using System;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AI;
using UnityEngine.EventSystems;
using UnityEngine.InputSystem;

namespace MedievalShopkeeper
{
    /// <summary>
    /// Player Controller designed for a Medieval Shopkeeper game.
    /// Supports PC (Left-Click to Move, Right-Click to Interact) and Mobile (Tap to Move / Tap Interactable to Approach & Interact).
    /// Uses NavMeshAgent for shop navigation and Unity's New Input System.
    /// </summary>
    [RequireComponent(typeof(NavMeshAgent))]
    [SelectionBase]
    public class PlayerController : MonoBehaviour
    {
        [Header("References")]
        [Tooltip("The camera used for raycasting screen clicks. Defaults to Camera.main.")]
        [SerializeField] private Camera playerCamera;

        [Tooltip("NavMeshAgent component. If unassigned, will be retrieved on Awake.")]
        [SerializeField] private NavMeshAgent agent;

        [Tooltip("Optional Animator component for walking and carrying animations.")]
        [SerializeField] private Animator animator;

        [Header("Movement Settings")]
        [Tooltip("Standard walking speed of the shopkeeper.")]
        [SerializeField] private float walkSpeed = 4.0f;

        [Tooltip("Turning speed in degrees per second.")]
        [SerializeField] private float turnSpeed = 1080f;

        [Tooltip("If true, turns on the spot when changing directions sharply instead of making wide circular arcs.")]
        [SerializeField] private bool turnInPlace = true;

        [Tooltip("Turning/angular speed in degrees per second.")]
        [SerializeField] private float agentAngularSpeed = 720f;

        [Tooltip("Acceleration of the agent for crisp starting and stopping.")]
        [SerializeField] private float agentAcceleration = 24f;

        [Tooltip("Speed multiplier applied when carrying stock boxes, crates, or heavy items.")]
        [Range(0.1f, 1f)]
        [SerializeField] private float carrySpeedMultiplier = 0.8f;

        [Tooltip("Distance threshold to consider the destination reached.")]
        [SerializeField] private float destinationThreshold = 0.35f;

        [Tooltip("Shop floor plane Y-level for raycast fallback.")]
        [SerializeField] private float floorYLevel = 0f;

        [Tooltip("Layers representing walkable ground/floor in the shop.")]
        [SerializeField] private LayerMask groundLayers = ~0;

        [Header("Interaction Settings")]
        [Tooltip("Layers representing interactable objects (shelves, stock crates, NPCs, counters).")]
        [SerializeField] private LayerMask interactableLayers = ~0;

        [Tooltip("Default interaction range if the target does not specify one.")]
        [SerializeField] private float defaultInteractionDistance = 2.0f;

        [Tooltip("On mobile / touch: tapping an interactable automatically moves to it and interacts.")]
        [SerializeField] private bool smartTouchInteraction = true;

        [Tooltip("On PC: allow left-click on an interactable to also trigger interaction.")]
        [SerializeField] private bool leftClickAlsoInteracts = false;

        [Header("Shopkeeper Carry System")]
        [Tooltip("Transform socket (e.g. hands or chest) where carried items, boxes, or crates will be attached.")]
        [SerializeField] private Transform carrySocket;

        [Header("Optional Input Actions (New Input System)")]
        [Tooltip("Optional: Action for movement click/tap. If unassigned, defaults to Mouse Left-Click / Touch.")]
        [SerializeField] private InputActionReference moveAction;

        [Tooltip("Optional: Action for interaction click. If unassigned, defaults to Mouse Right-Click.")]
        [SerializeField] private InputActionReference interactAction;

        [Tooltip("Optional: Action for pointer position. If unassigned, reads Mouse/Touch position.")]
        [SerializeField] private InputActionReference pointerPositionAction;

        [Header("Visual Feedback (Optional)")]
        [Tooltip("Optional prefab instantiated or moved to show the click/destination point.")]
        [SerializeField] private GameObject destinationMarkerPrefab;

        [Header("Debug")]
        [Tooltip("Output detailed logs comparing clicked destination vs NavMesh destination.")]
        [SerializeField] private bool enableDebugLogs = true;

        [Header("Animation Parameters")]
        [SerializeField] private string speedAnimParam = "Speed";
        [SerializeField] private string isMovingAnimParam = "IsMoving";
        [SerializeField] private string isCarryingAnimParam = "IsCarrying";

