using System;
using UnityEngine;
using Logger = NewHorizons.Utility.Logger;

namespace NewHorizons.Components.Orbital
{
    public class TrackingOrbitLine : OrbitLine
    {
        private Vector3[] _vertices;
        private float _timer;
        private bool _firstTimeEnabled = true;

        public float TrailTime = 120f;

        public override void InitializeLineRenderer()
        {
            _lineRenderer.positionCount = _numVerts;
        }

        public override void OnValidate()
        {
            if (_numVerts < 0 || _numVerts > 4096) _numVerts = Mathf.Clamp(_numVerts, 0, 4096);
            if (_lineRenderer.positionCount != _numVerts) InitializeLineRenderer();
        }

        public override void Start()
        {
            base.Start();
            _vertices = new Vector3[_numVerts];

            enabled = true;
            _lineRenderer.enabled = false;
        }

        public override void OnEnterMapView()
        {
            if (_firstTimeEnabled)
            {
                ResetLineVertices();
                _firstTimeEnabled = false;
            }

            _lineRenderer.enabled = true;
        }

        public override void OnExitMapView()
        {
            _lineRenderer.enabled = false;
        }

        public override void Update()
        {
            try
            {
                var primary = _astroObject.GetPrimaryBody();
                var origin = primary == null ? Locator.GetRootTransform().position : primary.transform.position;

                _timer += Time.deltaTime;
                var updateTime = TrailTime / _numVerts;

                if (_timer > updateTime)
                {
                    for (var i = _numVerts - 1; i > 0; i--)
                    {
                        var v = _vertices[i - 1];
                        _vertices[i] = new Vector3(v.x, v.y, v.z);
                    }

                    _timer = 0;
                }

                _vertices[0] = transform.parent.position - origin;
                _lineRenderer.SetPositions(_vertices);

                transform.position = origin;
                transform.rotation = Quaternion.AngleAxis(0f, Vector3.up);

                var num2 = DistanceToTrackingOrbitLine(Locator.GetActiveCamera().transform.position);
                var widthMultiplier = Mathf.Min(num2 * (_lineWidth / 1000f), _maxLineWidth);
                var num3 = _fade ? 1f - Mathf.Clamp01((num2 - _fadeStartDist) / (_fadeEndDist - _fadeStartDist)) : 1f;
                _lineRenderer.widthMultiplier = widthMultiplier;
                _lineRenderer.startColor = new Color(_color.r, _color.g, _color.b, num3 * num3);
            }
            catch (Exception ex)
            {
                Logger.LogError($"Exception in OrbitLine for [{_astroObject?.name}] : {ex.Message}, {ex.StackTrace}");
                enabled = false;
            }
        }

        private float DistanceToTrackingOrbitLine(Vector3 point)
        {
            // Check against 3 points on the line
            var primary = _astroObject.GetPrimaryBody();
            point -= primary.transform.position;
            var dist1 = Vector3.Distance(point, _vertices[0]);
            var dist2 = Vector3.Distance(point, _vertices[_numVerts / 2]);
            var dist3 = Vector3.Distance(point, _vertices[_numVerts - 1]);

            return Mathf.Min(dist1, dist2, dist3);
        }

        public void ResetLineVertices()
        {
            var primary = _astroObject.GetPrimaryBody();
            var origin = primary == null ? Locator.GetRootTransform().position : primary.transform.position;

            transform.position = origin;
            transform.rotation = Quaternion.AngleAxis(0f, Vector3.up);

            for (var i = _numVerts - 1; i > 0; i--) _vertices[i] = transform.parent.position - origin;
            _lineRenderer.SetPositions(_vertices);
        }
    }
}