/* 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
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

import { TelemetryControllerBase } from "resource://gre/modules/TelemetryControllerBase.sys.mjs";

const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
  UpdateUtils: "resource://gre/modules/UpdateUtils.sys.mjs",
});

const MILLISECONDS_PER_DAY = 24 * 60 * 60 * 1000;

const IS_CONTENT_PROCESS = (function () {
  // We cannot use Services.appinfo here because in telemetry xpcshell tests,
  // appinfo is initially unavailable, and becomes available only later on.
  // eslint-disable-next-line mozilla/use-services
  let runtime = Cc["@mozilla.org/xre/app-info;1"].getService(Ci.nsIXULRuntime);
  return runtime.processType == Ci.nsIXULRuntime.PROCESS_TYPE_CONTENT;
})();

export var TelemetryUtils = {
  /**
   * When telemetry is disabled, identifying information (such as client ID)
   * should be removed. A topic event is emitted with a subject that matches
   * this constant. When this happens, other systems that store identifying
   * information about the client should delete that data. Please ask the
   * Firefox Telemetry Team before relying on this topic.
   *
   * Here is an example of listening for that event:
   *
   *  const { TelemetryUtils } = ChromeUtils.import("resource://gre/modules/TelemetryUtils.jsm");
   *
   *  class YourClass {
   *    constructor() {
   *      Services.obs.addObserver(this, TelemetryUtils.TELEMETRY_UPLOAD_DISABLED_TOPIC);
   *    }
   *
   *    observe(subject, topic, data) {
   *      if (topic == TelemetryUtils.TELEMETRY_UPLOAD_DISABLED_TOPIC) {
   *        // Telemetry was disabled
   *        // subject and data are both unused
   *      }
   *    }
   *  }
   */
  TELEMETRY_UPLOAD_DISABLED_TOPIC: "telemetry.upload.disabled",

  Preferences: Object.freeze({
    ...TelemetryControllerBase.Preferences,

    // General Preferences
    ArchiveEnabled: "toolkit.telemetry.archive.enabled",
    CachedClientId: "toolkit.telemetry.cachedClientID",
    DisableFuzzingDelay: "toolkit.telemetry.testing.disableFuzzingDelay",
    FirstRun: "toolkit.telemetry.reportingpolicy.firstRun",
    FirstShutdownPingEnabled: "toolkit.telemetry.firstShutdownPing.enabled",
    HealthPingEnabled: "toolkit.telemetry.healthping.enabled",
    IPCBatchTimeout: "toolkit.telemetry.ipcBatchTimeout",
    OverrideOfficialCheck: "toolkit.telemetry.send.overrideOfficialCheck",
    OverrideUpdateChannel: "toolkit.telemetry.overrideUpdateChannel",
    Server: "toolkit.telemetry.server",
    ShutdownPingSender: "toolkit.telemetry.shutdownPingSender.enabled",
    ShutdownPingSenderFirstSession:
      "toolkit.telemetry.shutdownPingSender.enabledFirstSession",
    TelemetryEnabled: "toolkit.telemetry.enabled",
    UntrustedModulesPingFrequency:
      "toolkit.telemetry.untrustedModulesPing.frequency",
    UpdatePing: "toolkit.telemetry.updatePing.enabled",
    NewProfilePingEnabled: "toolkit.telemetry.newProfilePing.enabled",
    NewProfilePingDelay: "toolkit.telemetry.newProfilePing.delay",
    PreviousBuildID: "toolkit.telemetry.previousBuildID",

    // Event Ping Preferences
    EventPingMinimumFrequency: "toolkit.telemetry.eventping.minimumFrequency",
    EventPingMaximumFrequency: "toolkit.telemetry.eventping.maximumFrequency",

    // Data reporting Preferences
    AcceptedPolicyDate: "datareporting.policy.dataSubmissionPolicyNotifiedTime",
    AcceptedPolicyVersion:
      "datareporting.policy.dataSubmissionPolicyAcceptedVersion",
    BypassNotification:
      "datareporting.policy.dataSubmissionPolicyBypassNotification",
    CurrentPolicyVersion: "datareporting.policy.currentPolicyVersion",
    DataSubmissionEnabled: "datareporting.policy.dataSubmissionEnabled",
    FhrUploadEnabled: "datareporting.healthreport.uploadEnabled",
    MinimumPolicyVersion: "datareporting.policy.minimumPolicyVersion",
    FirstRunURL: "datareporting.policy.firstRunURL",
  }),

  /**
   * A fixed valid client ID used when Telemetry upload is disabled.
   */
  get knownClientID() {
    return "c0ffeec0-ffee-c0ff-eec0-ffeec0ffeec0";
  },

  /**
   * True if this is a content process.
   */
  get isContentProcess() {
    return IS_CONTENT_PROCESS;
  },

  /**
   * Returns the state of the Telemetry enabled preference, making sure
   * it correctly evaluates to a boolean type.
   */
  get isTelemetryEnabled() {
    return TelemetryControllerBase.isTelemetryEnabled;
  },

