using System;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

[RequireComponent(typeof(Button))]
public class ExtendButton : MonoBehaviour, IPointerDownHandler, IPointerUpHandler
{
    [SerializeField] Button button;
    [SerializeField] float pressedInternalTime = 0.5f;
    [SerializeField] float pressedTickIntervalTime = 0.1f;

    bool isPressed;
    float pressedTime;
    float prevCallPressedEventTime;

    public Button ButtonComponent => button;

    public event Action OnPressedShortly;
    public event Action OnLongPressed;
    public event Action OnLongPressedReleased;

    private void OnEnable()
    {
        prevCallPressedEventTime = 0;
        pressedTime = 0;
        isPressed = false;
    }

    private void OnDisable()
    {
        prevCallPressedEventTime = 0;
        pressedTime = 0;
        isPressed = false;
    }

    private void LateUpdate()
    {
        if (!isPressed) return;

        if (Time.time >= prevCallPressedEventTime)
        {
            OnLongPressed?.Invoke();
            prevCallPressedEventTime += pressedTickIntervalTime;
        }
    }

    public void OnPointerDown(PointerEventData eventData)
    {
        if(!button.interactable) return;

        isPressed = true;
        pressedTime = Time.time;
        prevCallPressedEventTime = pressedTime + pressedInternalTime;
    }

    public void OnPointerUp(PointerEventData eventData)
    {
        if (pressedTime + pressedInternalTime <= Time.time)
            OnLongPressedReleased?.Invoke();
        else
            OnPressedShortly?.Invoke();

        prevCallPressedEventTime = 0;
        pressedTime = 0;
        isPressed = false;
    }

    private void OnValidate()
    {
        if (button == null)
            button = GetComponent<Button>();
    }
}