kicad/eeschema/schematic_undo_redo.cpp

	/********************************************/
	/*  library editor: undo and redo functions */
	/********************************************/

#include "fctsys.h"
#include "gr_basic.h"

#include "common.h"
#include "program.h"
#include "libcmp.h"
#include "general.h"
#include "id.h"

#include "protos.h"

/* Functions to undo and redo edit commands.
commmands to undo are in CurrentScreen->m_UndoList
commmands to redo are in CurrentScreen->m_RedoList

m_UndoList and m_RedoList are a linked list of DrawPickedStruct.
each DrawPickedStruct has its .m_Son member pointing to an item to undo or redo,
or to a list of DrawPickedStruct which points (.m_PickedStruct membre) 
the items to undo or redo

there are 3 cases:
	- delete item(s) command
	- change item(s) command
	- add item(s) command

Undo command
- delete item(s) command:
	deleted items are moved in undo list

- change item(s) command
	A copy of item(s) is made (a DrawPickedStruct list of wrappers)
	the .m_Image member of each wrapper points the modified item.

- add item(s) command
	A list of item(s) is made
	the .m_Image member of each wrapper points the new item.

Redo command
- delete item(s) old command:
	deleted items are moved in EEDrawList list

- change item(s) command
	the copy of item(s) is moved in Undo list

- add item(s) command
	The list of item(s) is used to create a deleted list in undo list
	(same as a delete command)

A problem is the hierarchical sheet handling.
	the data associated (subhierarchy, uno/redo list) is deleted only
	when the sheet is really deleted (i.e. when deleted from undo or redo list)
	and not when it is a copy.
*/


/************************************/
void SwapData(EDA_BaseStruct * Item)
/************************************/
/* Used if undo / redo command:
	swap data between Item and its copy, pointed by its .m_Image member
*/
{
	if ( Item == NULL ) return;
	EDA_BaseStruct * image = Item->m_Image;
	if (image == NULL ) return;
	
	switch ( Item->m_StructType )
	{
	case DRAW_POLYLINE_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((DrawPolylineStruct*)Item)
		#define DEST ((DrawPolylineStruct*)image)
		break;

	case DRAW_JUNCTION_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((DrawJunctionStruct*)Item)
		#define DEST ((DrawJunctionStruct*)image)
		EXCHG(SOURCE->m_Pos, DEST->m_Pos);
		break;

	case DRAW_LABEL_STRUCT_TYPE:
	case DRAW_GLOBAL_LABEL_STRUCT_TYPE:
	case DRAW_TEXT_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((DrawTextStruct*)Item)
		#define DEST ((DrawTextStruct*)image)
		DEST->SwapData(SOURCE);
		break;

	case DRAW_LIB_ITEM_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((EDA_SchComponentStruct*)Item)
		#define DEST ((EDA_SchComponentStruct*)image)
		DEST->SwapData(SOURCE);
		break;

	case DRAW_SEGMENT_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((EDA_DrawLineStruct*)Item)
		#define DEST ((EDA_DrawLineStruct*)image)
		EXCHG(SOURCE->m_Start, DEST->m_Start);
		EXCHG(SOURCE->m_End, DEST->m_End);
		break;

	case DRAW_BUSENTRY_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((DrawBusEntryStruct*)Item)
		#define DEST ((DrawBusEntryStruct*)image)
		EXCHG(SOURCE->m_Pos, DEST->m_Pos);
		EXCHG(SOURCE->m_Size, DEST->m_Size);
		break;

	case DRAW_SHEET_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((DrawSheetStruct*)Item)
		#define DEST ((DrawSheetStruct*)image)
		DEST->SwapData(SOURCE);
		break;

	case DRAW_MARKER_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((DrawMarkerStruct*)Item)
		#define DEST ((DrawMarkerStruct*)image)
		EXCHG(SOURCE->m_Pos, DEST->m_Pos);
		break;

	case DRAW_SHEETLABEL_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((DrawSheetLabelStruct*)Item)
		#define DEST ((DrawSheetLabelStruct*)image)
		EXCHG(SOURCE->m_Edge, DEST->m_Edge);
		EXCHG(SOURCE->m_Shape, DEST->m_Shape);
		break;

	case DRAW_NOCONNECT_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((DrawNoConnectStruct*)Item)
		#define DEST ((DrawNoConnectStruct*)image)
		EXCHG(SOURCE->m_Pos, DEST->m_Pos);
		break;

	case DRAW_PART_TEXT_STRUCT_TYPE:
		#undef SOURCE
		#undef DEST
		#define SOURCE ((DrawPolylineStruct*)Item)
		#define DEST ((DrawPolylineStruct*)image)
		break;

