Add volume control to bottom panel

Changes:
- Import a reworked version of the KUKSA.val client code from the
  Flutter dashboard app, with the aggregated signal Riverpod provider
  replaced with per-signal providers for the signal the homescreen
  needs and a couple of temperature ones it might use.  Using separate
  providers is more in-line with recommended Riverpod best practices.
- Various tweaks to enable using Riverpod.
- Split the bottom panel out into its own widget, and add a stack in
  it to layer the default logo panel with the volume control slider,
  which has been added as a new widget definition to provide the hook
  to drive timer based lowering behavior like the Qt homescreen does.
- The KUKSA.val connection widget has been added to the bottom panel
  rather than overriding the top-level widget as in the dashboard and
  HVAC apps.  This seems preferable with respect to still providing
  some functionality in the event KUKSA.val is unavailable.
- Remove the old demo dashboard and HVAC pages that are now unused,
  along with the image assets they needed, to allow cleaning up
  pubspec.yaml and ease maintenance.

Bug-AGL: SPEC-4659

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: I5d9180a3461948a58321564e71134c4961ce0ef7

1 files changed, 115 insertions, 0 deletions

diff --git a/lib/config.dart b/lib/config.dart
new file mode 100644
index 0000000..6da02ed
--- /dev/null
+++ b/lib/config.dart
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: Apache-2.0
+import 'dart:io';
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:yaml/yaml.dart';
+
+import 'vehicle-signals/viss_connection_widget.dart';
+
+class GetConfig extends ConsumerStatefulWidget {
+  const GetConfig({Key? key, required this.client}) : super(key: key);
+  final HttpClient client;
+
+  @override
+  ConsumerState<GetConfig> createState() => _GetConfigState();
+}
+
+class _GetConfigState extends ConsumerState<GetConfig> {
+  @override
+  void initState() {
+    super.initState();
+    WidgetsBinding.instance.addPostFrameCallback((timeStamp) {
+      final configStateProvider = ref.read(ConfigStateprovider.notifier);
+
+      String configFilePath = '/etc/xdg/AGL/homescreen_config.yaml';
+
+      final configFile = File(configFilePath);
+      configFile.readAsString().then((content) {
+        final dynamic yamlMap = loadYaml(content);
+        configStateProvider.update(
+          read: true,
+          hostname: yamlMap['hostname'],
+          port: yamlMap['port'],
+          kuksaAuthToken: yamlMap['kuskaAuthToken'],
+        );
+      }).catchError((content) {
+        configStateProvider.update(read: true);
+      });
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final config = ref.watch(ConfigStateprovider);
+    if (!config.read) {
+      return Container(
+          child: const Text("Reading configuration file!",
+              style: TextStyle(
+                  fontSize: 20,
+                  fontWeight: FontWeight.bold,
+                  color: Colors.white)));
+    } else if (config.hostname == "" ||
+        config.port == 0 ||
+        config.kuksaAuthToken == "") {
+      return Container(
+          child: const Text("Invalid configuration file!",
+              style: TextStyle(
+                  fontSize: 20,
+                  fontWeight: FontWeight.bold,
+                  color: Colors.white)));
+    }
+    return VISServerConnectionWidget(client: widget.client);
+  }
+}
+
+class Config {
+  Config({
+    required this.read,
+    required this.hostname,
+    required this.port,
+    required this.kuksaAuthToken,
+  });
+  final bool read;
+  final String hostname;
+  final int port;
+  final String kuksaAuthToken;
+
+  Config copywith({
+    bool? read,
+    String? hostname,
+    int? port,
+    String? kuksaAuthToken,
+  }) =>
+      Config(
+        read: read ?? this.read,
+        hostname: hostname ?? this.hostname,
+        port: port ?? this.port,
+        kuksaAuthToken: kuksaAuthToken ?? this.kuksaAuthToken,
+      );
+}
+
+final ConfigStateprovider = StateNotifierProvider<ConfigStateNotifier, Config>(
+    (ref) => ConfigStateNotifier());
+
+class ConfigStateNotifier extends StateNotifier<Config> {
+  ConfigStateNotifier() : super(_initialValue);
+  static final Config _initialValue = Config(
+    read: false,
+    hostname: "",
+    port: 0,
+    kuksaAuthToken: "",
+  );
+  void update({
+    bool? read,
+    String? hostname,
+    int? port,
+    String? kuksaAuthToken,
+  }) {
+    state = state.copywith(
+      read: read,
+      hostname: hostname,
+      port: port,
+      kuksaAuthToken: kuksaAuthToken,
+    );
+  }
+}