using Unity.Netcode;
using UnityEngine;

namespace Northbound
{
    /// <summary>
    /// Controls object visibility based on fog of war state
    /// Attach to buildings, obstacles, enemies, or any object that should be hidden in fog
    /// </summary>
    public class FogOfWarVisibility : MonoBehaviour
    {
        [Header("Visibility Settings")]
        [Tooltip("Always show this object regardless of fog state (for core, important structures)")]
        public bool alwaysVisible = false;

        [Tooltip("Show this object in explored areas (greyed out) or only when visible")]
        public bool showInExploredAreas = false;

        [Tooltip("Update frequency for checking fog state (seconds)")]
        public float updateInterval = 0.2f;

        [Tooltip("Renderers to show/hide (auto-detected if empty)")]
        public Renderer[] renderers;

        [Header("Extended Visibility")]
        [Tooltip("Enable visibility from farther away based on object height")]
        public bool enableDistantVisibility = true;

        [Tooltip("Base visibility range (additional range beyond player vision)")]
        public float baseVisibilityRange = 10f;

        [Tooltip("Visibility range multiplier per unit of height (default: 2x vision per 1m height)")]
        public float heightVisibilityMultiplier = 2.0f;

        [Tooltip("Minimum height to get extended visibility (meters)")]
        public float minHeightForDistantVisibility = 3.0f;

        [Header("Explored State Visual (Optional)")]
        [Tooltip("Apply grey/desaturated material when in explored state")]
        public bool useExploredMaterial = false;

        [Tooltip("Material to use in explored state (optional)")]
        public Material exploredMaterial;

        private Material[] _originalMaterials;
        private bool _isVisible = false;
        private float _updateTimer;
        private ulong _localPlayerId;
        private bool _isInitialized = false;
        private float _objectHeight = 0f;

        private void Start()
        {
            // Auto-detect renderers if not set
            if (renderers == null || renderers.Length == 0)
            {
                renderers = GetComponentsInChildren<Renderer>();
            }

            if (renderers == null || renderers.Length == 0)
            {
                // Debug.LogWarning($"[FogOfWarVisibility] {gameObject.name}: No renderers found! Component will not work.");
                return;
            }

            // Store original materials for explored state
            if (useExploredMaterial && renderers != null && renderers.Length > 0)
            {
                _originalMaterials = new Material[renderers.Length];
                for (int i = 0; i < renderers.Length; i++)
                {
                    if (renderers[i] != null)
                    {
                        _originalMaterials[i] = renderers[i].sharedMaterial;
                    }
                }
            }

            // Calculate object height for distant visibility
            _objectHeight = CalculateObjectHeight();

            // CRITICAL: Start hidden and stay hidden until fog system confirms visibility
            // Force initial hide - don't use SetVisible because _isVisible defaults to false
            // which would cause early return
            // 단, alwaysVisible이면 항상 보임
            if (alwaysVisible)
            {
                _isVisible = false;
                SetVisible(true);
            }
            else
            {
                _isVisible = true; // Set to true first so SetVisible(false) actually runs
                SetVisible(false);
            }
        }

        /// <summary>
        /// Calculate the height of this object for distant visibility
        /// </summary>
        private float CalculateObjectHeight()
        {
            // Try to get height from Building component
            var building = GetComponent<Building>();
            if (building != null && building.buildingData != null)
            {
                return building.buildingData.height;
            }

            // Fallback: Use renderer bounds
            if (renderers != null && renderers.Length > 0)
            {
                float maxHeight = 0f;
                foreach (var renderer in renderers)
                {
                    if (renderer != null)
                    {
                        maxHeight = Mathf.Max(maxHeight, renderer.bounds.size.y);
                    }
                }
                return maxHeight;
            }

            // Last resort: Use collider bounds
            var collider = GetComponent<Collider>();
            if (collider != null)
            {
                return collider.bounds.size.y;
            }

            return 0f;
        }

        private void Update()
        {
            // Only run on clients, not on dedicated server
            if (NetworkManager.Singleton != null && NetworkManager.Singleton.IsServer && !NetworkManager.Singleton.IsClient)
            {
                // Dedicated server - don't process visibility
                return;
            }

            // Initialize when network is ready
            if (!_isInitialized)
            {
                if (NetworkManager.Singleton != null && NetworkManager.Singleton.IsClient)
                {
                    _localPlayerId = GetLocalPlayerId();
                    if (_localPlayerId == ulong.MaxValue)
                    {
                        // Local player not found yet - stay hidden
                        SetVisible(false);
                        return;
                    }
                    _isInitialized = true;

                    // Force immediate visibility update on initialization
                    UpdateVisibility();
                }
                else
                {
                    // Network not ready - stay hidden
                    SetVisible(false);
                    return;
                }
            }

            _updateTimer += Time.deltaTime;
            if (_updateTimer >= updateInterval)
            {
                _updateTimer = 0f;
                UpdateVisibility();
            }
        }

        /// <summary>
        /// 로컬 플레이어의 실제 ID 가져오기
        /// </summary>
        private ulong GetLocalPlayerId()
        {
            if (NetworkManager.Singleton == null) return ulong.MaxValue;

