// Copyright 1998-2014 Epic Games, Inc. All Rights Reserved.

/*=============================================================================
	TaskDataManager.cpp: Data management layer between task GUI system and database connection
=============================================================================*/

#include "TaskBrowserPrivatePCH.h"
#include "TaskDataManager.h"
#include "TaskDatabase.h"

/**
 * FTaskDataManager constructor
 *
 * @param	InGUICallbackObject		Object that we'll call back to for GUI interop
 */
FTaskDataManager::FTaskDataManager( FTaskDataGUIInterface* InGUICallbackObject )
	: GUICallbackObject( InGUICallbackObject ),
	  ConnectionSettings(),
	  UserRealName(),
	  ResolutionValues(),
	  OpenTaskStatusPrefix(),
	  ConnectionStatus( ETaskDataManagerStatus::Unknown ),
	  QueryStatus( ETaskDataManagerStatus::Unknown ),
	  bShouldRefreshFilterNames( false ),
	  ActiveFilterName(),
	  FocusedTaskNumber( INDEX_NONE ),
	  TaskNumbersToMarkComplete(),
	  ResolutionData(),
	  CurrentlyProcessingTaskNumber( INDEX_NONE ),
	  CachedFilterNames(),
	  CachedTaskArray(),
	  CachedLastTaskArrayFilterName(),
	  CachedTaskDetailsMap()
{
	// Initialize the task database system if we need to
	if( !TaskDatabaseSystem::IsInitialized() )
	{
		// Initialize task database
		if( !TaskDatabaseSystem::Init() )
		{
			// Failed to init task database.  Oh well, these features simply won't be available here on out.
			ConnectionStatus = ETaskDataManagerStatus::FailedToInit;
		}
	}

	if( TaskDatabaseSystem::IsInitialized() )
	{
		// Register as a listener
		TaskDatabaseSystem::RegisterListener( this );

		// Task database was initialized successfully.  We're ready to connect now!
		ConnectionStatus = ETaskDataManagerStatus::ReadyToConnect;
	}
}



/** FTaskDataManager destructor */
FTaskDataManager::~FTaskDataManager()
{
	if( TaskDatabaseSystem::IsInitialized() )
	{
		// Unregister as a listener
		TaskDatabaseSystem::UnregisterListener( this );

		// Shutdown the task database.  This may take a few moments as we wait for the user to be logged
		// out from the server and the threads to join.
		TaskDatabaseSystem::Destroy();
	}
}



/**
 * Called from within LevelTick.cpp after ticking all actors or from
 * the rendering thread (depending on bIsRenderingThreadObject)
 *
 * @param DeltaTime	Game time passed since the last call.
 */
void FTaskDataManager::Tick( float DeltaTime )
{
	// Update self
	UpdateTaskDataManager();

	if( TaskDatabaseSystem::IsInitialized() )
	{
		// Update the task database.  This may fire off events after server responses are received.
		TaskDatabaseSystem::Update();
	}
}

TStatId FTaskDataManager::GetStatId() const
{
	RETURN_QUICK_DECLARE_CYCLE_STAT(FTaskDataManager, STATGROUP_Tickables);
}


/**
 * Starts process of marking the specified task numbers as completed
 *
 * @param	InTaskNumbers		Numbers of tasks to mark as completed
 * @param	InResolutionData	User-entered resolution data for these tasks
 */
void FTaskDataManager::StartMarkingTasksComplete( const TArray< uint32 >& InTaskNumbers,
												  const FTaskResolutionData& InResolutionData )
{
	// Add the specified tasks to our list of tasks to complete.  We'll process these when we have time to.
	for( int32 CurTaskIndex = 0; CurTaskIndex < InTaskNumbers.Num(); ++CurTaskIndex )
	{
		TaskNumbersToMarkComplete.AddUnique( InTaskNumbers[ CurTaskIndex ] );
	}

	// @todo: It's possible for resolution data to be changed here while tasks to complete are already queued

