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

public class AgentController : MonoBehaviour
{
    public GameObject parameterContainerObj;
    public GameObject environmentObj;
    public GameObject enemyContainerObj;
    public GameObject sceneBlockContainerObj;
    public GameObject environmentUIControlObj;
    public GameObject targetControllerObj;
    public GameObject HUDObj;
    public Camera fpsCam;

    [Header("GetAxis() Simulate")]
    public float moveSpeed = 9.0f;

    public float vX = 0f;
    public float vZ = 0f;
    public Vector3 nowMovement;
    public float acceleration = 0.9f; // 加速度
    public float mouseXSensitivity = 100;
    public float mouseYSensitivity = 200;
    public float yRotation = 0.1f;//定义一个浮点类型的量，记录‘围绕’X轴旋转的角度

    private List<float> spinRecord = new List<float>();
    private bool lockMouse;
    private float damage;
    private float fireRate;
    private bool lockCameraX;
    private bool lockCameraY;

    // environment
    private float lastShootTime = 0.0f;

    private int enemyKillCount = 0;
    private Vector3 killEnemyPosition;
    public bool defaultTPCamera = true;

    [System.NonSerialized] public bool gunReadyToggle = true;
    private string myTag = "";
    private float lastEnemyFacingDistance = 0f; // record last enemy facing minimum distance
    private float lastTargetFacingDistance = 0f; // record last target facing minimum distance

    // scripts
    private RaySensors raySensors;

    private CharacterController playerController;
    private ParameterContainer paramContainer;
    private SceneBlockContainer blockContainer;
    private TargetController targetCon;

    private void Start()
    {
        // initialize scripts
        paramContainer = parameterContainerObj.GetComponent<ParameterContainer>();
        blockContainer = sceneBlockContainerObj.GetComponent<SceneBlockContainer>();
        targetCon = targetControllerObj.GetComponent<TargetController>();
        raySensors = GetComponent<RaySensors>();
        playerController = this.transform.GetComponent<CharacterController>();

        // initialize Environment parameters
        lockMouse = paramContainer.lockMouse;
        damage = paramContainer.damage;
        fireRate = paramContainer.fireRate;
        lockCameraX = paramContainer.lockCameraX;
        lockCameraY = paramContainer.lockCameraY;

        // initialize remainTime
        // this agent's tag
        myTag = gameObject.tag;
    }

    #region Agent Move Control

    public void MoveAgent(int vertical, int horizontal)
    {
        // Vector3 nowMovement;
        if (horizontal != 0)//当按下按键（水平方向）
        {
            if (vX < moveSpeed && vX > -moveSpeed)//当前速度小于最大速度
            {
                vX += (float)horizontal * acceleration;//增加加速度
            }
            else
            {
                //防止在一瞬间切换输入时速度仍保持不变
                if ((vX * horizontal) > 0)//输入与当前速度方向同向
                {
                    vX = (float)horizontal * moveSpeed; //限制最大速度
                }
                else
                {
                    vX += (float)horizontal * acceleration;//增加加速度
                }
            }
        }
        else
        {
            if (Math.Abs(vX) > 0.001)
            {
                vX -= (vX / Math.Abs(vX)) * acceleration;//减少加速度
            }
            else
            {
                vX = 0;
            }
        }

        if (vertical != 0)//当按下按键（垂直方向）
        {
            if (vZ < moveSpeed && vZ > -moveSpeed)//当前速度小于最大速度
            {
                vZ += (float)vertical * acceleration;//增加加速度
            }
            else
            {
                if ((vZ * vertical) > 0)//输入与当前速度方向同向
                {
                    vZ = (float)vertical * moveSpeed; //限制最大速度
                }
                else
                {
                    vZ += (float)vertical * acceleration;//增加加速度
                }
            }
        }
        else
        {
            if (Math.Abs(vZ) > 0.001)
            {
                vZ -= (vZ / Math.Abs(vZ)) * acceleration;//减少加速度
            }
            else
            {
                vZ = 0;
            }
        }
        nowMovement = (transform.forward * vZ + transform.right * vX);
        //PlayerController下的.Move为实现物体运动的函数
        //Move()括号内放入一个Vector3类型的量，本例中为Player_Move
        if (nowMovement.magnitude > moveSpeed)
        {
            nowMovement = nowMovement.normalized * moveSpeed;
        }
        playerController.Move(nowMovement * Time.deltaTime);
        // update Key Viewer
    }

