using UnityEngine;
using UnityEngine.UI;
using Pixelplacement;

namespace Utils.UI
{
    /// <summary>
    /// UI component that animates a screenshot flying away and disappearing.
    /// Uses Pixelplacement Tween library for smooth animations with curves.
    /// Attach to a UI prefab with frame (Image) and picture (Image) components.
    /// </summary>
    public class ScreenshotFlyawayAnimation : MonoBehaviour
    {
        [Header("UI Components")]
        [SerializeField] private Image _frame;
        [SerializeField] private Image _picture;
        
        [Header("Animation Settings")]
        [Tooltip("Target offset from starting position (in UI space)")]
        [SerializeField] private Vector2 _targetOffset = new Vector2(0, 300f);
        
        [Tooltip("Number of full rotations during animation")]
        [SerializeField] private float _spinRotations = 2f;
        
        [Tooltip("Duration of the entire animation in seconds")]
        [SerializeField] private float _duration = 1.5f;
        
        [Tooltip("Movement curve for position animation")]
        [SerializeField] private AnimationCurve _moveCurve = AnimationCurve.EaseInOut(0, 0, 1, 1);
        
        [Tooltip("Scale curve for shrinking animation")]
        [SerializeField] private AnimationCurve _scaleCurve = AnimationCurve.EaseInOut(0, 1, 1, 0);
        
        [Tooltip("Rotation curve for spinning animation")]
        [SerializeField] private AnimationCurve _rotationCurve = AnimationCurve.Linear(0, 0, 1, 1);
        
        private RectTransform _rectTransform;
        private bool _isAnimating;
        private Transform _targetTransform; // Target to fly toward (optional)
        
        private void Awake()
        {
            _rectTransform = GetComponent<RectTransform>();
            
            // Hide initially - will be shown when animation plays
            gameObject.SetActive(false);
            
            // Validate components
            if (_frame == null)
            {
                Debug.LogWarning("[ScreenshotFlyawayAnimation] Frame image not assigned!");
            }
            
            if (_picture == null)
            {
                Debug.LogWarning("[ScreenshotFlyawayAnimation] Picture image not assigned!");
            }
        }
        
        /// <summary>
        /// Start the flyaway animation with the captured screenshot texture.
        /// Unparents to root canvas to survive viewfinder destruction.
        /// </summary>
        /// <param name="photo">The screenshot texture to display</param>
        /// <param name="target">Optional target transform to fly toward (if null, uses _targetOffset)</param>
        public void PlayAnimation(Texture2D photo, Transform target = null)
        {
            if (_isAnimating)
            {
                Debug.LogWarning("[ScreenshotFlyawayAnimation] Animation already playing!");
                return;
            }
            
            if (photo == null)
            {
                Debug.LogError("[ScreenshotFlyawayAnimation] Photo texture is null!");
                Destroy(gameObject);
                return;
            }
            
            // Store target for StartAnimation
            _targetTransform = target;
            
            // Show the GameObject before playing animation
            gameObject.SetActive(true);
            
            // Unparent to root canvas to survive viewfinder destruction
            Canvas rootCanvas = GetComponentInParent<Canvas>();
            if (rootCanvas != null)
            {
                rootCanvas = rootCanvas.rootCanvas;
                transform.SetParent(rootCanvas.transform, worldPositionStays: true);
            }
            
            // Assign texture to picture image
            if (_picture != null)
            {
                Sprite photoSprite = Sprite.Create(
                    photo,
                    new Rect(0, 0, photo.width, photo.height),
                    new Vector2(0.5f, 0.5f)
                );
                _picture.sprite = photoSprite;
            }
            
            _isAnimating = true;
            StartAnimation();
        }
        
        /// <summary>
        /// Execute the animation using Pixelplacement Tween
        /// </summary>
        private void StartAnimation()
        {
            if (_rectTransform == null) return;
            
            // Get starting position
            Vector2 startPosition = _rectTransform.anchoredPosition;
            Vector2 endPosition;
            
            // Calculate end position based on target or offset
            if (_targetTransform != null)
            {
                // Convert target world position to local anchored position
                RectTransform targetRect = _targetTransform as RectTransform;
                if (targetRect != null && _rectTransform.parent is RectTransform parentRect)
                {
                    // Convert target's position to parent's local space
                    Vector2 targetLocalPos;
                    RectTransformUtility.ScreenPointToLocalPointInRectangle(
                        parentRect,
                        RectTransformUtility.WorldToScreenPoint(null, targetRect.position),
                        null,
                        out targetLocalPos
                    );
                    endPosition = targetLocalPos;
                }
                else
                {
                    // Fallback: use offset if conversion fails
                    endPosition = startPosition + _targetOffset;
                }
            }
            else
            {
                // Use offset if no target provided
                endPosition = startPosition + _targetOffset;
            }
            
            // Start rotation at 0
            Vector3 startRotation = Vector3.zero;
            Vector3 endRotation = new Vector3(0, 0, 360f * _spinRotations);
            
            // Start scale at 1
            Vector3 startScale = Vector3.one;
            Vector3 endScale = Vector3.zero;
            
            // Animate position using AnchoredPosition for UI
            Tween.AnchoredPosition(
                _rectTransform,
                startPosition,
                endPosition,
                _duration,
                0f, // no delay
                _moveCurve,
                Tween.LoopType.None,
                null, // no start callback
                OnAnimationComplete // complete callback
            );
            
            // Animate scale
            Tween.LocalScale(
                transform,
                startScale,
                endScale,
                _duration,
                0f,
                _scaleCurve
            );
            
            // Animate rotation (Z-axis spin)
            Tween.Rotation(
                transform,
                Quaternion.Euler(startRotation),
                Quaternion.Euler(endRotation),
                _duration,
                0f,
                _rotationCurve,
                Tween.LoopType.None,
                null,
                null,
                true // obey timescale
            );
        }
        
        /// <summary>
        /// Called when animation completes - destroy the GameObject
        /// </summary>
        private void OnAnimationComplete()
        {
            _isAnimating = false;
            
            // Clean up sprite to avoid memory leak
            if (_picture != null && _picture.sprite != null)
            {
                Sprite sprite = _picture.sprite;
                _picture.sprite = null;
                Destroy(sprite.texture);
                Destroy(sprite);
            }
            
            // Destroy the animation GameObject
            Destroy(gameObject);
        }
    }
}