using System.Collections.Generic;
using UnityEngine;
using UnityEngine.InputSystem; 
using Interaction.Conditions;
using Michsky.UI.Reach;

namespace Player
{
    [RequireComponent(typeof(CharacterController))]
    [RequireComponent(typeof(PlayerInput))]
    public class PlayerController : MonoBehaviour
    {
        [Header("Movement Settings")]
        [SerializeField] private float moveSpeed = 5f;
        [SerializeField] private float jumpHeight = 1.2f;
        [SerializeField] private float gravity = -9.81f;
        
        [Header("Look Settings")]
        [SerializeField] private float mouseSensitivity = 1.2f;
        [SerializeField] private Transform camPivot; // 摄像机支架（用于上下看）
        [SerializeField] private float maxLookAngle = 80f; // 抬头低头限制

        [Header("Interaction Settings")]
        [SerializeField] private float interactRange = 3f;
        [SerializeField] private LayerMask interactLayer;
        [SerializeField] private Transform cameraTransform;

        [Header("Interaction Prompt UI")]
        [SerializeField] private bool enableAimPrompt = true;
        [SerializeField] private FeedNotification canInteractNotification;
        [SerializeField] private FeedNotification blockedNotification;
        [SerializeField] private float aimPromptRefreshInterval = 0.05f;
        [SerializeField] private bool blockedUseFailReason = true;

        [Header("References")]
        [SerializeField] private Transform bodyTransform; 

        private CharacterController characterController;
        private PlayerInput playerInput; // 引用 PlayerInput
        private Vector2 moveInput;
        private Vector2 lookInput;
        private float xRotation = 0f;
        private Vector3 playerVelocity;
        private bool isGrounded;
        private System.Action<InputAction.CallbackContext> movePerformedHandler;
        private System.Action<InputAction.CallbackContext> moveCanceledHandler;
        private System.Action<InputAction.CallbackContext> lookPerformedHandler;
        private System.Action<InputAction.CallbackContext> lookCanceledHandler;

        private enum AimPromptState
        {
            None = 0,
            Allowed = 1,
            Blocked = 2
        }

        private AimPromptState aimPromptState;
        private Collider lastAimCollider;
        private string lastBlockedReason;
        private float nextAimPromptTime;
        private string canInteractOriginalText;
        private string blockedOriginalText;

        public void ResetInputState()
        {
            moveInput = Vector2.zero;
            lookInput = Vector2.zero;
        }

        public void SetMouseSensitivity(float value)
        {
            float v = Mathf.Max(0f, value);
            if (Mathf.Approximately(mouseSensitivity, v)) { return; }
            mouseSensitivity = v;
            Debug.Log($"[Player] MouseSensitivity set to {mouseSensitivity}");
        }

        private void Awake()
        {
            characterController = GetComponent<CharacterController>();
            playerInput = GetComponent<PlayerInput>(); // 获取组件
            
            if (cameraTransform == null)
                cameraTransform = GetComponentInChildren<Camera>()?.transform;
            
            if (camPivot == null && cameraTransform != null)
                camPivot = cameraTransform.parent;

            if (bodyTransform == null)
                bodyTransform = transform.Find("Body");
                
            // 锁定鼠标光标
            Cursor.lockState = CursorLockMode.Locked;
            Cursor.visible = false;

            if (canInteractNotification != null) canInteractOriginalText = canInteractNotification.notificationText;
            if (blockedNotification != null) blockedOriginalText = blockedNotification.notificationText;
        }

        private void OnEnable()
        {
            // --- 显式订阅 Input System 事件 ---
            // 这种方式比 SendMessage 更明确，不容易出错
            if (playerInput != null)
            {
                // 确保你的 Action Map 名字正确 (默认通常是 "Player")
                var moveAction = playerInput.actions["Move"];
                if (moveAction != null)
                {
                    if (movePerformedHandler == null) movePerformedHandler = ctx => moveInput = ctx.ReadValue<Vector2>();
                    if (moveCanceledHandler == null) moveCanceledHandler = _ => moveInput = Vector2.zero;
                    moveAction.performed += movePerformedHandler;
                    moveAction.canceled += moveCanceledHandler;
                }

