using System;

using Colosseum.Abnormalities;
using Colosseum.AI;
using Colosseum.Combat;
using Colosseum.Enemy;
using Colosseum.Player;
using Colosseum.Skills;

using Unity.Behavior;
using Unity.Properties;
using UnityEngine;

using Action = Unity.Behavior.Action;

/// <summary>
/// 보스 공통 패턴 실행용 Behavior Action 기반 클래스입니다.
/// </summary>
[Serializable, GeneratePropertyBag]
public abstract partial class BossPatternActionBase : Action
{
    [SerializeReference]
    public BlackboardVariable<GameObject> Target;

    protected BossEnemy bossEnemy;
    protected EnemyBase enemyBase;
    protected SkillController skillController;
    protected BossCombatBehaviorContext combatBehaviorContext;
    protected UnityEngine.AI.NavMeshAgent navMeshAgent;
    protected AbnormalityManager abnormalityManager;

    private BossPatternData activePattern;
    private GameObject activeTarget;
    private int currentStepIndex;
    private bool isWaiting;
    private float waitEndTime;

    private bool isChargeWaiting;
    private float chargeEndTime;
    private float chargeAccumulatedDamage;
    private float chargeRequiredDamage;
    private ChargeStepData activeChargeData;
    private bool chargeTelegraphApplied;

    /// <summary>
    /// 액션 시작 시 실제로 실행할 패턴과 대상을 결정합니다.
    /// </summary>
    protected abstract bool TryResolvePattern(out BossPatternData pattern, out GameObject target);

    protected override Status OnStart()
    {
        ResolveReferences();
        ClearRuntimeState();

        if (!IsReady())
            return Status.Failure;

        if (combatBehaviorContext.IsBehaviorSuppressed)
        {
            StopMovement();
            return Status.Failure;
        }

        if (bossEnemy.IsDead || bossEnemy.IsTransitioning)
            return Status.Failure;

        if (skillController.IsPlayingAnimation)
            return Status.Failure;

        if (!TryResolvePattern(out BossPatternData pattern, out GameObject target))
            return Status.Failure;

        activePattern = pattern;
        activeTarget = target;

        if (Target != null)
            Target.Value = target;

        StopMovement();
        return ExecuteCurrentStep();
    }

    protected override Status OnUpdate()
    {
        if (!IsReady() || activePattern == null)
            return Status.Failure;

        if (combatBehaviorContext.IsBehaviorSuppressed)
        {
            StopMovement();
            return Status.Failure;
        }

        if (bossEnemy.IsDead || bossEnemy.IsTransitioning)
            return Status.Failure;

        if (isChargeWaiting)
        {
            if (chargeAccumulatedDamage >= chargeRequiredDamage)
            {
                EndChargeWait(broken: true);
                skillController?.CancelSkill(SkillCancelReason.Interrupt);
                LogDebug($"충전 차단 성공: 누적 {chargeAccumulatedDamage:F1} / 필요 {chargeRequiredDamage:F1}");
                CombatBalanceTracker.RecordBossEvent("집행 개시 차단 성공");
                return Status.Failure;
            }

            if (Time.time < chargeEndTime)
                return Status.Running;

            EndChargeWait(broken: false);
        }
        else if (isWaiting)
        {
            if (Time.time < waitEndTime)
                return Status.Running;

            isWaiting = false;
        }
        else if (skillController.IsPlayingAnimation)
        {
            return Status.Running;
        }

        currentStepIndex++;
        if (currentStepIndex >= activePattern.Steps.Count)
        {
            UsePatternAction.MarkPatternUsed(GameObject, activePattern);
            return Status.Success;
        }

        return ExecuteCurrentStep();
    }

    protected override void OnEnd()
    {
        ClearRuntimeState();
    }

    protected virtual GameObject ResolveStepTarget(GameObject fallbackTarget)
    {
        return fallbackTarget;
    }

    protected GameObject FindNearestLivingPlayer()
    {
        PlayerNetworkController[] players = UnityEngine.Object.FindObjectsByType<PlayerNetworkController>(FindObjectsSortMode.None);
        GameObject nearestTarget = null;
        float nearestDistance = float.MaxValue;
        float maxDistance = enemyBase != null && enemyBase.Data != null ? enemyBase.Data.AggroRange : Mathf.Infinity;

        for (int i = 0; i < players.Length; i++)
        {
            PlayerNetworkController player = players[i];
            if (player == null || player.IsDead || !player.gameObject.activeInHierarchy)
                continue;

            GameObject candidate = player.gameObject;

            float distance = Vector3.Distance(GameObject.transform.position, candidate.transform.position);
            if (distance > maxDistance || distance >= nearestDistance)
                continue;

            nearestDistance = distance;
            nearestTarget = candidate;
        }

        return nearestTarget;
    }

    protected GameObject ResolvePrimaryTarget()
    {
        GameObject highestThreatTarget = enemyBase != null
            ? enemyBase.GetHighestThreatTarget(Target?.Value, null, enemyBase.Data != null ? enemyBase.Data.AggroRange : Mathf.Infinity)
            : null;

        GameObject target = highestThreatTarget != null ? highestThreatTarget : FindNearestLivingPlayer();
        if (Target != null)
            Target.Value = target;

        return target;
    }

    protected bool IsValidHostileTarget(GameObject candidate)
    {
        if (candidate == null || !candidate.activeInHierarchy)
            return false;

        // 보스는 항상 적 팀이므로, 플레이어만 적대 대상으로 간주
        if (candidate.GetComponent<PlayerNetworkController>() == null)
            return false;

