feat: deep links (Android only)

android/app/src/main/AndroidManifest.xml

@@ -53,6 +53,29 @@
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
+
+            <meta-data android:name="flutter_deeplinking_enabled" android:value="false" />
+            <intent-filter android:autoVerify="true">
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data
+                  android:host="lichess.org" android:scheme="https"
+                  android:pathPrefix="/training" />
+                <data
+                  android:host="lichess.org" android:scheme="https"
+                  android:pathPrefix="/study" />
+                <!-- Either game or challenge -->
+                <data
+                  android:host="lichess.org" android:scheme="https"
+                  android:pathPattern="/........" />
+                <data
+                  android:host="lichess.org" android:scheme="https"
+                  android:pathPattern="/......../black" />
+                <data
+                  android:host="lichess.org" android:scheme="https"
+                  android:pathPattern="/......../white" />
+            </intent-filter>
         </activity>
         <!-- Don't delete the meta-data below.
              This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->

android/app/src/main/kotlin/org/lichess/mobileV2/MainActivity.kt

@@ -2,7 +2,9 @@ package org.lichess.mobileV2
 
 import android.app.ActivityManager
 import android.content.Context
+import android.content.Intent
 import android.graphics.Rect
+import android.os.Bundle
 import androidx.core.view.ViewCompat
 import io.flutter.embedding.android.FlutterActivity
 import io.flutter.embedding.engine.FlutterEngine
@@ -11,6 +13,7 @@ import io.flutter.plugin.common.MethodChannel
 class MainActivity: FlutterActivity() {
   private val GESTURES_CHANNEL = "mobile.lichess.org/gestures_exclusion"
   private val SYSTEM_CHANNEL = "mobile.lichess.org/system"
+  private val APP_LINK_CHANNEL = "mobile.lichess.org/app_links"
 
   override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
     super.configureFlutterEngine(flutterEngine)
@@ -48,6 +51,28 @@ class MainActivity: FlutterActivity() {
           }
       }
     }
+
+    MethodChannel(flutterEngine.dartExecutor.binaryMessenger, APP_LINK_CHANNEL).setMethodCallHandler {
+      call, result ->
+      when (call.method) {
+          "getAppLink" -> {
+            result.success(intent.data?.toString())
+          }
+          else -> {
+            result.notImplemented()
+          }
+      }
+    }
+  }
+
+  override fun onCreate(savedInstanceState: Bundle?) {
+    super.onCreate(savedInstanceState)
+  }
+
+  override fun onNewIntent(intent: Intent) {
+    super.onNewIntent(intent)
+    MethodChannel(flutterEngine!!.dartExecutor.binaryMessenger, APP_LINK_CHANNEL)
+      .invokeMethod("newAppLink", intent.data?.toString())
   }
 
   private fun decodeExclusionRects(inputRects: List<Map<String, Int>>): List<Rect> =

build.yaml

@@ -16,4 +16,5 @@ targets:
           - lib/src/model/**/*.dart
           - lib/src/network/*.dart
           - lib/src/db/*.dart
+          - lib/src/utils/app_links.dart
           - lib/src/**/*_providers.dart

lib/src/navigation.dart

@@ -3,7 +3,9 @@ import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:lichess_mobile/l10n/l10n.dart';
 import 'package:lichess_mobile/src/network/connectivity.dart';
+import 'package:lichess_mobile/src/utils/app_links.dart';
 import 'package:lichess_mobile/src/utils/l10n_context.dart';
+import 'package:lichess_mobile/src/utils/navigation.dart';
 import 'package:lichess_mobile/src/view/home/home_tab_screen.dart';
 import 'package:lichess_mobile/src/view/puzzle/puzzle_tab_screen.dart';
 import 'package:lichess_mobile/src/view/settings/settings_tab_screen.dart';
@@ -127,6 +129,20 @@ class BottomNavScaffold extends ConsumerWidget {
   Widget build(BuildContext context, WidgetRef ref) {
     final currentTab = ref.watch(currentBottomTabProvider);
 
+    ref.listen(appLinksProvider, (_, appLinkUri) {
+      switch (appLinkUri) {
+        case AsyncData(:final Uri value):
+          {
+            final builder = resolveAppLinkUri(value);
+            if (builder != null) {
+              WidgetsBinding.instance.addPostFrameCallback((_) {
+                pushPlatformRoute(context, rootNavigator: true, builder: builder);
+              });
+            }
+          }
+      }
+    });
+
     switch (Theme.of(context).platform) {
       case TargetPlatform.android:
         return Scaffold(

lib/src/utils/app_links.dart

@@ -0,0 +1,76 @@
+import 'dart:async';
+
+import 'package:dartchess/dartchess.dart';
+import 'package:fast_immutable_collections/fast_immutable_collections.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter/widgets.dart';
+import 'package:lichess_mobile/src/model/common/id.dart';
+import 'package:lichess_mobile/src/model/puzzle/puzzle_angle.dart';
+import 'package:lichess_mobile/src/view/game/archived_game_screen.dart';
+import 'package:lichess_mobile/src/view/puzzle/puzzle_screen.dart';
+import 'package:lichess_mobile/src/view/study/study_screen.dart';
+import 'package:logging/logging.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+part 'app_links.g.dart';
+
+final _logger = Logger('App Links');
+
+WidgetBuilder? resolveAppLinkUri(Uri appLinkUri) {
+  if (appLinkUri.pathSegments.length < 2 || appLinkUri.pathSegments[1].isEmpty) {
+    return null;
+  }
+
+  final id = appLinkUri.pathSegments[1];
+
+  switch (appLinkUri.pathSegments[0]) {
+    case 'study':
+      return (context) => StudyScreen(id: StudyId(id));
+    case 'training':
+      return (context) => PuzzleScreen(angle: PuzzleAngle.fromKey('mix'), puzzleId: PuzzleId(id));
+    case _:
+      {
+        final gameId = GameId(appLinkUri.pathSegments[0]);
+        final orientation = appLinkUri.pathSegments.getOrNull(2);
+        if (gameId.isValid) {
+          return (context) => ArchivedGameScreen(
+            gameId: gameId,
+            orientation: orientation == 'black' ? Side.black : Side.white,
+          );
+        } else {
+          // TODO if it's not a game, it's a challenge.
+          // So we should show a accept/decline screen here.
+          return null;
+        }
+      }
+  }
+}
+
+/// Receives incoming app links from the operating system (iOS or Android).
+///
+/// There are two ways a new app link can be received:
+/// 1) The app is not running, the user presses a supported link which then opens the app.
+/// 2) Like 1), but the app is already running in the background.
+///
+/// Use [resolveAppLinkUri] to get the a builder for the screen that should be displayed
+/// for the given app link URI.
+@Riverpod(keepAlive: true)
+class AppLinks extends _$AppLinks {
+  static const _channel = MethodChannel('mobile.lichess.org/app_links');
+
+  @override
+  Future<Uri?> build() async {
+    final initialLink = await _channel.invokeMethod<String?>('getAppLink');
+    _logger.info('Initial app link: $initialLink');
+
+    _channel.setMethodCallHandler((call) async {
+      if (call.method == 'newAppLink') {
+        final uri = Uri.parse(call.arguments as String);
+        _logger.info('Received new app link: $uri');
+        state = AsyncValue.data(uri);
+      }
+    });
+
+    return initialLink != null ? Uri.parse(initialLink) : null;
+  }
+}