  /**
   * Turn a millisecond timestamp into a day timestamp.
   *
   * @param aMsec A number of milliseconds since Unix epoch.
   * @return The number of whole days since Unix epoch.
   */
  millisecondsToDays(aMsec) {
    return Math.floor(aMsec / MILLISECONDS_PER_DAY);
  },

  /**
   * Takes a date and returns it truncated to a date with daily precision.
   */
  truncateToDays(date) {
    return new Date(
      date.getFullYear(),
      date.getMonth(),
      date.getDate(),
      0,
      0,
      0,
      0
    );
  },

  /**
   * Takes a date and returns it truncated to a date with hourly precision.
   */
  truncateToHours(date) {
    return new Date(
      date.getFullYear(),
      date.getMonth(),
      date.getDate(),
      date.getHours(),
      0,
      0,
      0
    );
  },

  /**
   * Check if the difference between the times is within the provided tolerance.
   * @param {Number} t1 A time in milliseconds.
   * @param {Number} t2 A time in milliseconds.
   * @param {Number} tolerance The tolerance, in milliseconds.
   * @return {Boolean} True if the absolute time difference is within the tolerance, false
   *                   otherwise.
   */
  areTimesClose(t1, t2, tolerance) {
    return Math.abs(t1 - t2) <= tolerance;
  },

  /**
   * Get the next midnight for a date.
   * @param {Object} date The date object to check.
   * @return {Object} The Date object representing the next midnight.
   */
  getNextMidnight(date) {
    let nextMidnight = new Date(this.truncateToDays(date));
    nextMidnight.setDate(nextMidnight.getDate() + 1);
    return nextMidnight;
  },

  /**
   * Get the midnight which is closer to the provided date.
   * @param {Object} date The date object to check.
   * @param {Number} tolerance The tolerance within we find the closest midnight.
   * @return {Object} The Date object representing the closes midnight, or null if midnight
   *                  is not within the midnight tolerance.
   */
  getNearestMidnight(date, tolerance) {
    let lastMidnight = this.truncateToDays(date);
    if (this.areTimesClose(date.getTime(), lastMidnight.getTime(), tolerance)) {
      return lastMidnight;
    }

    const nextMidnightDate = this.getNextMidnight(date);
    if (
      this.areTimesClose(date.getTime(), nextMidnightDate.getTime(), tolerance)
    ) {
      return nextMidnightDate;
    }
    return null;
  },

  generateUUID() {
    let str = Services.uuid.generateUUID().toString();
    // strip {}
    return str.substring(1, str.length - 1);
  },

  /**
   * Find how many months passed between two dates.
   * @param {Object} aStartDate The starting date.
   * @param {Object} aEndDate The ending date.
   * @return {Integer} The number of months between the two dates.
   */
  getElapsedTimeInMonths(aStartDate, aEndDate) {
    return (
      aEndDate.getMonth() -
      aStartDate.getMonth() +
      12 * (aEndDate.getFullYear() - aStartDate.getFullYear())
    );
  },

  /**
   * Date.toISOString() gives us UTC times, this gives us local times in
   * the ISO date format. See http://www.w3.org/TR/NOTE-datetime
   * @param {Object} date The input date.
   * @return {String} The local time ISO string.
   */
  toLocalTimeISOString(date) {
    function padNumber(number, length) {
      return number.toString().padStart(length, "0");
    }

    let sign = n => (n >= 0 ? "+" : "-");
    // getTimezoneOffset counter-intuitively returns -60 for UTC+1.
    let tzOffset = -date.getTimezoneOffset();

    // YYYY-MM-DDThh:mm:ss.sTZD (eg 1997-07-16T19:20:30.45+01:00)
    return (
      padNumber(date.getFullYear(), 4) +
      "-" +
      padNumber(date.getMonth() + 1, 2) +
      "-" +
      padNumber(date.getDate(), 2) +
      "T" +
      padNumber(date.getHours(), 2) +
      ":" +
      padNumber(date.getMinutes(), 2) +
      ":" +
      padNumber(date.getSeconds(), 2) +
      "." +
      date.getMilliseconds() +
      sign(tzOffset) +
      padNumber(Math.floor(Math.abs(tzOffset / 60)), 2) +
      ":" +
      padNumber(Math.abs(tzOffset % 60), 2)
    );
  },

  /**
   * @returns {number} The monotonic time since the process start
   * or (non-monotonic) Date value if this fails back.
   */
  monotonicNow() {
    return Services.telemetry.msSinceProcessStart();
  },

  /**
   * @returns {string} The name of the update channel to report
   * in telemetry.
   * By default, this is the same as the name of the channel that
   * the browser uses to download its updates. However in certain
   * situations, a single update channel provides multiple (distinct)
   * build types, that need to be distinguishable on Telemetry.
   */
  getUpdateChannel() {
    let overrideChannel = Services.prefs.getCharPref(
      this.Preferences.OverrideUpdateChannel,
      undefined
    );
    if (overrideChannel) {
      return overrideChannel;
    }

    return lazy.UpdateUtils.getUpdateChannel(false);
  },
};