import {BrowserWindow, app, dialog} from "electron";
import * as path from "path";

export let is_debug: boolean;
export let allow_dev_tools: boolean;

import {Arguments, processArguments} from "../../shared/process-arguments";
import * as updater from "./../app-updater";
import * as loader from "./../ui-loader";
import * as url from "url";
import {loadWindowBounds, startTrackWindowBounds} from "../../shared/window";
import {referenceApp, dereferenceApp} from "../AppInstance";

// Keep a global reference of the window object, if you don't, the window will
// be closed automatically when the JavaScript object is garbage collected.
export let mainWindow: BrowserWindow = null;

function spawnMainWindow(rendererEntryPoint: string) {
    app.on('certificate-error', (event, webContents, url, error, certificate, callback) => {
        console.log("Allowing untrusted certificate for %o", url);
        event.preventDefault();
        callback(true);
    });

    // Create the browser window.
    console.log("Spawning main window");

    referenceApp(); /* main browser window references the app */
    mainWindow = new BrowserWindow({
        width: 800,
        height: 600,

        minHeight: 600,
        minWidth: 600,

        show: false,
        webPreferences: {
            webSecurity: false,
            nodeIntegrationInWorker: true,
            nodeIntegration: true,
            preload: path.join(__dirname, "preload.js")
        },
        icon: path.join(__dirname, "..", "..", "resources", "logo.ico"),
    });

    mainWindow.webContents.on('devtools-closed', () => {
        console.log("Dev tools destroyed!");
    });

    mainWindow.on('closed', () => {
        app.releaseSingleInstanceLock();
        require("../url-preview").close();
        mainWindow = null;

        dereferenceApp();
    });

    mainWindow.loadURL(url.pathToFileURL(loader.ui.preloading_page(rendererEntryPoint)).toString()).catch(error => {
        console.error("Failed to load UI entry point: %o", error);
        handleUILoadingError("UI entry point failed to load");
    });

    mainWindow.once('ready-to-show', () => {
        mainWindow.show();
        loadWindowBounds('main-window', mainWindow).then(() => {
            startTrackWindowBounds('main-window', mainWindow);

            mainWindow.focus();
            loader.ui.cleanup();
            if(allow_dev_tools && !mainWindow.webContents.isDevToolsOpened())
                mainWindow.webContents.openDevTools();
        });
    });

    mainWindow.webContents.on('new-window', (event, url_str, frameName, disposition, options, additionalFeatures) => {
        if(frameName.startsWith("__modal_external__")) {
            return;
        }

        event.preventDefault();
        try {
            let url: URL;
            try {
                url = new URL(url_str);
            } catch(error) {
                throw "failed to parse URL";
            }

            {
                let protocol = url.protocol.endsWith(":") ? url.protocol.substring(0, url.protocol.length - 1) : url.protocol;
                if(protocol !== "https" && protocol !== "http") {
                    throw "invalid protocol (" + protocol + "). HTTP(S) are only supported!";
                }
            }

            console.log("Got new window " + frameName);
            const url_preview = require("./url-preview");
            url_preview.open_preview(url_str);
        } catch(error) {
            console.error("Failed to open preview window for URL %s: %o", url_str, error);
            dialog.showErrorBox("Failed to open preview", "Failed to open preview URL: " + url_str + "\nError: " + error);
        }
    });

    mainWindow.webContents.on('crashed', () => {
        console.error("UI thread crashed! Closing app!");
        if(!processArguments.has_flag(Arguments.DEBUG)) {
            mainWindow.close();
        }
    });
}

function handleUILoadingError(message: string) {
    referenceApp();

    console.log("Caught loading error: %s", message);
    if(mainWindow) {
        mainWindow.close();
        mainWindow = undefined;
    }

    dialog.showMessageBox({
        type: "error",
        buttons: ["exit"],
        title: "A critical error happened while loading TeaClient!",
        message: (message || "no error").toString()
    }).then(dereferenceApp);
    loader.ui.cancel();
}

export function execute() {
    console.log("Main app executed!");

    is_debug = processArguments.has_flag(...Arguments.DEBUG);
    allow_dev_tools = processArguments.has_flag(...Arguments.DEV_TOOLS);
    if(is_debug) {
        console.log("Enabled debug!");
        console.log("Arguments: %o", processArguments);
    }

    console.log("Setting up render backend");
    require("../render-backend");

    console.log("Spawn loading screen");
    loader.ui.execute_loader().then(async (entry_point: string) => {
        /* test if the updater may have an update found */
        let awaiting_update_set = false;
        while(updater.update_question_open) {
            if(!awaiting_update_set) {
                awaiting_update_set = true;
                loader.ui.show_await_update();
                console.log("Awaiting update stuff to be finished");
            }
            await new Promise(resolve => setTimeout(resolve, 100));
        }

        if(updater.update_restart_pending)
            return undefined;

        return entry_point;
    }).then((entry_point: string) => {
        referenceApp(); /* because we've no windows when we close the loader UI */
        loader.ui.cleanup(); /* close the window */

        if(entry_point) //has not been canceled
            spawnMainWindow(entry_point);
        else {
            handleUILoadingError("Missing UI entry point");
        }
        dereferenceApp();
    }).catch(handleUILoadingError);
}