    #endregion Agent Move Control

    #region Camera Control

    public void CameraControl(float Mouse_X, float Mouse_Y)
    {
        //Mouse_X = Input.GetAxis("Mouse X") * MouseSensitivity * Time.deltaTime;
        //Debug.Log(Input.GetAxis("Mouse X"));
        //Mouse_Y = Input.GetAxis("Mouse Y") * MouseSensitivity * Time.deltaTime;
        if (lockCameraX)
        {
            Mouse_X = 0;
        }
        if (lockCameraY)
        {
            Mouse_Y = 0;
        }
        yRotation = yRotation - Mouse_Y;
        //xRotation值为正时，屏幕下移，当xRotation值为负时，屏幕上移
        //当鼠标向上滑动，Mouse_Y值为正,xRotation-Mouse_Y的值为负,xRotation总的值为负，屏幕视角向上滑动
        //当鼠标向下滑动，Mouse_Y值为负,xRotation-Mouse_Y的值为正,xRotation总的值为正，屏幕视角向下滑动
        //简单来说就是要控制鼠标滑动的方向与屏幕移动的方向要相同

        //limit UP DOWN between -90 -> 90
        yRotation = Mathf.Clamp(yRotation, -90f, 90f);

        //相机左右旋转时，是以Y轴为中心旋转的，上下旋转时，是以X轴为中心旋转的
        transform.Rotate(Vector3.up * Mouse_X);
        //Vector3.up相当于Vector3(0,1,0),CameraRotation.Rotate(Vector3.up * Mouse_X)相当于使CameraRotation对象绕y轴旋转Mouse_X个单位
        //即相机左右旋转时，是以Y轴为中心旋转的，此时Mouse_X控制着值的大小

        //相机在上下旋转移动时，相机方向不会随着移动，类似于低头和抬头，左右移动时，相机方向会随着向左向右移动，类似于向左向右看
        //所以在控制相机向左向右旋转时，要保证和父物体一起转动
        fpsCam.transform.localRotation = Quaternion.Euler(yRotation, 0, 0);
        //this.transform指这个CameraRotation的位置,localRotation指的是旋转轴
        //transform.localRotation = Quaternion.Eular(x,y,z)控制旋转的时候，按照X-Y-Z轴的旋转顺规
        //即以围绕X轴旋转x度，围绕Y轴旋转y度，围绕Z轴旋转z度
        //且绕轴旋转的坐标轴是父节点本地坐标系的坐标轴
    }

    #endregion Camera Control

    #region Reward Functions

    // ballistic 射击弹道处理，并返回获得reward
    private float Ballistic(int shootState)
    {
        Vector3 point = new Vector3(fpsCam.pixelWidth / 2, fpsCam.pixelHeight / 2, 0);//发射位置
        Ray ray = fpsCam.ScreenPointToRay(point);
        RaycastHit hit;
        // Debug.DrawRay(ray.origin, ray.direction * 100, Color.blue);
        //按下鼠标左键
        if (shootState != 0 && gunReadyToggle == true)
        {
            lastShootTime = Time.time;
            if (Physics.Raycast(ray, out hit, 100))
            {
                if (hit.collider.tag != myTag && hit.collider.tag != "Wall")
                {
                    // kill enemy
                    GameObject gotHitObj = hit.transform.gameObject;//获取受到Ray撞击的对象
                    gotHitObj.GetComponent<States>().ReactToHit(damage, gameObject);
                    shootState = 0;
                    return targetCon.HitEnemyReward(gotHitObj.transform.position);
                }
            }
            if (targetCon.targetTypeInt == (int)SceneBlockContainer.Targets.Attack)
            {
                // while if attack mode
                float targetDis = Vector3.Distance(blockContainer.nowBlock.transform.position, transform.position);
                if (targetDis <= raySensors.viewDistance)
                {
                    // Debug.DrawRay(new Vector3(0,0,0), viewPoint, Color.red);
                    if (Vector3.Distance(ray.origin + (ray.direction * targetDis), blockContainer.nowBlock.transform.position) <= blockContainer.nowBlock.firebasesAreaDiameter / 2)
                    {
                        // im shooting at target but didn't hit enemy
                        // Debug.DrawRay(ray.origin, viewPoint-ray.origin, Color.blue);
                        return paramContainer.shootTargetAreaReward;
                    }
                }
            }
            shootState = 0;
            return paramContainer.shootReward;
        }
        else if (shootState != 0 && gunReadyToggle == false)
        {
            // shoot without ready
            shootState = 0;
            return paramContainer.shootWithoutReadyReward;
        }
        else
        {
            // do not shoot
            shootState = 0;
            return paramContainer.nonReward;
        }
    }

