using System;
using Sandbox;
using Sandbox.ui;

public sealed class SceneGrassComponent : Component
{
    public static bool EditorPainterActive { get; set; }

	public GrassRenderObject Renderer { get; private set; }

	[Property] public GrassDensityMapResource DensityMapResource { get; set; }

	[Property] public float ChunkSize { get; set; } = 256.0f;

	[Property] public int ChunkResolution { get; set; } = 64;

	[Property] public int RenderRadius { get; set; } = 6;

	[Property] public float StreamingRadius { get; set; } = 1536.0f;

	[Property] public float LodCutoff { get; set; } = 2048.0f;

	[Property] public float DistanceCutoff { get; set; } = 4096.0f;

	[Property] public float LodTransitionRange { get; set; } = 200.0f;

	[Property] public float DistanceTransitionRange { get; set; } = 200.0f;

	[Property] public float DisplacementStrength { get; set; } = 200.0f;

	[Property] public float TerrainProbeTop { get; set; } = 4096.0f;

	[Property] public float TerrainProbeBottom { get; set; } = -4096.0f;

	[Property] public float TerrainHeightOffset { get; set; } = 0.0f;

	[Property] public float GrassHeightPadding { get; set; } = 128.0f;

	[Property] public float FallbackHeight { get; set; } = 0.0f;

	[Property] public float InteractionStrength { get; set; } = 8.0f;

	[Property] public float InteractionStampRate { get; set; } = 36.0f;

	[Property] public float InteractionBendHoldDuration { get; set; } = 0.5f;

	[Property] public float InteractionDecayUpdateInterval { get; set; } = 0.05f;

	[Property] public float CutDuration { get; set; } = 8.0f;

	protected override void OnAwake()
	{
		base.OnAwake();

		using ( Scene.Push() )
		{
			Renderer = new GrassRenderObject( Scene.SceneWorld );

		}

		SyncRendererSettings();
	}

	private void SyncRendererSettings()
	{
		if ( Renderer == null )
			return;

		float streamingRadius = StreamingRadius;
		if ( EditorPainterActive )
			streamingRadius *= 10.0f;

		Renderer.ChunkSize = ChunkSize;
		Renderer.ChunkResolution = ChunkResolution;
		float requiredStreamingRadius = Math.Max( streamingRadius, Math.Max( LodCutoff, DistanceCutoff ) + ChunkSize );
		Renderer.RenderRadius = Math.Max( 1, MathX.CeilToInt( requiredStreamingRadius / Math.Max( ChunkSize, 0.001f ) ) );
		Renderer.LodCutoff = LodCutoff;
		Renderer.LodTransitionRange = LodTransitionRange;
		Renderer.DistanceTransitionRange = DistanceTransitionRange;
		Renderer.DistanceCutoff = DistanceCutoff;
		Renderer.DisplacementStrength = DisplacementStrength;
		Renderer.TerrainProbeTop = TerrainProbeTop;
		Renderer.TerrainProbeBottom = TerrainProbeBottom;
		Renderer.TerrainHeightOffset = TerrainHeightOffset;
		Renderer.GrassHeightPadding = GrassHeightPadding;
		Renderer.FallbackHeight = FallbackHeight;
		Renderer.InteractionStrength = InteractionStrength;
		Renderer.InteractionStampRate = InteractionStampRate;
		Renderer.InteractionBendHoldDuration = InteractionBendHoldDuration;
		Renderer.CutDuration = CutDuration;
		Renderer.InteractionDecayUpdateInterval = InteractionDecayUpdateInterval;
		Renderer.SetDensityResource( DensityMapResource );
		Renderer.CullingCamera = Scene.Camera;
}

	protected override void OnUpdate()
	{
		base.OnUpdate();

		UpdateRenderer();

	}

	private void UpdateRenderer()
	{
		if ( Renderer == null )
			return;

		if ( Scene.Camera == null )
			return;

		SyncRendererSettings();
		Renderer.SetDensityResource( DensityMapResource );
		Renderer.CullingCamera = Scene.Camera;
		Renderer.UpdateInteractionField( Scene.GetAllComponents<GrassInteractionSourceComponent>(), Time.Delta );

		Vector3 camPos = Scene.Camera.WorldPosition;

		Renderer.UpdateStreaming( camPos );

		Renderer.ProcessPendingDestroy();
	}

	protected override void OnDisabled()
	{
		base.OnDisabled();

		Renderer?.Disable();

		Renderer = null;
	}

	protected override void DrawGizmos()
	{
		base.DrawGizmos();

		UpdateRenderer();

		if ( !EditorPainterActive )
			return;

		if ( Renderer == null )
			return;

		Gizmo.Draw.Color = Color.Yellow;

		foreach ( var pair in Renderer.ActiveChunks )
		{
			BBox bounds = BBox.FromPositionAndSize( pair.Value.Bounds.Center, pair.Value.Bounds.Size.WithZ( 0 ) );
			Gizmo.Draw.LineBBox( bounds );
		}
	}
}