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[3501/stronghold-2016] / src / org / usfirst / frc / team3501 / robot / subsystems / Shooter.java

package org.usfirst.frc.team3501.robot.subsystems;

import org.usfirst.frc.team3501.robot.Constants;
import org.usfirst.frc.team3501.robot.Lidar;

import edu.wpi.first.wpilibj.CANTalon;
import edu.wpi.first.wpilibj.CounterBase.EncodingType;
import edu.wpi.first.wpilibj.DoubleSolenoid;
import edu.wpi.first.wpilibj.Encoder;
import edu.wpi.first.wpilibj.command.PIDSubsystem;

/***
 * The Shooter consists of a platform and wheel, each controlled by separate
 * motors. The piston controlling the platform pushes the ball onto the wheel.
 * The wheel is controlled by a motor, which is running before the ball is
 * pushed onto the wheel. The spinning wheel propels the ball.
 *
 * @author superuser
 *
 *         setPoint (in the context of shooter) is the target value we want the
 *         PID controller to adjust the system to, for example, if we want the
 *         shooter wheels to run at 10in/s
 *
 */

public class Shooter extends PIDSubsystem {
  // Shooter PID Proportional Constants P, I, and D
  private static double sp = 0.015, si = 0, sd = 0;

  // PID Controller tolerance for the error
  private static double encoderTolerance = 5.0;
  private static double pidOutput = 5.0;

  private CANTalon shooter;
  private DoubleSolenoid hood, punch;
  private Encoder encoder;
  private Lidar lidar;

  public Shooter() {
    super(sp, si, sd);

    shooter = new CANTalon(Constants.Shooter.PORT);
    hood = new DoubleSolenoid(Constants.Shooter.HOOD_FORWARD,
        Constants.Shooter.HOOD_REVERSE);
    punch = new DoubleSolenoid(Constants.Shooter.PUNCH_FORWARD,
        Constants.Shooter.PUNCH_REVERSE);

    encoder = new Encoder(Constants.Shooter.ENCODER_PORT_A,
        Constants.Shooter.ENCODER_PORT_B, false, EncodingType.k4X);

    lidar = new Lidar(Constants.Shooter.LIDAR_I2C_PORT);
  }

  /***
   * This method checks to see if the ball has successfully passed through the
   * intake rollers and is inside.
   *
   * @return whether the presence of the ball is true or false and returns the
   *         state of the condition (true or false).
   */

  public boolean isBallInside() {
    return true;
  }

  public void setSpeed(double speed) {
    setShooterPID();
    setSetpoint(speed);
  }

  // This getDistance() will return the distance using the lidar from the
  // desired target during match. This distance is returned in units of
  // CENTIMETERS.
  public double getDistance() {
    return lidar.getDistance();
  }

  public void stop() {
    this.setSpeed(0.0);
  }

  public double getSpeed() {
    return encoder.getRate(); // in/sec
  }

  // Use negative # for decrement. Positive for increment.

  public void changeSpeed(double change) {
    double newSpeed = getSpeed() + change;
    setSpeed(newSpeed);
  }

  // Punch Commands
  public void punch() {
    punch.set(Constants.Shooter.punch);
  }

  public void retractPunch() {
    punch.set(Constants.Shooter.retract);
  }

  public boolean isHoodOpen() {
    return hood.get() == Constants.Shooter.open;
  }

  public void openHood() {
    hood.set(Constants.Shooter.open);
  }

  public void closeHood() {
    hood.set(Constants.Shooter.closed);
  }

  @Override
  protected void initDefaultCommand() {
  }

  @Override
  protected double returnPIDInput() {
    return sensorFeedback();
  }

  /*
   * Method is a required method that the PID Subsystem uses to return the
   * calculated PID value to the driver
   * 
   * @param Gives the user the output from the PID algorithm that is calculated
   * internally
   */
  @Override
  protected void usePIDOutput(double output) {
    shooter.set(output);
    pidOutput = output;
  }

  private double sensorFeedback() {
    return this.getSpeed();
  }

  public void setShooterPID() {
    this.updatePID();
    this.setAbsoluteTolerance(encoderTolerance);
    this.setOutputRange(-1.0, 1.0);
    this.setInputRange(-500.0, 500.0);
    this.enable();
  }

  // Updates the PID constants
  public void updatePID() {
    this.getPIDController().setPID(sp, si, sd);
  }
}