using UnityEngine;
using UnityEngine.UI;
using TMPro;

namespace Colosseum.UI
{
    /// <summary>
    /// 체력/마나 바 UI 컴포넌트
    /// Slider 또는 Image.Fill 방식 지원
    /// </summary>
    public class StatBar : MonoBehaviour
    {
        [Header("References - Slider 방식")]
        [SerializeField] private Slider slider;

        [Header("References - Fill Image 방식")]
        [SerializeField] private Image fillImage;

        [Header("References - 텍스트")]
        [SerializeField] private TMP_Text valueText;

        [Header("Colors")]
        [SerializeField] private Color fullColor = Color.green;
        [SerializeField] private Color lowColor = Color.red;
        [SerializeField] private float lowThreshold = 0.3f;
        [SerializeField] private bool useColorTransition = true;

        [Header("Animation")]
        [SerializeField] private bool smoothTransition = true;
        [SerializeField] private float lerpSpeed = 5f;

        private float currentValue;
        private float maxValue;
        private float displayValue;

        /// <summary>
        /// 바 값 설정
        /// </summary>
        public void SetValue(float current, float max)
        {
            currentValue = current;
            maxValue = max;

            if (!smoothTransition)
            {
                displayValue = currentValue;
            }
            
            // 항상 즉시 시각적 업데이트 수행
            UpdateVisuals();
        }

        private void Update()
        {
            if (smoothTransition && !Mathf.Approximately(displayValue, currentValue))
            {
                displayValue = Mathf.Lerp(displayValue, currentValue, lerpSpeed * Time.deltaTime);

                if (Mathf.Abs(displayValue - currentValue) < 0.01f)
                    displayValue = currentValue;

                UpdateVisuals();
            }
        }

        private void UpdateVisuals()
        {
            if (maxValue <= 0f)
            {
                Debug.LogWarning($"[StatBar:{gameObject.name}] UpdateVisuals: maxValue is {maxValue}, skipping");
                return;
            }

            float ratio = Mathf.Clamp01(displayValue / maxValue);

            // Slider 방식
            if (slider != null)
            {
                slider.value = ratio;

                // Slider 내부 Fill 이미지 색상 변경
                if (useColorTransition && slider.fillRect != null)
                {
                    var fillImg = slider.fillRect.GetComponent<Image>();
                    if (fillImg != null)
                    {
                        fillImg.color = ratio <= lowThreshold ? lowColor : fullColor;
                    }
                }
            }
            // Image.Fill 방식
            else if (fillImage != null)
            {
                fillImage.fillAmount = ratio;

                if (useColorTransition)
                {
                    fillImage.color = ratio <= lowThreshold ? lowColor : fullColor;
                }
            }

            // 텍스트
            if (valueText != null)
            {
                valueText.text = $"{Mathf.CeilToInt(displayValue)} / {Mathf.CeilToInt(maxValue)}";
            }
        }

        private void OnValidate()
        {
            if (slider == null)
                slider = GetComponentInChildren<Slider>();
            if (fillImage == null && slider == null)
                fillImage = GetComponentInChildren<Image>();
        }
    }
}