using UnityEngine;

/*
 * <summary>A replacement for the Item class in VR contexts.</summary>
 */
[RequireComponent(typeof(Burnable))]
public class ItemVR : MonoBehaviour {
    public BurnQuality IgnitedQuality;
    public float IgniteDuration;
    public bool Ignited = false;
    public bool Extinguished = false;
    public float TorchDuration;
    public float TorchWarnDuration;
    public float MinDistanceFromTerrain;
    public float FuelTickingMultiplierOnGround;

    [Header("Burning indicators")]
    public GameObject StickObject;
    public GameObject DestroyedOnExtinguish;
    public GameObject TorchObject;
    public ParticleSystem FireParticles;
    public Light TorchLight;
    public Color WarnColor;
    public GameObject FireVolume;
    public AudioSource TorchSound;
    public AudioClip[] FireClips;

    [Header("Runtime values")]
    public float TorchFuel;

    private Burnable Burnable;
    private int BurningSourceCount = 0;
    private float IgnitionStartTime = -1;
    private Color NormalColor;

    private Terrain Terrain;
    private Vector3 TorchLightBasePosition;

    private void Start() {
        Burnable = GetComponent<Burnable>();
        NormalColor = TorchLight.color;
        TorchObject.SetActive(Ignited);
        StickObject.SetActive(!Ignited);

        Terrain = GameObject.FindGameObjectWithTag("Main Terrain").GetComponent<Terrain>();
        TorchLightBasePosition = TorchLight.transform.localPosition;
    }

    private void Update() {
        if (Extinguished) {
            return;
        }

        if (Ignited) {
            float FuelTickAmount = Time.deltaTime;

            TorchLight.transform.localPosition = TorchLightBasePosition;
            Vector3 LightPosition = TorchLight.transform.position;
            float MinHeight = (Terrain.SampleHeight(LightPosition) + Terrain.transform.position.y) + MinDistanceFromTerrain;
            if (LightPosition.y < MinHeight) {
                // The light is on ground, clamp it above round (so the light doesn't look weird)
                // and start ticking fuel at a higher rate
                LightPosition.y = MinHeight;
                FuelTickAmount *= FuelTickingMultiplierOnGround;
            }
            TorchLight.transform.position = LightPosition;

            TorchFuel -= FuelTickAmount;
            if (TorchFuel < TorchWarnDuration) {
                TorchLight.color = Color.Lerp(TorchLight.color, WarnColor, 5f * Time.deltaTime);
            } else {
                TorchLight.color = Color.Lerp(TorchLight.color, NormalColor, 5f * Time.deltaTime);
            }

            if ((TorchSound.clip.length - TorchSound.time) <= Time.deltaTime || !TorchSound.isPlaying) {
                TorchSound.clip = FireClips[Random.Range(0, FireClips.Length)];
                TorchSound.time = 0;
                TorchSound.Play();
            }
            float FuelFactor = 1f / (Mathf.Max(0, TorchDuration + 0.5f - TorchFuel) * 4f + 1);
            TorchSound.volume = 0.5f + 0.5f * FuelFactor - (TorchFuel < TorchWarnDuration ? 0.1f : 0);

            if (TorchFuel <= 0) {
                FireParticles.Stop();
                FireVolume.layer = gameObject.layer;
                TorchLight.range = Mathf.Lerp(TorchLight.range, 0, 10f * Time.deltaTime);
                if (TorchLight.range < 0.01f) {
                    Destroy(DestroyedOnExtinguish);
                    Extinguished = true;
                }
            }
        } else if (!Ignited && !Burnable.BurningInCampfire && IgnitionStartTime != -1 && Time.time - IgnitionStartTime >= IgniteDuration) {
            Ignited = true;
            TorchFuel = TorchDuration;
            TorchObject.SetActive(true);
            FireParticles.Play();
            StickObject.SetActive(false);
            Burnable.Quality = IgnitedQuality;
        }
    }

    private void OnTriggerEnter(Collider collider) {
        if (!Ignited && collider.gameObject.layer == LayerMask.NameToLayer("Fire")) {
            if (BurningSourceCount == 0) {
                IgnitionStartTime = Time.time;
            }
            BurningSourceCount++;
        }
    }

    private void OnTriggerExit(Collider collider) {
        if (!Ignited && collider.gameObject.layer == LayerMask.NameToLayer("Fire")) {
            BurningSourceCount--;
            if (BurningSourceCount == 0) {
                IgnitionStartTime = -1;
            }
        }
    }
}