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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
/* globals browser */
"use strict";
{
const port = browser.runtime.connect();
port.onMessage.addListener(({ metaViewportChanges }) => {
const check = () => {
const metaViewport = document.querySelector("meta[name=viewport]");
if (!metaViewport) {
return;
}
const content = (metaViewport.content ?? "")
.split(",")
.map(r => r.trim())
.reduce((out, item) => {
const [key, value] = item.split("=").map(i => i.trim());
out[key] = value;
return out;
}, {});
for (const [key, _rawValue] of Object.entries(metaViewportChanges)) {
const _value =
typeof _rawValue == "string" || _rawValue === null
? { value: _rawValue }
: _rawValue;
const { only_if_equals, only_if_not_equals, value } = _value;
const givenValue = content[key] ?? null;
let shouldApplyChange = true;
if (only_if_equals !== undefined && only_if_equals !== givenValue) {
shouldApplyChange = false;
}
if (
Array.isArray(only_if_equals) &&
!only_if_equals.includes(givenValue)
) {
shouldApplyChange = false;
}
if (
only_if_not_equals !== undefined &&
only_if_not_equals === givenValue
) {
shouldApplyChange = false;
}
if (
Array.isArray(only_if_not_equals) &&
only_if_not_equals.includes(givenValue)
) {
shouldApplyChange = false;
}
if (shouldApplyChange) {
if (value == null) {
delete content[key];
} else {
content[key] = value;
}
}
}
metaViewport.setAttribute(
"content",
Object.entries(content)
.map(([k, v]) => `${k}=${v}`)
.join(",")
);
};
document.addEventListener("DOMContentLoaded", check);
if (document.readyState != "loading") {
check();
}
});
}