	// Store the resolution data
	ResolutionData = InResolutionData;
}




/** Initiates or re-initiates a connection to the task database server */
void FTaskDataManager::AttemptConnection()
{
	if( ConnectionStatus == ETaskDataManagerStatus::ReadyToConnect ||
		ConnectionStatus == ETaskDataManagerStatus::ConnectionFailed )
	{
		ConnectionStatus = ETaskDataManagerStatus::Connecting;
	}
}



/** Initiates a disconnection from the task database server */
void FTaskDataManager::AttemptDisconnection()
{
	if( ConnectionStatus != ETaskDataManagerStatus::FailedToInit &&
		ConnectionStatus != ETaskDataManagerStatus::ReadyToConnect &&
		ConnectionStatus != ETaskDataManagerStatus::ConnectionFailed )
	{
		ConnectionStatus = ETaskDataManagerStatus::Disconnecting;
	}
}



/** Starts a forced a refresh of task list/description data from the server */
void FTaskDataManager::ClearTaskDataAndInitiateRefresh()
{
	// @todo: Support pinging the server every so often to check for changes automatically?

	// Wipe out cached task details
	CachedTaskDetailsMap.Empty();

	// We'll clear the last filter name to force a full refresh of the task list.
	CachedLastTaskArrayFilterName = TEXT( "" );
}



/** Updates our state machine.  Should be called frequently (every Tick is OK) */
void FTaskDataManager::UpdateTaskDataManager()
{
	// If we're waiting for a request to finish, then don't bother sending new tasks
	if( TaskDatabaseSystem::IsInitialized() &&
		!TaskDatabaseSystem::IsRequestInProgress() )
	{
		if( !TaskDatabaseSystem::IsConnected() && ConnectionStatus == ETaskDataManagerStatus::Connecting )
		{
			// Go ahead and connect
			if( !TaskDatabaseSystem::ConnectToDatabase_Async(
					ConnectionSettings.ServerName,
					ConnectionSettings.ServerPort,
					ConnectionSettings.UserName,
					ConnectionSettings.Password,
					ConnectionSettings.ProjectName ) )
			{
				// Failed to initiate connection!
				ConnectionStatus = ETaskDataManagerStatus::ConnectionFailed;

				FMessageDialog::Open( EAppMsgType::Ok, NSLOCTEXT("UnrealEd", "TaskBrowser_Error_StartingConnect", "The Task Browser encountered an uncommon error while trying to connect to the database.  Please adjust your connection settings using the Settings button at the bottom of the Task Browser and try again by clicking Connect." ) );
			}
		}

		if( TaskDatabaseSystem::IsConnected() )
		{
			// If we were asked to disconnect, then do that now
			if( ConnectionStatus == ETaskDataManagerStatus::Disconnecting )
			{
				if( !TaskDatabaseSystem::DisconnectFromDatabase_Async() )
				{
					// Failed to initiate disconnection!  Should never happen, but not a big deal.
					FMessageDialog::Open( EAppMsgType::Ok, NSLOCTEXT("UnrealEd", "TaskBrowser_Error_StartingDisconnect", "The Task Browser encountered an uncommon error while trying to disconnect from the database." ) );
				}
			}


			// OK, we're connected and ready for work!
			if( bShouldRefreshFilterNames )
			{
				// Query filters
				if( TaskDatabaseSystem::QueryFilters_Async() )
				{
					QueryStatus = ETaskDataManagerStatus::QueryingFilters;
				}
				else
				{
					// Failed to initiate query for filters!  Should never happen, but not a big deal.
					FMessageDialog::Open( EAppMsgType::Ok, NSLOCTEXT("UnrealEd", "TaskBrowser_Error_StartingFilterQuery", "The Task Browser encountered an uncommon error while trying to query a list of filters from the database." ) );
				}

				bShouldRefreshFilterNames = false;
			}
			// Have we been asked to mark any tasks as completed?
			else if( TaskNumbersToMarkComplete.Num() > 0 )
			{
				// Pop the first task off the list and mark it as completed
				const uint32 TaskNumber = TaskNumbersToMarkComplete[ 0 ];
				TaskNumbersToMarkComplete.RemoveAt( 0 );

