/* 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/. */

/**
 * Helpers for manipulating calendar alarms
 */

// NOTE: This module should not be loaded directly, it is available when
// including calUtils.jsm under the cal.alarm namespace.

const EXPORTED_SYMBOLS = ["calalarms"];

var { XPCOMUtils } = ChromeUtils.importESModule("resource://gre/modules/XPCOMUtils.sys.mjs");

const lazy = {};

ChromeUtils.defineModuleGetter(lazy, "cal", "resource:///modules/calendar/calUtils.jsm");
XPCOMUtils.defineLazyModuleGetters(lazy, {
  CalAlarm: "resource:///modules/CalAlarm.jsm",
});

var calalarms = {
  /**
   * Read default alarm settings from user preferences and apply them to the
   * event/todo passed in. The item's calendar should be set to ensure the
   * correct alarm type is set.
   *
   * @param aItem     The item to apply the default alarm values to.
   */
  setDefaultValues(aItem) {
    let type = aItem.isEvent() ? "event" : "todo";
    if (Services.prefs.getIntPref("calendar.alarms.onfor" + type + "s", 0) == 1) {
      let alarmOffset = lazy.cal.createDuration();
      let alarm = new lazy.CalAlarm();
      let units = Services.prefs.getStringPref("calendar.alarms." + type + "alarmunit", "minutes");

      // Make sure the alarm pref is valid, default to minutes otherwise
      if (!["weeks", "days", "hours", "minutes", "seconds"].includes(units)) {
        units = "minutes";
      }

      alarmOffset[units] = Services.prefs.getIntPref("calendar.alarms." + type + "alarmlen", 0);
      alarmOffset.normalize();
      alarmOffset.isNegative = true;
      if (type == "todo" && !aItem.entryDate) {
        // You can't have an alarm if the entryDate doesn't exist.
        aItem.entryDate = lazy.cal.dtz.now();
      }
      alarm.related = Ci.calIAlarm.ALARM_RELATED_START;
      alarm.offset = alarmOffset;

      // Default to a display alarm, unless the calendar doesn't support
      // it or we have no calendar yet. (Man this is hard to wrap)
      let actionValues = (aItem.calendar &&
        aItem.calendar.getProperty("capabilities.alarms.actionValues")) || ["DISPLAY"];

      alarm.action = actionValues.includes("DISPLAY") ? "DISPLAY" : actionValues[0];
      aItem.addAlarm(alarm);
    }
  },

  /**
   * Calculate the alarm date for a calIAlarm.
   *
   * @param aItem     The item used to calculate the alarm date.
   * @param aAlarm    The alarm to calculate the date for.
   * @returns The alarm date.
   */
  calculateAlarmDate(aItem, aAlarm) {
    if (aAlarm.related == Ci.calIAlarm.ALARM_RELATED_ABSOLUTE) {
      return aAlarm.alarmDate;
    }
    let returnDate;
    if (aAlarm.related == Ci.calIAlarm.ALARM_RELATED_START) {
      returnDate = aItem[lazy.cal.dtz.startDateProp(aItem)];
    } else if (aAlarm.related == Ci.calIAlarm.ALARM_RELATED_END) {
      returnDate = aItem[lazy.cal.dtz.endDateProp(aItem)];
    }

    if (returnDate && aAlarm.offset) {
      // Handle all day events.  This is kinda weird, because they don't
      // have a well defined startTime.  We just consider the start/end
      // to be midnight in the user's timezone.
      if (returnDate.isDate) {
        let timezone = lazy.cal.dtz.defaultTimezone;
        // This returns a copy, so no extra cloning needed.
        returnDate = returnDate.getInTimezone(timezone);
        returnDate.isDate = false;
      } else if (returnDate.timezone.tzid == "floating") {
        let timezone = lazy.cal.dtz.defaultTimezone;
        returnDate = returnDate.getInTimezone(timezone);
      } else {
        // Clone the date to correctly add the duration.
        returnDate = returnDate.clone();
      }

      returnDate.addDuration(aAlarm.offset);
      return returnDate;
    }

    return null;
  },

  /**
   * Removes previous children and adds reminder images to a given container,
   * making sure only one icon per alarm action is added.
   *
   * @param {Element} container - The element to add the images to.
   * @param {CalAlarm[]} reminderSet - The set of reminders to add images for.
   */
  addReminderImages(container, reminderSet) {
    while (container.lastChild) {
      container.lastChild.remove();
    }

    let document = container.ownerDocument;
    let suppressed = container.hasAttribute("suppressed");
    let actionSet = [];
    for (let reminder of reminderSet) {
      // Up to one icon per action
      if (actionSet.includes(reminder.action)) {
        continue;
      }
      actionSet.push(reminder.action);

      let src;
      let l10nId;
      switch (reminder.action) {
        case "DISPLAY":
          if (suppressed) {
            src = "chrome://messenger/skin/icons/new/bell-disabled.svg";
            l10nId = "calendar-editable-item-reminder-icon-suppressed-alarm";
          } else {
            src = "chrome://messenger/skin/icons/new/bell.svg";
            l10nId = "calendar-editable-item-reminder-icon-alarm";
          }
          break;
        case "EMAIL":
          src = "chrome://messenger/skin/icons/new/mail-sm.svg";
          l10nId = "calendar-editable-item-reminder-icon-email";
          break;
        case "AUDIO":
          src = "chrome://messenger/skin/icons/new/bell-ring.svg";
          l10nId = "calendar-editable-item-reminder-icon-audio";
          break;
        default:
          // Never create icons for actions we don't handle.
          continue;
      }

      let image = document.createElement("img");
      image.setAttribute("class", "reminder-icon");
      image.setAttribute("value", reminder.action);
      image.setAttribute("src", src);
      // Set alt.
      document.l10n.setAttributes(image, l10nId);
      container.appendChild(image);
    }
  },
};