#include "ReadLuaValues.h"

#include "BlueprintActionDatabaseRegistrar.h"
#include "BlueprintNodeSpawner.h"
#include "EdGraphSchema_K2.h"
#include "K2Node_CallFunction.h"
#include "KismetCompiler.h"
#include "LuaCall.h"

#define LOCTEXT_NAMESPACE "ReadLuaValues"

const FName UK2Node_ReadLuaValues::PrototypePinName(TEXT("Prototype"));
const FName UK2Node_ReadLuaValues::InputValuesPinName(TEXT("Input Values"));
const FName UK2Node_ReadLuaValues::RemainingPinName(TEXT("Remaining"));
const FName UK2Node_ReadLuaValues::ErrorPinName(TEXT("Error"));

FText UK2Node_ReadLuaValues::GetTooltipText() const
{
	static FText Tooltip = FText::FromString(FString::Printf(TEXT(
		"Read typed values from a Lua Values array.\n"
		"\n"
		"The value prototype must be a hardwired string listing the\n"
		"types and names of the values to read, for example:\n"
		"\n"
		"  string x, float y, int z\n"
		"\n"
		"If you add '...' at the end, any remaining values will\n"
		"be available through the Remaining output pin.\n"
		"\n"
		"Supported types: %s\n"),
		*UlxLuaCallLibrary::AllKnownReturnValueTypes()));
	return Tooltip;
}

void UK2Node_ReadLuaValues::ReconstructNode()
{
	// Save the value of the Prototype Pin before it gets reconstructed.
	UEdGraphPin* PrototypePin = FindPin(PrototypePinName);
	if (PrototypePin != nullptr)
	{
		ValuePrototype = PrototypePin->DefaultValue;
	}

	Super::ReconstructNode();
}

void UK2Node_ReadLuaValues::AllocateDefaultPins()
{
	Pins.Reset();
	Super::AllocateDefaultPins();

	// Parse the value prototype string.
	FlxParsedProto ParsedProto = FlxParsedProto::ParseReturnValuesOnly(ValuePrototype);
	if (!ParsedProto.ErrorMessage.IsEmpty())
	{
		SetErrorMsg(FString::Printf(TEXT("Syntax error in value prototype: %s"), *ParsedProto.ErrorMessage));
	}

	CreatePin(EGPD_Input, UEdGraphSchema_K2::PC_Exec, UEdGraphSchema_K2::PN_Execute);
	CreatePin(EGPD_Output, UEdGraphSchema_K2::PC_Exec, UEdGraphSchema_K2::PN_Then);
	CreatePin(EGPD_Output, UEdGraphSchema_K2::PC_Exec, ErrorPinName);

	UEdGraphPin *PrototypePin = CreatePin(EGPD_Input, UEdGraphSchema_K2::PC_String, PrototypePinName);
	PrototypePin->DefaultValue = ValuePrototype;

	CreatePin(EGPD_Input, UEdGraphSchema_K2::PC_Object, UlxLuaValues::StaticClass(), InputValuesPinName);

	// Create output pins for each value.
	for (const FlxParsedProto::Pin & Pin : ParsedProto.ReturnValues)
	{
		FName PrefixedName = AddPrefix(Pin.Name, 'R');
		UFunction *Accessor = UlxLuaCallLibrary::GetReturnValueUnpacker(Pin.Type);
		if (Accessor == nullptr) {
			SetErrorMsg(FString::Printf(TEXT("Unknown value type: %s"), *Pin.Type));
			continue;
		}
		CreatePin(EGPD_Output, PropertyToPinType(Accessor->FindPropertyByName(TEXT("Result"))), PrefixedName);
	}

	if (ParsedProto.ExtraReturnValues)
	{
		CreatePin(EGPD_Output, UEdGraphSchema_K2::PC_Object, UlxLuaValues::StaticClass(), RemainingPinName);
	}
}


FText UK2Node_ReadLuaValues::GetNodeTitle(ENodeTitleType::Type TitleType) const
{
	return LOCTEXT("ReadLuaValues_Title", "Read Lua Values");
}

FText UK2Node_ReadLuaValues::GetPinDisplayName(const UEdGraphPin* Pin) const
{
	// These pins don't need labels.
	if ((Pin->PinName == UEdGraphSchema_K2::PN_Execute) ||
		(Pin->PinName == UEdGraphSchema_K2::PN_Then) ||
		(Pin->PinName == PrototypePinName))
	{
		return FText::GetEmpty();
	}

	// Return the pin name, removing R: prefix if present.
	return FText::FromName(RemovePrefix(Pin->PinName));
}

void UK2Node_ReadLuaValues::PinDefaultValueChanged(UEdGraphPin* Pin)
{
	if ((Pin->PinName == PrototypePinName) && (Pin->DefaultValue != ValuePrototype))
	{
		ReconstructNode();
	}
}


void UK2Node_ReadLuaValues::ExpandNode(class FKismetCompilerContext& CompilerContext, UEdGraph* SourceGraph)
{
	Super::ExpandNode(CompilerContext, SourceGraph);