        // Runtime state
        private IInteractable pendingTarget;
        private IInteractable currentHovered;
        private GameObject destinationMarkerInstance;
        private GameObject currentCarriedItem;
        private Vector3 lastClickedDestination;
        private Vector3 lastNavMeshDestination;
        private bool hasActiveMoveCommand;
        private int speedHash;
        private int isMovingHash;
        private int isCarryingHash;

        // Public properties
        public NavMeshAgent Agent => agent;
        public IInteractable PendingTarget => pendingTarget;
        public IInteractable CurrentHovered => currentHovered;
        public GameObject CurrentCarriedItem => currentCarriedItem;
        public bool IsCarryingItem => currentCarriedItem != null;
        public Vector3 LastClickedDestination => lastClickedDestination;
        public Vector3 LastNavMeshDestination => lastNavMeshDestination;

        // Events
        public event Action<Vector3> OnDestinationSet;
        public event Action<IInteractable> OnInteractionTargetSet;
        public event Action<IInteractable> OnInteracted;
        public event Action<IInteractable> OnHoverChanged;
        public event Action<GameObject> OnItemPickedUp;
        public event Action<GameObject> OnItemDropped;

        private void Awake()
        {
            if (agent == null)
            {
                agent = GetComponent<NavMeshAgent>();
            }

            FindCamera();

            // Ensure the camera is statically positioned overhead with TopDownCamera
            if (playerCamera != null)
            {
                TopDownCamera topDownCam = playerCamera.GetComponent<TopDownCamera>();
                if (topDownCam == null)
                {
                    topDownCam = playerCamera.gameObject.AddComponent<TopDownCamera>();
                }
                topDownCam.ApplyCameraTransform();
            }

            if (animator == null)
            {
                animator = GetComponentInChildren<Animator>();
            }

            if (animator != null)
            {
                animator.applyRootMotion = false; // Prevent animations from fighting NavMesh movement
            }

            // Check for offset visual models which cause orbiting
            foreach (var r in GetComponentsInChildren<Renderer>())
            {
                Vector3 localPos = r.transform.localPosition;
                localPos.y = 0; // Ignore vertical offset
                if (localPos.sqrMagnitude > 0.25f) // If offset by more than 0.5m on X/Z
                {
                    Debug.LogWarning($"[PlayerController] WARNING: Visual model '{r.gameObject.name}' is offset from the Player center by {localPos}. This will cause the character to orbit around the pivot point instead of rotating in place! Please center the model in the prefab.");
                }
            }

            // Configure agent for responsive movement without circular orbiting
            agent.speed = walkSpeed;
            agent.angularSpeed = agentAngularSpeed;
            agent.acceleration = agentAcceleration;
            agent.autoBraking = true;
            agent.stoppingDistance = destinationThreshold;
            agent.updateRotation = false; // We handle rotation to eliminate wide circular loops

            // Cache animation hashes
            speedHash = Animator.StringToHash(speedAnimParam);
            isMovingHash = Animator.StringToHash(isMovingAnimParam);
            isCarryingHash = Animator.StringToHash(isCarryingAnimParam);

            // Instantiate destination marker or create default click disc
            if (destinationMarkerPrefab != null)
            {
                destinationMarkerInstance = Instantiate(destinationMarkerPrefab);
                foreach (var col in destinationMarkerInstance.GetComponentsInChildren<Collider>())
                {
                    col.enabled = false;
                }
                destinationMarkerInstance.SetActive(false);
            }
            else
            {
                destinationMarkerInstance = GameObject.CreatePrimitive(PrimitiveType.Cylinder);
                destinationMarkerInstance.name = "ClickDestinationMarker";
                destinationMarkerInstance.transform.localScale = new Vector3(0.5f, 0.01f, 0.5f);
                var col = destinationMarkerInstance.GetComponent<Collider>();
                if (col != null) Destroy(col);
                var rend = destinationMarkerInstance.GetComponent<Renderer>();
                if (rend != null)
                {
                    rend.material.color = new Color(0f, 0.85f, 1f, 0.8f);
                }
                destinationMarkerInstance.SetActive(false);
            }
        }

