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

/// <summary>
/// primitive标记
/// </summary>
public enum PhysicsTag
{
    Player  = 1,      // 从属于玩家
    Oponent = 1 << 1, // 从属于对手
}

/// <summary>
/// primitive分类
/// </summary>
public enum PhysicsGroup
{
    Character, // 角色
    Prop,      // 物体
    Ground,    // 地面
    Wall,      // 墙面
}

public class PhysicsWorld : Singleton<PhysicsWorld>
{
    private int m_UpdateRate = 30;
    // 重力加速度
    private readonly Vector3 m_Gravity = new Vector3(0, -9.8f, 0);
    // 当前管理的碰撞体
    private List<PhysicsPrimitive> m_Primitives;
    private float m_TimeCount;

    public void Init()
    {
        m_Primitives = new List<PhysicsPrimitive>();
        m_TimeCount = Time.time;
    }

    public void AddPrimitive(PhysicsPrimitive prim)
    {
        if (prim == null)
            return;
        if(m_Primitives.Contains(prim))
        {
            Debug.LogError("PhysicsWorld已经存在此碰撞体，ID=" + prim.ID + ", 类型=" + prim.Tag);
            return;
        }
        m_Primitives.Add(prim);
    }

    public void RemovePrimitive(PhysicsPrimitive prim)
    {
        if (prim == null)
            return;
        m_Primitives.Remove(prim);
    }

    /// <summary>
    /// 物理系统已稳定的逻辑帧率执行
    /// </summary>
    public void Update()
    {
        float preTime = m_TimeCount;
        m_TimeCount = Time.time;
        float dt = m_TimeCount - preTime;
        while (dt > 1f / m_UpdateRate)
        {
            Tick();
            dt -= 1f / m_UpdateRate;
        }
        m_TimeCount -= dt;
    }

    private void Tick()
    {
        float deltaTime = 1f / m_UpdateRate;
        //Debug.Log("Physics Tick");

    }

}