// Copyright 1998-2017 Epic Games, Inc. All Rights Reserved.

#include "MessageLogModule.h"
#include "Logging/IMessageLog.h"
#include "IMessageLogListing.h"
#include "Modules/ModuleManager.h"
#include "Widgets/DeclarativeSyntaxSupport.h"
#include "Widgets/SWidget.h"
#include "Framework/Application/SlateApplication.h"
#include "Textures/SlateIcon.h"
#include "Framework/Docking/TabManager.h"
#include "EditorStyleSet.h"
#include "Widgets/Docking/SDockTab.h"
#include "UserInterface/SMessageLog.h"
#include "Model/MessageLogListingModel.h"
#include "Presentation/MessageLogListingViewModel.h"
#include "UserInterface/SMessageLogListing.h"
#include "Model/MessageLogModel.h"
#include "Presentation/MessageLogViewModel.h"
#include "Logging/MessageLog.h"

#if WITH_EDITOR
	#include "Editor/WorkspaceMenuStructure/Public/WorkspaceMenuStructure.h"
	#include "Editor/WorkspaceMenuStructure/Public/WorkspaceMenuStructureModule.h"
#endif

IMPLEMENT_MODULE( FMessageLogModule, MessageLog );

TSharedRef<SDockTab> SpawnMessageLog( const FSpawnTabArgs& Args, TSharedRef<FMessageLogViewModel> MessageLogViewModel )
{
	return SNew(SDockTab)
		.TabRole(ETabRole::NomadTab)
		[
			SNew(SMessageLog, MessageLogViewModel)
		];
}

static TSharedRef<IMessageLog> GetLog(const FName& LogName)
{
	FMessageLogModule& MessageLogModule = FModuleManager::LoadModuleChecked<FMessageLogModule>("MessageLog");
	return MessageLogModule.GetLogListing(LogName);
}

FMessageLogModule::FMessageLogModule()
	: bCanDisplayMessageLog(false)
{
}

void FMessageLogModule::StartupModule()
{
	MessageLogViewModel = MakeShareable(new FMessageLogViewModel(MakeShareable(new FMessageLogModel())));
	MessageLogViewModel->Initialize();

#if WITH_EDITOR
	TWeakPtr<FMessageLogViewModel> WeakMessageLogViewModel = MessageLogViewModel;
	ModulesChangedHandle = FModuleManager::Get().OnModulesChanged().AddLambda(
	[WeakMessageLogViewModel](FName InModuleName, EModuleChangeReason InReason)
	{
		if (InReason == EModuleChangeReason::ModuleLoaded && InModuleName == "LevelEditor")
		{
			FGlobalTabmanager::Get()->RegisterNomadTabSpawner("MessageLog", FOnSpawnTab::CreateStatic(&SpawnMessageLog, WeakMessageLogViewModel.Pin().ToSharedRef()))
				.SetDisplayName(NSLOCTEXT("UnrealEditor", "MessageLogTab", "Message Log"))
				.SetTooltipText(NSLOCTEXT("UnrealEditor", "MessageLogTooltipText", "Open the Message Log tab."))
				.SetGroup(WorkspaceMenu::GetMenuStructure().GetDeveloperToolsLogCategory())
				.SetIcon(FSlateIcon(FEditorStyle::GetStyleSetName(), "MessageLog.TabIcon"));
		}
	});
#endif

	// Bind us so message log output is routed via this module
	FMessageLog::OnGetLog().BindStatic(&GetLog);
}

void FMessageLogModule::ShutdownModule()
{
#if WITH_EDITOR
	if (FSlateApplication::IsInitialized())
	{
		FGlobalTabmanager::Get()->UnregisterNomadTabSpawner("MessageLog");
	}
	FModuleManager::Get().OnModulesChanged().Remove(ModulesChangedHandle);
#endif

	FMessageLog::OnGetLog().Unbind();
}

TSharedRef<IMessageLogListing> FMessageLogModule::GetLogListing(const FName& LogName)
{
	return MessageLogViewModel->GetLogListingViewModel(LogName);
}

void FMessageLogModule::RegisterLogListing(const FName& LogName, const FText& LogLabel, const FMessageLogInitializationOptions& InitializationOptions)
{
	MessageLogViewModel->RegisterLogListingViewModel(LogName, LogLabel, InitializationOptions);
}

bool FMessageLogModule::UnregisterLogListing(const FName& LogName)
{
	return MessageLogViewModel->UnregisterLogListingViewModel(LogName);
}	

bool FMessageLogModule::IsRegisteredLogListing(const FName& LogName) const
{
	return MessageLogViewModel->IsRegisteredLogListingViewModel(LogName);
}

TSharedRef<IMessageLogListing> FMessageLogModule::CreateLogListing(const FName& InLogName, const FMessageLogInitializationOptions& InitializationOptions)
{
	TSharedRef<FMessageLogListingModel> MessageLogListingModel = FMessageLogListingModel::Create( InLogName );
	return FMessageLogListingViewModel::Create( MessageLogListingModel, FText(), InitializationOptions );
}

TSharedRef<SWidget> FMessageLogModule::CreateLogListingWidget(const TSharedRef<IMessageLogListing>& InMessageLogListing)
{
	return SNew(SMessageLogListing, InMessageLogListing);
}

void FMessageLogModule::OpenMessageLog(const FName& LogName)
{
	// only open the message log if we have a window created for the tab manager & our delegate allows it
	if(bCanDisplayMessageLog
#if !PLATFORM_MAC
	   && FGlobalTabmanager::Get()->GetRootWindow().IsValid()
#endif
	   )
	{
		FGlobalTabmanager::Get()->InvokeTab(FName("MessageLog"));
		MessageLogViewModel->ChangeCurrentListingViewModel(LogName);
	}
}

void FMessageLogModule::EnableMessageLogDisplay(bool bInCanDisplayMessageLog)
{
	bCanDisplayMessageLog = bInCanDisplayMessageLog;
}