using UnityEngine;

namespace BrewMonster
{
    /// <summary>
    /// Instant-hit movement (no flight). Used for melee/instant skills.
    /// Mirrors C++ CGfxOnTargetMove exactly (A3DSkillGfxEvent2.cpp:297-322).
    /// 瞬间命中移动（无飞行）。用于近战/瞬发技能。
    /// </summary>
    public class CGfxOnTargetMove : CGfxMoveBase
    {
        protected float m_fRadius;
        protected Vector3 m_vOffset;

        public CGfxOnTargetMove(GfxMoveMode mode) : base(mode)
        {
            m_HitPos = GfxHitPos.enumHitBottom;
            m_fRadius = 0;
        }

        /// <summary>
        /// Set position to target immediately. Cluster offset adds random radius.
        /// 立即将位置设置到目标。群集偏移添加随机半径。
        /// </summary>
        public override void StartMove(Vector3 vHost, Vector3 vTarget)
        {
            m_vPos = vTarget;
            m_vMoveDir = vTarget - vHost;
            m_vMoveDir.y = 0;
            if (Normalize(ref m_vMoveDir) == 0)
            {
                m_vMoveDir = Vector3.forward;
            }

            if (m_bOneOfCluser)
            {
                float fRandAng = Random.value * Mathf.PI * 2f;
                float fRadius = Random.value * m_fRadius;
                m_vOffset.x = Mathf.Cos(fRandAng) * fRadius;
                m_vOffset.z = Mathf.Sin(fRandAng) * fRadius;
                m_vOffset.y = 0;
                m_vPos += m_vOffset;
            }
            else
            {
                m_vOffset = Vector3.zero;
            }
        }

        /// <summary>
        /// Always returns false — hit is triggered by fly time timeout, NOT by TickMove.
        /// 始终返回false — 命中由飞行时间超时触发，而非TickMove。
        /// </summary>
        public override bool TickMove(uint dwDeltaTime, Vector3 vHostPos, Vector3 vTargetPos)
        {
            m_vPos = vTargetPos + m_vOffset;
            return false; // C++ returns false — hit triggered by fly time timeout
        }

        /// <summary>
        /// Override to also read radius from param value.
        /// 重写以从参数值中读取半径。
        /// </summary>
        public override void SetParam(GFX_SKILL_PARAM param)
        {
            base.SetParam(param);
            m_fRadius = param.value.fVal; // C# union access: param.value.fVal
        }
    }
}