506: Enable custom timing for period reminders

Users can now specify how many days prior to their next predicted period they want to be notified

lib/notifications.js

@@ -2,9 +2,9 @@ import { Platform } from 'react-native'
 import {
   tempReminderObservable,
   periodReminderObservable,
+  advanceNoticeDaysObservable,
 } from '../local-storage'
 import * as PN from 'react-native-push-notification'
-import { requestNotifications } from 'react-native-permissions'
 import Moment from 'moment'
 import { LocalDate } from '@js-joda/core'
 
@@ -13,12 +13,14 @@ import { getBleedingDaysSortedByDate } from '../db'
 import cycleModule from './cycle'
 import nothingChanged from '../db/db-unchanged'
 
-export default function setupNotifications(navigate, setDate) {
-  Platform.OS === 'android' ? requestNotifications() : null
-  const PushNotification = Platform.OS === 'ios' ? PN : PN.default
+const DRIP_CHANNEL_ID = 'drip-channel-id'
+const TEMPERATURE_REMINDER_ID = '1'
+const PERIOD_REMINDER_ID = '2'
+const PushNotification = Platform.OS === 'ios' ? PN : PN.default
 
+export default function setupNotifications(navigate, setDate) {
   PushNotification.createChannel({
-    channelId: 'drip-channel-id', // (required)
+    channelId: DRIP_CHANNEL_ID, // (required)
     channelName: 'drip reminder', // (required)
     playSound: false, // (optional) default: true
   })
@@ -26,7 +28,10 @@ export default function setupNotifications(navigate, setDate) {
   PushNotification.configure({
     onNotification: (notification) => {
       // https://github.com/zo0r/react-native-push-notification/issues/966#issuecomment-479069106
-      if (notification.data?.id === '1' || notification.id === '1') {
+      if (
+        notification.data?.id === TEMPERATURE_REMINDER_ID ||
+        notification.id === TEMPERATURE_REMINDER_ID
+      ) {
         const todayDate = LocalDate.now().toString()
         setDate(todayDate)
         navigate('TemperatureEditView')
@@ -37,7 +42,7 @@ export default function setupNotifications(navigate, setDate) {
   })
 
   tempReminderObservable((reminder) => {
-    PushNotification.cancelLocalNotification({ id: '1' })
+    PushNotification.cancelLocalNotification({ id: TEMPERATURE_REMINDER_ID })
     if (reminder.enabled) {
       const [hours, minutes] = reminder.time.split(':')
       let target = new Moment()
@@ -50,57 +55,74 @@ export default function setupNotifications(navigate, setDate) {
       }
 
       PushNotification.localNotificationSchedule({
-        id: '1',
-        userInfo: { id: '1' },
+        id: TEMPERATURE_REMINDER_ID,
+        userInfo: { id: TEMPERATURE_REMINDER_ID },
         message: labels.tempReminder.notification,
         date: target.toDate(),
         vibrate: false,
         repeatType: 'day',
-        channelId: 'drip-channel-id',
+        channelId: DRIP_CHANNEL_ID,
         allowWhileIdle: true,
       })
     }
   }, false)
 
-  periodReminderObservable((reminder) => {
-    PushNotification.cancelLocalNotification({ id: '2' })
-    if (reminder.enabled) setupPeriodReminder()
-  }, false)
+  periodReminderObservable(() => updatePeriodNotification(), false)
+  advanceNoticeDaysObservable(() => updatePeriodNotification(), false)
 
   getBleedingDaysSortedByDate().addListener((_, changes) => {
     // the listener fires on setup, so we check if there were actually any changes
-    if (nothingChanged(changes)) return
-    PushNotification.cancelLocalNotification({ id: '2' })
-    if (periodReminderObservable.value.enabled) setupPeriodReminder()
+    if (nothingChanged(changes)) {
+      return
+    }
+
+    updatePeriodNotification()
   })
 }
 
-function setupPeriodReminder() {
-  const PushNotification = Platform.OS === 'ios' ? PN : PN.default
+const updatePeriodNotification = () => {
+  // Cancel any existing period reminder
+  PushNotification.cancelLocalNotification({ id: PERIOD_REMINDER_ID })
+
+  // Set up a new period reminder if enabled
+  if (periodReminderObservable.value.enabled) {
+    schedulePeriodNotification()
+  }
+}
+
+function schedulePeriodNotification() {
   const bleedingPrediction = cycleModule().getPredictedMenses()
+
   if (bleedingPrediction.length > 0) {
     const predictedBleedingStart = Moment(
       bleedingPrediction[0][0],
       'YYYY-MM-DD'
     )
-    // 3 days before and at 6 am
+
+    const advanceNoticeDays = parseInt(advanceNoticeDaysObservable.value, 10)
+
+    // ${advanceNoticeDays} days before and at 6 am
     const reminderDate = predictedBleedingStart
-      .subtract(3, 'days')
+      .subtract(advanceNoticeDays, 'days')
       .hours(6)
       .minutes(0)
       .seconds(0)
 
     if (reminderDate.isAfter()) {
-      // period is likely to start in 3 to 3 + (length of prediction - 1) days
-      const daysToEndOfPrediction = bleedingPrediction[0].length + 2
+      // period is likely to start in advanceNoticeDays to advanceNoticeDays + (length of prediction - 1) days
+      const daysToEndOfPrediction =
+        advanceNoticeDays + bleedingPrediction[0].length - 1
 
       PushNotification.localNotificationSchedule({
-        id: '2',
-        userInfo: { id: '2' },
-        message: labels.periodReminder.notification(daysToEndOfPrediction),
+        id: PERIOD_REMINDER_ID,
+        userInfo: { id: PERIOD_REMINDER_ID },
+        message: labels.periodReminder.notification(
+          advanceNoticeDays,
+          daysToEndOfPrediction
+        ),
         date: reminderDate.toDate(),
         vibrate: false,
-        channelId: 'drip-channel-id',
+        channelId: DRIP_CHANNEL_ID,
         allowWhileIdle: true,
       })
     }