        private void Start()
        {
            // Ensure the agent is cleanly snapped onto the NavMesh if placed slightly above or below
            if (!agent.isOnNavMesh)
            {
                if (NavMesh.SamplePosition(transform.position, out NavMeshHit navHit, 5.0f, NavMesh.AllAreas))
                {
                    agent.Warp(navHit.position);
                    if (enableDebugLogs)
                    {
                        Debug.Log($"[PlayerController] Agent snapped to NavMesh at: {navHit.position}");
                    }
                }
                else
                {
                    Debug.LogWarning("[PlayerController] Player is not placed on a valid NavMesh! Please ensure the floor has a baked NavMesh.", this);
                }
            }
        }

        private void OnEnable()
        {
            moveAction?.action?.Enable();
            interactAction?.action?.Enable();
            pointerPositionAction?.action?.Enable();
        }

        private void OnDisable()
        {
            moveAction?.action?.Disable();
            interactAction?.action?.Disable();
            pointerPositionAction?.action?.Disable();

            if (currentHovered != null)
            {
                currentHovered.OnHoverExit(this);
                currentHovered = null;
            }
        }

        private void Update()
        {
            // Suspend normal player interaction and movement if building mode is active
            if (BuildManager.Instance != null && BuildManager.Instance.IsBuilding)
            {
                ClearHover(); // Remove UI prompts
                return; // Let BuildManager handle input
            }

            HandleHover();
            HandleInput();
            HandleDestinationArrival();
            HandlePendingInteraction();
            UpdateRotation();
            UpdateAnimation();
        }

        private void FindCamera()
        {
            if (playerCamera == null)
            {
                playerCamera = Camera.main;
                if (playerCamera == null)
                {
                    playerCamera = FindAnyObjectByType<Camera>();
                }
            }
        }

        #region Input Handling

        private void HandleInput()
        {
            Vector2 screenPos = GetPointerPosition();

            // Ignore input if pointer is over UI elements
            if (IsPointerOverUI(screenPos))
            {
                if (WasMovePressed() || WasInteractPressed())
                {
                    if (enableDebugLogs)
                    {
                        Debug.LogWarning($"[PlayerController] Click at screenPos {screenPos} was BLOCKED by UI.");
                    }
                }
                return;
            }

            bool isTouchDevice = IsTouchscreenActive();

            // 1. Primary input (Left Click on PC / Screen Tap on Mobile)
            if (WasMovePressed())
            {
                if (enableDebugLogs)
                {
                    Debug.Log($"<color=#FFFF00>[PlayerController] CLICK DETECTED</color> at screen: {screenPos}");
                }
                if (isTouchDevice && smartTouchInteraction)
                {
                    if (TryRaycastInteractable(screenPos, out IInteractable touchedInteractable))
                    {
                        CommandInteract(touchedInteractable);
                        return;
                    }
                }
                else if (leftClickAlsoInteracts)
                {
                    if (TryRaycastInteractable(screenPos, out IInteractable clickedInteractable))
                    {
                        CommandInteract(clickedInteractable);
                        return;
                    }
                }

                // Move to ground point
                if (TryRaycastGround(screenPos, out Vector3 groundPoint))
                {
                    CommandMove(groundPoint);
                }
                else
                {
                    if (enableDebugLogs)
                    {
                        Debug.LogWarning($"[PlayerController] Left Click at screenPos {screenPos} did NOT hit any ground or NavMesh.");
                    }
                }
            }

            // 2. Secondary input (Right Click on PC)
            if (WasInteractPressed())
            {
                if (TryRaycastInteractable(screenPos, out IInteractable interactable))
                {
                    CommandInteract(interactable);
                }
                else
                {
                    if (enableDebugLogs)
                    {
                        Debug.Log($"[PlayerController] Right Click at screenPos {screenPos} did NOT hit any IInteractable.");
                    }
                }
            }
        }

        private Vector2 GetPointerPosition()
        {
            if (pointerPositionAction != null && pointerPositionAction.action != null && pointerPositionAction.action.enabled)
            {
                return pointerPositionAction.action.ReadValue<Vector2>();
            }

            if (Touchscreen.current != null && Touchscreen.current.primaryTouch.press.isPressed)
            {
                return Touchscreen.current.primaryTouch.position.ReadValue();
            }

            if (Mouse.current != null)
            {
                return Mouse.current.position.ReadValue();
            }

            if (Pointer.current != null)
            {
                return Pointer.current.position.ReadValue();
            }

            return Vector2.zero;
        }

        private bool WasMovePressed()
        {
            if (moveAction != null && moveAction.action != null)
            {
                return moveAction.action.WasPressedThisFrame();
            }

