Configurable units fixes

Notable changes:
- Add pressure unit to the units model.
- Add tire pressure unit configuration page under settings.
- Rework the VSS client, provider, and the associated handling in
  the vehicle and audio state providers to make the signal updating
  code reusable for processing the result of VAL API get commands.
- Add logic to get the initial values of the used VSS signals so
  the initial application state looks sane in demo scenarios.
- Add VSS signal support to the units provider so that changes will
  be pushed out for e.g. IC use.
- Fix pressure unit use in various widgets.
- Fix up range calculation for dashboard to correctly account for
  units and the incoming VSS value being in meters.
- Fix some unit naming inconsistencies around capitalization.

Bug-AGL: SPEC-5031, SPEC-5032

Change-Id: I33ac735dfbe35283bd30c92aa157cbdb7af1837c
Signed-off-by: Scott Murray <scott.murray@konsulko.com>

1 files changed, 13 insertions, 4 deletions

diff --git a/lib/data/models/units.dart b/lib/data/models/units.dart
index 9e71213..c299a12 100644
--- a/lib/data/models/units.dart
+++ b/lib/data/models/units.dart
@@ -4,32 +4,39 @@ enum DistanceUnit { kilometers, miles }
 
 enum TemperatureUnit { celsius, fahrenheit }
 
+enum PressureUnit { kilopascals, psi }
+
 @immutable
 class Units {
   final DistanceUnit distanceUnit;
   final TemperatureUnit temperatureUnit;
+  final PressureUnit pressureUnit;
 
   const Units(
     this.distanceUnit,
     this.temperatureUnit,
+    this.pressureUnit,
   );
   const Units.initial()
       : distanceUnit = DistanceUnit.kilometers,
-        temperatureUnit = TemperatureUnit.celsius;
+        temperatureUnit = TemperatureUnit.celsius,
+        pressureUnit = PressureUnit.kilopascals;
 
   Units copyWith({
     DistanceUnit? distanceUnit,
     TemperatureUnit? temperatureUnit,
+    PressureUnit? pressureUnit,
   }) {
     return Units(
       distanceUnit ?? this.distanceUnit,
       temperatureUnit ?? this.temperatureUnit,
+      pressureUnit ?? this.pressureUnit,
     );
   }
 
   @override
   String toString() =>
-      'Units(distanceUnit: $distanceUnit, temperatureUnit: $temperatureUnit)';
+      'Units(distanceUnit: $distanceUnit, temperatureUnit: $temperatureUnit, pressureUnit: $pressureUnit)';
 
   @override
   bool operator ==(Object other) {
@@ -37,9 +44,11 @@ class Units {
 
     return other is Units &&
         other.distanceUnit == distanceUnit &&
-        other.temperatureUnit == temperatureUnit;
+        other.temperatureUnit == temperatureUnit &&
+        other.pressureUnit == pressureUnit;
   }
 
   @override
-  int get hashCode => distanceUnit.hashCode ^ temperatureUnit.hashCode;
+  int get hashCode =>
+      distanceUnit.hashCode ^ temperatureUnit.hashCode ^ pressureUnit.hashCode;
 }