	// not directly used in schematic:
	default:
		DisplayInfo(NULL, wxT("SwapData() error: unexpected type"));
		break;
	}
}
/***********************************************************************/
void WinEDA_SchematicFrame::SaveCopyInUndoList(EDA_BaseStruct * ItemToCopy,
			int flag_type_command)
/***********************************************************************/
/* Create a copy of the current schematic draw list, and put it in the undo list.
	A DrawPickedStruct wrapper is created to handle the draw list.
	the .m_Son of this wrapper points the list of items
	
	flag_type_command =
		0 (unspecified)
		IS_CHANGED
		IS_NEW
		IS_DELETED
		IS_WIRE_IMAGE
	
	for 0: only a wrapper is created. The used must init the .Flags member of the
	wrapper, and add the item list to the wrapper
	If it is a delete command, items are put on list with the .Flags member set to IS_DELETED.
	When it will be really deleted, the EEDrawList and the subhierarchy will be deleted.
	If it is only a copy, the EEDrawList and the subhierarchy must NOT be deleted.
	
	Note:
	Edit wires and busses is a bit complex.
	because when a new wire is added, modifications in wire list
	(wire concatenation) there are modified items, deleted items and new items
	so flag_type_command is IS_WIRE_IMAGE: the struct ItemToCopy is a list of wires
	saved in Undo List (for Undo or Redo commands, saved wires will be exchanged with current wire list
*/
{
EDA_BaseStruct * CopyItem;

	DrawPickedStruct * NewList = new DrawPickedStruct(NULL);
	NewList->m_Flags = flag_type_command;
	
	if ( ItemToCopy )
	{
		switch ( flag_type_command )
		{
			case 0:
				break;
			
			case IS_CHANGED:	/* Create a copy of schematic */
				NewList->m_Son = CopyItem = DuplicateStruct(ItemToCopy);
				if ( ItemToCopy->m_StructType == DRAW_PICK_ITEM_STRUCT_TYPE)
				{
					DrawPickedStruct * PickedList = (DrawPickedStruct *) CopyItem;
					while (PickedList)
					{
						CopyItem = PickedList->m_PickedStruct;
						CopyItem->m_Flags = flag_type_command;
						PickedList->m_Image = CopyItem->m_Image;
						PickedList = (DrawPickedStruct *)PickedList->Pnext;
					}
				}
				else
				{
					CopyItem->m_Flags = flag_type_command;
					CopyItem->m_Image = ItemToCopy;
				}
				break;
	
			case IS_NEW:
				if ( ItemToCopy->m_StructType == DRAW_PICK_ITEM_STRUCT_TYPE)
				{
					NewList->m_Son = ItemToCopy;
					DrawPickedStruct * PickedList = (DrawPickedStruct *) ItemToCopy;
					while (PickedList)
					{
						CopyItem = PickedList->m_PickedStruct;
						PickedList->m_Image = CopyItem;
						PickedList->m_PickedStruct = NULL;
						PickedList->m_Flags = flag_type_command;
						PickedList = (DrawPickedStruct *)PickedList->Pnext;
					}
				}
				else
				{
					NewList->m_Image = ItemToCopy;
				}
				break;
				
			case IS_NEW|IS_CHANGED:
			case IS_WIRE_IMAGE:
				NewList->m_Son = ItemToCopy;
				break;
	