				// Keep track of the task number we're working on
				CurrentlyProcessingTaskNumber = TaskNumber;

				if( TaskDatabaseSystem::MarkTaskComplete_Async( TaskNumber, ResolutionData ) )
				{
					QueryStatus = ETaskDataManagerStatus::MarkingTaskComplete;
				}
				else
				{
					// Failed to initiate marking task as complete.  Should never happen.
					FMessageDialog::Open( EAppMsgType::Ok, NSLOCTEXT("UnrealEd", "TaskBrowser_Error_StartingMarkAsComplete", "The Task Browser encountered an uncommon error while trying to mark a task as complete." ) );
				}
			}
			else if( ActiveFilterName != CachedLastTaskArrayFilterName )	// Has filter name changed?
			{
				if( ActiveFilterName.Len() > 0 )
				{
					// Query some tasks!
					if( TaskDatabaseSystem::QueryTasks_Async( ActiveFilterName ) )
					{
						QueryStatus = ETaskDataManagerStatus::QueryingTasks;

						// Store filter name these tasks were queried with so we'll know later that the
						// tasks don't need to be retrieved again
						CachedLastTaskArrayFilterName = ActiveFilterName;
					}
					else
					{
						// Failed to initiate query for tasks!
						FMessageDialog::Open( EAppMsgType::Ok, NSLOCTEXT("UnrealEd", "TaskBrowser_Error_StartingQueryTasks", "The Task Browser encountered an uncommon error while trying to query a list of tasks." ) );
					}
				}
			}
			else
			{
				// Do we have a task number to retrieve details for?
				if( FocusedTaskNumber != INDEX_NONE )
				{
					if( FindCachedTaskDetails( FocusedTaskNumber ) == NULL )
					{
						if( TaskDatabaseSystem::QueryTaskDetails_Async( FocusedTaskNumber ) )
						{
							QueryStatus = ETaskDataManagerStatus::QueryingTaskDetails;

							// Let the GUI know that we've started downloading a task description
							if( GUICallbackObject != NULL )
							{
								GUICallbackObject->Callback_RefreshGUI(
									ETaskBrowserGUIRefreshOptions::UpdateTaskDescription );
							}
						}
						else
						{
							// Failed to initiate query for task details
							FMessageDialog::Open( EAppMsgType::Ok, NSLOCTEXT("UnrealEd", "TaskBrowser_Error_StartingQueryTaskDetails", "The Task Browser encountered an uncommon error while trying to query details about a task." ) );

							// Reset the focused task number so that we don't spam requests on error
							SetFocusedTaskNumber( INDEX_NONE );
						}
					}
				}
			}
		}
	}
}



/** We've been disconnected (either voluntarily or otherwise), so clean up state and refresh GUI */
void FTaskDataManager::CleanUpAfterDisconnect()
{
	// Clear filter names
	CachedFilterNames.Empty();

	// Clear task entry array
	CachedTaskArray.Empty();

	// Wipe out cached task details
	CachedTaskDetailsMap.Empty();

	// No longer focused on any task
	FocusedTaskNumber = INDEX_NONE;

	// Cancel any requests to mark tasks as completed
	TaskNumbersToMarkComplete.Empty();

	// No filters are active now
	ActiveFilterName = TEXT( "" );
	CachedLastTaskArrayFilterName = TEXT( "" );


	// Refresh the user interface
	if( GUICallbackObject != NULL )
	{
		GUICallbackObject->Callback_RefreshGUI( ( ETaskBrowserGUIRefreshOptions::Type )(
			ETaskBrowserGUIRefreshOptions::RebuildFilterList |
			ETaskBrowserGUIRefreshOptions::RebuildTaskList |
			ETaskBrowserGUIRefreshOptions::UpdateTaskDescription ) );
	}
}



/**
 * Called when a response is received from the task database
 *
 * @param	InGenericResponse	Response data for the completed request.  This is a polymorphic object
 *								that should be casted to the appropriate response type for the request.
 */
void FTaskDataManager::OnTaskDatabaseRequestCompleted( const FTaskDatabaseResponse* InGenericResponse )
{
	check( InGenericResponse != NULL );
	switch( InGenericResponse->RequestType )
	{
		case ETaskDatabaseRequestType::ConnectToDatabase:
			{
				const FTaskDatabaseResponse_ConnectToDatabase* Response =
					static_cast< const FTaskDatabaseResponse_ConnectToDatabase* >( InGenericResponse );

				if( Response->bSucceeded )
				{
					// We connected successfully!
					ConnectionStatus = ETaskDataManagerStatus::Connected;

