music source and client for subsonic

test fixture setup for navidrome

lib/sources/subsonic/client.dart

@@ -0,0 +1,85 @@
+import 'dart:convert';
+import 'dart:math';
+
+import 'package:crypto/crypto.dart';
+import 'package:http/http.dart';
+import 'package:xml/xml.dart';
+
+import 'xml.dart';
+
+class SubsonicClient {
+  SubsonicClient({
+    required this.http,
+    required this.address,
+    required this.username,
+    required this.password,
+    this.useTokenAuth = true,
+  });
+
+  final BaseClient http;
+  final Uri address;
+  final String username;
+  final String password;
+  final bool useTokenAuth;
+
+  Uri uri(
+    String method, [
+    Map<String, String?>? extraParams,
+  ]) {
+    final pathSegments = [...address.pathSegments, 'rest', '$method.view'];
+
+    final queryParameters = {
+      ..._params(),
+      ...(extraParams ?? {}),
+    }..removeWhere((_, value) => value == null);
+
+    return Uri(
+      scheme: address.scheme,
+      host: address.host,
+      port: address.hasPort ? address.port : null,
+      pathSegments: pathSegments,
+      queryParameters: queryParameters,
+    );
+  }
+
+  Future<SubsonicResponse> get(
+    String method, [
+    Map<String, String?>? extraParams,
+  ]) async {
+    final res = await http.get(uri(method, extraParams));
+
+    final subsonicResponse = SubsonicResponse(
+      XmlDocument.parse(utf8.decode(res.bodyBytes)),
+    );
+
+    if (subsonicResponse.status == Status.failed) {
+      final error = SubsonicException(subsonicResponse.xml);
+      throw error;
+    }
+
+    return subsonicResponse;
+  }
+
+  String _salt() {
+    final r = Random();
+    return String.fromCharCodes(
+      List.generate(4, (index) => r.nextInt(92) + 33),
+    );
+  }
+
+  Map<String, String> _params() {
+    final Map<String, String> p = {};
+    p['v'] = '1.13.0';
+    p['c'] = 'subtracks';
+    p['u'] = username;
+
+    if (useTokenAuth) {
+      p['s'] = _salt();
+      p['t'] = md5.convert(utf8.encode(password + p['s']!)).toString();
+    } else {
+      p['p'] = password;
+    }
+
+    return p;
+  }
+}