#pragma once

#include "CoreMinimal.h"
#include "GameFramework/PlayerController.h"
#include "Core/DescentHandle.h"
#include "Player/DescentMode.h"
#include "DescentPlayerController.generated.h"

class UInputAction;
class UInputMappingContext;
class ADescentCharacter;
class AKazahTender;
class UCarrierCarouselComponent;

/**
 * The player controller (DESIGN_UE.md sections 5.6, 5.7, 5.9). Enhanced Input is created here in C++ (no input assets): handlers only
 * record which keys are down and how far the mouse moved; every frame the controller turns that into an FDescentIntent and hands it to the
 * sim, which latches it. One-shot keys (E, F, Space in the cradle, Tab, M, Esc) call the mode actions below; the debug commands call the
 * same actions, so a test and a player go through one path.
 *
 * Modes at M3: Title, Foot, Board, Docked, Launch, Sub, Dock, Swim, Ladder, Dead. The timed ones are advanced in the sim (step 3, after
 * the carousel). The UI overlay is a flag on top of the mode: while a window is open or the game is paused, move and look are ignored.
 * (DescentPlayerController.cpp: input, intent, HUD model, boot, state. DescentPlayerModes.cpp: the mode state machine.)
 */
UCLASS()
class THEDESCENT_API ADescentPlayerController : public APlayerController
{
	GENERATED_BODY()

public:
	ADescentPlayerController();

	virtual void SetupInputComponent() override;
	virtual void BeginPlay() override;
	virtual void EndPlay(const EEndPlayReason::Type Reason) override;
	virtual void PlayerTick(float DeltaTime) override;

	EDescentMode GetMode() const { return Mode; }
	void SetMode(EDescentMode NewMode);
	/** True while a UI window is open (PDA, map, pause, title, a station): game input is ignored. */
	bool IsUiOpen() const;
	/** Every mode entered since the start, oldest first (scenarios assert the sequence). */
	const TArray<EDescentMode>& GetModeHistory() const { return ModeHistory; }
	void ClearModeHistory() { ModeHistory.Reset(); ModeHistory.Add(Mode); }

	/** Section 5.9: the point every depth, compass and temperature readout uses. Metres, world. */
	FVector RefPointM() const;

	ADescentCharacter* GetDescentCharacter() const;
	/** The Tender the player sits in or flies (Board .. Dock), or null. */
	AKazahTender* GetTender() const { return Tender.Get(); }
	UCarrierCarouselComponent* GetCarousel() const;

	// ---- mode actions: keys and debug commands share them. False and a reason when refused. ----
	/** Foot -> Board (1.4 s) -> Docked. The Tender must hang at BOARD. */
	bool BeginBoard(AKazahTender* T, FString* OutWhyNot = nullptr);
	/** Docked -> Launch (3.2 s) -> Sub. */
	bool Launch(FString* OutWhyNot = nullptr);
	/** Sub -> Dock (4.2 s) -> Docked. Only under the moon pool. */
	bool Dock(FString* OutWhyNot = nullptr);
	/** Docked -> Foot at the pool rim. */
	bool LeaveDocked(FString* OutWhyNot = nullptr);
	/** Sub -> Swim: the roof hatch opens, the swimmer appears beside the Tender. */
	bool ExitToSwim(FString* OutWhyNot = nullptr);
	/** Swim -> Sub: into a Tender that is out, within 4.5 m (bIgnoreRange: debug). */
	bool EnterTender(AKazahTender* T, bool bIgnoreRange = false, FString* OutWhyNot = nullptr);
	/** Foot -> Swim where the body is (or at a world position, debug). */
	bool EnterSwim(const FVector* WorldUU = nullptr);
	/** Foot -> Swim in the moon pool (E at the ladder sign, Descent.Player.PoolDrop). */
	bool PoolDrop(FString* OutWhyNot = nullptr);
	/** Swim -> Ladder (1.6 s) -> Foot at the pool rim. bIgnoreRange: debug. */
	bool Climb(bool bIgnoreRange = false, FString* OutWhyNot = nullptr);
	bool CanClimb() const;
	/** The Tender a swimmer could enter right now (out, within 4.5 m), or null. */
	AKazahTender* FindEnterableTender() const;
	/** Foot -E helm-> Helm; E again (or LeaveHelm) -> Foot, and the carrier comes to an all stop. */
	bool EnterHelm(FString* OutWhyNot = nullptr);
	bool LeaveHelm();
	/** E. */
	void PressUse();
	/** LMB or G on foot with a box in the hands: puts it down (section 5.5). */
	void PutDownCarried();
	/** F. */
	void ToggleLight();
	/** The vitals report a death (drown), or the piloted Tender imploded: fade, 2.6 s, respawn in the galley. */
	void OnPlayerDied();
	/** The body was put on a deck by a command or a respawn: the mode follows. */
	void OnPlacedOnFoot();
	/** Tab, M, Esc / P / H: opens the window over the current mode (not in Title or Dead). */
	bool OpenUi(const FString& WindowName);

private:
	struct FKeys
	{
		bool Forward = false, Back = false, Left = false, Right = false, Jump = false, Down = false, Sprint = false, Primary = false, Secondary = false, Use = false, Alt = false;
		bool LookLeft = false, LookRight = false, LookUp = false, LookDown = false;
		FVector2D Mouse = FVector2D::ZeroVector;   // accumulated this frame, counts
	};
	/** Heap state shared with the input lambdas (the controller owns it). */
	TSharedRef<FKeys> Keys = MakeShared<FKeys>();

	void BindKey(class UEnhancedInputComponent* EIC, UInputMappingContext* Ctx, const FKey& Key, bool FKeys::* Member);
	void BindPress(class UEnhancedInputComponent* EIC, UInputMappingContext* Ctx, const FKey& Key, TFunction<void()> Fn);
	void WriteHudModel();
	void UpdateFocus();
	void StepModes(double Dt);
	void Respawn();
	void SeatIn(AKazahTender* T, float BlendSeconds);
	void Unseat();
	FString UsePrompt() const;

	EDescentMode Mode = EDescentMode::Title;
	TArray<EDescentMode> ModeHistory;
	FDescentHandle FocusStep, HudStep, ModeStep;

	TWeakObjectPtr<AKazahTender> Tender;
	double ModeTime = 0.0;              // sim seconds in the current mode
	bool bBoardViewStarted = false;
	bool bDeadByImplosion = false;
	TWeakObjectPtr<AKazahTender> LidTender;   // a lid that was opened and closes again after LidTimer
	double LidTimer = 0.0;
	// M7: E on a placed object is a short press (use it) or a 0.8 s hold (pick it up)
	TWeakObjectPtr<UObject> UseHoldTarget;
	double UseHoldTime = 0.0;

	UPROPERTY(Transient) TObjectPtr<UInputMappingContext> MappingContext;
	UPROPERTY(Transient) TArray<TObjectPtr<UInputAction>> Actions;
};