#pragma once

#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "DescentTerrainActor.generated.h"

class UProceduralMeshComponent;
class UMaterialInterface;

/**
 * Owner of the pooled chunk components (DESIGN_UE.md sections 1.3, 2.1, 2.6). It has no logic: the terrain
 * subsystem hands a chunk its mesh by acquiring a component here and gives it back when the chunk unloads. A pool
 * entry has no collision (rock is queried through the density field), no navigation, no overlap events.
 */
UCLASS()
class THEDESCENT_API ADescentTerrainActor : public AActor
{
	GENERATED_BODY()

public:
	ADescentTerrainActor();

	virtual void BeginPlay() override;

	/** A hidden, empty component from the pool (a new one when the pool is empty), placed at the chunk origin. */
	UProceduralMeshComponent* AcquireChunkComponent(const FVector& OriginUU);
	/** Empties the component and puts it back in the pool. */
	void ReleaseChunkComponent(UProceduralMeshComponent* Comp);

	int32 NumActive() const { return NumActiveComps; }
	int32 NumPooled() const { return Pool.Num(); }

	/** The material every chunk uses: /Game/Materials/MI_Terrain, else M_Terrain, else the engine default (logged once). */
	UMaterialInterface* GetTerrainMaterial() const { return TerrainMaterial; }
	void SetTerrainMaterial(UMaterialInterface* Material);

private:
	UPROPERTY()
	TObjectPtr<UMaterialInterface> TerrainMaterial;

	UPROPERTY()
	TArray<TObjectPtr<UProceduralMeshComponent>> Pool;

	UPROPERTY()
	TArray<TObjectPtr<UProceduralMeshComponent>> AllComps;

	int32 NumActiveComps = 0;
};