using System.Collections; 
using UnityEngine;
using UnityEngine.Events;
using UnityEngine.EventSystems;
using UnityEngine.UIElements;

namespace XED.UI
{
    public class UI_ButtonDropdown : UnityEngine.MonoBehaviour, IDeselectHandler
    {
        [SerializeField] protected GameObject dropdownScrollview;
        [SerializeField] private UnityEvent onDeselect;
        [SerializeField] float openTime = 0.1f;
        private Vector3 closeScale = new Vector3(1, 0, 1);
        private bool isOpen = false;
        // Start is called before the first frame update
        void Awake()
        {
            dropdownScrollview.transform.localScale = closeScale;
            gameObject.AddComponent<MeshRenderer>();
        }
        public virtual void Open()
        {
            isOpen = !isOpen;
            StopAllCoroutines();
            if (isOpen) StartCoroutine(CoroutineOpen());
            else StartCoroutine(CoroutineClose());
        }
        public void Close()
        {
            isOpen = false;
            StopAllCoroutines();
            StartCoroutine(CoroutineClose());
        }
        public void OnDeselect(BaseEventData eventData)
        {
            onDeselect?.Invoke();
        }
        IEnumerator CoroutineOpen()
        {
            Vector3 currentScale = dropdownScrollview.transform.localScale;
            Vector3 destScale = Vector3.one;
            float time = 0;
            float rate = 0;
            while (time < openTime)
            {
                time += Time.deltaTime;
                rate = time > openTime ? 1.0f : time / openTime;
                dropdownScrollview.transform.localScale = Vector3.Lerp(currentScale, destScale, rate);
                yield return null;
            }
            yield return null;
        }
        IEnumerator CoroutineClose()
        {
            Vector3 currentScale = dropdownScrollview.transform.localScale;
            Vector3 destScale = closeScale;
            float time = 0;
            float rate = 0;
            yield return new WaitForSeconds(openTime);
            while (time < openTime)
            {
                time += Time.deltaTime;
                rate = time > openTime ? 1.0f : time / openTime;
                dropdownScrollview.transform.localScale = Vector3.Lerp(currentScale, destScale, rate);
                yield return null;
            }
            yield return null;
        }
    }
}