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

[RequireComponent(typeof(AudioSource))]
[RequireComponent(typeof(LineRenderer))]
public class Visualiser : MonoBehaviour
{
    public int              _Samples = 100; // The number of samples we will sample the audiosource with. higher = lower performance but more points
    public float            _Scale = 1.0f;  // The scale of the audio sample
    public float            _Offset = 1.0f; // the offset from center for our circle
    public float            _ColorMul = 1.0f;
    public float            _LerpSpeed = 1.0f;

    public AudioClip        _AudioClip;     // Our audio clip

    public Color            _LowColor;
    public Color            _HighColor;

    private AudioSource     _AudioSource;
    private LineRenderer    _LineRenderer;

    // Start is called before the first frame update
    void Start()
    {
        _AudioSource    = GetComponent<AudioSource>();
        _LineRenderer   = GetComponent<LineRenderer>();

        _AudioSource.clip = _AudioClip;
        _AudioSource.Play();
    }


    // Update is called once per frame
    void Update()
    {
        float[] data = new float[_Samples]; // Create a basic array to store sample data
        _AudioSource.clip.GetData(data, _AudioSource.timeSamples); // Sample the track at the current timestamp

        // We add 1 extra so we can loop to the start
        _LineRenderer.positionCount = _Samples + 1;

        // For each sample...
        float avg = 0.0f;

        for (int i = 0; i < _Samples; ++i)
        {
            // Calculate the angle in degrees and convert to radians
            float a = ((360.0f / _Samples) * i) * Mathf.Deg2Rad;

            // Calculate the radius of the point, this will be our sample data
            // multiplied by a scale added to an offset
            float r = (data[i] * _Scale) + _Offset;

            // Calculate points around the circle
            float x = r * Mathf.Sin(a);
            float y = r * Mathf.Cos(a);

            // lerp line point
            Vector3 currentPosition = _LineRenderer.GetPosition(i);
            Vector3 newPosition = Vector3.Lerp(currentPosition, new Vector3(x, y, 0), _LerpSpeed * Time.deltaTime);

            _LineRenderer.SetPosition(i, newPosition);

            // Sometimes sample can be negative so abs it
            avg += Mathf.Abs(data[i]);
        }

        // Get avg
        avg = avg / (float)_Samples;

        Color c = Color.Lerp(_LowColor, _HighColor, avg * _ColorMul);

        // Create color gradient
        Gradient gradient = new Gradient();
        gradient.SetKeys(
            new GradientColorKey[] { new GradientColorKey(c, 0.0f), new GradientColorKey(c, 1.0f) },
            new GradientAlphaKey[] { new GradientAlphaKey(1.0f, 0.0f), new GradientAlphaKey(1.0f, 1.0f) }
        );
        _LineRenderer.colorGradient = gradient;

        // Loop to the start
        _LineRenderer.SetPosition(_Samples, _LineRenderer.GetPosition(0));
    }
}