using System;
using UnityEngine;

namespace Cielonos.MainGame
{
    public partial class RunManager
    {
        /// <summary>
        /// 管理地图节点选择、进入和完成。
        /// 这里负责把 RunMapNode 转换为 RunPhase 与 Zone 加载请求，但不直接处理 CombatRoom 的敌人死亡事件。
        /// </summary>
        public class RunNodeFlowSubmodule : SubmoduleBase<RunManager>
        {
            public RunNodeFlowSubmodule(RunManager owner) : base(owner)
            {
            }

            public void SelectNode(Vector2Int targetPosition)
            {
                if (owner.currentRun == null)
                {
                    Debug.LogWarning("[RunManager] 当前没有进行中的 Run，忽略节点选择。");
                    return;
                }

                if (!owner.CanSelectMapNodes)
                {
                    LogMapSelectionBlocked();
                    return;
                }

                if (targetPosition == owner.currentRun.currentPosition)
                {
                    Debug.Log("[RunManager] 目标即当前位置，忽略。");
                    return;
                }

                if (!IsNodeReachable(targetPosition))
                {
                    Debug.LogWarning(
                        $"[RunManager] 节点 {targetPosition} 不可到达" +
                        "（不在已访问节点的1格范围内）。");
                    return;
                }

                if (!owner.currentRun.mapData.nodes.TryGetValue(targetPosition, out RunMapNode targetNode))
                {
                    Debug.LogError($"[RunManager] 节点 {targetPosition} 在地图数据中不存在。");
                    return;
                }

                owner.currentRun.currentPosition = targetPosition;
                bool isFirstVisit = owner.currentRun.visitedNodes.Add(targetPosition);
                bool isCompleted = owner.currentRun.completedNodes.Contains(targetPosition);

                owner.RaiseNodeSelected(targetPosition);
                owner.RaiseZoneEntered(new ZoneEntryContext(targetPosition, targetNode, isFirstVisit, isCompleted));
                Debug.Log($"[RunManager] 移动到节点 {targetPosition}，类型：{targetNode.nodeType}" +
                          $"，首次进入：{isFirstVisit}，已完成：{isCompleted}");

                CombatManager.AttackAreaSm.DestroyAll();
                EnterNode(targetNode);
            }

            public void CompleteCurrentNode()
            {
                if (owner.currentRun == null) return;

                Vector2Int pos = owner.currentRun.currentPosition;
                if (owner.currentRun.completedNodes.Contains(pos))
                {
                    Debug.Log($"[RunManager] 节点 {pos} 已完成过，跳过重复结算。但检查是否需要切回 MapSelection。");
                    if (owner.currentPhase != RunPhase.MapSelection)
                    {
                        owner.phaseSm.TransitionToPhase(RunPhase.MapSelection);
                    }

                    return;
                }

                if (!owner.currentRun.mapData.nodes.TryGetValue(pos, out RunMapNode node))
                {
                    return;
                }

                owner.currentRun.completedNodes.Add(pos);

                if (RunNodeTypeUtility.ShouldCountAsClearedRoom(node.nodeType))
                {
                    owner.currentRun.roomsCleared++;
                }

                if (RunNodeTypeUtility.IsSingleUseNode(node.nodeType))
                {
                    owner.currentRun.exhaustedNodes.Add(pos);
                }

                owner.RaiseNodeCompleted(node);

                if (owner.currentRun.currentPosition == owner.currentRun.mapData.bossPosition)
                {
                    owner.currentRun.isCompleted = true;
                    Debug.Log("[RunManager] Boss 已击败，Run 通关！");
                    owner.phaseSm.TransitionToPhase(RunPhase.Settlement);
                    owner.RaiseRunEnded(owner.currentRun);
                    return;
                }

                owner.phaseSm.TransitionToPhase(RunPhase.MapSelection);
            }

            private bool IsNodeReachable(Vector2Int targetPosition)
            {
                if (owner.currentRun.visitedNodes.Contains(targetPosition))
                {
                    return true;
                }

                foreach (Vector2Int visitedPos in owner.currentRun.visitedNodes)
                {
                    if (!owner.currentRun.mapData.nodes.TryGetValue(visitedPos, out RunMapNode node))
                    {
                        continue;
                    }

                    if (node.connectedPositions.Contains(targetPosition))
                    {
                        return true;
                    }
                }

                return false;
            }

            private void LogMapSelectionBlocked()
            {
                if (owner.currentRun == null)
                {
                    Debug.LogWarning("[RunManager] 当前没有进行中的 Run，忽略节点选择。");
                    return;
                }

                if (!owner.phaseSm.IsPhaseAllowingNodeSelection())
                {
                    Debug.LogWarning($"[RunManager] 当前阶段为 {owner.currentPhase}，不允许选择节点。");
                    return;
                }

                if (owner.HasPendingCombatRewards)
                {
                    Debug.LogWarning($"[RunManager] 当前仍有 {owner.combatRewardSm.PendingCount} 个 Combat 奖励未领取，不能前往下一个节点。");
                }
            }

            private void EnterNode(RunMapNode node)
            {
                bool isCompleted = owner.currentRun.completedNodes.Contains(owner.currentRun.currentPosition);
                RunPhase targetPhase = isCompleted ? RunPhase.MapSelection : RunNodeTypeUtility.ToRunPhase(node.nodeType);
                bool shouldStartBattleSetup = RunNodeTypeUtility.ShouldStartBattleSetup(node, isCompleted);
                ZoneSetupMode setupMode = shouldStartBattleSetup
                    ? ZoneSetupMode.CombatEncounter
                    : ZoneSetupMode.EnvironmentOnly;

                if (isCompleted)
                {
                    Debug.Log($"[RunManager] 节点 {owner.currentRun.currentPosition} 已完成，跳过 {RunNodeTypeUtility.ToRunPhase(node.nodeType)}，直接进入 MapSelection。");
                }

                if (node.zoneData == null)
                {
                    throw new Exception($"[RunManager] 节点 {owner.currentRun.currentPosition} 没有配置 ZoneData，无法进入对应阶段。");
                }

                owner.phaseSm.TransitionToPhase(RunPhase.Transitioning);
                MapManager.Instance.LoadZone(node.zoneData, onComplete: () =>
                {
                    owner.phaseSm.TransitionToPhase(targetPhase);
                }, setupMode: setupMode);
            }
        }
    }
}