#pragma once

// Helpers shared by the scenario files of M7 and later (the earlier files carry their own copies).

#include "CoreMinimal.h"
#include "Core/Tuning/DescentTune_Carrier.h"
#include "Debug/DescentDebugSubsystem.h"
#include "Debug/DescentScenario.h"
#include "Debug/DescentStateRegistry.h"
#include "Player/DescentCharacter.h"
#include "Player/DescentPlayerController.h"
#include "UI/DescentUiShot.h"
#include "Vehicles/DescentCarrier.h"
#include "Vehicles/KazahTender.h"
#include "TheDescent.h"

#include "Dom/JsonObject.h"
#include "Serialization/JsonSerializer.h"
#include "Serialization/JsonWriter.h"

namespace Descent::Scn
{
	inline ADescentPlayerController* PC(const FDescentScenarioContext& C) { return C.World ? Cast<ADescentPlayerController>(C.World->GetFirstPlayerController()) : nullptr; }
	inline ADescentCharacter* Char(const FDescentScenarioContext& C) { ADescentPlayerController* P = PC(C); return P ? P->GetDescentCharacter() : nullptr; }
	inline ADescentCarrier* Carrier(const FDescentScenarioContext& C) { return UDescentCarrierSubsystem::GetCarrier(C.World); }
	/** The player's feet in carrier-local metres. */
	inline FVector FeetM(const FDescentScenarioContext& C) { const ADescentCharacter* P = Char(C); const ADescentCarrier* K = Carrier(C); return (P && K) ? K->ToLocalM(P->GetFeetWorldUU()) : FVector::ZeroVector; }

	/** A screenshot with the HUD and any open window on it. */
	inline void HudShot(FDescentScenarioBuilder& S, const FString& Label)
	{
		struct FSt { int32 Phase = 0; bool bDone = false; Descent::Ui::FUiShotResult R; };
		TSharedRef<FSt> St = MakeShared<FSt>();
		S.WaitFrames(8);   // the HUD model is written at 10 Hz, the widgets read it the frame after
		S.Until(FString::Printf(TEXT("HudShot(%s)"), *Label), [St, Label](FDescentScenarioContext& C)
		{
			if (St->Phase == 0)
			{
				TSharedRef<FSt> Keep = St;
				if (!Descent::Ui::RequestUiShot(C.ScenarioName + TEXT("_") + Label, [Keep](const Descent::Ui::FUiShotResult& R) { Keep->R = R; Keep->bDone = true; }) && !St->bDone)
				{
					C.Fail(TEXT("the UI screenshot request was refused"));
					return true;
				}
				St->Phase = 1;
				return false;
			}
			if (!St->bDone) { return false; }
			if (!St->R.bOk) { C.Fail(FString::Printf(TEXT("HudShot(%s) failed: %s"), *Label, *St->R.Error)); return true; }
			UE_LOG(LogDescent, Display, TEXT("HudShot(%s): %s  %dx%d  mean luma %.3f"), *Label, *St->R.Path, St->R.Size.X, St->R.Size.Y, St->R.Stats.MeanLuma);
			return true;
		});
	}

	/** Back to the player's own view after a Camera / LookAt shot. */
	inline void ViewPlayer(FDescentScenarioBuilder& S)
	{
		S.Do(TEXT("view: the player"), [](FDescentScenarioContext& C)
		{
			ADescentPlayerController* P = PC(C);
			if (!P) { return; }
			AActor* Target = P->GetTender() ? static_cast<AActor*>(P->GetTender()) : static_cast<AActor*>(P->GetDescentCharacter());
			if (Target) { P->SetViewTarget(Target); }
		});
		S.WaitFrames(2);
	}

	/** A paused shot from a camera given in carrier-local metres. */
	inline void LocalShot(FDescentScenarioBuilder& S, const FString& Label, const FVector& CamLocalM, const FVector& LookLocalM, float Fov = 70.f)
	{
		S.Exec(TEXT("Descent.Sim.Pause 1"));
		S.Do(TEXT("camera for ") + Label, [CamLocalM, LookLocalM, Fov](FDescentScenarioContext& C)
		{
			const ADescentCarrier* K = Carrier(C);
			if (!K) { return; }
			const FVector Cam = K->ToWorldUU(CamLocalM) / 100.0, Look = K->ToWorldUU(LookLocalM) / 100.0;
			C.Debug->PlaceCamera(Cam, (Look - Cam).Rotation(), Fov);
		});
		S.Shot(Label);
		S.Exec(TEXT("Descent.Sim.Pause 0"));
		ViewPlayer(S);
	}

	/** One state section as condensed JSON text ("" if there is none). */
	inline FString SectionText(UWorld* World, const TCHAR* Section)
	{
		const TSharedRef<FJsonObject> Snap = FDescentStateRegistry::Get().BuildSnapshot(World, TEXT("probe"));
		const TSharedPtr<FJsonObject>* Obj = nullptr;
		FString Out;
		if (Snap->TryGetObjectField(FStringView(Section), Obj) && Obj && Obj->IsValid())
		{
			const TSharedRef<TJsonWriter<TCHAR, TCondensedJsonPrintPolicy<TCHAR>>> Writer = TJsonWriterFactory<TCHAR, TCondensedJsonPrintPolicy<TCHAR>>::Create(&Out);
			FJsonSerializer::Serialize(Obj->ToSharedRef(), Writer);
		}
		return Out;
	}
	/** A number of a section, e.g. ("terrain", "chunks_modified"). NaN if missing. */
	inline double SectionNumber(UWorld* World, const TCHAR* Section, const TCHAR* Field)
	{
		const TSharedRef<FJsonObject> Snap = FDescentStateRegistry::Get().BuildSnapshot(World, TEXT("probe"));
		const TSharedPtr<FJsonObject>* Obj = nullptr;
		double V = NAN;
		if (Snap->TryGetObjectField(FStringView(Section), Obj) && Obj && Obj->IsValid()) { (*Obj)->TryGetNumberField(FStringView(Field), V); }
		return V;
	}
}