			case IS_DELETED:
				NewList->m_Son = ItemToCopy;
				ItemToCopy->m_Flags = flag_type_command;
				if ( ItemToCopy->m_StructType == DRAW_PICK_ITEM_STRUCT_TYPE )
				{
					DrawPickedStruct * PickedList = (DrawPickedStruct *) ItemToCopy;
					while (PickedList)
					{
						CopyItem = PickedList->m_PickedStruct;
						CopyItem->m_Flags = flag_type_command;
						PickedList->m_Flags = flag_type_command;
						PickedList = (DrawPickedStruct *)PickedList->Pnext;
					}
				}
				break;
				
			default:
				DisplayError(this, wxT("SaveCopyInUndoList() error"));
				break;
		}
	}
	/* Save the copy in undo list */
	GetScreen()->AddItemToUndoList(NewList);

	/* Clear redo list, because after new save there is no redo to do */
	GetScreen()->ClearUndoORRedoList(GetScreen()->m_RedoList);
	GetScreen()->m_RedoList = NULL;
}

/**********************************************************/
void WinEDA_SchematicFrame::GetSchematicFromRedoList(void)
/**********************************************************/
/* Redo the last edition:
	- Save the current schematic in undo list
	- Get the old version
*/
{
	if ( GetScreen()->m_RedoList == NULL ) return;
		
	/* Get the old wrapper and put it in UndoList */
	DrawPickedStruct * List = (DrawPickedStruct *)GetScreen()->GetItemFromRedoList();
	GetScreen()->AddItemToUndoList(List);
	/* Redo the command: */
	PutDataInPreviousState(List);
	
	CurrentDrawItem = NULL;
	GetScreen()->SetModify();
	ReCreateHToolbar();
	SetToolbars();
}


/***************************************************************************/
void WinEDA_SchematicFrame::PutDataInPreviousState(DrawPickedStruct * List)
/***************************************************************************/
/* Used in undo or redo command.
	Put data pointed by List in the previous state, i.e. the state memorised by List
*/
{
EDA_BaseStruct * FirstItem = List->m_Son;
EDA_BaseStruct * item;
DrawPickedStruct * PickedList;
	
	switch ( List->m_Flags )
	{
		case IS_CHANGED:	/* Exchange old and new data for each item */
			if ( FirstItem == NULL )
			{
				DisplayError(this, wxT("PutDataInPreviousState() error : Null item"));
				break;
			}				
			if ( FirstItem->m_StructType == DRAW_PICK_ITEM_STRUCT_TYPE)
			{
				DrawPickedStruct * PickedList = (DrawPickedStruct *) FirstItem;
				while ( PickedList )
				{
					SwapData(PickedList->m_PickedStruct);
					PickedList = PickedList->Next();
				}
			}
			else
			{
				SwapData(FirstItem);
			}
			break;

		case IS_NEW:		/* new items are deleted */
			List->m_Flags = IS_DELETED;
			if ( FirstItem && FirstItem->m_StructType == DRAW_PICK_ITEM_STRUCT_TYPE)
			{
				PickedList = (DrawPickedStruct *) FirstItem;
				while ( PickedList )
				{
					item = PickedList->m_Image;
					GetScreen()->RemoveFromDrawList(item);
					item->m_Flags = IS_DELETED;
					PickedList->m_PickedStruct = item;
					PickedList->m_Flags = IS_DELETED;
					PickedList = PickedList->Next();
				}
			}
			else
			{
				FirstItem = List->m_Image;
				GetScreen()->RemoveFromDrawList(FirstItem);
				FirstItem->m_Flags = IS_DELETED;
				List->m_Son = FirstItem;
			}
			break;

		case IS_DELETED:	/* deleted items are put in EEdrawList, as new items */
			List->m_Flags = IS_NEW;
			if ( FirstItem->m_StructType == DRAW_PICK_ITEM_STRUCT_TYPE)
			{
				PickedList = (DrawPickedStruct *) FirstItem;
				while ( PickedList )
				{
					item = PickedList->m_PickedStruct;
					item->Pnext = GetScreen()->EEDrawList;
					GetScreen()->EEDrawList = item;
					item->m_Flags = 0;
					PickedList->m_PickedStruct = NULL;
					PickedList->m_Image = item;
					PickedList->m_Flags = IS_NEW;
					PickedList = PickedList->Next();
				}
			}
			else
			{
				FirstItem->Pnext = GetScreen()->EEDrawList;
				GetScreen()->EEDrawList = FirstItem;
				FirstItem->m_Flags = 0;
				List->m_Image = List->m_Son;
				List->m_Son = NULL;
			}
			break;
		