        IDamageable damageable = candidate.GetComponent<IDamageable>();
        return damageable == null || !damageable.IsDead;
    }

    protected void StopMovement()
    {
        if (navMeshAgent == null || !navMeshAgent.enabled)
            return;

        navMeshAgent.isStopped = true;
        navMeshAgent.ResetPath();
    }

    protected void LogDebug(string message)
    {
        combatBehaviorContext?.LogDebug(GetType().Name, message);
    }

    private Status ExecuteCurrentStep()
    {
        if (activePattern == null || currentStepIndex < 0 || currentStepIndex >= activePattern.Steps.Count)
            return Status.Failure;

        PatternStep step = activePattern.Steps[currentStepIndex];
        if (step.Type == PatternStepType.Wait)
        {
            isWaiting = true;
            waitEndTime = Time.time + step.Duration;
            return Status.Running;
        }

        if (step.Type == PatternStepType.ChargeWait)
        {
            StartChargeWait(step);
            return Status.Running;
        }

        if (step.Skill == null)
        {
            Debug.LogWarning($"[{GetType().Name}] 스킬이 비어 있는 패턴 스텝입니다: {activePattern.PatternName} / Step={currentStepIndex}");
            return Status.Failure;
        }

        GameObject skillTarget = activeTarget;
        if (step.Skill.JumpToTarget)
        {
            skillTarget = ResolveStepTarget(activeTarget);
            if (skillTarget == null)
            {
                if (activePattern != null && activePattern.SkipJumpStepOnNoTarget)
                {
                    UsePatternAction.MarkPatternUsed(GameObject, activePattern);
                    LogDebug($"점프 대상 없음, 조합 패턴 조기 종료: {activePattern.PatternName}");
                    return Status.Success;
                }

                LogDebug($"점프 타겟을 찾지 못해 실패: {activePattern.PatternName}");
                return Status.Failure;
            }

            enemyBase?.SetJumpTarget(skillTarget.transform.position);
        }

        if (!skillController.ExecuteSkill(step.Skill))
        {
            Debug.LogWarning($"[{GetType().Name}] 스킬 실행 실패: {step.Skill.SkillName}");
            return Status.Failure;
        }

        LogDebug($"패턴 실행: {activePattern.PatternName} / Step={currentStepIndex} / Skill={step.Skill.SkillName}");
        return Status.Running;
    }

    /// <summary>
    /// 충전 대기를 시작합니다. 전조 이상상태를 부여하고 데미지 추적을 시작합니다.
    /// </summary>
    private void StartChargeWait(PatternStep step)
    {
        isChargeWaiting = true;
        activeChargeData = step.ChargeData;
        chargeEndTime = Time.time + step.Duration;
        chargeAccumulatedDamage = 0f;

        float damageRatio = activeChargeData != null ? activeChargeData.RequiredDamageRatio : 0.1f;
        chargeRequiredDamage = bossEnemy.MaxHealth * damageRatio;
        chargeTelegraphApplied = false;

        if (enemyBase != null)
            enemyBase.OnDamageTaken += OnChargeDamageTaken;

        if (activeChargeData != null && activeChargeData.TelegraphAbnormality != null && abnormalityManager != null)
        {
            abnormalityManager.ApplyAbnormality(activeChargeData.TelegraphAbnormality, GameObject);
            chargeTelegraphApplied = true;
        }

        LogDebug($"충전 대기 시작: 필요 피해={chargeRequiredDamage:F1} / 대기={step.Duration:F1}s");
    }

    /// <summary>
    /// 충전 대기를 종료합니다. 전조 이상상태를 제거하고 데미지 추적을 해제합니다.
    /// </summary>
    private void EndChargeWait(bool broken)
    {
        isChargeWaiting = false;

        if (enemyBase != null)
            enemyBase.OnDamageTaken -= OnChargeDamageTaken;

        if (chargeTelegraphApplied && abnormalityManager != null && activeChargeData != null
            && activeChargeData.TelegraphAbnormality != null)
        {
            abnormalityManager.RemoveAbnormality(activeChargeData.TelegraphAbnormality);
            chargeTelegraphApplied = false;
        }

        if (broken && activeChargeData != null)
        {
            combatBehaviorContext.LastChargeStaggerDuration = activeChargeData.StaggerDuration;
        }

        activeChargeData = null;
    }

    /// <summary>
    /// 충전 중 보스가 받은 피해를 누적합니다.
    /// </summary>
    private void OnChargeDamageTaken(float damage)
    {
        if (!isChargeWaiting || damage <= 0f)
            return;

        chargeAccumulatedDamage += damage;
    }

    private bool IsReady()
    {
        return bossEnemy != null && enemyBase != null && skillController != null && combatBehaviorContext != null;
    }

    private void ResolveReferences()
    {
        if (bossEnemy == null)
            bossEnemy = GameObject.GetComponent<BossEnemy>();

        if (enemyBase == null)
            enemyBase = GameObject.GetComponent<EnemyBase>();

        if (skillController == null)
            skillController = GameObject.GetComponent<SkillController>();

        if (combatBehaviorContext == null)
            combatBehaviorContext = GameObject.GetComponent<BossCombatBehaviorContext>();

        if (navMeshAgent == null)
            navMeshAgent = GameObject.GetComponent<UnityEngine.AI.NavMeshAgent>();

        if (abnormalityManager == null)
            abnormalityManager = GameObject.GetComponent<AbnormalityManager>();
    }

    private void ClearRuntimeState()
    {
        if (isChargeWaiting)
            EndChargeWait(broken: false);

        activePattern = null;
        activeTarget = null;
        currentStepIndex = 0;
        isWaiting = false;
        waitEndTime = 0f;
    }
}