using UnityEngine;


public class Boid : MonoBehaviour {
    public float speed = 0.2f;
    public int neighbourCount = 0;
    public float inertia = 0.2f;
    public float alignmentForce = 1.0f;
    public float cohesionForce = 1.0f;
    public float separationForce = 1.0f;
    public float separationDistance = 0.5f;
    public float bodyForce = 1;

    public SwarmControl sc;
    public Vector3 velocity = Vector3.zero;
    public Vector3 acceleration = Vector3.zero;

    readonly Collider[] results = new Collider[10];

    public NeuroidNetwork neuroidNet = new();
    public Neuroid bodyVector;
    public Neuroid cohesion;
    public Neuroid alignment;
    public Neuroid separation;
    public Neuroid target;

    public Neuroid totalForce;

    public int id;

    void Awake() {
        this.id = this.GetInstanceID();

        sc = FindFirstObjectByType<SwarmControl>();

        cohesion = new(neuroidNet) { name = "Cohesion", mode = Neuroid.Mode.Sum };
        alignment = new(neuroidNet) { name = "Alignment", mode = Neuroid.Mode.Average };
        separation = new(neuroidNet) { name = "Separation", mode = Neuroid.Mode.Sum };
        target = new(neuroidNet) { name = "Target", mode = Neuroid.Mode.Sum };


        totalForce = new(neuroidNet) { name = "Total force", mode = Neuroid.Mode.Sum };
        totalForce.GetInputFrom(alignment, sc.alignmentForce);
        totalForce.GetInputFrom(cohesion, sc.cohesionForce);
        totalForce.GetInputFrom(separation, sc.separationForce);
        totalForce.GetInputFrom(target, sc.bodyForce);
    }

    void Update() {
        Physics.OverlapSphereNonAlloc(this.transform.position, 10, results);
        neighbourCount = 0;

        cohesion.ResetWeights();
        alignment.ResetWeights();
        separation.ResetWeights();

        foreach (Collider c in results) {
            if (c == null || c as CapsuleCollider == null)
                continue;

            Boid neighbour = c.GetComponentInParent<Boid>();
            if (neighbour == null || neighbour == this)
                continue;

            Vector3 localPosition = neighbour.transform.position - this.transform.position;
            Vector3 relativeVelocity = neighbour.velocity - this.velocity;

            int id = neighbour.GetInstanceID();

            Vector3 separationForce = -localPosition / localPosition.sqrMagnitude;
            // which is equivalent to -(localPosition.normalized / localPosition.magnitude)

            separation.SetInput(id, separationForce, sc.separationDistance);
            cohesion.SetInput(id, localPosition);
            alignment.SetInput(id, relativeVelocity);

            neighbourCount++;
        }

        Vector3 totalForceVector = totalForce.outputValue;
        //Debug.DrawRay(this.transform.position, totalForceVector, Color.magenta);

        this.velocity = (1 - sc.inertia) * (totalForceVector * Time.deltaTime) + sc.inertia * velocity + (sc.speed * transform.forward);
        //this.velocity = Vector3.ClampMagnitude(this.velocity, sc.speed);

        this.transform.position += this.velocity * Time.deltaTime;

        if (this.velocity != Vector3.zero) {
            Quaternion targetRotation = Quaternion.LookRotation(this.velocity);
            transform.rotation = Quaternion.Slerp(transform.rotation, targetRotation, Time.deltaTime * 2f); // Adjust the speed of rotation        
        }
    }

}