moving platform

using System.Collections;
using System.Collections.Generic;
using System.Net;
using UnityEngine;

public class MovingPlatform : MonoBehaviour
{
    public Transform posA, posB;
    public Transform platform;
    public float speed;
    Vector3 targetPos;
    
    public PlayerMovement playerMovement;
    Rigidbody2D rb;
    Vector3 moveDirection;

    private void Awake()
    {
        playerMovement = GameObject.FindGameObjectWithTag("Player").GetComponent<PlayerMovement>();
        rb = GetComponent<Rigidbody2D>();
    }

    private void OnDrawGizmos()
    {
        if (platform != null && posB != null && posA != null)
        {
            Gizmos.DrawLine(platform.transform.position, posB.position);
            Gizmos.DrawLine(platform.transform.position, posA.position);
        }
    }

    private void Start()
    {
        targetPos = posB.position;
        DirectionCalculate();
    }

    private void Update()
    {
        if (Vector2.Distance(transform.position, posA.position) < 0.05f)
        {
            targetPos = posB.position;
            DirectionCalculate();
        }
        if (Vector2.Distance(transform.position, posB.position) < 0.05f)
        {
            targetPos = posA.position;
            DirectionCalculate();
        }

        //transform.position = Vector3.MoveTowards(transform.position, targetPos, speed * Time.deltaTime);
    }

    private void FixedUpdate()
    {
        rb.velocity = moveDirection * speed;
    }

    void DirectionCalculate()
    {
        moveDirection = (targetPos - transform.position).normalized;
    }

    private void OnTriggerEnter2D(Collider2D collision)
    {
        if (collision.CompareTag("Player"))
        {
            playerMovement.platformRb = rb;
            playerMovement.isOnPlatform = true;
        }
    }

    private void OnTriggerExit2D(Collider2D collision)
    {
        if (collision.CompareTag("Player"))
        {
            collision.transform.parent = null;
            playerMovement.isOnPlatform = false;
        }
    }
}