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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
/**
* Notifies observers that quitting has been requested.
*
* @returns {boolean} - True if an observer prevented quitting, false otherwise.
*/
function canQuitApplication() {
try {
const cancelQuit = Cc["@mozilla.org/supports-PRBool;1"].createInstance(
Ci.nsISupportsPRBool
);
Services.obs.notifyObservers(cancelQuit, "quit-application-requested");
// Something aborted the quit process.
if (cancelQuit.data) {
return false;
}
} catch (ex) {}
return true;
}
/**
* Quit the application if no `quit-application-requested` observer prevents it.
*/
function goQuitApplication() {
if (!canQuitApplication()) {
return false;
}
Services.startup.quit(Ci.nsIAppStartup.eAttemptQuit);
return true;
}
/**
* Gets the first registered controller that returns true for both
* `supportsCommand` and `isCommandEnabled`, or null if no controllers
* return true for both.
*
* @param {string} command - The command name to pass to controllers.
* @returns {nsIController|null}
*/
function getEnabledControllerForCommand(command) {
// The first controller for which `supportsCommand` returns true.
const controllerA =
top.document.commandDispatcher.getControllerForCommand(command);
if (controllerA?.isCommandEnabled(command)) {
return controllerA;
}
// Didn't find a controller, or `isCommandEnabled` returned false?
// Try the other controllers. Note this isn't exactly the same set
// of controllers as `commandDispatcher` has.
for (let i = 0; i < top.controllers.getControllerCount(); i++) {
const controllerB = top.controllers.getControllerAt(i);
if (
controllerB !== controllerA &&
controllerB.supportsCommand(command) &&
controllerB.isCommandEnabled(command)
) {
return controllerB;
}
}
return null;
}
/**
* Updates the enabled state of the element with the ID `command`. The command
* is considered enabled if at least one controller returns true for both
* `supportsCommand` and `isCommandEnabled`.
*
* @param {string} command - The command name to pass to controllers.
*/
function goUpdateCommand(command) {
try {
goSetCommandEnabled(command, !!getEnabledControllerForCommand(command));
} catch (e) {
console.error(`An error occurred updating the ${command} command: ${e}`);
}
}
/**
* Calls `doCommand` on the first controller that returns true for both
* `supportsCommand` and `isCommandEnabled`.
*
* @param {string} command - The command name to pass to controllers.
* @param {any[]} args - Any number of arguments to pass to the chosen
* controller. Note that passing arguments is not part of the `nsIController`
* interface and only possible for JS controllers.
*/
function goDoCommand(command, ...args) {
try {
let controller = getEnabledControllerForCommand(command);
if (controller) {
controller = controller.wrappedJSObject ?? controller;
controller.doCommand(command, ...args);
}
} catch (e) {
console.error(`An error occurred executing the ${command} command: ${e}`);
}
}
/**
* Updates the enabled state of the element with the ID `id`.
*
* @param {string} id
* @param {boolean} enabled
* @fires {CustomEvent} commandstate - Fired on the window when there is no
* command element matching the id. Detail is an object with the command
* property containing the id, and the enabled property containing the passed
* value.
*/
function goSetCommandEnabled(id, enabled) {
const node = document.getElementById(id);
if (node) {
if (enabled) {
node.removeAttribute("disabled");
} else {
node.setAttribute("disabled", "true");
}
} else {
const commandStateEvent = new CustomEvent("commandstate", {
detail: { command: id, enabled },
});
window.dispatchEvent(commandStateEvent);
}
}