            if (Touchscreen.current != null && Touchscreen.current.primaryTouch.press.wasPressedThisFrame)
            {
                return true;
            }

            if (Mouse.current != null && Mouse.current.leftButton.wasPressedThisFrame)
            {
                return true;
            }

            return false;
        }

        private bool WasInteractPressed()
        {
            if (interactAction != null && interactAction.action != null)
            {
                return interactAction.action.WasPressedThisFrame();
            }

            if (Mouse.current != null && Mouse.current.rightButton.wasPressedThisFrame)
            {
                return true;
            }

            return false;
        }

        private bool IsTouchscreenActive()
        {
            return Touchscreen.current != null && Touchscreen.current.primaryTouch.press.isPressed;
        }

        private bool IsPointerOverUI(Vector2 screenPosition)
        {
            if (EventSystem.current == null) return false;

            if (EventSystem.current.IsPointerOverGameObject()) return true;

            if (Touchscreen.current != null && Touchscreen.current.primaryTouch.press.isPressed)
            {
                int touchId = Touchscreen.current.primaryTouch.touchId.ReadValue();
                if (EventSystem.current.IsPointerOverGameObject(touchId)) return true;
            }

            PointerEventData eventData = new PointerEventData(EventSystem.current)
            {
                position = screenPosition
            };
            var results = new List<RaycastResult>();
            EventSystem.current.RaycastAll(eventData, results);
            return results.Count > 0;
        }

        #endregion

        #region Raycasting

        private bool TryRaycastGround(Vector2 screenPosition, out Vector3 hitPoint)
        {
            hitPoint = Vector3.zero;
            FindCamera();
            if (playerCamera == null) return false;

            Ray ray = playerCamera.ScreenPointToRay(screenPosition);

            // 1. Raycast against physics colliders, excluding the player character
            RaycastHit[] hits = Physics.RaycastAll(ray, 300f, groundLayers, QueryTriggerInteraction.Ignore);
            if (hits.Length > 0)
            {
                Array.Sort(hits, (a, b) => a.distance.CompareTo(b.distance));

                foreach (var hit in hits)
                {
                    if (hit.collider.transform.root == transform.root) continue;

                    // Sample onto NavMesh
                    if (NavMesh.SamplePosition(hit.point, out NavMeshHit navHit, 3.0f, NavMesh.AllAreas))
                    {
                        hitPoint = navHit.position;
                        return true;
                    }

                    hitPoint = hit.point;
                    return true;
                }
            }

            // 2. Mathematical Plane Fallback: If no collider hit, intersect with shop floor Y plane
            Plane floorPlane = new Plane(Vector3.up, new Vector3(0f, floorYLevel, 0f));
            if (floorPlane.Raycast(ray, out float enterDist))
            {
                Vector3 planePoint = ray.GetPoint(enterDist);
                if (NavMesh.SamplePosition(planePoint, out NavMeshHit navHit, 5.0f, NavMesh.AllAreas))
                {
                    hitPoint = navHit.position;
                    return true;
                }

                hitPoint = planePoint;
                return true;
            }

            return false;
        }

        private bool TryRaycastInteractable(Vector2 screenPosition, out IInteractable interactable)
        {
            interactable = null;
            FindCamera();
            if (playerCamera == null) return false;

            Ray ray = playerCamera.ScreenPointToRay(screenPosition);
            RaycastHit[] hits = Physics.RaycastAll(ray, 300f, interactableLayers, QueryTriggerInteraction.Collide);

            if (hits.Length > 0)
            {
                Array.Sort(hits, (a, b) => a.distance.CompareTo(b.distance));

                foreach (var hit in hits)
                {
                    if (hit.collider.transform.root == transform.root) continue;

                    var found = hit.collider.GetComponentInParent<IInteractable>();
                    if (found != null && found.CanInteract(this))
                    {
                        interactable = found;
                        return true;
                    }
                }
            }

            return false;
        }

        #endregion

        #region Movement & Interaction Execution

        /// <summary>
        /// Commands the shopkeeper to walk to a position on the floor, canceling any active interaction target.
        /// </summary>
        public void CommandMove(Vector3 destination)
        {
            ClearPendingTarget();

