using UnityEngine;

public class DamageIndicatorHandler : MonoBehaviour, IOwnedComponent<Character>
{
    struct DmgIndicatorProperty
    {
        public float fontSize;
        public Color color;
    }

    static readonly DmgIndicatorProperty _normalDmgIndicatorProp = new DmgIndicatorProperty { fontSize = 24f, color = new Color(1f, 1f, 1f) };
    static readonly DmgIndicatorProperty _criticalDmgIndicatorProp = new DmgIndicatorProperty { fontSize = 32f, color = new Color(1f, 56f / 255f, 0f) };

    Camera _mainCamera;
    Camera _uiCamera;
    RectTransform _indicatorRoot;

    [SerializeField] Transform spawnPosition;
    [SerializeField] DamageIndicatorText indicatorPrefab;

    public Character Owner { get; private set; }

    DynamicMonoObjectPool<DamageIndicatorText> indicatorPool;

    public void Initialize(Character owner)
    {
        Owner = owner;
        Owner.OnDamaged += OnDamaged;

        _mainCamera = Camera.main;
        _uiCamera = GameObject.FindGameObjectWithTag(GameProperty.Instance.UICameraTag).GetComponent<Camera>();
        _indicatorRoot = GameObject.FindGameObjectWithTag(GameProperty.Instance.DamageIndicatorRootTag).GetComponent<RectTransform>();

        indicatorPool = new();
        indicatorPool.Initialize(
            InstantiateIndicator, 
            DestroyIndicator, 
            (obj) => { obj.Hide(); }, 
            (obj) => {  },
            5);
    }

    private DamageIndicatorText InstantiateIndicator()
    {
        var indicator = Instantiate(indicatorPrefab, _indicatorRoot);
        indicator.OnComplete += indicatorPool.Return;
        return indicator;
    }

    private void DestroyIndicator(DamageIndicatorText indicator)
    {
        if (indicator == null || indicator.gameObject == null) return;
        Destroy(indicator.gameObject);
    }

    private void OnDamaged(Character _, Damage damage)
    {
        var indicator = indicatorPool.Get();

        if (damage.isCritical)
            indicator.SetText(FormatString.BigIntString1(damage.value), _criticalDmgIndicatorProp.fontSize, _criticalDmgIndicatorProp.color);
        else
            indicator.SetText(FormatString.BigIntString1(damage.value), _normalDmgIndicatorProp.fontSize, _normalDmgIndicatorProp.color);

        var screenPos = _mainCamera.WorldToScreenPoint(spawnPosition.position);
        RectTransformUtility.ScreenPointToLocalPointInRectangle(_indicatorRoot, screenPos, _uiCamera, out Vector2 localPos);
        indicator.transform.localPosition = localPos;

        indicator.Show();
    }

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

        Owner.OnDamaged -= OnDamaged;
        indicatorPool.Dispose();
    }
}