                var lookAction = playerInput.actions["Look"];
                if (lookAction != null)
                {
                    if (lookPerformedHandler == null) lookPerformedHandler = ctx => lookInput = ctx.ReadValue<Vector2>();
                    if (lookCanceledHandler == null) lookCanceledHandler = _ => lookInput = Vector2.zero;
                    lookAction.performed += lookPerformedHandler;
                    lookAction.canceled += lookCanceledHandler;
                }

                var jumpAction = playerInput.actions["Jump"];
                if (jumpAction != null)
                {
                    jumpAction.performed += OnJump;
                }

                var interactAction = playerInput.actions["Interact"];
                if (interactAction != null)
                {
                    interactAction.performed += OnInteract;
                    Debug.Log("<color=green>[Player] Interact Action 绑定成功</color>");
                }
                else
                {
                    Debug.LogError("<color=red>[Player] 找不到名为 'Interact' 的 Action！请检查 Input Actions 文件。</color>");
                }
            }
            else
            {
                Debug.LogError("<color=red>[Player] PlayerInput 组件未找到！</color>");
            }
        }

        private void OnDisable()
        {
            // 记得取消订阅，防止内存泄漏或报错
            if (playerInput != null)
            {
                var moveAction = playerInput.actions["Move"];
                if (moveAction != null)
                {
                    if (movePerformedHandler != null) moveAction.performed -= movePerformedHandler;
                    if (moveCanceledHandler != null) moveAction.canceled -= moveCanceledHandler;
                }

                var lookAction = playerInput.actions["Look"];
                if (lookAction != null)
                {
                    if (lookPerformedHandler != null) lookAction.performed -= lookPerformedHandler;
                    if (lookCanceledHandler != null) lookAction.canceled -= lookCanceledHandler;
                }

                var jumpAction = playerInput.actions["Jump"];
                if (jumpAction != null) jumpAction.performed -= OnJump;

                var interactAction = playerInput.actions["Interact"];
                if (interactAction != null) interactAction.performed -= OnInteract;
            }

            ResetInputState();
        }

        private void Update()
        {
            HandleMovement();
            HandleLook();
            UpdateAimPrompt();
        }

        private void UpdateAimPrompt()
        {
            if (!enableAimPrompt) return;
            if (cameraTransform == null) return;
            if (aimPromptRefreshInterval > 0f && Time.time < nextAimPromptTime) return;

            nextAimPromptTime = aimPromptRefreshInterval > 0f ? Time.time + aimPromptRefreshInterval : Time.time;

            Ray ray = new Ray(cameraTransform.position, cameraTransform.forward);
            if (!Physics.Raycast(ray, out RaycastHit hit, interactRange, interactLayer))
            {
                SetAimPromptState(AimPromptState.None, null, null);
                return;
            }

            var hitCollider = hit.collider;
            bool hasInteractable = false;

            var interactablesOnHit = hitCollider.GetComponents<IInteractable>();
            if (interactablesOnHit != null && interactablesOnHit.Length > 0) hasInteractable = true;
            else
            {
                var interactablesInParents = hitCollider.GetComponentsInParent<IInteractable>();
                if (interactablesInParents != null && interactablesInParents.Length > 0) hasInteractable = true;
            }

            if (!hasInteractable)
            {
                SetAimPromptState(AimPromptState.None, hitCollider, null);
                return;
            }

            bool allowed = true;
            string failReason = null;
            var conditions = hitCollider.GetComponentsInParent<InteractConditionBehaviour>();
            for (int i = 0; i < conditions.Length; i++)
            {
                var condition = conditions[i];
                if (condition == null) continue;

                if (!condition.CanInteract(gameObject, out failReason))
                {
                    allowed = false;
                    break;
                }
            }