	FlxParsedProto ParsedProto = FlxParsedProto::ParseReturnValuesOnly(ValuePrototype);
	UEdGraphPin *InputInputValuesCopyPin = FindPinChecked(InputValuesPinName);

	// Save the cursor so we can restore it on error.
	// SaveCursor returns the UlxLuaValues*, which we use as the
	// intermediate pin for all subsequent nodes.
	UFunction *SaveCursorFunc = UlxLuaValues::StaticClass()->FindFunctionByName(TEXT("SaveCursor"));
	UK2Node_CallFunction *SaveCursorNode = MakeCallFunctionNode(CompilerContext, SourceGraph, SaveCursorFunc);
	CompilerContext.MovePinLinksToIntermediate(*InputInputValuesCopyPin, *SaveCursorNode->FindPinChecked(UEdGraphSchema_K2::PN_Self));
	CompilerContext.MovePinLinksToIntermediate(*GetExecPin(), *SaveCursorNode->GetExecPin());
	UEdGraphPin *InputValuesCopyPin = SaveCursorNode->GetReturnValuePin();
	UEdGraphPin *ThenPin = SaveCursorNode->GetThenPin();

	// The Read functions automatically restore the cursor on failure,
	// so we just need a pin to wire WrongType outputs to.
	UEdGraphPin *ErrorExecPin = FindPinChecked(ErrorPinName);

	// Add Unpacking operations for all output pins.
	for (const FlxParsedProto::Pin &PinInfo : ParsedProto.ReturnValues)
	{
		UEdGraphPin *Pin = FindPinChecked(AddPrefix(PinInfo.Name, 'R'));
		UFunction *UnpackingFunc = UlxLuaCallLibrary::GetReturnValueUnpacker(PinInfo.Type);
		if (UnpackingFunc == nullptr)
		{
			CompilerContext.MessageLog.Error(TEXT("All value pins must have known types."));
			continue;
		}
		UK2Node_CallFunction *UnpackNode = MakeCallFunctionNode(CompilerContext, SourceGraph, UnpackingFunc);
		InputValuesCopyPin->MakeLinkTo(UnpackNode->FindPinChecked(UEdGraphSchema_K2::PN_Self));
		CompilerContext.CopyPinLinksToIntermediate(*ErrorExecPin, *UnpackNode->FindPinChecked(TEXT("WrongType")));
		CompilerContext.MovePinLinksToIntermediate(*Pin, *UnpackNode->FindPinChecked(TEXT("Result")));
		ThenPin = ChainExecPin(ThenPin, UnpackNode, TEXT("Success"));
	}

	// If there is a Remaining output pin, pass through the LuaValues object.
	// The cursor is already past the consumed values.
	if (ParsedProto.ExtraReturnValues)
	{
		UEdGraphPin *RemainingPin = FindPinChecked(RemainingPinName);
		CompilerContext.MovePinLinksToIntermediate(*RemainingPin, *InputValuesCopyPin);
	}

	// Link up the output exec pin.
	CompilerContext.MovePinLinksToIntermediate(*GetThenPin(), *ThenPin);

	BreakAllNodeLinks();
}


UK2Node::ERedirectType UK2Node_ReadLuaValues::DoPinsMatchForReconstruction(const UEdGraphPin* NewPin, int32 NewPinIndex, const UEdGraphPin* OldPin, int32 OldPinIndex) const
{
	if (IsTemplate() || (GetGraph() == nullptr)) return ERedirectType_None;
	if ((NewPin->PinName == OldPin->PinName) &&
		(NewPin->Direction == OldPin->Direction) &&
		(NewPin->PinType == OldPin->PinType))
	{
		return ERedirectType_Name;
	}
	return ERedirectType_None;
}

bool UK2Node_ReadLuaValues::IsConnectionDisallowed(const UEdGraphPin* MyPin, const UEdGraphPin* OtherPin, FString& OutReason) const
{
	// The prototype pin cannot be connected.
	if (MyPin->PinName == PrototypePinName)
	{
		OutReason = LOCTEXT("Error_PrototypeMustBeHardwired", "Value prototype must be a hardwired constant.").ToString();
		return true;
	}

	return Super::IsConnectionDisallowed(MyPin, OtherPin, OutReason);
}

void UK2Node_ReadLuaValues::GetMenuActions(FBlueprintActionDatabaseRegistrar& ActionRegistrar) const
{
	UClass* ActionKey = GetClass();
	if (ActionRegistrar.IsOpenForRegistration(ActionKey))
	{
		UBlueprintNodeSpawner* NodeSpawner = UBlueprintNodeSpawner::Create(GetClass());
		check(NodeSpawner != nullptr);
		ActionRegistrar.AddBlueprintAction(ActionKey, NodeSpawner);
	}
}

FText UK2Node_ReadLuaValues::GetMenuCategory() const
{
	return FText::FromString(FString(TEXT("Luprex|Lua")));
}


#undef LOCTEXT_NAMESPACE