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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/* global MPShowMessage, MPIsEnabled, MPShouldShowHint */
"use strict";
// decode a 16-bit string in which only one byte of each
// 16-bit unit is occupied, to UTF-8. This is necessary to
// comply with `btoa` API constraints.
function fromBinary(encoded) {
const binary = atob(decodeURIComponent(encoded));
const bytes = new Uint8Array(binary.length);
for (let i = 0; i < bytes.length; i++) {
bytes[i] = binary.charCodeAt(i);
}
return String.fromCharCode(...new Uint16Array(bytes.buffer));
}
function decodeMessageFromUrl() {
const url = new URL(document.location.href);
if (url.searchParams.has("json")) {
const encodedMessage = url.searchParams.get("json");
return fromBinary(encodedMessage);
}
return null;
}
function showHint() {
document.body.classList.add("hint-box");
document.body.innerHTML = `<div class="hint">Message preview is not enabled. Enable it in about:config by setting <code>browser.newtabpage.activity-stream.asrouter.devtoolsEnabled</code> to true.</div>`;
}
const message = decodeMessageFromUrl();
if (message) {
// If message preview is enabled, show the message.
if (MPIsEnabled()) {
MPShowMessage(message);
} else if (MPShouldShowHint()) {
// If running in a local build, show a hint about how to enable preview.
if (document.body) {
showHint();
} else {
document.addEventListener("DOMContentLoaded", showHint, { once: true });
}
}
}