Stair_Horror/Assets/Scripts/PlayerController.cs

using UnityEngine;
using UnityEngine.InputSystem; 

public class PlayerController : MonoBehaviour
{
    [Header("Movement")]
    public float moveSpeed = 5f;
    public float gravity = -9.81f; // Standard Earth gravity
    public float jumpHeight = 1.0f; // Optional, set to 0 if no jumping allowed

    [Header("Look Settings")]
    public float mouseSensitivity = 10f;
    public float maxLookAngle = 70f; 

    [Header("Interaction")]
    public float interactionDistance = 3f;
    public LayerMask interactionLayer;

    // Components
    private CharacterController controller;
    private Transform cameraTransform;
    
    // State
    private float verticalRotation = 0f;
    private Vector3 velocity; // Stores our falling speed
    private bool isGrounded;  // Are we touching the floor?
    
    // Inputs
    private InputSystem_Actions inputActions;
    private Vector2 moveInput;

    void Awake()
    {
        inputActions = new InputSystem_Actions();
        controller = GetComponent<CharacterController>();
        cameraTransform = Camera.main.transform;
        
        Cursor.lockState = CursorLockMode.Locked;
        Cursor.visible = false;

        // Bind Inputs
        inputActions.Player.Move.performed += ctx => moveInput = ctx.ReadValue<Vector2>();
        inputActions.Player.Move.canceled += ctx => moveInput = Vector2.zero;
        inputActions.Player.Interact.started += ctx => TryInteract();
    }

    void OnEnable() => inputActions.Enable();
    void OnDisable() => inputActions.Disable();

    void Update()
    {
        HandleGravity(); // <--- NEW GRAVITY FUNCTION
        HandleMovement();
        HandleLook();
        UpdateInteractionUI(); 
    }

    void HandleGravity()
    {
        // Check if the controller thinks it's on the ground
        isGrounded = controller.isGrounded;

        if (isGrounded && velocity.y < 0)
        {
            // Reset falling speed when on ground (keep slightly negative to stick to floor)
            velocity.y = -2f;
        }

        // Apply Gravity over time
        velocity.y += gravity * Time.deltaTime;

        // Apply the velocity to the controller
        controller.Move(velocity * Time.deltaTime);
    }

    void HandleMovement()
    {
        Vector3 move = transform.right * moveInput.x + transform.forward * moveInput.y;
        controller.Move(move * moveSpeed * Time.deltaTime);
    }

    // ... (Keep HandleLook, UpdateInteractionUI, and TryInteract exactly the same as before)
    // For brevity, I am not pasting the repeated Look/Interact code here, 
    // but ensure you keep those functions in your file! 
    // If you need the full paste again, let me know.
    
    // ------------------------------------------------------------------------
    // PASTE YOUR HandleLook, UpdateInteractionUI, and TryInteract HERE
    // ------------------------------------------------------------------------
    
    void HandleLook()
    {
        Vector2 rawInput = inputActions.Player.Look.ReadValue<Vector2>();
        float mouseX = rawInput.x * mouseSensitivity * Time.deltaTime;
        float mouseY = rawInput.y * mouseSensitivity * Time.deltaTime;

        verticalRotation -= mouseY;
        verticalRotation = Mathf.Clamp(verticalRotation, -maxLookAngle, maxLookAngle);

        cameraTransform.localRotation = Quaternion.Euler(verticalRotation, 0f, 0f);
        transform.Rotate(Vector3.up * mouseX);
    }

    void UpdateInteractionUI()
    {
        Ray ray = new Ray(cameraTransform.position, cameraTransform.forward);
        RaycastHit hit;

        if (Physics.Raycast(ray, out hit, interactionDistance, interactionLayer))
        {
            IInteractable interactable = hit.collider.GetComponent<IInteractable>();
            if (interactable != null && InteractionUI.Instance != null)
                InteractionUI.Instance.UpdatePrompt(interactable.GetDescription());
            else if (InteractionUI.Instance != null)
                InteractionUI.Instance.ClearPrompt();
        }
        else if (InteractionUI.Instance != null) InteractionUI.Instance.ClearPrompt();
    }

    void TryInteract()
    {
        Ray ray = new Ray(cameraTransform.position, cameraTransform.forward);
        RaycastHit hit;
        if (Physics.Raycast(ray, out hit, interactionDistance, interactionLayer))
        {
            IInteractable interactable = hit.collider.GetComponent<IInteractable>();
            if (interactable != null)
            {
                interactable.Interact();
                if (InteractionUI.Instance != null) 
                    InteractionUI.Instance.UpdatePrompt(interactable.GetDescription());
            }
        }
    }
}