		case IS_WIRE_IMAGE:
			/* Exchange the current wires and the oild wires */
			List->m_Son = GetScreen()->ExtractWires(FALSE);
			while ( FirstItem )
			{
				EDA_BaseStruct * nextitem = FirstItem->Pnext;
				FirstItem->Pnext = GetScreen()->EEDrawList;
				GetScreen()->EEDrawList = FirstItem;
				FirstItem->m_Flags = 0;
				FirstItem = nextitem;
			}
			break;

		case IS_NEW|IS_CHANGED:
		case IS_DELETED|IS_CHANGED:
			if ( !FirstItem || FirstItem->m_StructType != DRAW_PICK_ITEM_STRUCT_TYPE)
			{
				DisplayError(this, wxT("GetSchematicFromUndoList() error: Pickstruct expected"));
				break;
			}
			PickedList = (DrawPickedStruct *) FirstItem;
			while ( PickedList )
			{
				switch (PickedList->m_Flags)
				{
				case IS_CHANGED:
					SwapData(PickedList->m_PickedStruct);
					break;
				
				case IS_NEW:
					item = PickedList->m_Image;
					GetScreen()->RemoveFromDrawList(item);
					item->m_Flags = IS_DELETED;
					PickedList->m_PickedStruct = item;
					PickedList->m_Flags = IS_DELETED;
					break;
				
				case IS_DELETED:
					item = PickedList->m_PickedStruct;
					item->Pnext = GetScreen()->EEDrawList;
					GetScreen()->EEDrawList = item;
					item->m_Flags = 0;
					PickedList->m_PickedStruct = NULL;
					PickedList->m_Image = item;
					PickedList->m_Flags = IS_NEW;
					break;
				}
				PickedList = PickedList->Next();
			}
			break;

		default:
			DisplayError(this, wxT("GetSchematicFromUndoList() error: Unknown cmd"));
			break;
	}
}

/**********************************************************/
void WinEDA_SchematicFrame::GetSchematicFromUndoList(void)
/**********************************************************/
/* Undo the last edition:
	- Save the current schematic in Redo list
	- Get an old version of the schematic
*/
{
	if ( GetScreen()->m_UndoList == NULL ) return;
	
	/* Get the old wrapper and put it in RedoList (the real data list is the m_Son member) */
	DrawPickedStruct * List = (DrawPickedStruct *)GetScreen()->GetItemFromUndoList();
	GetScreen()->AddItemToRedoList(List);
	/* Undo the command */
	PutDataInPreviousState(List);

	CurrentDrawItem = NULL;
	GetScreen()->SetModify();
	ReCreateHToolbar();
	SetToolbars();
}


/*********************************************************/
void SCH_SCREEN::ClearUndoORRedoList(EDA_BaseStruct *List)
/*********************************************************/
/* free the undo or redo list from List element
	Wrappers are deleted.
	datas pointed by wrappers are deleted if not flagged IS_NEW
	because they are copy of used data or they are not in use (DELETED)
*/
{
EDA_BaseStruct *nextitem;
EDA_BaseStruct * FirstItem;
int CmdType;
	
	if ( List == NULL ) return;

	for ( ; List != NULL; List = nextitem )
	{
		nextitem = List->Pnext;
		FirstItem = List->m_Son;
		CmdType = List->m_Flags;

		delete List;

		if (FirstItem == NULL ) continue;
			
