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

public class MarsEffects : MonoBehaviour
{
    [Header("Οθλ")]
    public Material dustMaterial;
    public float planetRadius = 6.779f;

    [Range(0f, 1f)]
    public float troposphereLevel = 1f;
    public float previousLevel = 1f;

    private List<ParticleSystem> dustClusters = new List<ParticleSystem>();
    private Light nightLight;
    private bool initialized = false;

    private const int DUST_COUNT = 20;

    void Awake()
    {
        enabled = false;
    }

    public void InitState()
    {
        foreach (var ps in dustClusters)
            if (ps != null) Destroy(ps.gameObject);
        dustClusters.Clear();

        if (nightLight != null)
        {
            Destroy(nightLight.gameObject);
            nightLight = null;
        }

        troposphereLevel = 1f;
        previousLevel = 1f;
        initialized = false;

        CreateDustSystem();
        CreateNightLight();
        initialized = true;
    }

    void CreateDustSystem()
    {
        for (int i = 0; i < DUST_COUNT; i++)
        {
            Vector3 dir = Random.onUnitSphere;
            Vector3 pos = transform.position + dir * (planetRadius + Random.Range(0.5f, 2f));

            GameObject obj = new GameObject("DustCluster_" + i);
            obj.transform.parent = null;
            obj.transform.position = pos;

            ParticleSystem ps = obj.AddComponent<ParticleSystem>();

            var main = ps.main;
            main.loop = true;
            main.playOnAwake = true;
            main.maxParticles = 200;
            main.startLifetime = new ParticleSystem.MinMaxCurve(5f, 12f);
            main.startSpeed = new ParticleSystem.MinMaxCurve(0f, 0.5f);
            main.startSize = new ParticleSystem.MinMaxCurve(0.1f, 0.4f);
            main.startColor = new ParticleSystem.MinMaxGradient(
                new Color(0.9f, 0.5f, 0.2f, 0.5f),
                new Color(0.7f, 0.35f, 0.1f, 0.3f)
            );
            main.simulationSpace = ParticleSystemSimulationSpace.World;
            main.gravityModifier = 0f;

            var emission = ps.emission;
            emission.rateOverTime = 20f;

            var shape = ps.shape;
            shape.enabled = true;
            shape.shapeType = ParticleSystemShapeType.Sphere;
            shape.radius = 1.5f;
            shape.radiusThickness = 1f;

            var colorOverLifetime = ps.colorOverLifetime;
            colorOverLifetime.enabled = true;
            Gradient gradient = new Gradient();
            gradient.SetKeys(
                new GradientColorKey[] {
                    new GradientColorKey(new Color(0.9f, 0.5f, 0.2f), 0f),
                    new GradientColorKey(new Color(0.7f, 0.35f, 0.1f), 0.5f),
                    new GradientColorKey(new Color(0.5f, 0.25f, 0.08f), 1f)
                },
                new GradientAlphaKey[] {
                    new GradientAlphaKey(0f, 0f),
                    new GradientAlphaKey(0.5f, 0.2f),
                    new GradientAlphaKey(0.3f, 0.7f),
                    new GradientAlphaKey(0f, 1f)
                }
            );
            colorOverLifetime.color = new ParticleSystem.MinMaxGradient(gradient);

            var noise = ps.noise;
            noise.enabled = true;
            noise.strength = 0.8f;
            noise.frequency = 0.3f;
            noise.scrollSpeed = 0.2f;
            noise.octaveCount = 2;

            var renderer = ps.GetComponent<ParticleSystemRenderer>();
            renderer.renderMode = ParticleSystemRenderMode.Billboard;
            renderer.sortingFudge = 3f;
            if (dustMaterial != null)
                renderer.material = dustMaterial;

            ps.Play();
            dustClusters.Add(ps);

            StartCoroutine(OrbitDust(obj.transform, dir, planetRadius + Random.Range(0.5f, 2f)));
        }
    }

    void CreateNightLight()
    {
        GameObject lightObj = new GameObject("MarsNightLight");
        lightObj.transform.parent = null;
        lightObj.transform.position = transform.position + Vector3.right * (planetRadius * 3f);

        nightLight = lightObj.AddComponent<Light>();
        nightLight.type = LightType.Spot;
        nightLight.color = new Color(0.8f, 0.3f, 0.1f);
        nightLight.intensity = 0f;
        nightLight.range = planetRadius * 400f;
        nightLight.spotAngle = 170f;
        nightLight.shadows = LightShadows.None;

