using UnityEngine;
using BigFloatNumerics;

public class HpBarHandler : MonoBehaviour, IOwnedComponent<Character>
{
    [SerializeField] Transform spawnPosition;
    [SerializeField] ExtendSlider barPrefab;

    public Character Owner { get; private set; }

    StatData hpStat;

    Camera mainCamera;
    Camera uiCamera;
    RectTransform barRoot;

    ExtendSlider barInstance;

    public void Initialize(Character owner)
    {
        Owner = owner;
        Owner.Data.TryGetStat(StatID.Hp, out hpStat);

        mainCamera = Camera.main;
        uiCamera = GameObject.FindGameObjectWithTag("UICamera").GetComponent<Camera>();
        barRoot = GameObject.FindGameObjectWithTag("HpBarRoot").GetComponent<RectTransform>();

        barInstance = Instantiate(barPrefab, barRoot);
    }

    private void OnDestroy()
    {
        if (Owner == null) return;

        if(barInstance != null && barInstance.gameObject != null)
            Destroy(barInstance.gameObject);
    }

    private void Update()
    {
        if (barInstance == null) return;

        if (Owner != null && hpStat != null)
        {
            barInstance.SetRate((BigFloat)Owner.CurrentHp / hpStat.Value);
        }
    }

    private void LateUpdate()
    {
        if(barInstance == null) return;

        var screenPos = mainCamera.WorldToScreenPoint(spawnPosition.position);
        RectTransformUtility.ScreenPointToLocalPointInRectangle(barRoot, screenPos, uiCamera, out Vector2 localPos);

        barInstance.transform.localPosition = localPos;
    }
}