            SetAimPromptState(allowed ? AimPromptState.Allowed : AimPromptState.Blocked, hitCollider, failReason);
        }

        private void SetAimPromptState(AimPromptState state, Collider collider, string failReason)
        {
            bool colliderChanged = lastAimCollider != collider;
            bool stateChanged = aimPromptState != state;
            bool reasonChanged = (state == AimPromptState.Blocked) && lastBlockedReason != failReason;

            lastAimCollider = collider;
            lastBlockedReason = failReason;

            if (!colliderChanged && !stateChanged && !reasonChanged) return;

            aimPromptState = state;

            if (state == AimPromptState.Allowed)
            {
                SetNotificationActiveFast(blockedNotification, false);
                if (canInteractNotification != null)
                {
                    canInteractNotification.UpdateUI();
                    SetNotificationActiveFast(canInteractNotification, true);
                }
                return;
            }

            if (state == AimPromptState.Blocked)
            {
                SetNotificationActiveFast(canInteractNotification, false);
                if (blockedNotification != null)
                {
                    if (blockedUseFailReason)
                    {
                        string text = string.IsNullOrWhiteSpace(failReason) ? blockedOriginalText : failReason;
                        if (!string.IsNullOrEmpty(text))
                        {
                            blockedNotification.notificationText = text;
                            blockedNotification.UpdateUI();
                        }
                    }
                    SetNotificationActiveFast(blockedNotification, true);
                }
                return;
            }

            if (canInteractNotification != null)
            {
                if (!string.IsNullOrEmpty(canInteractOriginalText))
                {
                    canInteractNotification.notificationText = canInteractOriginalText;
                    canInteractNotification.UpdateUI();
                }
                SetNotificationActiveFast(canInteractNotification, false);
            }

            if (blockedNotification != null)
            {
                if (!string.IsNullOrEmpty(blockedOriginalText))
                {
                    blockedNotification.notificationText = blockedOriginalText;
                    blockedNotification.UpdateUI();
                }
                SetNotificationActiveFast(blockedNotification, false);
            }
        }

        private static void SetNotificationActiveFast(FeedNotification notification, bool active)
        {
            if (notification == null) return;
            
            // 绕过 ReachUI 内部的协程动画，直接控制 GameObject 显隐
            // 注意：因为我们不再使用 ExpandNotification/MinimizeNotification，
            // 需确保 Animator 已经被移除或禁用，以免残留的动画覆盖我们的显示状态。
            notification.gameObject.SetActive(active);
        }

        private void HandleLook()
        {
            float mouseX = lookInput.x * mouseSensitivity * Time.deltaTime;
            float mouseY = lookInput.y * mouseSensitivity * Time.deltaTime;

            // 1. 左右旋转 (旋转整个角色身体)
            transform.Rotate(Vector3.up * mouseX);

            // 2. 上下旋转 (只旋转摄像机支架)
            if (camPivot != null)
            {
                xRotation -= mouseY;
                xRotation = Mathf.Clamp(xRotation, -maxLookAngle, maxLookAngle);
                camPivot.localRotation = Quaternion.Euler(xRotation, 0f, 0f);
            }
        }

        private void HandleMovement()
        {
            isGrounded = characterController.isGrounded;
            if (isGrounded && playerVelocity.y < 0)
            {
                playerVelocity.y = -2f; 
            }

            // --- 处理移动 ---
            // 直接使用 transform.right/forward，因为身体已经跟随鼠标旋转了
            Vector3 move = transform.right * moveInput.x + transform.forward * moveInput.y;
            
            characterController.Move(move * moveSpeed * Time.deltaTime);

            // --- 处理重力 ---
            playerVelocity.y += gravity * Time.deltaTime;
            characterController.Move(playerVelocity * Time.deltaTime);
        }

