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

public class AiShootBall : MonoBehaviour
{
    [SerializeField] Rigidbody soccerRb;

    [SerializeField] float force;

    [SerializeField] Transform target;

    [SerializeField] float curveStartForce;

    float timeToReachDestination;

    bool addCurve=false;

    float timeRemaining;
    // Start is called before the first frame update
    void Start()
    {
        Invoke("ShootBall", 2f);
        //ShootBall();
    }
    
    public void ShootBall()
    {
        //this will get the direction to reach the desitination
        Vector3 dir = target.position - transform.position;
        //then we normalize the value
        dir.Normalize();

        //way of discovering the time it will take to reach destination
        float distance = Vector3.Distance(target.position, transform.position);

        //this will get the time to reach the destination
        timeToReachDestination = TimeBetweenObjects(distance, force);

        //float forceNecessary = ForceNeededToReachDestination(distance, timeToReachDestination);

        //this will tell the code to add curve
        addCurve = true;
        //this will store the time remaining to add curve
        timeRemaining = timeToReachDestination;

        //we add the velocity to the rb
        soccerRb.velocity = dir * force;

        //this will add the initial curve force, so that we then add curve to the opossite direction
        soccerRb.velocity += new Vector3(-curveStartForce, 0, 0);
    }

    private void Update()
    {
        //if we are adding a curve, we decrease the countdown
        if (addCurve)
            timeRemaining -= Time.deltaTime;
    }

    private void FixedUpdate()
    {
        if (addCurve && timeRemaining > 0)
        {
            soccerRb.AddForce(new Vector3((curveStartForce + curveStartForce) / timeToReachDestination * Time.fixedDeltaTime, 0, 0), ForceMode.VelocityChange);   
        }
        //if the time has ended we tell the code to stop adding curve and we reset the curve timer
        else
        {
            addCurve = false;
            timeRemaining = 0;
        }
        
    }

    //this will find the time it will take to reach destination
    float TimeBetweenObjects(float distance, float force)
    {
        float timeBetweenObjects = distance / force;
        Debug.Log("Distance: " + distance + " time to reach: " + timeBetweenObjects + " force " + force);
        return timeBetweenObjects;
    }

    //this will find the force necessary to reach destinatiion
    float ForceNeededToReachDestination(float distance, float timeBetweenObjects)
    {
        //way of discovering force necessary to reach destination at seconds
        float forceNeeded = distance / timeBetweenObjects;
        Debug.Log("Force needed : " + forceNeeded);
        return forceNeeded;
    }
}