					// Store the real name of the user if we were able to retrieve that
					UserRealName = Response->UserRealName;

					// Store resolution values (custom field values)
					ResolutionValues = Response->ResolutionValues;

					// Store name of 'Open' tasks
					OpenTaskStatusPrefix = Response->OpenTaskStatusPrefix;

					// We want to refresh filter names as soon as possible
					bShouldRefreshFilterNames = true;
				}
				else
				{
					// We failed to connect to the server.  We don't want to bother trying again right now.
					ConnectionStatus = ETaskDataManagerStatus::ConnectionFailed;

					FMessageDialog::Open( EAppMsgType::Ok, FText::Format(
							NSLOCTEXT("UnrealEd", "TaskBrowser_Error_ConnectFailed_F", "The Task Browser was unable to connect to the task database server.  The following error message was reported:\n\n{0}\n\nPlease adjust your connection settings using the Settings button at the bottom of the Task Browser and try again by clicking Connect." ),
							FText::FromString(Response->ErrorMessage) ) );
				}
			}
			break;


		case ETaskDatabaseRequestType::DisconnectFromDatabase:
			{
				if( InGenericResponse->bSucceeded )
				{
					// We disconnected successfully!
					ConnectionStatus = ETaskDataManagerStatus::ReadyToConnect;

					// We're disconnected, so clear out state and update the GUI
					CleanUpAfterDisconnect();
				}
				else
				{
					// We failed to disconnect from the server.  Not sure where that leaves us.
					FMessageDialog::Open( EAppMsgType::Ok, FText::Format(
							NSLOCTEXT("UnrealEd", "TaskBrowser_Error_DisconnectFailed_F", "The Task Browser was unable to disconnect to the task database server.  The following error message was reported:\n\n{0}" ),
							FText::FromString(InGenericResponse->ErrorMessage) ) );

					if( !TaskDatabaseSystem::IsConnected() )
					{
						// We were disconnected during the request, so try to handle that gracefully
						ConnectionStatus = ETaskDataManagerStatus::ConnectionFailed;
						CleanUpAfterDisconnect();
					}
				}
			}
			break;


		case ETaskDatabaseRequestType::QueryFilters:
			{
				const FTaskDatabaseResponse_QueryFilters* Response =
					static_cast< const FTaskDatabaseResponse_QueryFilters* >( InGenericResponse );

				if( Response->bSucceeded )
				{
					// Update our list of filters
					CachedFilterNames = Response->FilterNames;


					// Sort the list of filters alphabetically
					CachedFilterNames.Sort();


					// Tell the GUI to update!
					if( GUICallbackObject != NULL )
					{
						GUICallbackObject->Callback_RefreshGUI( ETaskBrowserGUIRefreshOptions::RebuildFilterList );
					}
				}
				else
				{
					// Query failed
					FMessageDialog::Open( EAppMsgType::Ok, FText::Format(
							NSLOCTEXT("UnrealEd", "TaskBrowser_Error_QueryFiltersFailed_F", "The Task Browser encountered an error while querying a list of filters from the server.  The following error message was reported:\n\n{0}" ),
							FText::FromString(Response->ErrorMessage) ) );

					if( !TaskDatabaseSystem::IsConnected() )
					{
						// We were disconnected during the request, so try to handle that gracefully
						ConnectionStatus = ETaskDataManagerStatus::ConnectionFailed;
						CleanUpAfterDisconnect();
					}
				}

				QueryStatus = ETaskDataManagerStatus::Unknown;
			}
			break;


		case ETaskDatabaseRequestType::QueryTasks:
			{
				const FTaskDatabaseResponse_QueryTasks* Response =
					static_cast< const FTaskDatabaseResponse_QueryTasks* >( InGenericResponse );

				if( Response->bSucceeded )
				{
					// Update our list of tasks
					CachedTaskArray = Response->TaskEntries;