        // --- Input System Events ---
        
        // 注意：现在不需要 public void OnMove(...) 这种格式了，因为我们已经在 OnEnable 里手动订阅了
        
        public void OnJump(InputAction.CallbackContext context)
        {
            if (context.performed && isGrounded)
            {
                playerVelocity.y = Mathf.Sqrt(jumpHeight * -2f * gravity);
            }
        }

        public void OnInteract(InputAction.CallbackContext context)
        {
            if (context.performed)
            {
                Debug.Log($"<color=cyan>[Input] 按下了 Interact 键 (F)</color>");
                PerformInteract();
            }
        }

        private void PerformInteract()
        {
            if (cameraTransform == null)
            {
                Debug.LogError("<color=red>[Error] CameraTransform 为空！无法发射射线。</color>");
                return;
            }

            Ray ray = new Ray(cameraTransform.position, cameraTransform.forward);
            Debug.DrawRay(ray.origin, ray.direction * interactRange, Color.red, 2f); // 红色射线停留2秒

            Debug.Log($"<color=yellow>[Raycast] 尝试发射射线... 起点:{ray.origin} 方向:{ray.direction}</color>");

            if (Physics.Raycast(ray, out RaycastHit hit, interactRange, interactLayer))
            {
                Debug.Log($"<color=green>[Hit] 击中了物体: {hit.collider.name}</color> | Layer: {LayerMask.LayerToName(hit.collider.gameObject.layer)}");

                var interactables = new List<IInteractable>(8);
                var unique = new HashSet<IInteractable>();

                var interactablesOnHit = hit.collider.GetComponents<IInteractable>();
                for (int i = 0; i < interactablesOnHit.Length; i++)
                {
                    var it = interactablesOnHit[i];
                    if (it == null) continue;
                    if (unique.Add(it)) interactables.Add(it);
                }

                var interactablesInParents = hit.collider.GetComponentsInParent<IInteractable>();
                for (int i = 0; i < interactablesInParents.Length; i++)
                {
                    var it = interactablesInParents[i];
                    if (it == null) continue;
                    if (unique.Add(it)) interactables.Add(it);
                }

                if (interactables.Count > 0)
                {
                    var conditions = hit.collider.GetComponentsInParent<InteractConditionBehaviour>();
                    for (int i = 0; i < conditions.Length; i++)
                    {
                        var condition = conditions[i];
                        if (condition == null) continue;

                        if (!condition.CanInteract(gameObject, out string failReason))
                        {
                            var failedTriggers = hit.collider.GetComponentsInParent<Core.Triggers.InteractFailedTrigger>();
                            if (failedTriggers == null || failedTriggers.Length == 0)
                            {
                                Debug.LogWarning($"<color=orange>[Interact] 条件失败，但在 '{hit.collider.name}' 及其父级找不到 InteractFailedTrigger</color>");
                            }
                            for (int t = 0; t < failedTriggers.Length; t++)
                            {
                                if (failedTriggers[t] != null) failedTriggers[t].OnFailed(failReason);
                            }

                            if (!string.IsNullOrWhiteSpace(failReason))
                            {
                                Debug.LogWarning($"<color=orange>[Interact] 条件不满足：{failReason}</color>");
                            }
                            else
                            {
                                Debug.LogWarning("<color=orange>[Interact] 条件不满足</color>");
                            }
                            return;
                        }
                    }

                    Debug.Log($"<color=green>[Success] 找到 {interactables.Count} 个 IInteractable，准备依次调用 Interact()</color>");
                    for (int i = 0; i < interactables.Count; i++)
                    {
                        var interactable = interactables[i];
                        if (interactable == null) continue;
                        interactable.Interact();
                    }

                    for (int i = 0; i < conditions.Length; i++)
                    {
                        var condition = conditions[i];
                        if (condition == null) continue;
                        condition.OnInteractSucceeded(gameObject);
                    }
                }
                else
                {
                    Debug.LogWarning($"<color=orange>[Fail] 击中了 {hit.collider.name}，但找不到 IInteractable 脚本 (也没在父物体找到)</color>");
                }
            }
            else
            {
                Debug.Log("<color=grey>[Miss] 射线没有击中任何 Interact Layer 的物体</color>");
            }
        }
    }
}