// Copyright (c) FIRST and other WPILib contributors.
// Open Source Software; you can modify and/or share it under the terms of
// the WPILib BSD license file in the root directory of this project.

package frc4388.robot.subsystems;

import edu.wpi.first.math.geometry.Translation2d;
import edu.wpi.first.math.kinematics.ChassisSpeeds;
import edu.wpi.first.math.kinematics.SwerveDriveKinematics;
import edu.wpi.first.math.kinematics.SwerveModuleState;
import edu.wpi.first.math.util.Units;
import edu.wpi.first.wpilibj2.command.SubsystemBase;
import frc4388.robot.Constants.SwerveDriveConstants;

public class SwerveDrive extends SubsystemBase {
  
  public SwerveModule leftFront;
  public SwerveModule rightFront;
  public SwerveModule leftBack;
  public SwerveModule rightBack;

  private SwerveModule[] modules;

  private Translation2d leftFrontLocation = new Translation2d(Units.inchesToMeters(SwerveDriveConstants.HALF_HEIGHT), Units.inchesToMeters(SwerveDriveConstants.HALF_WIDTH));
  private Translation2d rightFrontLocation = new Translation2d(Units.inchesToMeters(SwerveDriveConstants.HALF_HEIGHT), -Units.inchesToMeters(SwerveDriveConstants.HALF_WIDTH));
  private Translation2d leftBackLocation = new Translation2d(-Units.inchesToMeters(SwerveDriveConstants.HALF_HEIGHT), Units.inchesToMeters(SwerveDriveConstants.HALF_WIDTH));
  private Translation2d rightBackLocation = new Translation2d(-Units.inchesToMeters(SwerveDriveConstants.HALF_HEIGHT), -Units.inchesToMeters(SwerveDriveConstants.HALF_WIDTH));
  
  private SwerveDriveKinematics kinematics = new SwerveDriveKinematics(leftFrontLocation, rightFrontLocation, leftBackLocation, rightBackLocation); 

  // private SwerveDriveOdometry odometry = new SwerveDrive(
  //   kinematics, 
  //   gyro.getRotation2d(),
  //   new SwerveModulePosition[] {
  //     leftFront.getPosition(),
  //     rightFront.getPosition(),
  //     leftBack.getPosition(),
  //     rightBack.getPosition()
  //   }
  // );

  public double speedAdjust = SwerveDriveConstants.Conversions.JOYSTICK_TO_METERS_PER_SECOND_SLOW; // * slow by default

  /** Creates a new SwerveDrive. */
  public SwerveDrive(SwerveModule leftFront, SwerveModule rightFront, SwerveModule leftBack, SwerveModule rightBack) {//, RobotGyro gyro) {
    this.leftFront = leftFront;
    this.rightFront = rightFront;
    this.leftBack = leftBack;
    this.rightBack = rightBack;

    this.modules = new SwerveModule[] {this.leftFront, this.rightFront, this.leftBack, this.rightBack};
  }

  // WPILib swerve drive example
  public void drive(double xSpeed, double ySpeed, double rot, boolean fieldRelative) {
    // SwerveModuleState[] states = kinematics.toSwerveModuleStates(
    //   fieldRelative ? ChassisSpeeds.fromFieldRelativeSpeeds(xSpeed, ySpeed, rot, gyro.getRotation2d()) 
    //                 : new ChassisSpeeds(xSpeed, ySpeed, rot)
    // );
    SwerveModuleState[] states = kinematics.toSwerveModuleStates(new ChassisSpeeds(xSpeed, ySpeed, rot * SwerveDriveConstants.ROTATION_SPEED));
    setModuleStates(states);
  }

  /**
   * Set each module of the swerve drive to the corresponding desired state.
   * @param desiredStates Array of module states to set.
   */
  public void setModuleStates(SwerveModuleState[] desiredStates) {
    SwerveDriveKinematics.desaturateWheelSpeeds(desiredStates, Units.metersToFeet(SwerveDriveConstants.MAX_SPEED_FEET_PER_SECOND));
    for (int i = 0; i < desiredStates.length; i++) {
      SwerveModule module = modules[i];
      SwerveModuleState state = desiredStates[i];
      module.setDesiredState(state);
    }
  }

  /**
   * Updates the odometry of the SwerveDrive.
   */
  // public void updateOdometry() {
  //   odometry.update(
  //     gyro.getRotation2d(), 
  //     new SwerveModulePosition[] {
  //       leftFront.getPosition(),
  //       rightFront.getPosition(),
  //       leftBack.getPosition(),
  //       rightBack.getPosition()
  //     }
  //   );
  // }

  /**
   * Gets the odometry of the SwerveDrive.
   * @return The odometry of the SwerveDrive as a Pose2d object (xMeters, yMeters, theta).
   */
  // public Pose2d getOdometry() {
  //   return odometry.getPoseMeters();
  // }

  /**
   * Sets the odometry of the SwerveDrive.
   * @param pose Pose to set the odometry to.
   */
  // public void setOdometry(Pose2d pose) {
  //   odometry.resetPosition(
  //     gyro.getRotation2d(), 
  //     new SwerveModulePosition[] {
  //       leftFront.getPosition(),
  //       rightFront.getPosition(),
  //       leftBack.getPosition(),
  //       rightBack.getPosition()
  //     },
  //     pose
  //   );
  // }

  /**
   * Resets the odometry of the SwerveDrive to 0.
   * *NOTE: If you reset your gyroscope or wheel encoders, this method MUST be called with the new gyro angle and wheel encoder positions.
   */
  // public void resetOdometry() {
  //   odometry.resetPosition(
  //     gyro.getRotation2d(), 
  //     new SwerveModulePosition[] {
  //       leftFront.getPosition(),
  //       rightFront.getPosition(),
  //       leftBack.getPosition(),
  //       rightBack.getPosition()
  //     },
  //     new Pose2d()
  //   );
  // }

  public SwerveDriveKinematics getKinematics() {
    return this.kinematics;
  }

  @Override
  public void periodic() {
    // This method will be called once per scheduler run
    // updateOdometry();
  }

  /**
   * Shifts gear from high to low, or vice versa.
   * @param shift true to shift to high, false to shift to low
   */
  public void highSpeed(boolean shift) {
    this.speedAdjust = shift ? SwerveDriveConstants.Conversions.JOYSTICK_TO_METERS_PER_SECOND_FAST : SwerveDriveConstants.Conversions.JOYSTICK_TO_METERS_PER_SECOND_SLOW;
  }

}