/** \file
 * \brief Wrappers for High Resolution Time (Level 2) standard
 *
 * \see https://w3c.github.io/hr-time/
 *
 *  \author Copyright (C) 2025  Libor Polcak
 *
 *  \license SPDX-License-Identifier: GPL-3.0-or-later
 */
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <https://www.gnu.org/licenses/>.
//


/** \file
 * \ingroup wrappers
 *
 * This wrapper aims on prevention of microarchitectural attacks, clock-skew attacks, and other time
 * related attacks. The goal is to limit the precision of the time returned by the Temporal API.
 *
 * \see https://www.fit.vut.cz/study/thesis/22308/?year=0&sup=Pol%C4%8D%C3%A1k, especially Sect.
 * 7.2.
 *
 * \see Tom Van Goethem, Wouter Joosen, Nick Nikiforakis. The Clock is Still Ticking:
Timing Attacks in the Modern Web. CCS'15. DOI: http://dx.doi.org/10.1145/2810103.2813632.
https://lirias.kuleuven.be/retrieve/389086
 *
 * \see Schwarz, M., Lipp, M. a Gruss, D. JavaScript Zero: Real JavaScript and Zero
 *      Side-Channel Attacks. NDSS'18.
 *
 * \see Schwarz M., Maurice C., Gruss D., Mangard S. (2017) Fantastic Timers and Where to Find Them: High-Resolution Microarchitectural Attacks in JavaScript. In: Kiayias A. (eds) Financial Cryptography and Data Security. FC 2017. Lecture Notes in Computer Science, vol 10322. Springer, Cham. https://doi.org/10.1007/978-3-319-70972-7_13 
 *
 * The wrappers support the following behaviour:
 *
 * * Round timestamp: Limit the precision by removing (a part of) the decimal part of the timestamp.
 * * Randomize after rounding: Create a fake decimal part to confuse attackers and to create
 *   timestamps that look similar to expected timestamps.
 */



/*
 * Create private namespace
 */
(function() {
	var wrappers = [
		{
			parent_object: "Temporal.Now",
			parent_object_property: "instant",
			wrapped_objects: [
				{
					original_name: "Temporal.Now.instant",
					wrapped_name: "originalTemporalNowInstant",
				},
			],
			helping_code: rounding_function + noise_function +
				`
				var precision = args[0];
				var doNoise = args[1];
				var func = rounding_function;
				if (doNoise) {
					func = noise_function;
				}
				`,
			wrapping_function_args: "",
			wrapping_function_body: `
				var original = originalTemporalNowInstant();
				var originalEpochMilliseconds = original.epochMilliseconds;
				var changedValue = func(originalEpochMilliseconds, precision);
				var fakeInstant = new Temporal.Instant(BigInt(changedValue) * 1000000n); // Note that we cannot return this value as it may contain different zone and other metadata to the original
				var durationUntil = original.until(fakeInstant);
				var result = original.add(durationUntil);
				return result;
				`,
		},
	]
	add_wrappers(wrappers);
})()