using UnityEngine;

public class WeaponBob : MonoBehaviour
{
    [Header("Bob Settings")]
    public float bobFrequency = 10f;
    public float bobHorizontalAmplitude = 0.05f;
    public float bobVerticalAmplitude = 0.03f;

    [Header("Sprint Multiplier")]
    public float sprintBobMultiplier = 1.5f;

    [Header("Smoothing")]
    public float returnSpeed = 6f;

    private Vector3 originalLocalPos;
    private float bobTimer = 0f;
    private CharacterController controller;

    void Start()
    {
        originalLocalPos = transform.localPosition;
        controller = GetComponentInParent<CharacterController>();
    }

    void Update()
    {
        if (controller == null) return;

        // Check if the player is moving on the ground
        Vector3 horizontalVelocity = new Vector3(controller.velocity.x, 0f, controller.velocity.z);
        bool isMoving = horizontalVelocity.magnitude > 0.5f && controller.isGrounded;

        if (isMoving)
        {
            float multiplier = Input.GetKey(KeyCode.LeftShift) ? sprintBobMultiplier : 1f;
            bobTimer += Time.deltaTime * bobFrequency * multiplier;

            float bobX = Mathf.Sin(bobTimer) * bobHorizontalAmplitude * multiplier;
            // Abs(Sin) means the weapon bounces UP on every step (left and right)
            // instead of looping in a circle/figure-8
            float bobY = Mathf.Abs(Mathf.Sin(bobTimer)) * bobVerticalAmplitude * multiplier;

            transform.localPosition = originalLocalPos + new Vector3(bobX, bobY, 0f);
        }
        else
        {
            // Don't reset bobTimer so the phase doesn't snap when you start moving again
            transform.localPosition = Vector3.Lerp(
                transform.localPosition,
                originalLocalPos,
                Time.deltaTime * returnSpeed
            );
        }
    }
}