    private float FacingReward()
    {
        float nowReward = 0;
        bool isFacingtoEnemy = false;
        float enemyFacingDistance = 0f;
        Ray ray = fpsCam.ScreenPointToRay(new Vector3(fpsCam.pixelWidth / 2, fpsCam.pixelHeight / 2, 0));
        if (targetCon.targetTypeInt == (int)SceneBlockContainer.Targets.Free)
        {
            //free mode
            RaycastHit hit;
            if (Physics.Raycast(ray, out hit, 100))
            {
                // facing to an enemy
                if (hit.collider.tag != myTag && hit.collider.tag != "Wall")
                {
                    nowReward = paramContainer.facingReward;
                    isFacingtoEnemy = true;
                }
            }
            if (raySensors.inViewEnemies.Count > 0 && !isFacingtoEnemy)
            {
                // have enemy in view
                List<float> projectionDis = new List<float>();
                foreach (GameObject theEnemy in raySensors.inViewEnemies)
                {
                    // for each enemy in view
                    Vector3 projection = Vector3.Project(theEnemy.transform.position - transform.position, (ray.direction * 10));
                    Vector3 verticalToRay = transform.position + projection - theEnemy.transform.position;
                    projectionDis.Add(verticalToRay.magnitude);
                    // Debug.Log("enemy!" + verticalToRay.magnitude);
                    // Debug.DrawRay(transform.position, (ray.direction * 100), Color.cyan);
                    // Debug.DrawRay(transform.position, theEnemy.transform.position - transform.position, Color.yellow);
                    // Debug.DrawRay(transform.position, projection, Color.blue);
                    // Debug.DrawRay(theEnemy.transform.position, verticalToRay, Color.magenta);
                }
                enemyFacingDistance = projectionDis.Min();
                if (enemyFacingDistance <= lastEnemyFacingDistance)
                {
                    // closing to enemy
                    nowReward = 1 / MathF.Sqrt(paramContainer.facingInviewEnemyDisCOEF * enemyFacingDistance + 0.00001f);
                }
                else
                {
                    nowReward = 0;
                }
                // enemy in view Reward
                lastEnemyFacingDistance = enemyFacingDistance;
                if (nowReward >= paramContainer.facingReward) nowReward = paramContainer.facingReward; // limit
                if (nowReward <= -paramContainer.facingReward) nowReward = -paramContainer.facingReward; // limit
                // Debug.Log("ninimum = " + nowReward);
            }
        }
        else if (targetCon.targetTypeInt == (int)SceneBlockContainer.Targets.Attack)
        {
            // attack mode
            // Target to Agent distance
            float targetDis = Vector3.Distance(blockContainer.nowBlock.transform.position, transform.position);
            // center of screen between target's distance
            float camCenterToTarget = Vector3.Distance(ray.origin + (ray.direction * targetDis), blockContainer.nowBlock.transform.position);
            if (targetDis <= raySensors.viewDistance)
            {
                // Debug.DrawRay(new Vector3(0,0,0), viewPoint, Color.red);
                // while center of screen between target's distance is lower than firebasesAreaDiameter
                // while facing to target
                if (camCenterToTarget <= blockContainer.nowBlock.firebasesAreaDiameter / 2)
                {
                    // Debug.DrawRay(ray.origin, viewPoint-ray.origin, Color.blue);

                    nowReward = paramContainer.facingReward;
                }
                else
                {
                    // while not facing to target
                    nowReward = (lastTargetFacingDistance - camCenterToTarget) * paramContainer.facingTargetReward;
                }
            }
            // update lastTargetFacingDistance
            lastTargetFacingDistance = camCenterToTarget;
        }
        return nowReward;
    }

    public float RewardCalculate(float sceneReward, float mouseX, float movement, int shootState)
    {
        float epreward = 0f;
        // 击杀reward判断
        if (enemyKillCount > 0)
        {
            for (int i = 0; i < enemyKillCount; i++)
            {
                // get
                epreward += targetCon.KillReward(killEnemyPosition);
            }
            enemyKillCount = 0;
        }
        else
        {
            enemyKillCount = 0;
        }
        // 射击动作reward判断
        epreward += Ballistic(shootState) + sceneReward;
        // facing reward
        epreward += FacingReward();
        // Penalty
        // spin penalty
        spinRecord.Add(mouseX);
        if (spinRecord.Count >= paramContainer.spinRecordMax)
        {
            spinRecord.RemoveAt(0);
        }
        float spinPenaltyReward = Math.Abs(spinRecord.ToArray().Sum() * paramContainer.spinPenalty);
        if (spinPenaltyReward >= paramContainer.spinPenaltyThreshold)
        {
            epreward -= spinPenaltyReward;
        }
        else
        {
            epreward -= Math.Abs(mouseX) * paramContainer.mousePenalty;
        }
        // move penalty
        if (movement != 0)
        {
            epreward -= paramContainer.movePenalty;
        }
        return epreward;
    }

    #endregion Reward Functions

    // GotKill 获得击杀时用于被呼出
    public void KillRecord(Vector3 killEnemyPosition)
    {
        enemyKillCount += 1;
        this.killEnemyPosition = killEnemyPosition;
    }

    public void UpdateLockMouse()
    {
        // lock mouse based on paramContainer lockMouse
        if (lockMouse)
        {
            Cursor.lockState = CursorLockMode.Locked;
        }
    }

    public void UpdateGunState()
    {
        // update gun state
        if ((Time.time - lastShootTime) >= fireRate)
        {
            gunReadyToggle = true;
        }
        else
        {
            gunReadyToggle = false;
        }
    }
}