        StartCoroutine(OrbitLight(lightObj.transform));
    }


    IEnumerator OrbitDust(Transform dust, Vector3 axis, float radius)
    {
        Vector3 orbitAxis = Vector3.Cross(axis, Random.onUnitSphere).normalized;
        float speed = Random.Range(1f, 4f);
        float wobbleSpeed = Random.Range(0.1f, 0.3f);
        float wobbleAmount = Random.Range(0.1f, 0.3f);

        while (dust != null)
        {
            dust.RotateAround(transform.position, orbitAxis, speed * Time.deltaTime);
            float wobble = Mathf.Sin(Time.time * wobbleSpeed) * wobbleAmount;
            dust.position = transform.position +
                (dust.position - transform.position).normalized * (radius + wobble);
            yield return null;
        }
    }

    void UpdateDust()
    {
        float level = troposphereLevel;

        foreach (var ps in dustClusters)
        {
            if (ps == null) continue;

            var emission = ps.emission;
            var main = ps.main;

            if (level >= 0.7f)
            {
                float t = Mathf.InverseLerp(1f, 0.7f, level);
                emission.rateOverTime = Mathf.Lerp(20f, 12f, t);
                main.startColor = new ParticleSystem.MinMaxGradient(
                    new Color(0.9f, 0.5f, 0.2f, Mathf.Lerp(0.5f, 0.35f, t)),
                    new Color(0.7f, 0.35f, 0.1f, Mathf.Lerp(0.3f, 0.2f, t))
                );
            }
            else if (level >= 0.5f)
            {
                float t = Mathf.InverseLerp(0.7f, 0.5f, level);
                emission.rateOverTime = Mathf.Lerp(12f, 5f, t);
                main.startColor = new ParticleSystem.MinMaxGradient(
                    new Color(0.9f, 0.5f, 0.2f, Mathf.Lerp(0.35f, 0.15f, t)),
                    new Color(0.7f, 0.35f, 0.1f, Mathf.Lerp(0.2f, 0.08f, t))
                );
            }
            else if (level >= 0.3f)
            {
                float t = Mathf.InverseLerp(0.5f, 0.3f, level);
                emission.rateOverTime = Mathf.Lerp(5f, 1f, t);
                main.startColor = new ParticleSystem.MinMaxGradient(
                    new Color(0.9f, 0.5f, 0.2f, Mathf.Lerp(0.15f, 0.03f, t)),
                    new Color(0.7f, 0.35f, 0.1f, Mathf.Lerp(0.08f, 0.01f, t))
                );
            }
            else
            {
                emission.rateOverTime = 0f;
            }
        }
    }


    void UpdateNightLight()
    {
        if (nightLight == null) return;

        if (troposphereLevel >= 1f)
            nightLight.intensity = 0f;
        else if (troposphereLevel >= 0.7f)
            nightLight.intensity = Mathf.Lerp(200f, 400f, Mathf.InverseLerp(1f, 0.7f, troposphereLevel));
        else if (troposphereLevel >= 0.5f)
            nightLight.intensity = Mathf.Lerp(400f, 450f, Mathf.InverseLerp(0.7f, 0.5f, troposphereLevel));
        else if (troposphereLevel >= 0.3f)
            nightLight.intensity = Mathf.Lerp(450f, 500f, Mathf.InverseLerp(0.5f, 0.3f, troposphereLevel));
        else
            nightLight.intensity = Mathf.Lerp(500f, 600f, Mathf.InverseLerp(0.3f, 0f, troposphereLevel));
    }

IEnumerator OrbitLight(Transform lightTransform)
{
    float angle = 0f;
    float speed = 60f;

    while (lightTransform != null && nightLight != null)
    {
        angle += speed * Time.deltaTime;
        float rad = angle * Mathf.Deg2Rad;
        lightTransform.position = transform.position +
            new Vector3(Mathf.Cos(rad), 0.3f, Mathf.Sin(rad)) * (planetRadius * 3f);
        lightTransform.LookAt(transform.position);
        nightLight.range = planetRadius * 400f;
        nightLight.spotAngle = 170f;
        yield return null;
    }
}

    void Update()
    {
        if (!Application.isPlaying) return;

        if (troposphereLevel >= 1f && previousLevel < 1f)
            InitState();

        previousLevel = troposphereLevel;
        UpdateDust();
        UpdateNightLight();
    }

    public void CleanUp()
    {
        foreach (var ps in dustClusters)
            if (ps != null) Destroy(ps.gameObject);
        dustClusters.Clear();

        if (nightLight != null)
        {
            Destroy(nightLight.gameObject);
            nightLight = null;
        }

        enabled = false;
    }
}