const { dialog } = require("electron");
const { autoUpdater } = require("electron-updater");
const { Logger } = require("lib/logger.js");
const { _ } = require("lib/locale.js");

let autoUpdateLogger_ = new Logger();
let checkInBackground_ = false;
let isCheckingForUpdate_ = false;
let parentWindow_ = null;

// Note: Electron Builder's autoUpdater is incredibly buggy so currently it's only used
// to detect if a new version is present. If it is, the download link is simply opened
// in a new browser window.
autoUpdater.autoDownload = false;

function htmlToText_(html) {
	let output = html.replace(/\n/g, "");
	output = output.replace(/<li>/g, "- ");
	output = output.replace(/<p>/g, "");
	output = output.replace(/<\/p>/g, "\n");
	output = output.replace(/<\/li>/g, "\n");
	output = output.replace(/<ul>/g, "");
	output = output.replace(/<\/ul>/g, "");
	output = output.replace(/<.*?>/g, "");
	output = output.replace(/<\/.*?>/g, "");
	return output;
}

function showErrorMessageBox(message) {
	return dialog.showMessageBox(parentWindow_, {
		type: "error",
		message: message,
	});
}

function onCheckStarted() {
	autoUpdateLogger_.info("checkForUpdates: Starting...");
	isCheckingForUpdate_ = true;
}

function onCheckEnded() {
	autoUpdateLogger_.info("checkForUpdates: Done.");
	isCheckingForUpdate_ = false;
}

autoUpdater.on("error", error => {
	autoUpdateLogger_.error(error);
	if (checkInBackground_) return onCheckEnded();

	let msg = error == null ? "unknown" : (error.stack || error).toString();
	// Error messages can be very long even without stack trace so shorten
	// then so that the dialog box doesn't take the whole screen.
	msg = msg.substr(0, 512).replace(/\\n/g, "\n");
	showErrorMessageBox(msg);

	onCheckEnded();
});

function findDownloadFilename_(info) {
	// { version: '1.0.64',
	//   files:
	//    [ { url: 'Joplin-1.0.64-mac.zip',
	//        sha512: 'OlemXqhq/fSifx7EutvMzfoCI/1kGNl10i8nkvACEDfVXwP8hankDBXEC0+GxSArsZuxOh3U1+C+4j72SfIUew==' },
	//      { url: 'Joplin-1.0.64.dmg',
	//        sha512: 'jAewQQoJ3nCaOj8hWDgf0sc3LBbAWQtiKqfTflK8Hc3Dh7fAy9jRHfFAZKFUZ9ll95Bun0DVsLq8wLSUrdsMXw==',
	//        size: 77104485 } ],
	//   path: 'Joplin-1.0.64-mac.zip',
	//   sha512: 'OlemXqhq/fSifx7EutvMzfoCI/1kGNl10i8nkvACEDfVXwP8hankDBXEC0+GxSArsZuxOh3U1+C+4j72SfIUew==',
	//   releaseDate: '2018-02-16T00:13:01.634Z',
	//   releaseName: 'v1.0.64',
	//   releaseNotes: '<p>Still more fixes and im...' }

	if (!info) return null;

	if (!info.files) {
		// info.path seems to contain a default, though not a good one,
		// so the loop below if preferable to find the right file.
		return info.path;
	}

	for (let i = 0; i < info.files.length; i++) {
		const f = info.files[i].url; // Annoyingly this is called "url" but it's obviously not a url, so hopefully it won't change later on and become one.
		if (f.indexOf(".exe") >= 0) return f;
		if (f.indexOf(".dmg") >= 0) return f;
	}

	return info.path;
}

autoUpdater.on("update-available", info => {
	const filename = findDownloadFilename_(info);

	if (!info.version || !filename) {
		if (checkInBackground_) return onCheckEnded();
		showErrorMessageBox("Could not get version info: " + JSON.stringify(info));
		return onCheckEnded();
	}

	const downloadUrl = "https://github.com/laurent22/joplin/releases/download/v" + info.version + "/" + filename;

	let releaseNotes = info.releaseNotes + "";
	if (releaseNotes) releaseNotes = "\n\n" + _("Release notes:\n\n%s", htmlToText_(releaseNotes));

	const buttonIndex = dialog.showMessageBox(parentWindow_, {
		type: "info",
		message: _("An update is available, do you want to download it now?" + releaseNotes),
		buttons: [_("Yes"), _("No")],
	});

	onCheckEnded();

	if (buttonIndex === 0) require("electron").shell.openExternal(downloadUrl);
});

autoUpdater.on("update-not-available", () => {
	if (checkInBackground_) return onCheckEnded();
	dialog.showMessageBox({ message: _("Current version is up-to-date.") });
	onCheckEnded();
});

function checkForUpdates(inBackground, window, logFilePath) {
	if (isCheckingForUpdate_) {
		autoUpdateLogger_.info("checkForUpdates: Skipping check because it is already running");
		return;
	}

	parentWindow_ = window;

	onCheckStarted();

	if (logFilePath && !autoUpdateLogger_.targets().length) {
		autoUpdateLogger_ = new Logger();
		autoUpdateLogger_.addTarget("file", { path: logFilePath });
		autoUpdateLogger_.setLevel(Logger.LEVEL_DEBUG);
		autoUpdateLogger_.info("checkForUpdates: Initializing...");
		autoUpdater.logger = autoUpdateLogger_;
	}

	checkInBackground_ = inBackground;

	try {
		autoUpdater.checkForUpdates();
	} catch (error) {
		autoUpdateLogger_.error(error);
		if (!checkInBackground_) showErrorMessageBox(error.message);
		onCheckEnded();
	}
}

module.exports.checkForUpdates = checkForUpdates;