using UnityEngine;

/// <summary>
/// Makes this object follow a target (bottleTransform) horizontally, optionally using a wobble offset for vertical movement.
/// </summary>
public class RockFollower : MonoBehaviour
{
    [Header("References")]
    public Transform bottleTransform;
    public WobbleBehavior bottleWobble;

    [Header("Movement Settings")]
    public float followStiffness = 4f;
    /// <summary>
    /// Whether to use the wobble offset for vertical movement.
    /// </summary>
    public bool useWobbleOffset = true;
    /// <summary>
    /// The vertical distance between the rock and the bottle.
    /// </summary>
    [SerializeField] private float verticalDistance = 6f;

    private float velocityX; // For SmoothDamp

#if UNITY_EDITOR
    /// <summary>
    /// Called in editor when properties are changed.
    /// Updates the object's position when verticalDistance is modified.
    /// </summary>
    private void OnValidate()
    {
        // Only update position if playing or in prefab mode
        if (Application.isPlaying || UnityEditor.PrefabUtility.IsPartOfPrefabAsset(this))
            return;
            
        if (bottleTransform != null)
        {
            // Calculate the new Y position based on bottle's position and the updated verticalDistance
            float newY = bottleTransform.position.y - verticalDistance;
            
            // Apply the wobble offset if enabled
            if (useWobbleOffset && bottleWobble != null)
            {
                newY += bottleWobble.VerticalOffset;
            }
            
            // Update only the Y position, keeping X and Z unchanged
            transform.position = new Vector3(transform.position.x, newY, transform.position.z);
            
            // Mark the scene as dirty to ensure changes are saved
            UnityEditor.SceneManagement.EditorSceneManager.MarkSceneDirty(UnityEngine.SceneManagement.SceneManager.GetActiveScene());
        }
    }
#endif

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

        // Target horizontal position is bottle's X
        float targetX = bottleTransform.position.x;
        float currentX = transform.position.x;

        // Smoothly follow bottle's X with stiffer motion
        float newX = Mathf.SmoothDamp(currentX, targetX, ref velocityX, 1f / followStiffness);

        // Calculate Y position based on bottle's position and vertical distance
        float newY = bottleTransform.position.y - verticalDistance;
        if (useWobbleOffset && bottleWobble != null)
        {
            newY += bottleWobble.VerticalOffset;
        }

        // Set new position (only X and Y, keep Z)
        transform.position = new Vector3(newX, newY, transform.position.z);
    }
}