            if (!agent.isOnNavMesh)
            {
                if (NavMesh.SamplePosition(transform.position, out NavMeshHit navHit, 5.0f, NavMesh.AllAreas))
                {
                    agent.Warp(navHit.position);
                }
                else
                {
                    Debug.LogWarning("[PlayerController] Cannot move: Agent is not on NavMesh!", this);
                    return;
                }
            }

            lastClickedDestination = destination;
            agent.stoppingDistance = destinationThreshold;
            agent.isStopped = false;
            agent.velocity = Vector3.zero; // Kill residual forward momentum to prevent circular turn arcs
            bool setSuccess = agent.SetDestination(destination);
            lastNavMeshDestination = agent.destination;
            hasActiveMoveCommand = true;

            if (enableDebugLogs)
            {
                float dist = Vector3.Distance(transform.position, destination);
                Debug.Log($"<color=#00FF88><b>[PlayerController] CLICKED: {destination} --> NAVMESH: {agent.destination}</b></color> (Player at {transform.position}, Dist: {dist:F2}m, Success: {setSuccess}, PathStatus: {agent.pathStatus})");
            }

            ShowDestinationMarker(destination);
            OnDestinationSet?.Invoke(destination);
        }

        /// <summary>
        /// Commands the shopkeeper to approach an interactable (shelf, crate, NPC) and interact upon arrival.
        /// If already within range, interacts immediately.
        /// </summary>
        public void CommandInteract(IInteractable target)
        {
            if (target == null || !target.CanInteract(this)) return;

            float distance = GetDistanceToInteractable(target);
            float interactionDistance = target.InteractionDistance > 0 ? target.InteractionDistance : defaultInteractionDistance;

            if (enableDebugLogs)
            {
                Debug.Log($"<color=#FFD700><b>[PlayerController] INTERACT COMMAND:</b></color> Target: '{target.InteractionPrompt}' at {target.InteractionTransform.position} | Current Distance: {distance:F2}m (Allowed: {interactionDistance:F2}m)");
            }

            if (distance <= interactionDistance)
            {
                ClearPendingTarget();
                agent.ResetPath();
                agent.velocity = Vector3.zero;
                FaceTarget(target.InteractionTransform.position);
                ExecuteInteraction(target);
            }
            else
            {
                pendingTarget = target;
                hasActiveMoveCommand = false;
                lastClickedDestination = target.InteractionTransform.position;
                agent.stoppingDistance = Mathf.Max(0.5f, interactionDistance * 0.85f);
                agent.isStopped = false;
                agent.SetDestination(target.InteractionTransform.position);
                lastNavMeshDestination = agent.destination;

                ShowDestinationMarker(target.InteractionTransform.position);
                OnInteractionTargetSet?.Invoke(target);
            }
        }

        /// <summary>
        /// Handles stopping cleanly when reaching ground move destinations to prevent orbiting/circling.
        /// </summary>
        private void HandleDestinationArrival()
        {
            if (pendingTarget != null) return;
            if (!hasActiveMoveCommand) return;

            if (!agent.pathPending && agent.hasPath)
            {
                Vector3 flatPos = new Vector3(transform.position.x, 0, transform.position.z);
                Vector3 flatDest = new Vector3(agent.destination.x, 0, agent.destination.z);
                float flatDist = Vector3.Distance(flatPos, flatDest);

                // Normal arrival: within stopping distance or remaining distance
                if (flatDist <= agent.stoppingDistance || agent.remainingDistance <= agent.stoppingDistance)
                {
                    if (enableDebugLogs)
                    {
                        Debug.Log($"<color=#00D4FF><b>[PlayerController] ARRIVED AT DESTINATION:</b></color> Position: {transform.position} (Dist: {flatDist:F2}m)");
                    }

                    hasActiveMoveCommand = false;
                    agent.ResetPath();
                    agent.velocity = Vector3.zero;
                    HideDestinationMarker();
                }
                // Anti-orbiting safeguard: if agent is close and moving away from destination
                else if (flatDist < 0.8f && Vector3.Dot(agent.velocity.normalized, (flatDest - flatPos).normalized) < 0f)
                {
                    if (enableDebugLogs)
                    {
                        Debug.Log($"<color=#FFAA00><b>[PlayerController] OVERSHOOT PREVENTED (STOPPED):</b></color> Position: {transform.position} (Dist: {flatDist:F2}m)");
                    }

