decay-grid/Assets/Scripts/Infrastructure/Unity/PlayerController.cs

using System;
using KBCore.Refs;
using UnityEngine;
using UnityEngine.InputSystem;

namespace Infrastructure.Unity
{
    [RequireComponent(typeof(Rigidbody))]
    public class PlayerController : MonoBehaviour
    {
        [Header("Movement Settings")]
        [SerializeField]
        private float moveSpeed = 8f;
        [SerializeField] private float maxVelocityChange = 10f;
        [SerializeField] private float snapForce = 15f;
        
        [Header("Interaction")]
        [SerializeField] private LayerMask tileLayer;
        [SerializeField] private float groundCheckDistance = 1.5f;
        
        [Self] [SerializeField] private Rigidbody rb;
        
        private InputSystem_Actions _actions;
        private Vector2 _moveInput;
        
        public Rigidbody Rigidbody => rb;

        private void OnEnable()
        {
            _actions.Player.Enable();
            
            _actions.Player.Move.performed += OnMovePerformed;
            _actions.Player.Move.canceled += OnMoveCanceled;
        }

        private void OnDisable()
        {
            _actions.Player.Move.performed -= OnMovePerformed;
            _actions.Player.Move.canceled -= OnMoveCanceled;
            
            _actions.Player.Disable();
        }

        private void Awake()
        {
            _actions = new InputSystem_Actions();
            
            rb.freezeRotation = true;
            rb.useGravity = true;
        }

        private void FixedUpdate()
        {
            HandleMovement();
            DetectGround();
        }

        private void HandleMovement()
        {
            var targetVelocity = Vector3.zero;
            var snapAxis = Vector3.zero;

            if (_moveInput.sqrMagnitude > 0.1f)
            {
                if (Mathf.Abs(_moveInput.x) > Mathf.Abs(_moveInput.y))
                {
                    targetVelocity = new Vector3(_moveInput.x > 0 ? moveSpeed : -moveSpeed, 0, 0);
                    snapAxis = Vector3.forward;
                }
                else
                {
                    targetVelocity = new Vector3(0, 0, _moveInput.y > 0 ? moveSpeed : -moveSpeed);
                    snapAxis = Vector3.right;
                }
            }

            var velocity = rb.linearVelocity;
            var velocityChange = (targetVelocity - velocity);
            
            velocityChange.x = Mathf.Clamp(velocityChange.x, -maxVelocityChange, maxVelocityChange);
            velocityChange.z = Mathf.Clamp(velocityChange.z, -maxVelocityChange, maxVelocityChange);
            velocityChange.y = 0f;
            
            rb.AddForce(velocityChange, ForceMode.VelocityChange);

            if (snapAxis != Vector3.zero)
            {
                ApplySnapping(snapAxis);
            }
            else
            {
                ApplySnapping(Vector3.right);
                ApplySnapping(Vector3.forward);
            }
        }
        
        private void ApplySnapping(Vector3 axis)
        {
            var currentPos = Vector3.Dot(transform.position, axis);
            var targetPos = Mathf.Round(currentPos);
            
            var diff = targetPos - currentPos;
            
            var correction = axis * (diff * snapForce);
            rb.AddForce(correction, ForceMode.Acceleration);
        }

        private void DetectGround()
        {
            if (Physics.Raycast(transform.position, Vector3.down, out var hit, groundCheckDistance, tileLayer))
            {
                if (hit.collider.TryGetComponent<TileViewAdapter>(out var tileAdapter))
                {
                    tileAdapter.OnPlayerStep();
                }
            }
        }

        private void OnMovePerformed(InputAction.CallbackContext ctx)
        {
            _moveInput = ctx.ReadValue<Vector2>();
        }

        private void OnMoveCanceled(InputAction.CallbackContext ctx)
        {
            _moveInput = Vector2.zero;
        }
    }
}