using System;
using System.Collections;
using System.Collections.Generic;
using Unity.VisualScripting;
using UnityEngine;
using Random = UnityEngine.Random;

public class CameraFollow : MonoBehaviour
{
    public UpdateFrameType UpdateType;

    public Transform target;
    public Vector2 offset;
    public float yMinLimit, yMaxLimit;
    public float xSpeed, ySpeed;

    public float lookSensitivity;
    public float distance = 3;

    public float x, y;
    public bool isAiming= false;
    public float aimingFovIncrease = -20;
    [Header("Moving effects")]
    public float movingShakeIntensity;
    float defaultFov;
    public float movingFovIncrease = 10;
    public float movingZoomDist=1;
    public float movingEffectsSpeed = 0.4f;
    public float movingEffectsThershold;
    public float currentTargetSpeed;

    public static CameraFollow instance;
    public bool isViewObstructed;
    public float obstacleAvoidanceDistMult = 2f;
    public float pitchZoomThreshold = -25;
    public float pitchZoomDist = 1.5f;
    private void Awake()
    {
        instance = this;
        isPaused = false;
        defaultFov = Camera.main.fieldOfView;
    }

    void Start(){
        SettingsManager.instance.OnSettingsChanged.AddListener(OnSettingsChanged);
        OnSettingsChanged();
    }

    void OnSettingsChanged(){
        lookSensitivity = PlayerPrefs.GetFloat(SettingsManager.LOOKSENS_PREF_KEY);

        movingFovIncrease = SettingsManager.instance.cameraFovSlider.value;
        movingZoomDist = SettingsManager.instance.cameraZoomSlider.value;
    }

    // Update is called once per frame
    void Update()
    {
        
        if(UpdateType == UpdateFrameType.Normal) { UpdateFrame(); }

    }

    private void LateUpdate()
    {
        x += Input.GetAxis("Mouse X") * xSpeed * 0.02f * lookSensitivity;
        y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02f * lookSensitivity;

        if(UpdateType == UpdateFrameType.Late) { UpdateFrame(); }
    }

    private void FixedUpdate()
    {
        if(UpdateType == UpdateFrameType.Fixed) { UpdateFrame(); }
    }

    private bool isPaused = false;
    public static void Pause(){
        instance.isPaused = true;
    }

    public static void Resume(){
        instance.isPaused = false;
    }

    Vector3 targetLastPos;
    float movingEffectOffsetY = 0;
    float obstacleOffsetY=0;
    float pitchZoom=0;
    void UpdateFrame()
    {
        if(isPaused){return;}
        if(target == null) { return; }
        // currentTargetSpeed = (target.position - targetLastPos).sqrMagnitude;
        // targetLastPos = target.position;
        if (distance < 2) distance = 2;
       // distance -= Input.GetAxis("Mouse ScrollWheel") * 2;
        
        var pos = Input.mousePosition;
        var dpiScale = 1f;
        if (Screen.dpi < 1) dpiScale = 1;
        if (Screen.dpi < 200) dpiScale = 1;
        else dpiScale = Screen.dpi / 200f;

        if (pos.x < 380 * dpiScale && Screen.height - pos.y < 250 * dpiScale) return;

        // comment out these two lines if you don't want to hide mouse curser or you have a UI button 
        Cursor.visible = UIManager.isPaused;
        Cursor.lockState = UIManager.isPaused ? CursorLockMode.None:CursorLockMode.Locked;

        float fovDelta = 0;
        if(currentTargetSpeed > movingEffectsThershold){
            fovDelta = movingFovIncrease;
            movingEffectOffsetY = Mathf.Lerp(movingEffectOffsetY, movingZoomDist, movingEffectsSpeed);
        }else{
            fovDelta =0;
            movingEffectOffsetY = Mathf.Lerp(movingEffectOffsetY, 0, movingEffectsSpeed);
        }

        float m_obstacleZoomDist =0;
        isViewObstructed=false;

        RaycastHit hit = new RaycastHit();
        if(Physics.Linecast(target.position + (transform.forward * -obstacleAvoidanceDistMult * 2), target.position,out hit)){
            if(hit.collider.tag == "Player"){}else{
                // m_obstacleZoomDist = Vector3.Distance(transform.position, hit.point) * obstacleAvoidanceDistMult;
                m_obstacleZoomDist=obstacleAvoidanceDistMult;
                isViewObstructed=true;
            }
        }



        obstacleOffsetY = Mathf.Lerp(obstacleOffsetY, m_obstacleZoomDist, movingEffectsSpeed*5f);

        if(isAiming){
            fovDelta = aimingFovIncrease;
        }

        Camera.main.fieldOfView = Mathf.Lerp(Camera.main.fieldOfView, defaultFov + fovDelta, movingEffectsSpeed *(isAiming ? 10f:1));

        
        y = ClampAngle(y, yMinLimit, yMaxLimit);
        var rotation = Quaternion.Euler(y, x, 0);
        var position = rotation * new Vector3(0.0f, 0.0f, -distance) + target.transform.position;

        pitchZoom = Mathf.Lerp(pitchZoom,y < pitchZoomThreshold ? pitchZoomDist : 0, movingEffectsSpeed);
        position += transform.right * offset.x;
        position += transform.forward *( offset.y + movingEffectOffsetY + obstacleOffsetY + pitchZoom);

        transform.rotation = rotation;
        transform.position = position;


        if (Mathf.Abs(prevDistance - distance) > 0.001f)
        {
            prevDistance = distance;
            var rot = Quaternion.Euler(y, x, 0);
            var po = rot * new Vector3(0.0f, 0.0f, -distance) + target.transform.position;
            transform.rotation = rot;
            transform.position = po;
        }

        
        
        if(shakeIndex>0){
            shakeIndex--;
            float progression = (float)shakeIndex / (float)SHAKE_FRAMES;
            transform.position += new Vector3(Random.Range(-1f,1f),Random.Range(-1f,1f),Random.Range(-1f,1f)) * shakeIntensity * progression;
        }
    }

    public int shakeIndex =0;
    private float shakeIntensity;

    const int SHAKE_FRAMES = 25;
    public static void Shake(float intensity){
        instance.shakeIndex = SHAKE_FRAMES;
        instance.shakeIntensity = Mathf.Clamp(intensity,0,0.5f);
    }

    float prevDistance;


    static float ClampAngle(float angle, float min, float max)
    {
        if (angle < -360)
            angle += 360;
        if (angle > 360)
            angle -= 360;
        return Mathf.Clamp(angle, min, max);
    }
}


public enum UpdateFrameType
{
    Normal,
    Fixed,
    Late
}