using UnityEngine;

namespace BrewMonster
{
    /// <summary>
    /// Meteoric movement (falls from sky).
    /// Mirrors C++ CGfxMeteoricMove exactly (A3DSkillGfxEvent2.cpp:144-188).
    /// 流星移动（从天空坠落），完全镜像C++ CGfxMeteoricMove。
    /// </summary>
    public class CGfxMeteoricMove : CGfxMoveBase
    {
        protected Vector3 m_vFallVel;
        protected float m_fRadius;

        private const float _fall_height = 10.0f; // fall height, same as C++
        private const float _fall_speed = 8.0f; // fall speed (units per second), same as C++

        public CGfxMeteoricMove(GfxMoveMode mode) : base(mode)
        {
            m_fRadius = 2.0f; // default radius, same as C++
        }

        /// <summary>
        /// Initialize meteoric movement above target.
        /// 在目标上方初始化流星移动。
        /// </summary>
        public override void StartMove(Vector3 vHost, Vector3 vTarget)
        {
            m_vPos = vTarget;
            m_vPos.y += _fall_height;

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

            m_vMoveDir = -Vector3.up;
            m_vFallVel = _fall_speed * m_vMoveDir;
        }

        /// <summary>
        /// Tick meteoric movement. Returns true when hits ground.
        /// 更新流星移动。当撞击地面时返回true。
        /// </summary>
        public override bool TickMove(uint dwDeltaTime, Vector3 vHostPos, Vector3 vTargetPos)
        {
            m_vPos += m_vFallVel * (dwDeltaTime / 1000.0f);
            return m_vPos.y <= vTargetPos.y;
        }

        /// <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
        }
    }
}