feat(display): Sprint 7 — USB serial link to AR-Concentrador via NMEA $PARP

- Add flutter_libserialport dependency (pubspec.yaml) - New ParpCodec: XOR-checksum NMEA parser + command builders for all PARP sentences - New ConcentradorService: manages two independent COM ports (RX-OUT broadcast, TX-IN commands) at 115200/8N1; auto-fires onConnectionChanged on link drop - AutopilotState: dual-mode operation (demo timer OR live serial); connectToSerial / disconnectSerial; command methods (engage/disengage/adjustSetpoint) forward to ConcentradorService when connected; falls back to demo on disconnect - New PortSettingsScreen (/settings/ports): RX+TX dropdowns populated from SerialPort.availablePorts, persisted in SharedPreferences; Connect/Disconnect buttons with error display and snackbar feedback - main.dart: auto-connect to saved ports on startup (silent fail → demo mode); registers /settings/ports route - CockpitScreen: gear icon replaced with PopupMenuButton (Puertos COM / Apariencia) AR_electronics — AR-Autopilot Project
2026-05-24 01:28:04 -04:00
parent c946d2df6d
commit abe9b764c7
7 changed files with 886 additions and 81 deletions
@@ -0,0 +1,144 @@
+// =============================================================================
+//  services/parp_codec.dart — $PARP sentence parser and builder
+// =============================================================================
+//
+//  Protocol reference: docs/concentrador_protocol.md
+//
+//  Inbound ($PARP,STATUS — broadcast by concentrador at 2 Hz):
+//    $PARP,STATUS,<mode>,<setpoint>,<heading>,<rudder>,<commander>*XX\r\n
+//    Example: $PARP,STATUS,HEADING_HOLD,125.0,125.3,2.5,01*3A
+//
+//  Outbound ($PARP commands — sent by display to concentrador):
+//    $PARP,<CMD>,<value>,<station_id>*XX\r\n
+//    Example: $PARP,ENGAGE,0.0,02*XX
+// =============================================================================
+
+import '../widgets/themed/mode_selector.dart';
+
+/// Parsed content of a $PARP,STATUS sentence.
+class ParpStatus {
+  const ParpStatus({
+    required this.mode,
+    required this.setpointDeg,
+    required this.headingDeg,
+    required this.rudderDeg,
+    required this.commander,
+  });
+
+  final AutopilotMode mode;
+  final double setpointDeg;
+  final double headingDeg;
+  final double rudderDeg;
+  final int commander; // station ID of the current commander (0 = none)
+}
+
+/// Stateless NMEA $PARP sentence codec.
+abstract final class ParpCodec {
+  // ---------------------------------------------------------------------------
+  //  Inbound parser
+  // ---------------------------------------------------------------------------
+
+  /// Parse a complete NMEA sentence string (with or without leading $).
+  ///
+  /// Returns [ParpStatus] if the sentence is a valid $PARP,STATUS with correct
+  /// checksum. Returns null for any other sentence type or if CRC fails.
+  static ParpStatus? parseStatus(String sentence) {
+    // Strip whitespace / CRLF
+    final s = sentence.trim();
+
+    // Locate checksum delimiter
+    final starIdx = s.lastIndexOf('*');
+    if (starIdx < 0) return null;
+
+    final body = s.startsWith('\$') ? s.substring(1, starIdx) : s.substring(0, starIdx);
+    final crcHex = s.substring(starIdx + 1);
+
+    // Verify checksum
+    if (!_crcOk(body, crcHex)) return null;
+
+    // Tokenise
+    final parts = body.split(',');
+    if (parts.length < 7) return null;
+    if (parts[0] != 'PARP' || parts[1] != 'STATUS') return null;
+
+    final mode = _parseMode(parts[2]);
+    final setpoint = double.tryParse(parts[3]);
+    final heading = double.tryParse(parts[4]);
+    final rudder = double.tryParse(parts[5]);
+    final commander = int.tryParse(parts[6]);
+
+    if (setpoint == null || heading == null || rudder == null || commander == null) {
+      return null;
+    }
+
+    return ParpStatus(
+      mode: mode,
+      setpointDeg: setpoint,
+      headingDeg: heading,
+      rudderDeg: rudder,
+      commander: commander,
+    );
+  }
+
+  // ---------------------------------------------------------------------------
+  //  Outbound builders
+  // ---------------------------------------------------------------------------
+
+  static String engage(int stationId, double currentHeadingDeg) =>
+      _build('ENGAGE', currentHeadingDeg, stationId);
+
+  static String disengage(int stationId) =>
+      _build('DISENGAGE', 0.0, stationId);
+
+  static String setHeading(int stationId, double headingDeg) =>
+      _build('SETHEADING', headingDeg, stationId);
+
+  static String portOne(int stationId, double currentSetpoint) =>
+      _build('PORTONE', currentSetpoint, stationId);
+
+  static String stbdOne(int stationId, double currentSetpoint) =>
+      _build('STBDONE', currentSetpoint, stationId);
+
+  static String portTen(int stationId, double currentSetpoint) =>
+      _build('PORTTEN', currentSetpoint, stationId);
+
+  static String stbdTen(int stationId, double currentSetpoint) =>
+      _build('STBDTEN', currentSetpoint, stationId);
+
+  static String reqCmd(int stationId) =>
+      _build('REQCMD', 0.0, stationId);
+
+  static String relCmd(int stationId) =>
+      _build('RELCMD', 0.0, stationId);
+
+  // ---------------------------------------------------------------------------
+  //  Private helpers
+  // ---------------------------------------------------------------------------
+
+  static String _build(String cmd, double value, int stationId) {
+    final body = 'PARP,$cmd,${value.toStringAsFixed(1)},'
+        '${stationId.toString().padLeft(2, '0')}';
+    final crc = _computeCrc(body);
+    return '\$$body*${crc.toRadixString(16).toUpperCase().padLeft(2, '0')}\r\n';
+  }
+
+  static int _computeCrc(String body) {
+    int crc = 0;
+    for (final ch in body.codeUnits) {
+      crc ^= ch;
+    }
+    return crc;
+  }
+
+  static bool _crcOk(String body, String crcHex) {
+    final expected = _computeCrc(body);
+    final received = int.tryParse(crcHex, radix: 16);
+    return received != null && received == expected;
+  }
+
+  static AutopilotMode _parseMode(String raw) => switch (raw) {
+        'HEADING_HOLD' => AutopilotMode.headingHold,
+        'TRACK' => AutopilotMode.trackKeep,
+        _ => AutopilotMode.standby,
+      };
+}