApi";
import SdkConfig from "matrix-react-sdk/src/SdkConfig";
import { loadConfig, preparePlatform } from "../initial-load";

// Dev note: we use raw JS without many dependencies to reduce bundle size.
// We do not need all of React to render a Jitsi conference.

declare var JitsiMeetExternalAPI: any;

let inConference = false;

// Jitsi params
let jitsiDomain: string;
let conferenceId: string;
let displayName: string;
let avatarUrl: string;
let userId: string;

let widgetApi: WidgetApi;

(async function () {
    try {
        // The widget's options are encoded into the fragment to avoid leaking info to the server. The widget
        // spec on the other hand requires the widgetId and parentUrl to show up in the regular query string.
        const widgetQuery = qs.parse(window.location.hash.substring(1));
        const query = Object.assign({}, qs.parse(window.location.search.substring(1)), widgetQuery);
        const qsParam = (name: string, optional = false): string => {
            if (!optional && (!query[name] || typeof (query[name]) !== 'string')) {
                throw new Error(`Expected singular ${name} in query string`);
            }
            return <string>query[name];
        };

        // Set this up as early as possible because Riot will be hitting it almost immediately.
        widgetApi = new WidgetApi(qsParam('parentUrl'), qsParam('widgetId'), [
            Capability.AlwaysOnScreen,
        ]);

        widgetApi.waitReady().then(async () => {
            // Start off by ensuring we're not stuck on screen
            await widgetApi.setAlwaysOnScreen(false);
        });

        // Bootstrap ourselves for loading the script and such
        preparePlatform();
        await loadConfig();

        // Populate the Jitsi params now
        jitsiDomain = qsParam('conferenceDomain', true) || SdkConfig.get()['jitsi']['preferredDomain'];
        conferenceId = qsParam('conferenceId');
        displayName = qsParam('displayName', true);
        avatarUrl = qsParam('avatarUrl', true); // http not mxc
        userId = qsParam('userId');

        // Get the Jitsi Meet API loaded up as fast as possible, but ensure that the widget's postMessage
        // receiver (WidgetApi) is up and running first.
        const scriptTag = document.createElement("script");
        scriptTag.src = SdkConfig.get()['jitsi']['externalApiUrl'];
        document.body.appendChild(scriptTag);

        // TODO: register widgetApi listeners for PTT controls

        document.getElementById("joinButton").onclick = () => joinConference();
    } catch (e) {
        console.error("Error setting up Jitsi widget", e);
        document.getElementById("jitsiContainer").innerText = "Failed to load Jitsi widget";
        switchVisibleContainers();
    }
})();

function switchVisibleContainers() {
    inConference = !inConference;
    document.getElementById("jitsiContainer").style.visibility = inConference ? 'unset' : 'hidden';
    document.getElementById("joinButtonContainer").style.visibility = inConference ? 'hidden' : 'unset';
}

function joinConference() { // event handler bound in HTML
    switchVisibleContainers();

    // noinspection JSIgnoredPromiseFromCall
    widgetApi.setAlwaysOnScreen(true); // ignored promise because we don't care if it works

    const meetApi = new JitsiMeetExternalAPI(jitsiDomain, {
        width: "100%",
        height: "100%",
        parentNode: document.querySelector("#jitsiContainer"),
        roomName: conferenceId,
        interfaceConfigOverwrite: {
            SHOW_JITSI_WATERMARK: false,
            SHOW_WATERMARK_FOR_GUESTS: false,
            MAIN_TOOLBAR_BUTTONS: [],
            VIDEO_LAYOUT_FIT: "height",
        },
    });
    if (displayName) meetApi.executeCommand("displayName", displayName);
    if (avatarUrl) meetApi.executeCommand("avatarUrl", avatarUrl);
    if (userId) meetApi.executeCommand("email", userId);

    meetApi.on("readyToClose", () => {
        switchVisibleContainers();

        // noinspection JSIgnoredPromiseFromCall
        widgetApi.setAlwaysOnScreen(false); // ignored promise because we don't care if it works

        document.getElementById("jitsiContainer").innerHTML = "";
    });
}