ente/lib/utils/file_util.dart

import 'dart:io' as io;
import 'dart:typed_data';

import 'package:path/path.dart';
import 'package:dio/dio.dart';
import 'package:flutter_cache_manager/flutter_cache_manager.dart';
import 'package:flutter_image_compress/flutter_image_compress.dart';
import 'package:photo_manager/photo_manager.dart';
import 'package:photos/core/cache/image_cache.dart';
import 'package:photos/core/cache/thumbnail_cache.dart';
import 'package:photos/core/configuration.dart';
import 'package:photos/core/constants.dart';
import 'package:photos/db/files_db.dart';
import 'package:photos/models/file.dart';
import 'package:photos/models/file_type.dart';

import 'crypto_util.dart';

Future<void> deleteFiles(List<File> files,
    {bool deleteEveryWhere = false}) async {
  await PhotoManager.editor
      .deleteWithIds(files.map((file) => file.localID).toList());
  for (File file in files) {
    deleteEveryWhere
        ? await FilesDB.instance.markForDeletion(file)
        : await FilesDB.instance.delete(file);
  }
}

void preloadFile(File file) {
  if (file.fileType == FileType.video) {
    return;
  }
  if (file.localID == null) {
    _getBytesFromServer(file);
  } else {
    if (FileLruCache.get(file) == null) {
      file.getAsset().then((asset) {
        asset.file.then((assetFile) {
          FileLruCache.put(file, assetFile);
        });
      });
    }
  }
}

void preloadLocalFileThumbnail(File file) {
  if (file.localID == null ||
      ThumbnailLruCache.get(file, THUMBNAIL_SMALL_SIZE) != null) {
    return;
  }
  file.getAsset().then((asset) {
    asset
        .thumbDataWithSize(THUMBNAIL_SMALL_SIZE, THUMBNAIL_SMALL_SIZE)
        .then((data) {
      ThumbnailLruCache.put(file, THUMBNAIL_SMALL_SIZE, data);
    });
  });
}

Future<Uint8List> getBytes(File file, {int quality = 100}) async {
  if (file.localID == null) {
    return _getBytesFromServer(file);
  } else {
    return await _getBytesFromDisk(file, quality);
  }
}

Future<Uint8List> _getBytesFromDisk(File file, int quality) async {
  final originalBytes = (await file.getAsset()).originBytes;
  if (extension(file.title) == ".HEIC" || quality != 100) {
    return originalBytes.then((bytes) {
      return FlutterImageCompress.compressWithList(bytes, quality: quality)
          .then((converted) {
        return Uint8List.fromList(converted);
      });
    });
  } else {
    return originalBytes;
  }
}

Future<Uint8List> _getBytesFromServer(File file) async {
  if (!file.isEncrypted) {
    return DefaultCacheManager()
        .getSingleFile(file.getDownloadUrl())
        .then((file) => file.readAsBytesSync());
  } else {
    return DefaultCacheManager()
        .getFileFromCache(file.getDownloadUrl())
        .then((info) {
      if (info == null) {
        return _downloadAndDecrypt(file);
      } else {
        return info.file.readAsBytesSync();
      }
    });
  }
}

Future<Uint8List> _downloadAndDecrypt(File file) async {
  final temporaryPath = Configuration.instance.getTempDirectory() +
      file.generatedID.toString() +
      ".aes";
  return Dio().download(file.getDownloadUrl(), temporaryPath).then((_) async {
    final data = await CryptoUtil.decryptFileToData(
        temporaryPath, Configuration.instance.getKey());
    io.File(temporaryPath).deleteSync();
    DefaultCacheManager().putFile(file.getDownloadUrl(), data);
    return data;
  });
}