fix: desktop drop of HTTP content on linux

Signed-off-by: The one with the braid <the-one@with-the-braid.cf>

lib/main.dart

@@ -1,12 +1,14 @@
 import 'package:flutter/material.dart';
 
 import 'package:collection/collection.dart';
+import 'package:desktop_drop/desktop_drop.dart';
 import 'package:flutter_app_lock/flutter_app_lock.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 import 'package:matrix/matrix.dart';
 
 import 'package:fluffychat/config/app_config.dart';
 import 'package:fluffychat/utils/client_manager.dart';
+import 'package:fluffychat/utils/desktop_drop_downloader.dart';
 import 'package:fluffychat/utils/platform_infos.dart';
 import 'config/setting_keys.dart';
 import 'utils/background_push.dart';
@@ -65,6 +67,9 @@ Future<void> startGui(List<Client> clients) async {
     }
   }
 
+  DesktopDropPlugin.onUnsupportedUriHandler =
+      DesktopDropDownloader.unsupportedUriCallback;
+
   // Start rendering the Flutter app and wrap it in an Applock.
   // We do this only for mobile applications as we saw routing
   // problems on other platforms if we wrap it always.

lib/utils/desktop_drop_downloader.dart

@@ -0,0 +1,48 @@
+import 'dart:io';
+
+import 'package:flutter/foundation.dart';
+
+import 'package:http/http.dart';
+import 'package:path_provider/path_provider.dart';
+
+abstract class DesktopDropDownloader {
+  const DesktopDropDownloader._();
+
+  static Future<String?> unsupportedUriCallback(String url) async {
+    if (kIsWeb) return null;
+    final uri = Uri.tryParse(url);
+    if (uri == null) return null;
+
+    if (!['http', 'https'].contains(uri.scheme)) return null;
+
+    Response response;
+
+    try {
+      response = await get(uri);
+    } catch (_) {
+      return null;
+    }
+
+    Directory tmp;
+
+    // that's likely failing on many distros but future proof for upcoming
+    // implementations
+    try {
+      tmp = await getTemporaryDirectory();
+    } catch (_) {
+      tmp =
+          await getDownloadsDirectory() ?? await getApplicationCacheDirectory();
+    }
+
+    try {
+      await tmp.create(recursive: true);
+      final file =
+          File('${tmp.path}/desktop_drop_example/${uri.path.split('/').last}');
+      await file.create(recursive: true);
+      await file.writeAsBytes(response.bodyBytes);
+      return file.path;
+    } catch (_) {
+      return null;
+    }
+  }
+}

pubspec.lock

@@ -284,11 +284,12 @@ packages:
   desktop_drop:
     dependency: "direct main"
     description:
-      name: desktop_drop
-      sha256: "4ca4d960f4b11c032e9adfd2a0a8ac615bc3fddb4cbe73dcf840dd8077582186"
-      url: "https://pub.dev"
-    source: hosted
-    version: "0.4.1"
+      path: "packages/desktop_drop"
+      ref: "braid/unsupported-uri-scheme-callback"
+      resolved-ref: cbcea137c4f8209e2d229335278d06e16390f974
+      url: "https://github.com/TheOneWithTheBraid/flutter-plugins.git"
+    source: git
+    version: "0.4.3"
   desktop_lifecycle:
     dependency: "direct main"
     description:

pubspec.yaml

@@ -148,6 +148,11 @@ msix_config:
   install_certificate: false
 
 dependency_overrides:
+  desktop_drop:
+    git:
+      url: https://github.com/TheOneWithTheBraid/flutter-plugins.git
+      path: packages/desktop_drop
+      ref: braid/unsupported-uri-scheme-callback
   geolocator_android:
     hosted:
       name: geolocator_android