using UnityEngine;
using System.Collections.Generic;

public class Buoyancy : MonoBehaviour
{
    private Ocean ocean;
    private float mag = 1f;
    private float ypos = 0.0f;
    private List<Vector3> blobs;
    private float ax = 2.0f;
    private float ay = 2.0f;
    private float dampCoeff = .2f;
    public bool sink = false;
    public float sinkForce = 3;
    private List<float> sinkForces;

    void Start()
    {

        rigidbody.centerOfMass = new Vector3(0.0f, -0.5f, 0.0f);

        Vector3 bounds = GetComponent<BoxCollider>().size;
        float length = bounds.z;
        float width = bounds.x;

        blobs = new List<Vector3>();

        int i = 0;
        float xstep = 1.0f / (ax - 1f);
        float ystep = 1.0f / (ay - 1f);

        sinkForces = new List<float>();

        float totalSink = 0;

        for (int x = 0; x < ax; x++)
        {
            for (int y = 0; y < ay; y++)
            {
                blobs.Add(new Vector3((-0.5f + x * xstep) * width, 0.0f, (-0.5f + y * ystep) * length) + Vector3.up * ypos);

                float force = Random.Range(0f, 1f);

                force = force * force;

                totalSink += force;

                sinkForces.Add(force);
                i++;
            }
        }

        // normalize the sink forces
        for (int j = 0; j < sinkForces.Count; j++)
        {
            sinkForces[j] = sinkForces[j] / totalSink * sinkForce;
        }

    }

    void OnEnable()
    {
        if (ocean == null)
            ocean = GameObject.FindGameObjectWithTag("Ocean").GetComponent<Ocean>();
    }

    void FixedUpdate()
    {
        int index = 0;
        Debug.Log(this.rigidbody.velocity);
        foreach (Vector3 blob in blobs)
        {

            Vector3 wpos = transform.TransformPoint(blob);
            float damp = rigidbody.GetPointVelocity(wpos).y;

            float buyancy = mag * (wpos.y);
            if (ocean.enabled && !sink)
                buyancy = mag * (wpos.y - ocean.GetWaterHeightAtLocation(wpos.x, wpos.z));

            if (sink)
            {
                buyancy = Mathf.Max(buyancy, -3) + sinkForces[index++];
            }
            rigidbody.AddRelativeForce(-Vector3.up * (buyancy + dampCoeff * damp), ForceMode.Impulse);
            //rigidbody.AddForceAtPosition(-Vector3.up * (buyancy + dampCoeff * damp), wpos);
        }
    }

    // Call this void when you want your boat or any object to sink more naturally
    public void Sink(bool isActive)
    {
        sink = isActive;
    }
}