subtitleFontFile option value can be an http url

Author: wang-bin

example/.gitignore

@@ -5,10 +5,13 @@
 *.swp
 .DS_Store
 .atom/
+.build/
 .buildlog/
 .history
 .svn/
+.swiftpm/
 migrate_working_dir/
+.cxx/
 
 # IntelliJ related
 *.iml

lib/fvp.dart

@@ -1,4 +1,4 @@
-// Copyright 2022-2024 Wang Bin. All rights reserved.
+// Copyright 2022-2025 Wang Bin. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -23,13 +23,13 @@ export 'src/controller.dart';
 ///
 /// 'lowLatency': int. default is 0. reduce network stream latency. 1: for vod. 2: for live stream, may drop frames to ensure the latest content is displayed
 ///
-/// "player": backend player properties of type Map<String, String>. See https://github.com/wang-bin/mdk-sdk/wiki/Player-APIs#void-setpropertyconst-stdstring-key-const-stdstring-value
+/// "player": backend player properties of type [Map<String, String>]. See https://github.com/wang-bin/mdk-sdk/wiki/Player-APIs#void-setpropertyconst-stdstring-key-const-stdstring-value
 ///
-/// "global": backend global options of type Map<String, Object>. See https://github.com/wang-bin/mdk-sdk/wiki/Global-Options
+/// "global": backend global options of type [Map<String, Object>]. See https://github.com/wang-bin/mdk-sdk/wiki/Global-Options
 ///
 /// "tunnel": android only, default is false. AMediacodec/MediaCodec decoder output to a SurfaceTexture surface directly without OpenGL. Maybe more efficient, but some features are not supported, e.g. HDR tone mapping, less codecs.
 ///
-/// 'subtitleFontFile': default subtitle font file as the fallback. If not set, 'assets/subfont.ttf' will be used, you can add it in pubspec.yaml if you need it.
+/// 'subtitleFontFile': default subtitle font file as the fallback, can be an http url. If not set, 'assets/subfont.ttf' will be used, you can add it in pubspec.yaml if you need it.
 /// subfont.ttf can be downloaded from https://github.com/mpv-android/mpv-android/raw/master/app/src/main/assets/subfont.ttf
 ///
 /// Example:
@@ -53,6 +53,7 @@ class VideoPlayerRegistrant {
     MdkVideoPlayerPlatform.registerVideoPlayerPlatformsWith();
   }
 }
+
 /*
 bool isRegistered() {
   return VideoPlayerPlatform.instance.runtimeType == MdkVideoPlayerPlatform;

lib/src/video_player_mdk.dart

@@ -1,4 +1,4 @@
-// Copyright 2022-2024 Wang Bin. All rights reserved.
+// Copyright 2022-2025 Wang Bin. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -8,6 +8,8 @@ import 'package:flutter/widgets.dart'; //
 import 'package:flutter/services.dart';
 import 'package:video_player_platform_interface/video_player_platform_interface.dart';
 import 'package:logging/logging.dart';
+import 'package:http/http.dart' as http;
+import 'package:path_provider/path_provider.dart';
 import 'fvp_platform_interface.dart';
 import 'extensions.dart';
 import 'media_info.dart';
@@ -147,6 +149,7 @@ class MdkVideoPlayerPlatform extends VideoPlayerPlatform {
       _tunnel = options["tunnel"];
       _playerOpts = options['player'];
       _globalOpts = options['global'];
+      // TODO: _env => putenv
       _decoders = options['video.decoders'];
       _subtitleFontFile = options['subtitleFontFile'];
     }
@@ -196,8 +199,28 @@ class MdkVideoPlayerPlatform extends VideoPlayerPlatform {
     // mdk.setGlobalOptions('plugins', 'mdk-braw');
     mdk.setGlobalOption("log", "all");
     mdk.setGlobalOption('d3d11.sync.cpu', 1);
-    mdk.setGlobalOption('subtitle.fonts.file',
-        PlatformEx.assetUri(_subtitleFontFile ?? 'assets/subfont.ttf'));
+    if (_subtitleFontFile?.startsWith('http') ?? false) {
+      final fileName = _subtitleFontFile!.split('/').last;
+      getApplicationCacheDirectory().then((dir) {
+        final fontPath = '${dir.path}/$fileName';
+        _log.fine('check font path: $fontPath');
+        if (File(fontPath).existsSync()) {
+          mdk.setGlobalOption('subtitle.fonts.file', fontPath);
+          return;
+        }
+        _log.fine('downloading font file: $_subtitleFontFile');
+        http.get(Uri.parse(_subtitleFontFile!)).then((response) {
+          if (response.statusCode == 200) {
+            _log.fine('save font file: $fontPath');
+            File(fontPath).writeAsBytes(response.bodyBytes).then((_) {
+              mdk.setGlobalOption('subtitle.fonts.file', fontPath);
+            });
+          }
+        });
+      });
+    } else {
+      mdk.setGlobalOption('subtitle.fonts.file', PlatformEx.assetUri(_subtitleFontFile ?? 'assets/subfont.ttf'));
+    }
     _globalOpts?.forEach((key, value) {
       mdk.setGlobalOption(key, value);
     });

pubspec.yaml

@@ -10,8 +10,8 @@ topics:
   - videoplayer
 
 environment:
-  sdk: '>=3.0.0 <4.0.0'
-  flutter: ">=3.0.0"
+  sdk: ^3.0.0
+  flutter: ^3.0.0
 
 dependencies:
   ffi: ^2.1.0
@@ -22,6 +22,8 @@ dependencies:
   plugin_platform_interface: ^2.0.0
   video_player: ^2.6.0
   video_player_platform_interface: ^6.2.0
+  path_provider: ^2.1.2
+  http: ^1.0.0
 
 dev_dependencies:
   flutter_test:
@@ -46,7 +48,7 @@ flutter:
   # All these are used by the tooling to maintain consistency when
   # adding or updating assets for this project.
   plugin:
-    #implements: video_player # flutter 3.27+ can only select 1 implementation
+    #implements: video_player #  endorsed. flutter 3.27+ can only select 1 implementation
     platforms:
       android:
         package: com.mediadevkit.fvp
@@ -70,10 +72,10 @@ flutter:
   #   - images/a_dot_ham.jpeg
   #
   # For details regarding assets in packages, see
-  # https://flutter.dev/assets-and-images/#from-packages
+  # https://flutter.dev/to/asset-from-package
   #
   # An image asset can refer to one or more resolution-specific "variants", see
-  # https://flutter.dev/assets-and-images/#resolution-aware
+  # https://flutter.dev/to/resolution-aware-images
 
   # To add custom fonts to your plugin package, add a fonts section here,
   # in this "flutter" section. Each entry in this list should have a
@@ -93,4 +95,4 @@ flutter:
   #         weight: 700
   #
   # For details regarding fonts in packages, see
-  # https://flutter.dev/custom-fonts/#from-packages
+  # https://flutter.dev/to/font-from-package