public class RobotContainer {

    private final DriveSubsystem  m_drive  = new DriveSubsystem();
    private final IntakeSubsystem m_intake = new IntakeSubsystem();
    private final ArmSubsystem    m_arm    = new ArmSubsystem();

    // ── Autonomous chooser ─────────────────────────────────────────────────
    // Generic type is Command — each option is a complete auto Command.
    private final SendableChooser<Command> m_autoChooser =
        new SendableChooser<>();

    public RobotContainer() {
        configureAutoChooser();
        configureButtonBindings();
    }

    private void configureAutoChooser() {

        // ── Default option: always safe, always works ──────────────────────
        // setDefaultOption() is what runs if the drive team forgets to select.
        // It must be something the robot can execute reliably from ANY starting position.
        // "Drive forward" meets this bar. A complex multi-piece routine does not.
        m_autoChooser.setDefaultOption(
            "Drive Forward (Safe Default)",
            new DriveDistanceCommand(m_drive, 2.0, 0.4).withTimeout(4.0));

        // ── Additional options: strategy-specific ──────────────────────────
        m_autoChooser.addOption(
            "Two Piece — Left Side",
            getTwoPieceLeftAuto());

        m_autoChooser.addOption(
            "Two Piece — Right Side",
            getTwoPieceRightAuto());

        m_autoChooser.addOption(
            "Score One + Play Defense",
            getScoreAndDefenseAuto());

        m_autoChooser.addOption(
            "Timed Fallback (Sensor Failure)",
            getTimedFallbackAuto());

        m_autoChooser.addOption(
            "Do Nothing",
            Commands.none());

        // ── Publish to SmartDashboard ──────────────────────────────────────
        // This creates the dropdown widget the drive team sees.
        // The string key "Auto Mode" must be consistent — if you change it,
        // saved Shuffleboard layouts won't find the widget anymore.
        SmartDashboard.putData("Auto Mode", m_autoChooser);
    }

    public Command getAutonomousCommand() {
        // getSelected() returns the Command mapped to the current dropdown selection.
        // If no selection was made (shouldn't happen with setDefaultOption), returns null.
        // Robot.java's null check before scheduling handles this edge case.
        return m_autoChooser.getSelected();
    }

    // Private builder methods — each returns a fresh Command instance.
    private Command getTwoPieceLeftAuto() {
        return Commands.sequence( /* ... */ );
    }
    private Command getTwoPieceRightAuto() {
        return Commands.sequence( /* ... */ );
    }
    private Command getScoreAndDefenseAuto() {
        return Commands.sequence( /* ... */ );
    }
    private Command getTimedFallbackAuto() {
        return Commands.run(
            () -> m_drive.arcadeDrive(0.4, 0), m_drive)
            .withTimeout(1.5);
    }
}

// ❌ WRONG: captured at construction time, ignores dashboard selection
public RobotContainer() {
    configureAutoChooser();
    m_selectedAuto = m_autoChooser.getSelected(); // always returns default
}
public Command getAutonomousCommand() {
    return m_selectedAuto;  // always the default — selection ignored
}

// ✅ CORRECT: called at autonomousInit() time, after selection is final
public Command getAutonomousCommand() {
    return m_autoChooser.getSelected();
}

// After configuring AutoBuilder in your drivetrain subsystem:

private final SendableChooser<Command> m_autoChooser =
    AutoBuilder.buildAutoChooser();
// ↑ Scans deploy/pathplanner/autos/ for .auto files automatically.
//   Every .auto file appears as a chooser option without any addOption() calls.

public RobotContainer() {
    // Register named commands so PathPlanner event markers
    // can trigger robot actions at specific path waypoints.
    NamedCommands.registerCommand("intake", new IntakeUntilSensorCommand(m_intake));
    NamedCommands.registerCommand("shoot", new ShootCommand(m_shooter));

    SmartDashboard.putData("Auto Mode", m_autoChooser);
}

public Command getAutonomousCommand() {
    return m_autoChooser.getSelected();
}