Create a service to load and cache remote assets

lib/services/remote_assets_service.dart

@@ -0,0 +1,57 @@
+import "dart:io";
+
+import "package:logging/logging.dart";
+import "package:path_provider/path_provider.dart";
+import "package:photos/core/network/network.dart";
+
+class RemoteAssetsService {
+  static final _logger = Logger("RemoteAssetsService");
+
+  RemoteAssetsService._privateConstructor();
+
+  static final RemoteAssetsService instance =
+      RemoteAssetsService._privateConstructor();
+
+  Future<File> getAsset(String remotePath) async {
+    final path = await _getLocalPath(remotePath);
+    final file = File(path);
+    if (await file.exists()) {
+      _logger.info("Returning cached file for $remotePath");
+      return file;
+    } else {
+      final tempFile = File(path + ".temp");
+      await _downloadFile(remotePath, tempFile.path);
+      await tempFile.rename(path);
+      return File(path);
+    }
+  }
+
+  Future<String> _getLocalPath(String remotePath) async {
+    return (await getTemporaryDirectory()).path +
+        "/assets/" +
+        _urlToFileName(remotePath);
+  }
+
+  String _urlToFileName(String url) {
+    // Remove the protocol part (http:// or https://)
+    String fileName = url
+        .replaceAll(RegExp(r'https?://'), '')
+        // Replace all non-alphanumeric characters except for underscores and periods with an underscore
+        .replaceAll(RegExp(r'[^\w\.]'), '_');
+    // Optionally, you might want to trim the resulting string to a certain length
+
+    // Replace periods with underscores for better readability, if desired
+    fileName = fileName.replaceAll('.', '_');
+
+    return fileName;
+  }
+
+  Future<void> _downloadFile(String url, String savePath) async {
+    _logger.info("Downloading " + url);
+    final existingFile = File(savePath);
+    if (await existingFile.exists()) {
+      await existingFile.delete();
+    }
+    await NetworkClient.instance.getDio().download(url, savePath);
+  }
+}