		if ( FirstItem->m_StructType == DRAW_PICK_ITEM_STRUCT_TYPE )
		{
			EDA_BaseStruct * item;
			DrawPickedStruct * PickedList = (DrawPickedStruct *) FirstItem;
			while ( PickedList )	// delete wrapper list and copies
			{
				item = PickedList->m_PickedStruct;
				if ( item )
				{
					if ( item->m_StructType == DRAW_SHEET_STRUCT_TYPE )
					{
						DrawSheetStruct * sheet = (DrawSheetStruct*)item;
						/* Delete sub hierarchy if the sheet must be deleted */
						if ( (sheet->m_Flags & IS_DELETED) != 0 )
							DeleteSubHierarchy(sheet, FALSE);
						else	/* EEDrawList, UndoList and Redo list are shared, and are deleted
								only if sheet is deleted */
						{
							if ( (item->m_Flags & IS_NEW) == 0 )
							{
								sheet->EEDrawList = NULL;
								sheet->m_UndoList = NULL;
								sheet->m_RedoList = NULL;
							}
						}
					}
					if ( (item->m_Flags & IS_NEW) == 0 ) delete item;
				}
				DrawPickedStruct * wrapper = PickedList;
				PickedList = PickedList->Next();
				delete wrapper;
			}
		}
		else	// This is a single item: deleted copy
		{
			if ( CmdType == IS_WIRE_IMAGE )
			{
				while ( FirstItem )
				{
					EDA_BaseStruct * nextitem = FirstItem->Pnext;
					delete FirstItem;
					FirstItem = nextitem;
				}
			}
			else
			{
				if ( FirstItem->m_StructType == DRAW_SHEET_STRUCT_TYPE )
				{
					DrawSheetStruct * sheet = (DrawSheetStruct*)FirstItem;
					/* Delete hierarchy if the sheet must be deleted */
					if ( (sheet->m_Flags & IS_DELETED) == IS_DELETED )
						DeleteSubHierarchy(sheet, FALSE);
					else
					{
						if ( (FirstItem->m_Flags & IS_NEW) == 0 )
						{
							sheet->EEDrawList = NULL;
							sheet->m_UndoList = NULL;
							sheet->m_RedoList = NULL;
						}
					}
				}
				if ( (FirstItem->m_Flags & IS_NEW) == 0 ) delete FirstItem;
			}
		}
	}
}

/*****************************************/
void SCH_SCREEN::ClearUndoRedoList(void)
/*****************************************/
/* free the undo and the redo lists
*/
{
	ClearUndoORRedoList(m_UndoList); m_UndoList = NULL;
	ClearUndoORRedoList(m_RedoList); m_RedoList = NULL;
}

/***********************************************************/
void SCH_SCREEN::AddItemToUndoList(EDA_BaseStruct * newitem)
/************************************************************/
/* Put newitem in head of undo list
	Deletes olds items if > count max.
*/
{
int ii;
EDA_BaseStruct * item, *nextitem;
	
	if ( newitem == NULL ) return;
	
	if ( m_UndoList ) m_UndoList->Pback = newitem;
	newitem->Pnext = m_UndoList;
	newitem->Pback = NULL;
	m_UndoList = newitem;

	/* Free oldest items, if count max reached */
	for ( ii = 0, item = m_UndoList; ii < m_UndoRedoCountMax; ii++ )
	{
		if ( item->Pnext == NULL ) return;
		item = item->Pnext;
	}
	
	if ( item == NULL ) return;
	
	nextitem = item->Pnext;
	item->Pnext = NULL;	// Set end of chain
	
	// Delete the extra  items
	ClearUndoORRedoList(nextitem);
}

/***********************************************************/
void SCH_SCREEN::AddItemToRedoList(EDA_BaseStruct * newitem)
/***********************************************************/
{
int ii;
EDA_BaseStruct * item, *nextitem;
	
	if ( newitem == NULL ) return;
		
	newitem->Pback = NULL;
	newitem->Pnext = m_RedoList;
	m_RedoList = newitem;
	/* Free first items, if count max reached */
	for ( ii = 0, item = m_RedoList; ii < m_UndoRedoCountMax; ii++ )
	{
		if ( item->Pnext == NULL ) break;
		item = item->Pnext;
	}
	
	if ( item == NULL ) return;
	
	nextitem = item->Pnext;
	item->Pnext = NULL;	// Set end of chain
	
	// Delete the extra items
	ClearUndoORRedoList(nextitem);
}