using AX.MessageSystem;
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class FourthGCamCtrl : MonoBehaviour {
    public Vector3 QuaterView = Vector3.zero;
    public float InitY;
    private static FourthGCamCtrl instance;
    private Camera cam;
    public static FourthGCamCtrl Instance
    {
        get
        {
            return instance;
        }
    }
    void Awake()
    {
        instance = this;
        QuaterView = transform.eulerAngles; //记录俯视视角
        InitY = transform.position.y;
        cam = this.GetComponent<Camera>();
    }
    private Transform target;
    private Vector3 preTargetPosition;
    private bool lookOver = false;
    private float height = 3; //查看人员模式下，摄像机高度
    private float distance = 2; //查看人员模式下，人与摄像机之间的距离
    private float dampTrace = 20.0f; //查看人员模式下，摄像机平滑追踪的变量
    private float lookingAtHeight = 3.5f;
    private float lookingAtDistance = 5;

    private bool isQuading = false;
    // Use this for initialization
    void Start () {
        MessageDispatcher.AddListener("OpenFourthG", EnableCamera);
        MessageDispatcher.AddListener("QuadrupleMode", DisableCamera);
        MessageDispatcher.AddListener("4GNobodySelected", NobodySelected);
        MessageDispatcher.AddListener("4GLookOver", LookOverTarget);
        MessageDispatcher.AddListener("4GCancelLookOver", CancelLookOver);
    }
    void OnEnable()
    {
        /*MessageDispatcher.AddListener("OpenFourthG", EnableCamera);
        MessageDispatcher.AddListener("QuadrupleMode", DisableCamera);
        MessageDispatcher.AddListener("4GNobodySelected", NobodySelected);
        MessageDispatcher.AddListener("4GLookOver", LookOverTarget);
        MessageDispatcher.AddListener("4GCancelLookOver", CancelLookOver);*/
    }
    void OnDisable()
    {
        /*MessageDispatcher.RemoveListener("OpenFourthG", EnableCamera);
        MessageDispatcher.RemoveListener("QuadrupleMode", DisableCamera);
        MessageDispatcher.RemoveListener("4GNobodySelected", NobodySelected);
        MessageDispatcher.RemoveListener("4GLookOver", LookOverTarget);
        MessageDispatcher.RemoveListener("4GCancelLookOver", CancelLookOver);*/
    }
    void OnDestroy()
    {
        MessageDispatcher.RemoveListener("OpenFourthG", EnableCamera);
        MessageDispatcher.RemoveListener("QuadrupleMode", DisableCamera);
        MessageDispatcher.RemoveListener("4GNobodySelected", NobodySelected);
        MessageDispatcher.RemoveListener("4GLookOver", LookOverTarget);
        MessageDispatcher.RemoveListener("4GCancelLookOver", CancelLookOver);
    }
    /// <summary>
    /// 开启4G图传时才激活此相机
    /// </summary>
    /// <param name="obj"></param>
    void EnableCamera(IMessage obj)
    {
        var value = (bool)obj.Data;
        //如果打开了4G图传，又处于四分屏模式，则此相机禁用
        if(value ==true && isQuading == true)
        {
            this.enabled = false;
            cam.enabled = false;            
        }
        //如果打开了4G图传，未处于四分屏模式，则此相机激活
        else if(value==true && isQuading == false)
        {
            this.enabled = true;
            cam.enabled = true;            
        }
        //如果关闭了4G图传，则禁用此相机
        else
        {
            this.enabled = false;
            cam.enabled = false;
        }
    }
    /// <summary>
    /// 开启四分屏模式时禁用此相机
    /// </summary>
    /// <param name="obj"></param>
    void DisableCamera(IMessage obj)
    {
        var value = (bool)obj.Data;
        isQuading = value;
        this.enabled = !value;
        cam.enabled = !value;        
    }
    // Update is called once per frame
    void Update () {
        //有目标人员并且相机激活时才执行
        if (target != null && cam.enabled==true)
        {
            if (!lookOver)
            {
                transform.position = new Vector3(target.position.x, transform.position.y, target.position.z);
            }
            else
            {   
                //相机的位置，在人员胸前
                transform.position = Vector3.Lerp(transform.position, target.position + (target.forward * distance) + (Vector3.up * height), Time.deltaTime * dampTrace);
                //transform.LookAt(target.position); 
                transform.LookAt(target.position + (target.forward * lookingAtDistance) + (Vector3.up * lookingAtHeight));                
            }
        }     
	}
    /// <summary>
    /// 查看人员视角
    /// </summary>
    /// <param name="obj"></param>
    private void LookOverTarget(IMessage obj)
    {
        var targetInfo = (CloneGameObjInfo)obj.Data;
        target = EntitiesManager.Instance.GetEntityByID(targetInfo.gameObjID).transform;        
        GetComponent<Camera>().orthographic = false; //改为透视视角
        lookOver = true;
    }
    /// <summary>
    /// 取消查看人员视角
    /// </summary>
    /// <param name="obj"></param>
    private void CancelLookOver(IMessage obj)
    {
        //恢复到俯视角度
        transform.eulerAngles = QuaterView;
        transform.position = new Vector3(transform.position.x, InitY, transform.position.z);
        GetComponent<Camera>().orthographic = true; //改回正交视角
        lookOver = false;        
    }
    /// <summary>
    /// 在4G图传中有人员被选中，相机跟随该人员
    /// </summary>
    /// <param name="tar"></param>
    public void SetTarget(Transform tar)
    {
        target = tar;
    }    
    /// <summary>
    /// 没有人员被选中，取消地图相机跟随
    /// </summary>
    /// <param name="obj"></param>
    void NobodySelected(IMessage obj)
    {
        //preTargetPosition = target.position;
        target = null;        
    }
}