#pragma once

#include "CoreMinimal.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "LandscapeAuthoringLibrary.generated.h"

class ALandscape;
class ULandscapeLayerInfoObject;
class UMaterialInterface;

// One paint layer to import with the heightmap: the layer info asset the material expects and an 8-bit
// greyscale file (PNG or raw) with the same resolution as the heightmap.
USTRUCT(BlueprintType)
struct FLandscapeAuthoringWeightmap
{
	GENERATED_BODY()

	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Landscape")
	TObjectPtr<ULandscapeLayerInfoObject> LayerInfo = nullptr;

	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Landscape")
	FString File;
};

// What the editor's "New Landscape > Import" button does, callable from an authoring script. The engine exposes
// no landscape creation to Python, so this is the project's first editor tool. Mirrors
// FLandscapeEditorDetailCustomization_NewLandscape::OnCreateButtonClicked without the regions path.
UCLASS()
class SALTYEDITOR_API ULandscapeAuthoringLibrary : public UBlueprintFunctionLibrary
{
	GENERATED_BODY()

public:
	// Creates a landscape in World from a 16-bit heightmap file, centred on Location, with the given per-quad
	// scale (cm; Z is the engine's height scale where 100 spans -256 m to +256 m). The component layout is chosen
	// from the file's resolution; a file that does not fit a layout exactly is expanded, not resampled. In a
	// world-partitioned level the landscape is split into streaming proxies of GridSize x GridSize components.
	// Returns null and logs why on failure.
	UFUNCTION(BlueprintCallable, Category = "Salty|Authoring")
	static ALandscape* CreateLandscapeFromHeightmap(UWorld* World, const FString& HeightmapFile,
		const TArray<FLandscapeAuthoringWeightmap>& Weightmaps, UMaterialInterface* Material,
		FVector Location, FVector Scale, int32 WorldPartitionGridSize = 4);
};