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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
const MINUTE_IN_MS = 60000;
const HOUR_IN_MS = 3600000;
const DAY_IN_MS = 86400000;
/**
* Keeps calendar UI/components in sync by ticking regularly. Fires a "minute"
* event every minute on the minute, an "hour" event on the hour, and a "day"
* event at midnight. Each event also fires if longer than the time period in
* question has elapsed since the last event, e.g. because the computer has
* been asleep.
*
* It automatically corrects clock skew: if a minute event is more than one
* second late, the time to the next event is recalculated and should fire a
* few milliseconds late at worst.
*
* @implements {nsIObserver}
* @implements {EventEmitter}
*/
export var CalMetronome = {
QueryInterface: ChromeUtils.generateQI(["nsIObserver"]),
/**
* The time when the minute event last fired, in milliseconds since the epoch.
*
* @type {integer}
*/
_lastFireTime: 0,
/**
* The last minute for which the minute event fired.
*
* @type {integer} (0-59)
*/
_lastMinute: -1,
/**
* The last hour for which the hour event fired.
*
* @type {integer} (0-23)
*/
_lastHour: -1,
/**
* The last day of the week for which the day event fired.
*
* @type {integer} (0-7)
*/
_lastDay: -1,
/**
* The timer running everything.
*
* @type {nsITimer}
*/
_timer: Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer),
init() {
const now = new Date();
this._lastFireTime = now.valueOf();
this._lastHour = now.getHours();
this._lastDay = now.getDay();
EventEmitter.decorate(this);
Services.obs.addObserver(this, "wake_notification");
Services.obs.addObserver(this, "quit-application");
this._startNext();
},
observe(subject, topic) {
if (topic == "wake_notification") {
cal.LOGverbose("[CalMetronome] Observed wake_notification");
this.notify();
} else if (topic == "quit-application") {
this._timer.cancel();
Services.obs.removeObserver(this, "wake_notification");
Services.obs.removeObserver(this, "quit-application");
}
},
_startNext() {
this._timer.cancel();
const now = new Date();
const next = new Date(
now.getFullYear(),
now.getMonth(),
now.getDate(),
now.getHours(),
now.getMinutes() + 1,
0
);
cal.LOGverbose(`[CalMetronome] Scheduling one-off event in ${next - now}ms`);
this._timer.initWithCallback(this, next - now, Ci.nsITimer.TYPE_ONE_SHOT);
},
_startRepeating() {
cal.LOGverbose(`[CalMetronome] Starting repeating events`);
this._timer.initWithCallback(this, MINUTE_IN_MS, Ci.nsITimer.TYPE_REPEATING_SLACK);
},
notify() {
const now = new Date();
const elapsedSinceLastFire = now.valueOf() - this._lastFireTime;
this._lastFireTime = now.valueOf();
const minute = now.getMinutes();
if (minute != this._lastMinute || elapsedSinceLastFire > MINUTE_IN_MS) {
this._lastMinute = minute;
this.emit("minute", now);
}
const hour = now.getHours();
if (hour != this._lastHour || elapsedSinceLastFire > HOUR_IN_MS) {
this._lastHour = hour;
this.emit("hour", now);
}
const day = now.getDay();
if (day != this._lastDay || elapsedSinceLastFire > DAY_IN_MS) {
this._lastDay = day;
this.emit("day", now);
}
const slack = now.getSeconds();
if (slack >= 1 && slack < 59) {
this._startNext();
} else if (this._timer.type == Ci.nsITimer.TYPE_ONE_SHOT) {
this._startRepeating();
}
},
};
CalMetronome.init();