            // 방법 1: SpawnManager에서 찾기
            NetworkObject localPlayer = null;
            if (NetworkManager.Singleton.SpawnManager != null)
            {
                localPlayer = NetworkManager.Singleton.SpawnManager.GetLocalPlayerObject();
            }

            // 방법 2: LocalClient에서 찾기
            if (localPlayer == null && NetworkManager.Singleton.LocalClient != null)
            {
                localPlayer = NetworkManager.Singleton.LocalClient.PlayerObject;
            }

            // 방법 3: 직접 검색 (IsLocalPlayer인 플레이어 찾기)
            if (localPlayer == null)
            {
                var allPlayers = FindObjectsByType<NetworkPlayerController>(FindObjectsSortMode.None);
                foreach (var player in allPlayers)
                {
                    if (player.IsLocalPlayer)
                    {
                        localPlayer = player.GetComponent<NetworkObject>();
                        break;
                    }
                }
            }

            if (localPlayer == null) return ulong.MaxValue;

            var playerController = localPlayer.GetComponent<NetworkPlayerController>();
            if (playerController == null) return ulong.MaxValue;

            return playerController.OwnerPlayerId;
        }

        private void UpdateVisibility()
        {
            // 항상 보이는 객체는 fog 체크 안함
            if (alwaysVisible)
            {
                SetVisible(true);
                return;
            }

            var fogSystem = FogOfWarSystem.Instance;
            if (fogSystem == null)
            {
                // No fog system - stay hidden for safety
                SetVisible(false);
                return;
            }

            // Wait for fog data to be initialized
            var fogData = fogSystem.GetPlayerFogData(_localPlayerId);
            if (fogData == null)
            {
                // Fog data not ready yet - stay hidden
                SetVisible(false);
                return;
            }

            FogOfWarState fogState = fogSystem.GetVisibilityState(_localPlayerId, transform.position);

            // Check for distant visibility based on height
            bool isDistantVisible = false;
            if (enableDistantVisibility && _objectHeight >= minHeightForDistantVisibility)
            {
                isDistantVisible = CheckDistantVisibility(fogSystem);
            }

            switch (fogState)
            {
                case FogOfWarState.Visible:
                    // Currently visible - show with original materials
                    SetVisible(true);
                    SetExploredVisual(false);
                    break;

                case FogOfWarState.Explored:
                    // Previously seen but not currently visible
                    // BUT: Tall objects can be seen from farther away
                    if (showInExploredAreas || isDistantVisible)
                    {
                        SetVisible(true);
                        SetExploredVisual(true);
                    }
                    else
                    {
                        SetVisible(false);
                    }
                    break;

                case FogOfWarState.Unexplored:
                    // Never seen - hide unless tall enough to see from distance
                    if (isDistantVisible)
                    {
                        SetVisible(true);
                        SetExploredVisual(true); // Show as explored/distant
                    }
                    else
                    {
                        SetVisible(false);
                    }
                    break;

                default:
                    // Unknown state - hide completely
                    SetVisible(false);
                    break;
            }
        }

        /// <summary>
        /// Check if this object should be visible from a distance based on its height
        /// </summary>
        private bool CheckDistantVisibility(FogOfWarSystem fogSystem)
        {
            // Find the closest vision provider (player)
            if (NetworkManager.Singleton == null || !NetworkManager.Singleton.IsClient)
                return false;

            // Get local player object
            var localPlayer = NetworkManager.Singleton.LocalClient?.PlayerObject;
            if (localPlayer == null)
                return false;

            // Calculate distance to player
            float distanceToPlayer = Vector3.Distance(transform.position, localPlayer.transform.position);

            // Calculate extended visibility range based on height
            // Taller objects can be seen from farther away
            // Formula: Base range + (height - minHeight) * multiplier
            float extendedRange = 0f;
            if (_objectHeight >= minHeightForDistantVisibility)
            {
                extendedRange = (_objectHeight - minHeightForDistantVisibility) * heightVisibilityMultiplier;
            }

            // Total range = player vision + base visibility + height bonus
            float totalRange = baseVisibilityRange + extendedRange;

            return distanceToPlayer <= totalRange;
        }

        private void SetVisible(bool visible)
        {
            if (_isVisible == visible) return;

            _isVisible = visible;

            if (renderers == null || renderers.Length == 0)
                return;

            foreach (var renderer in renderers)
            {
                if (renderer != null)
                {
                    renderer.enabled = visible;
                }
            }
        }

        private void SetExploredVisual(bool explored)
        {
            if (!useExploredMaterial || renderers == null || exploredMaterial == null)
                return;

            for (int i = 0; i < renderers.Length; i++)
            {
                if (renderers[i] != null)
                {
                    if (explored)
                    {
                        renderers[i].material = exploredMaterial;
                    }
                    else if (_originalMaterials != null && i < _originalMaterials.Length)
                    {
                        renderers[i].material = _originalMaterials[i];
                    }
                }
            }
        }

        private void OnDrawGizmosSelected()
        {
            // Visualize fog state check position
            Gizmos.color = _isVisible ? Color.green : Color.red;
            Gizmos.DrawWireSphere(transform.position, 0.5f);
        }
    }
}