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

public class YeetController : MonoBehaviour
{
    public GameObject parent { get; set; }

    public float yeetVelocity = 5f;
    public float yeetDuration = 2f;
    public float windupSpeed = 0.01f;

    public enum YeetState { Unheld, Held, Yeeting };
    public YeetState yeetState { get; private set; } = YeetState.Unheld;

    private GameObject _child;
    private float m_time;

    private GameObject m_child;
    private GameObject m_body;

    private float m_velocityWindup;

    private LineRenderer m_lineRenderer;

    private void Awake()
    {
        m_body = this.gameObject;
    }

    public void Hold(GameObject child)
    {
        _child = child;
        _child.transform.parent = parent.transform;
        yeetState = YeetState.Held;

        m_lineRenderer = gameObject.AddComponent<LineRenderer>();
    }

    public void Yeet()
    {
        _child.transform.parent = null;
        _child.transform.rotation = parent.transform.rotation;
        _child.GetComponent<Rigidbody>().velocity = _child.transform.forward * m_velocityWindup + _child.transform.up * m_velocityWindup;
        yeetState = YeetState.Yeeting;
        m_time = yeetDuration;
        m_velocityWindup = 0;

        Destroy(m_lineRenderer);
    }

    void Start()
    {
 
    }

    void Update()
    {
        switch(yeetState)
        {
            case YeetState.Yeeting:
                m_time -= Time.deltaTime;

                if(m_time <= 0f)
                {
                    Debug.Log("YeetController.Update: Yeet finished");
                    yeetState = YeetState.Unheld; 
                }
                break;
            case YeetState.Held:
                // draw yeet lines

                if(m_velocityWindup < yeetVelocity)
                {
                    m_velocityWindup += windupSpeed;
                }

                Vector3 velocity = parent.transform.forward * m_velocityWindup + parent.transform.up * m_velocityWindup;

                float t;
                t = (-1f * velocity.y) / Physics.gravity.y;
                t = 2f * t;

                m_lineRenderer.positionCount = 10;
                Vector3 trajectoryPoint;

                for (int i = 0; i < m_lineRenderer.positionCount; i++)
                {
                    float time = t * i / (float)(m_lineRenderer.positionCount);
                    trajectoryPoint = parent.transform.position + velocity * time + 0.5f * Physics.gravity * time * time;
                    m_lineRenderer.SetPosition(i, trajectoryPoint);
                }
                break;
            case YeetState.Unheld:
                _child = null;
                break;
        }
    }

    private void OnTriggerEnter(Collider collider)
    {
        Debug.Log("PlayerInputController.OnTriggerEnter: arrived");
        m_child = collider.gameObject;
    }

    private void OnTriggerExit(Collider collider)
    { 
        m_child = null;
    }

    private void OnYeet()
    {
        parent = m_body;
        switch (yeetState)
        {
            case YeetController.YeetState.Unheld:
                if(m_child)
                    Hold(m_child);
                // Grab nearest baby
                break;
            case YeetController.YeetState.Held:
                Yeet();
                // Yeet baby
                break;
            case YeetController.YeetState.Yeeting:
                // Cooldown?
                break;
        }
    }

}