using System.Collections;
using System.Collections.Generic;
using UnityEngine;

/// <summary>
/// 弓箭手技能：迅捷三连 / 弱点锁定体系（1/3/6/10 级完整阶梯）
/// 1级【迅捷三连】：搭弓连续高速射出 3 支穿甲箭矢，单体快速倾泻火力
/// 3级【极速穿甲】：箭矢飞行速度 +35%，三连射总伤害提升 25%
/// 6级【弱点锁定】：伤害逐箭递增且第 3 箭必暴击；命中附加破甲标记，使目标受到的所有伤害 +30%（持续 4s）！
/// 10级【乱射风暴】：三连射升级为 6 支风暴连射；击杀目标后剩余箭矢自动散开弹射给周围其他敌人
/// </summary>
public class ArcherSkill : UnitSkill
{
    [Header("三连射配置")]
    [Tooltip("基础箭矢数量")]
    public int baseArrowCount = 3;

    [Tooltip("每支箭发射间隔(秒)")]
    public float arrowInterval = 0.12f;

    [Tooltip("技能箭矢基础速度")]
    public float baseProjectileSpeed = 22f;

    private Coroutine activeVolleyCoroutine;

    private void EnsureUnit()
    {
        if (unit == null)
        {
            unit = GetComponent<UnitBase>();
        }
    }

    public override void ReleaseSkill()
    {
        EnsureUnit();
        if (unit == null) return;

        WorldHealthBar healthBar = unit.GetComponent<WorldHealthBar>();
        if (healthBar == null || healthBar.IsDead) return;

        if (unit.Target == null) return;

        if (activeVolleyCoroutine != null)
        {
            StopCoroutine(activeVolleyCoroutine);
        }

        activeVolleyCoroutine = StartCoroutine(FireVolleyRoutine());
    }

    private IEnumerator FireVolleyRoutine()
    {
        EnsureUnit();
        if (unit == null) yield break;

        int level = unit.level;

        // 10级升级为 6 支箭；其余等级为 3 支
        int arrowCount = level >= 10 ? 6 : baseArrowCount;

        // 3级+ 箭速提升 35%
        float projSpeed = level >= 3 ? baseProjectileSpeed * 1.35f : baseProjectileSpeed;

        Debug.Log($"<color=green>【弓箭手释放技能】</color> 准备倾泻 {arrowCount} 连射（等级: {level}）！");

        for (int i = 0; i < arrowCount; i++)
        {
            // 目标死亡后自动切换给最近敌人
            GameObject currentTarget = unit.Target;
            if (currentTarget == null || !currentTarget.activeInHierarchy || IsTargetDead(currentTarget))
            {
                currentTarget = unit.FindNearestEnemyForSkill();
            }

            if (currentTarget == null)
            {
                break; // 全场无敌人提前结束
            }

            // 计算该支箭的伤害倍率与暴击
            float damageMultiplier = GetArrowDamageMultiplier(i, arrowCount, level);
            bool isGuaranteedCrit = (level >= 6 && i == arrowCount - 1); // 6级+ 最后一箭必定暴击
            bool applyVulnerability = (level >= 6 && i == arrowCount - 1); // 6级+ 最后一箭施加 4 秒 30% 易伤

            // 发射技能箭矢
            LaunchSkillArrow(currentTarget, damageMultiplier, projSpeed, isGuaranteedCrit, applyVulnerability);

            yield return new WaitForSeconds(arrowInterval);
        }

        activeVolleyCoroutine = null;
    }

    private float GetArrowDamageMultiplier(int index, int totalCount, int level)
    {
        // 1级：基础 70% 伤害/箭
        float baseMult = 0.70f;

        // 3级：三连射总伤害提升 25% (0.70 * 1.25 = 0.875)
        if (level >= 3 && level < 6)
        {
            baseMult *= 1.25f;
        }

        // 6级+【弱点锁定】：伤害逐箭递增
        if (level >= 6)
        {
            // 逐箭递增：例如第 1 箭 0.85，第 2 箭 1.05，最后一箭 1.35
            float step = (float)index / Mathf.Max(1, totalCount - 1);
            baseMult = Mathf.Lerp(0.85f, 1.35f, step);
        }

        return baseMult;
    }

    private void LaunchSkillArrow(GameObject targetObj, float damageMultiplier, float speed, bool forceCrit, bool applyVulnerability)
    {
        if (unit == null || unit.projectilePrefab == null || targetObj == null) return;

        Transform spawnPoint = unit.projectileSpawnPoint != null ? unit.projectileSpawnPoint : unit.transform;
        Vector3 spawnPos = spawnPoint.position;

        Vector3 direction = (targetObj.transform.position + Vector3.up * 0.8f - spawnPos).normalized;
        Quaternion rotation = Quaternion.LookRotation(direction);

        GameObject arrowObj = Instantiate(unit.projectilePrefab, spawnPos, rotation);

        float calculatedDamage = unit.attackPower * damageMultiplier;
        if (forceCrit || (unit.critRate > 0f && Random.value < unit.critRate))
        {
            calculatedDamage *= unit.critMultiplier;
        }

        // 接管 Arrow 碰撞，挂载自定义伤害与易伤回调
        var projectile = arrowObj.GetComponent<Projectile>();
        if (projectile != null)
        {
            // 技能箭不二次积攒能量
            projectile.Initialize(targetObj, calculatedDamage, unit.gameObject, speed, 5f, false);
        }

        // 6级+ 易伤监听逻辑：如果本箭命中了，自动给目标挂上 30% 易伤
        if (applyVulnerability)
        {
            StartCoroutine(ApplyVulnerabilityWhenHit(targetObj, 4.0f, 0.30f));
        }
    }

    private IEnumerator ApplyVulnerabilityWhenHit(GameObject targetObj, float duration, float ratio)
    {
        // 等待箭矢飞至命中（约 0.2 ~ 0.4 秒）
        yield return new WaitForSeconds(0.25f);

        if (targetObj != null && targetObj.activeInHierarchy)
        {
            var status = targetObj.GetComponentInParent<StatusEffectController>();
            if (status != null)
            {
                status.ApplyVulnerability(duration, ratio);
                Debug.Log($"<color=yellow>【弱点锁定】生效！</color> 目标 {targetObj.name} 陷入破甲易伤：受击伤害 +{ratio * 100:F0}%，持续 {duration} 秒！");
            }
        }
    }

    private bool IsTargetDead(GameObject targetObj)
    {
        if (targetObj == null) return true;
        var bar = targetObj.GetComponentInParent<WorldHealthBar>();
        return bar != null && bar.IsDead;
    }

    private void OnDestroy()
    {
        if (activeVolleyCoroutine != null)
        {
            StopCoroutine(activeVolleyCoroutine);
        }
    }
}