using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Serialization;
using Quaternion = System.Numerics.Quaternion;

public class AnimatorController : MonoBehaviour
{
    [Header("Input")]
    public float speed;
    public bool jump;
    
    [Header("Player")]
    public float walkSpeed = 2.0f;
    public float runSpeed = 6.0f;
    [Range(0f,1f)]
    public float freeLookRange;
    public Transform head;
    public Transform lookAtTarget;
    public Camera playerCamera;
    
    [Space(10)]
    [Header("Jump")]
    //滞空后开始下落动画时间
    public float FallTimeout = 0.15f;

    //判断是否接地
    [Header("Player Grounded")]
    public LayerMask groundLayers;
    public float groundedOffset = -0.14f;
    public float groundedRadius = 0.28f;
    public bool grounded = true;
    
    //脚步声
    public AudioClip landingAudioClip;
    public AudioClip[] footstepAudioClips;
    [Range(0, 1)] public float footstepAudioVolume = 0.5f;
    
    private Animator _animator;
    private bool _hasAnimator;
    // animation IDs
    private int _animIDSpeed;
    private int _animIDGrounded;
    private int _animIDJump;
    private int _animIDFreeFall;
    // 滞空时间
    private float _fallTimeoutTimer;
    
    void Start()
    {
        _animIDSpeed = Animator.StringToHash("Speed");
        _animIDGrounded = Animator.StringToHash("Grounded");
        _animIDJump = Animator.StringToHash("Jump");
        _animIDFreeFall = Animator.StringToHash("FreeFall");
        _hasAnimator = TryGetComponent(out _animator);
        if(playerCamera==null) playerCamera=Camera.main;
    }

    // Update is called once per frame
    void FixedUpdate()
    {
        JumpAndGravity();
        GroundedCheck();
        Move();
        LookAtTarget();
    }
    
     private void JumpAndGravity()
    {
        if (grounded)
        {
            // 重置滞空时间
            _fallTimeoutTimer = FallTimeout;

            // 动画设为非空中状态
            if (_hasAnimator )
            {
                _animator.SetBool(_animIDJump, false);
                _animator.SetBool(_animIDFreeFall, false);
            }

            // 满足条件开始跳跃
            Debug.Log(jump + "*********" + _hasAnimator);
            if (jump)
            {
                if (_hasAnimator)
                {
                    _animator.SetBool(_animIDJump, true);
                }
                
            }
            jump = false;
        }
        else
        {
            // 计算滞空时间
            if (_fallTimeoutTimer >= 0.0f)
            {
                _fallTimeoutTimer -= Time.deltaTime;
            }
            else
            {
                // 滞空结束，开始播放下落动画
                if (_hasAnimator)
                {
                   _animator.SetBool(_animIDFreeFall, true);
                }
            }
            jump = false;
        }
    }
     
    // 检查指定位置的球体与地面接触，判断是否接地
    private void GroundedCheck()
    {
        
        Vector3 spherePosition = new Vector3(transform.position.x, transform.position.y - groundedOffset, transform.position.z);
        grounded = Physics.CheckSphere(spherePosition, groundedRadius, groundLayers, QueryTriggerInteraction.Ignore);
        
        if (_hasAnimator)
        {
            _animator.SetBool(_animIDGrounded, grounded);
        }
    }

    private void Move()
    {
        float animSpeed=0f;
        if (_hasAnimator)
        {
            if (speed >= 0 && speed <= walkSpeed)
            {
                animSpeed = RemapNum(speed, 0f, walkSpeed, 0f, 2f);
            }
            if (speed >walkSpeed)
            {
                speed = Mathf.Clamp(speed, 0f, 6.0f);
                animSpeed = RemapNum(speed, walkSpeed, runSpeed, 2f, 6f);
            }
            _animator.SetFloat(_animIDSpeed, animSpeed);
        }
    }

    private void LookAtTarget()
    {
        Vector3 cameraForward = playerCamera.transform.forward;
        if (Vector3.Dot(cameraForward, head.forward) < freeLookRange)
        {
            lookAtTarget.position = Vector3.Lerp(lookAtTarget.position ,head.position + head.forward,0.1f);
        }
        else
        {
            lookAtTarget.position =Vector3.Lerp(lookAtTarget.position ,head.position + cameraForward,0.1f); 
        }
    }
    
    private float RemapNum(float input, float oldMin, float oldMax, float newMin, float newMax)
    {
        float result = (newMax - newMin) / (oldMax - oldMin) * (input - oldMin) + newMin;
        return result;
    }

    //球体与地面接触判断触地可视
    private void OnDrawGizmosSelected()
    {
        Color transparentGreen = new Color(0.0f, 1.0f, 0.0f, 0.35f);
        Color transparentRed = new Color(1.0f, 0.0f, 0.0f, 0.35f);

        if (grounded) Gizmos.color = transparentGreen;
        else Gizmos.color = transparentRed;

        // when selected, draw a gizmo in the position of, and matching radius of, the grounded collider
        Gizmos.DrawSphere(new Vector3(transform.position.x, transform.position.y - groundedOffset, transform.position.z), groundedRadius);
    }
    
    private void OnFootstep(AnimationEvent animationEvent)
    {
        if (animationEvent.animatorClipInfo.weight > 0.5f)
        {
            if (footstepAudioClips.Length > 0)
            {
                var index = Random.Range(0, footstepAudioClips.Length);
                AudioSource.PlayClipAtPoint(footstepAudioClips[index], transform.transform.position, footstepAudioVolume);
            }
        }
    }

    private void OnLand(AnimationEvent animationEvent)
    {
        if (animationEvent.animatorClipInfo.weight > 0.5f)
        {
            AudioSource.PlayClipAtPoint(landingAudioClip, transform.position, footstepAudioVolume);
        }
    }
}