					// Tell the GUI to update!
					if( GUICallbackObject != NULL )
					{
						GUICallbackObject->Callback_RefreshGUI( ETaskBrowserGUIRefreshOptions::RebuildTaskList );
					}
				}
				else
				{
					// Query failed
					FMessageDialog::Open( EAppMsgType::Ok, FText::Format(
							NSLOCTEXT("UnrealEd", "TaskBrowser_Error_QueryTasksFailed_F", "The Task Browser encountered an error while querying a list of filtered tasks from the server.  The following error message was reported:\n\n{0}" ),
							FText::FromString(Response->ErrorMessage) ) );

					if( !TaskDatabaseSystem::IsConnected() )
					{
						// We were disconnected during the request, so try to handle that gracefully
						ConnectionStatus = ETaskDataManagerStatus::ConnectionFailed;
						CleanUpAfterDisconnect();
					}
				}

				QueryStatus = ETaskDataManagerStatus::Unknown;
			}
			break;


		case ETaskDatabaseRequestType::QueryTaskDetails:
			{
				const FTaskDatabaseResponse_QueryTaskDetails* Response =
					static_cast< const FTaskDatabaseResponse_QueryTaskDetails* >( InGenericResponse );

				if( Response->bSucceeded )
				{
					// Add/update our task cache
					CachedTaskDetailsMap.Add( Response->TaskEntryDetails.Number, Response->TaskEntryDetails );


					// Tell the GUI to update!
					if( GUICallbackObject != NULL )
					{
						GUICallbackObject->Callback_RefreshGUI(
							ETaskBrowserGUIRefreshOptions::UpdateTaskDescription );
					}
				}
				else
				{
					// Query failed
					FMessageDialog::Open( EAppMsgType::Ok, FText::Format(
							NSLOCTEXT("UnrealEd", "TaskBrowser_Error_QueryTaskDetailsFailed_F", "The Task Browser encountered an error while querying details about a specific task from the server.  The following error message was reported:\n\n{0}" ),
							FText::FromString(Response->ErrorMessage) ) );

					// Invalidate our focused task number so that we won't spam requests
					SetFocusedTaskNumber( INDEX_NONE );

					if( !TaskDatabaseSystem::IsConnected() )
					{
						// We were disconnected during the request, so try to handle that gracefully
						ConnectionStatus = ETaskDataManagerStatus::ConnectionFailed;
						CleanUpAfterDisconnect();
					}
				}

				QueryStatus = ETaskDataManagerStatus::Unknown;
			}
			break;


		case ETaskDatabaseRequestType::MarkTaskComplete:
			{
				const FTaskDatabaseResponse* Response =
					static_cast< const FTaskDatabaseResponse* >( InGenericResponse );

				if( Response->bSucceeded )
				{
					// OK, the task was edited, so we'll remove our cached entry so that the details
					// will be refreshed.
					CachedTaskDetailsMap.Remove( CurrentlyProcessingTaskNumber );

					// Make sure the main task list gets refreshed, since the bug Status field was probably changed
					// We'll clear the last filter name to force a full refresh of the task list.
					// @todo: Improve perf/reduce flicker by only refreshing the task entry that we changed!
					CachedLastTaskArrayFilterName = TEXT( "" );
				}
				else
				{
					// Failed to mark task complete
					FMessageDialog::Open( EAppMsgType::Ok, FText::Format(
							NSLOCTEXT("UnrealEd", "TaskBrowser_Error_MarkCompleteFailed_F", "The Task Browser was unable to mark the specified task(s) as completed.  The following error message was reported:\n\n{0}" ),
							FText::FromString(Response->ErrorMessage) ) );

					if( !TaskDatabaseSystem::IsConnected() )
					{
						// We were disconnected during the request, so try to handle that gracefully
						ConnectionStatus = ETaskDataManagerStatus::ConnectionFailed;
						CleanUpAfterDisconnect();
					}
				}

				QueryStatus = ETaskDataManagerStatus::Unknown;
			}
			break;


		default:
			// Unrecognized response!
			break;			
	}
}