                    hasActiveMoveCommand = false;
                    agent.ResetPath();
                    agent.velocity = Vector3.zero;
                    HideDestinationMarker();
                }
            }
        }

        private void HandlePendingInteraction()
        {
            if (pendingTarget == null) return;

            if (!pendingTarget.CanInteract(this))
            {
                ClearPendingTarget();
                return;
            }

            float interactionDistance = pendingTarget.InteractionDistance > 0 ? pendingTarget.InteractionDistance : defaultInteractionDistance;
            float distance = GetDistanceToInteractable(pendingTarget);

            if (distance <= interactionDistance || (!agent.pathPending && agent.remainingDistance <= agent.stoppingDistance))
            {
                IInteractable targetToInteract = pendingTarget;
                ClearPendingTarget();

                agent.ResetPath();
                agent.velocity = Vector3.zero;
                FaceTarget(targetToInteract.InteractionTransform.position);
                ExecuteInteraction(targetToInteract);
            }
        }

        private void ExecuteInteraction(IInteractable target)
        {
            HideDestinationMarker();
            target.Interact(this);
            OnInteracted?.Invoke(target);
        }

        public void ClearPendingTarget()
        {
            pendingTarget = null;
        }

        private float GetDistanceToInteractable(IInteractable target)
        {
            Vector3 targetPos = target.InteractionTransform.position;
            Vector3 playerPos = transform.position;
            targetPos.y = playerPos.y;
            return Vector3.Distance(playerPos, targetPos);
        }

        private void UpdateRotation()
        {
            if (agent == null) return;

            Vector3 targetDirection = Vector3.zero;

            if (pendingTarget != null)
            {
                targetDirection = pendingTarget.InteractionTransform.position - transform.position;
            }
            else if (hasActiveMoveCommand && agent.hasPath)
            {
                targetDirection = agent.steeringTarget - transform.position;
            }

            targetDirection.y = 0;

            if (targetDirection.sqrMagnitude > 0.001f)
            {
                Quaternion targetRot = Quaternion.LookRotation(targetDirection.normalized);
                float angleDiff = Quaternion.Angle(transform.rotation, targetRot);

                // Strict Turn-in-place: if angle is large, stop all movement until facing the target
                if (turnInPlace && angleDiff > 10f)
                {
                    transform.rotation = Quaternion.RotateTowards(transform.rotation, targetRot, turnSpeed * Time.deltaTime);
                    agent.velocity = Vector3.zero; // Completely halt forward momentum while turning!
                    agent.speed = 0f;
                }
                else
                {
                    transform.rotation = Quaternion.RotateTowards(transform.rotation, targetRot, turnSpeed * Time.deltaTime);
                    float baseSpeed = IsCarryingItem ? (walkSpeed * carrySpeedMultiplier) : walkSpeed;
                    agent.speed = baseSpeed;
                }
            }
        }

        private void FaceTarget(Vector3 targetPosition)
        {
            Vector3 direction = (targetPosition - transform.position);
            direction.y = 0;
            if (direction.sqrMagnitude > 0.001f)
            {
                transform.rotation = Quaternion.LookRotation(direction);
            }
        }

        #endregion

        #region Hover Handling

        private void HandleHover()
        {
            if (Mouse.current == null && Pointer.current == null) return;

            Vector2 screenPos = GetPointerPosition();
            if (IsPointerOverUI(screenPos))
            {
                ClearHover();
                return;
            }

            if (TryRaycastInteractable(screenPos, out IInteractable hitInteractable) && hitInteractable.CanInteract(this))
            {
                if (currentHovered != hitInteractable)
                {
                    ClearHover();
                    currentHovered = hitInteractable;
                    currentHovered.OnHoverEnter(this);
                    OnHoverChanged?.Invoke(currentHovered);
                }
            }
            else
            {
                ClearHover();
            }
        }

        private void ClearHover()
        {
            if (currentHovered != null)
            {
                currentHovered.OnHoverExit(this);
                currentHovered = null;
                OnHoverChanged?.Invoke(null);
            }
        }

        #endregion

        #region Shopkeeper Carry System

        /// <summary>
        /// Attaches an item, delivery crate, or stock box into the shopkeeper's carry socket.
        /// </summary>
        public bool CarryItem(GameObject item)
        {
            if (item == null || IsCarryingItem) return false;

            currentCarriedItem = item;

