00001 /* AbiWord 00002 * Copyright (C) 1998 AbiSource, Inc. 00003 * 00004 * This program is free software; you can redistribute it and/or 00005 * modify it under the terms of the GNU General Public License 00006 * as published by the Free Software Foundation; either version 2 00007 * of the License, or (at your option) any later version. 00008 * 00009 * This program is distributed in the hope that it will be useful, 00010 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00012 * GNU General Public License for more details. 00013 * 00014 * You should have received a copy of the GNU General Public License 00015 * along with this program; if not, write to the Free Software 00016 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 00017 * 02110-1301 USA. 00018 */ 00019 00020 00021 #ifndef PX_CHANGEHISTORY_H 00022 #define PX_CHANGEHISTORY_H 00023 00024 #include "ut_types.h" 00025 #include "px_ChangeRecord.h" 00026 00027 // px_ChangeHistory implements a history mechanism of PX_ChangeRecords. 00028 // This is used for undo and redo. We implement a first-order undo/redo. 00029 // (We do not put undo commands into the undo history like emacs.) 00030 // As an editing operation is performed, one or more ChangeRecords will 00031 // be generated. These are appended to the history. The undo command 00032 // will take the last ChangeRecord and reverse its effect and decrement 00033 // the undo position. ChangeRecords which are undone are not deleted 00034 // from the end of the history until a non-redo command is performed 00035 // (and thus invalidating what needs to be redone). A redo command will 00036 // re-apply the ChangeRecord and advance the undo position. 00037 00038 class pt_PieceTable; 00039 class PD_Document; 00040 00041 class ABI_EXPORT px_ChangeHistory 00042 { 00043 public: 00044 px_ChangeHistory(pt_PieceTable * pT); 00045 ~px_ChangeHistory(); 00046 00047 // addChangeRecord -- append the given cr to the history 00048 // at the current position and advance 00049 // the current position. also deletes 00050 // any (now) invalid redo items beyond 00051 // the current position. 00052 // getUndo -- fetch the cr immediately prior to the current 00053 // position. 00054 // getRedo -- fetch the cr immediately after the current position. 00055 // 00056 // didUndo -- decrement the current position (to compensate for 00057 // having just performed the undo). 00058 // didRedo -- increment the current position (to compensate for 00059 // having just performed the redo). 00060 00061 bool addChangeRecord(PX_ChangeRecord * pcr); 00062 bool canDo(bool bUndo) const; 00063 00064 void setSavePosition(UT_sint32 savePosition); 00065 UT_sint32 getSavePosition(void) const; 00066 00067 UT_uint32 getUndoPos(void) const; 00068 00069 bool getUndo(PX_ChangeRecord ** ppcr, bool bStatic=false) const; 00070 bool getNthUndo(PX_ChangeRecord ** ppcr, UT_uint32 undoNdx) const; 00071 bool getRedo(PX_ChangeRecord ** ppcr) const; 00072 bool didUndo(void); 00073 bool didRedo(void); 00074 void coalesceHistory(const PX_ChangeRecord * pcr); 00075 00076 void setClean(void); 00077 bool isDirty(void) const; 00078 00079 void clearHistory(); 00080 PD_Document * getDoc(void) const; 00081 bool getCRRange(PX_ChangeRecord * pcr,PT_DocPosition & posLow, PT_DocPosition &posHigh) const; 00082 bool doesOverlap(PX_ChangeRecord * pcr, PT_DocPosition low, PT_DocPosition high) const; 00083 void setScanningUndoGLOB(bool bTrue) const 00084 { m_bScanUndoGLOB = bTrue;} 00085 bool isScanningUndoGLOB(void) const 00086 { return m_bScanUndoGLOB;} 00087 00088 #ifdef PT_TEST 00089 void __dump(FILE* fp) const; 00090 #endif 00091 00092 protected: 00093 void _invalidateRedo(void); 00094 void _invalidateHistory(void); 00095 void _printHistory(UT_sint32 i) const; 00096 00097 UT_GenericVector<PX_ChangeRecord *> m_vecChangeRecords; 00098 UT_sint32 m_undoPosition; 00099 UT_sint32 m_savePosition; 00100 pt_PieceTable * m_pPT; 00101 mutable UT_sint32 m_iAdjustOffset; 00102 mutable bool m_bOverlap; 00103 mutable UT_sint32 m_iMinUndo; 00104 mutable bool m_bScanUndoGLOB; 00105 }; 00106 00107 #endif /* PX_CHANGEHISTORY_H */
1.7.1