Files
moxxy/lib/ui/service/thumbnail.dart

116 lines
3.7 KiB
Dart

import 'dart:isolate';
import 'dart:typed_data';
import 'package:flutter_image_compress/flutter_image_compress.dart';
import 'package:flutter_isolate/flutter_isolate.dart';
import 'package:logging/logging.dart';
import 'package:moxxyv2/shared/cache.dart';
import 'package:moxxyv2/shared/semaphore.dart';
import 'package:video_thumbnail/video_thumbnail.dart';
Future<void> _generateVideoThumbnail(List<dynamic> values) async {
final port = values[0] as SendPort;
final path = values[1] as String;
try {
final data = await VideoThumbnail.thumbnailData(
video: path,
quality: 75,
);
port.send(data);
} catch (_) {
port.send(Uint8List(0));
}
}
Future<void> _generateImageThumbnail(List<dynamic> values) async {
final port = values[0] as SendPort;
final path = values[1] as String;
final data = await FlutterImageCompress.compressWithFile(
path,
quality: 75,
);
port.send(data);
}
class ThumbnailCacheService {
ThumbnailCacheService()
// TODO(Unknown): Maybe raise this limit
: _thumbnailCache = LRUCache(200),
_cacheSemaphore = Semaphore(8),
_log = Logger('ThumbnailCacheService');
final Logger _log;
// Asset path -> decoded data
final LRUCache<String, Uint8List> _thumbnailCache;
final Semaphore _cacheSemaphore;
Future<void> invalidateEntry(String path) async {
_log.fine('invalidateEntry: Waiting to aquire semaphore...');
await _cacheSemaphore.aquire();
_thumbnailCache.remove(path);
await _cacheSemaphore.release();
}
Future<Uint8List> getVideoThumbnail(String path) async {
// Turning this into a critical section allows us to prevent multiple calls to the
// isolate in case we generate thumbnails for the same path multiple times.
_log.fine('getVideoThumbnail: Waiting to acquire semaphore...');
await _cacheSemaphore.aquire();
_log.fine('getVideoThumbnail: Done');
if (_thumbnailCache.inCache(path)) {
_log.finest('Thumbnail data is in cache!');
await _cacheSemaphore.release();
_log.finest('getVideoThumbnail: Released semaphore');
return _thumbnailCache.getValue(path)!;
}
_log.finest('Thumbnail data not in cache generating...');
final port = ReceivePort();
final isolate = await FlutterIsolate.spawn(_generateVideoThumbnail, [ port.sendPort, path ]);
final data = await port.first as Uint8List;
isolate.kill(priority: Isolate.immediate);
_log.finest('Generation done.');
_thumbnailCache.cache(path, Uint8List.fromList(data));
await _cacheSemaphore.release();
_log.finest('getVideoThumbnail: Released semaphore');
return data;
}
Future<Uint8List> getImageThumbnail(String path) async {
// Turning this into a critical section allows us to prevent multiple calls to the
// isolate in case we generate thumbnails for the same path multiple times.
_log.finest('getImageThumbnail: Waiting to aquire semaphore...');
await _cacheSemaphore.aquire();
_log.finest('getImageThumbnail: Done');
if (_thumbnailCache.inCache(path)) {
_log.finest('Thumbnail data is in cache!');
await _cacheSemaphore.release();
_log.finest('getImageThumbnail: Released semaphore');
return _thumbnailCache.getValue(path)!;
}
_log.finest('Thumbnail data not in cache generating...');
final port = ReceivePort();
final isolate = await FlutterIsolate.spawn(_generateImageThumbnail, [ port.sendPort, path ]);
final data = await port.first as Uint8List;
isolate.kill(priority: Isolate.immediate);
_log.finest('Generation done.');
_thumbnailCache.cache(path, Uint8List.fromList(data));
await _cacheSemaphore.release();
_log.finest('getImageThumbnail: Released semaphore');
return data;
}
}