            Transform targetParent = carrySocket != null ? carrySocket : transform;
            item.transform.SetParent(targetParent);
            item.transform.localPosition = Vector3.zero;
            item.transform.localRotation = Quaternion.identity;

            if (item.TryGetComponent(out Rigidbody rb))
            {
                rb.isKinematic = true;
            }

            if (item.TryGetComponent(out Collider col))
            {
                col.enabled = false;
            }

            UpdateMovementSpeed();
            OnItemPickedUp?.Invoke(item);
            return true;
        }

        /// <summary>
        /// Drops the currently carried item onto the ground in front of the player.
        /// </summary>
        public GameObject DropCarriedItem(Vector3? dropPosition = null)
        {
            if (!IsCarryingItem) return null;

            GameObject dropped = currentCarriedItem;
            currentCarriedItem = null;

            dropped.transform.SetParent(null);
            Vector3 targetDrop = dropPosition ?? (transform.position + transform.forward * 0.8f + Vector3.up * 0.2f);
            dropped.transform.position = targetDrop;

            if (dropped.TryGetComponent(out Collider col))
            {
                col.enabled = true;
            }

            if (dropped.TryGetComponent(out Rigidbody rb))
            {
                rb.isKinematic = false;
            }

            UpdateMovementSpeed();
            OnItemDropped?.Invoke(dropped);
            return dropped;
        }

        /// <summary>
        /// Removes the carried item reference without placing it in the world (e.g. placed onto a shelf).
        /// </summary>
        public void ClearCarriedItem()
        {
            currentCarriedItem = null;
            UpdateMovementSpeed();
        }

        private void UpdateMovementSpeed()
        {
            float speed = walkSpeed;
            if (IsCarryingItem)
            {
                speed *= carrySpeedMultiplier;
            }
            agent.speed = speed;
        }

        #endregion

        #region Visuals & Animation

        private void ShowDestinationMarker(Vector3 position)
        {
            if (destinationMarkerInstance != null)
            {
                destinationMarkerInstance.transform.position = position + Vector3.up * 0.05f;
                destinationMarkerInstance.SetActive(true);
            }
        }

        private void HideDestinationMarker()
        {
            if (destinationMarkerInstance != null)
            {
                destinationMarkerInstance.SetActive(false);
            }
        }

        private void UpdateAnimation()
        {
            if (animator == null) return;

            float currentSpeed = agent.velocity.magnitude;
            bool isMoving = agent.velocity.sqrMagnitude > 0.05f && !agent.isStopped && agent.hasPath;

            animator.SetFloat(speedHash, currentSpeed);
            animator.SetBool(isMovingHash, isMoving);
            animator.SetBool(isCarryingHash, IsCarryingItem);
        }

        #endregion

        #region Editor Gizmos

        private void OnDrawGizmos()
        {
            // Draw Clicked Point in bright RED
            if (lastClickedDestination != Vector3.zero)
            {
                Gizmos.color = Color.red;
                Gizmos.DrawSphere(lastClickedDestination, 0.25f);
                Gizmos.DrawLine(transform.position, lastClickedDestination);
            }

            // Draw NavMesh Agent Destination in bright GREEN
            if (agent != null && (hasActiveMoveCommand || agent.hasPath))
            {
                Gizmos.color = Color.green;
                Gizmos.DrawWireSphere(agent.destination, agent.stoppingDistance);
                Gizmos.DrawLine(transform.position, agent.destination);
            }
        }

        private void OnDrawGizmosSelected()
        {
            if (agent != null && agent.hasPath)
            {
                Gizmos.color = Color.green;
                Vector3 prev = transform.position;
                foreach (Vector3 corner in agent.path.corners)
                {
                    Gizmos.DrawLine(prev, corner);
                    Gizmos.DrawSphere(corner, 0.15f);
                    prev = corner;
                }
            }

            if (pendingTarget != null && pendingTarget.InteractionTransform != null)
            {
                Gizmos.color = Color.cyan;
                Gizmos.DrawLine(transform.position, pendingTarget.InteractionTransform.position);
                Gizmos.DrawWireSphere(pendingTarget.InteractionTransform.position, pendingTarget.InteractionDistance);
            }

            if (carrySocket != null)
            {
                Gizmos.color = Color.magenta;
                Gizmos.DrawWireCube(carrySocket.position, Vector3.one * 0.2f);
            }
        }

        #endregion
    }
}