Implement sleep timer functionality (#84)

lib/screens/channel/stores/video_store.dart

@@ -1,4 +1,6 @@
 import 'dart:async';
+import 'dart:io';
+
 import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:frosty/api/twitch_api.dart';
@@ -19,6 +21,17 @@ abstract class _VideoStoreBase with Store {
 
   late Timer _overlayTimer;
 
+  Timer? sleepTimer;
+
+  @observable
+  var sleepHours = 0;
+
+  @observable
+  var sleepMinutes = 0;
+
+  @observable
+  var timeRemaining = const Duration();
+
   @readonly
   var _paused = true;
 
@@ -149,4 +162,42 @@ abstract class _VideoStoreBase with Store {
       debugPrint(e.toString());
     }
   }
+
+  /// Updates the sleep timer with [sleepHours] and [sleepMinutes].
+  void updateSleepTimer() {
+    // If hours and minutes are 0, do nothing.
+    if (sleepHours == 0 && sleepMinutes == 0) return;
+
+    // If there is an ongoing timer, cancel it since it'll be replaced.
+    if (sleepTimer != null) cancelSleepTimer();
+
+    // Update the new time remaining
+    timeRemaining = Duration(hours: sleepHours, minutes: sleepMinutes);
+
+    // Reset the hours and minutes in the dropdown buttons.
+    sleepHours = 0;
+    sleepMinutes = 0;
+
+    // Set a periodic timer that will update the time remaining every second.
+    sleepTimer = Timer.periodic(
+      const Duration(seconds: 1),
+      (timer) {
+        // If the timer is up, cancel the timer and exit the app.
+        if (timeRemaining.inSeconds == 0) {
+          timer.cancel();
+          Platform.isIOS ? exit(0) : SystemNavigator.pop();
+          return;
+        }
+
+        // Decrement the time remaining.
+        timeRemaining = Duration(seconds: timeRemaining.inSeconds - 1);
+      },
+    );
+  }
+
+  /// Cancels the sleep timer and resets the time remaining.
+  void cancelSleepTimer() {
+    sleepTimer?.cancel();
+    timeRemaining = const Duration();
+  }
 }

lib/screens/channel/stores/video_store.g.dart

@@ -17,6 +17,51 @@ mixin _$VideoStore on _VideoStoreBase, Store {
               name: '_VideoStoreBase.videoUrl'))
           .value;
 
+  final _$sleepHoursAtom = Atom(name: '_VideoStoreBase.sleepHours');
+
+  @override
+  int get sleepHours {
+    _$sleepHoursAtom.reportRead();
+    return super.sleepHours;
+  }
+
+  @override
+  set sleepHours(int value) {
+    _$sleepHoursAtom.reportWrite(value, super.sleepHours, () {
+      super.sleepHours = value;
+    });
+  }
+
+  final _$sleepMinutesAtom = Atom(name: '_VideoStoreBase.sleepMinutes');
+
+  @override
+  int get sleepMinutes {
+    _$sleepMinutesAtom.reportRead();
+    return super.sleepMinutes;
+  }
+
+  @override
+  set sleepMinutes(int value) {
+    _$sleepMinutesAtom.reportWrite(value, super.sleepMinutes, () {
+      super.sleepMinutes = value;
+    });
+  }
+
+  final _$timeRemainingAtom = Atom(name: '_VideoStoreBase.timeRemaining');
+
+  @override
+  Duration get timeRemaining {
+    _$timeRemainingAtom.reportRead();
+    return super.timeRemaining;
+  }
+
+  @override
+  set timeRemaining(Duration value) {
+    _$timeRemainingAtom.reportWrite(value, super.timeRemaining, () {
+      super.timeRemaining = value;
+    });
+  }
+
   final _$_pausedAtom = Atom(name: '_VideoStoreBase._paused');
 
   bool get paused {
@@ -124,6 +169,9 @@ mixin _$VideoStore on _VideoStoreBase, Store {
   @override
   String toString() {
     return '''
+sleepHours: ${sleepHours},
+sleepMinutes: ${sleepMinutes},
+timeRemaining: ${timeRemaining},
 videoUrl: ${videoUrl}
     ''';
   }

lib/screens/channel/video/video_overlay.dart

@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'dart:io';
 
 import 'package:flutter/material.dart';
@@ -12,6 +13,69 @@ class VideoOverlay extends StatelessWidget {
 
   const VideoOverlay({Key? key, required this.videoStore}) : super(key: key);
 
+  Future<void> _showSleepTimerDialog(BuildContext context) {
+    return showDialog(
+      context: context,
+      builder: (context) => AlertDialog(
+        title: const Text('Sleep Timer'),
+        content: Observer(
+          builder: (context) => Column(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              Row(
+                mainAxisAlignment: MainAxisAlignment.center,
+                children: [
+                  DropdownButton(
+                    value: videoStore.sleepHours,
+                    items: List.generate(24, (index) => index).map((e) => DropdownMenuItem(value: e, child: Text(e.toString()))).toList(),
+                    onChanged: (int? hours) => videoStore.sleepHours = hours!,
+                    menuMaxHeight: 200,
+                  ),
+                  const SizedBox(width: 10.0),
+                  const Text('Hours'),
+                ],
+              ),
+              Row(
+                mainAxisAlignment: MainAxisAlignment.center,
+                children: [
+                  DropdownButton(
+                    value: videoStore.sleepMinutes,
+                    items: List.generate(60, (index) => index).map((e) => DropdownMenuItem(value: e, child: Text(e.toString()))).toList(),
+                    onChanged: (int? minutes) => videoStore.sleepMinutes = minutes!,
+                    menuMaxHeight: 200,
+                  ),
+                  const SizedBox(width: 10.0),
+                  const Text('Minutes'),
+                ],
+              ),
+              Row(
+                children: [
+                  Text('Timer: ${videoStore.timeRemaining.toString().split('.')[0]}'),
+                  const Spacer(),
+                  IconButton(
+                    onPressed: videoStore.cancelSleepTimer,
+                    icon: const Icon(Icons.cancel),
+                  ),
+                ],
+              ),
+            ],
+          ),
+        ),
+        actions: [
+          TextButton(
+            onPressed: Navigator.of(context).pop,
+            child: const Text('Close'),
+          ),
+          TextButton(
+            onPressed: videoStore.updateSleepTimer,
+            child: const Text('Set Timer'),
+            style: TextButton.styleFrom(primary: Colors.green),
+          ),
+        ],
+      ),
+    );
+  }
+
   @override
   Widget build(BuildContext context) {
     final orientation = MediaQuery.of(context).orientation;
@@ -70,7 +134,7 @@ class VideoOverlay extends StatelessWidget {
     final sleepTimerButton = IconButton(
       tooltip: 'Sleep Timer',
       icon: const Icon(Icons.timer),
-      onPressed: () {},
+      onPressed: () => _showSleepTimerDialog(context),
     );
 
     final streamInfo = videoStore.streamInfo;