using UnityEngine;
using UnityEngine.UI;
using TMPro;

namespace Beyond
{
    public class NavigationIndicator : MonoBehaviour
    {
        [Header("UI Elements")]
        [SerializeField] private Image indicatorImage; // Sprite na ekranie
        [SerializeField] private CanvasGroup canvasGroup; // Kontrola widoczno�ci
        [SerializeField] private TextMeshProUGUI distanceText; // Tekst odleg�o�ci
        [SerializeField] private Sprite defaultSprite;
        [SerializeField] private Sprite edgeSpriteLeft;
        [SerializeField] private Sprite edgeSpriteRight;
        [SerializeField] private Sprite edgeSpriteTop;
        [SerializeField] private Sprite edgeSpriteBottom;

        [Header("Settings")]
        [SerializeField] private float edgeBufferHeight = 50f; // Odleg�o�� od kraw�dzi ekranu w pionie
        [SerializeField] private float edgeBufferWidth = 50f; // Odleg�o�� od kraw�dzi ekranu w poziomie

        private Camera mainCamera;
        private Transform targetTransform;
        private float distanceToTarget;
        private bool isActive;

        private void Awake()
        {
            if (indicatorImage != null)
                indicatorImage.sprite = defaultSprite;

            canvasGroup = GetComponent<CanvasGroup>();
            if (canvasGroup != null)
                canvasGroup.alpha = 0f;

            mainCamera = Camera.main;
        }

        private void Update()
        {
            if (targetTransform != null && isActive)
            {
                UpdateIndicator();
            }
        }

        public void SetTargetTransform(Transform target)
        {
            targetTransform = target;
            isActive = true;
            if (canvasGroup != null)
                canvasGroup.alpha = 1f;
        }

        public void Deactivate()
        {
            isActive = false;
            if (canvasGroup != null)
                canvasGroup.alpha = 0f;
        }

        private void UpdateIndicator()
        {
            if (mainCamera == null || targetTransform == null) return;

            Vector3 targetPosition = targetTransform.position;
            Vector3 screenPos = mainCamera.WorldToScreenPoint(targetPosition);

            distanceToTarget = Vector3.Distance(mainCamera.transform.position, targetPosition);
            if (distanceText != null)
            {
                distanceText.text = $"[ {(int)distanceToTarget} m ]";
            }



            // Handle indicator position on screen edge
            Vector2 clampedPosition = ClampToScreenEdge(screenPos);
            transform.position = clampedPosition;

            // Change sprite based on screen edge position
            if (indicatorImage != null)
            {
                if (clampedPosition.x <= edgeBufferWidth)
                {
                    indicatorImage.sprite = edgeSpriteLeft;
                }
                else if (clampedPosition.x >= Screen.width - edgeBufferWidth)
                {
                    indicatorImage.sprite = edgeSpriteRight;
                }
                else if (clampedPosition.y <= edgeBufferHeight)
                {
                    indicatorImage.sprite = edgeSpriteTop;
                }
                else if (clampedPosition.y >= Screen.height - edgeBufferHeight)
                {
                    indicatorImage.sprite = edgeSpriteBottom;
                }
                else
                {
                    indicatorImage.sprite = defaultSprite;
                }
            }
        }

        private Vector2 ClampToScreenEdge(Vector3 screenPos)
        {
            if (screenPos.z < 0f)
            {
                if (screenPos.x > 0)
                {
                    screenPos.x = 0;
                }
                else
                {
                    screenPos.x = Screen.width;
                }
                screenPos.y = Screen.height - screenPos.y;

            }
            Vector2 screenPosEdgeClamp = screenPos;

            if (screenPos.x < edgeBufferWidth)
            {
                screenPosEdgeClamp.x = edgeBufferWidth;
            }
            else if (screenPos.x > Screen.width - edgeBufferWidth)
            {
                screenPosEdgeClamp.x = Screen.width - edgeBufferWidth;
            }

            if (screenPos.y < edgeBufferHeight)
            {
                screenPosEdgeClamp.y = edgeBufferHeight;
            }
            else if (screenPos.y > Screen.height - edgeBufferHeight)
            {
                screenPosEdgeClamp.y = Screen.height - edgeBufferHeight;
            }

            return screenPosEdgeClamp;
        }
    }
}