contrib/src/stc/scintilla/src/CellBuffer.h

   1 // Scintilla source code edit control
   2 // CellBuffer.h - manages the text of the document
   3 // Copyright 1998-2000 by Neil Hodgson <neilh@scintilla.org>
   4 // The License.txt file describes the conditions under which this software may be distributed.
   5
   6 #ifndef CELLBUFFER_H
   7 #define CELLBUFFER_H
   8
   9 // This holds the marker identifier and the marker type to display.
  10 // MarkerHandleNumbers are members of lists.
  11 struct MarkerHandleNumber {
  12         int handle;
  13         int number;
  14         MarkerHandleNumber *next;
  15 };
  16
  17 // A marker handle set contains any number of MarkerHandleNumbers
  18 class MarkerHandleSet {
  19         MarkerHandleNumber *root;
  20 public:
  21         MarkerHandleSet();
  22         ~MarkerHandleSet();
  23         int Length();
  24         int NumberFromHandle(int handle);
  25         int MarkValue();        // Bit set of marker numbers
  26         bool Contains(int handle);
  27         bool InsertHandle(int handle, int markerNum);
  28         void RemoveHandle(int handle);
  29         void RemoveNumber(int markerNum);
  30         void CombineWith(MarkerHandleSet *other);
  31 };
  32
  33 // Each line stores the starting position of the first character of the line in the cell buffer
  34 // and potentially a marker handle set. Often a line will not have any attached markers.
  35 struct LineData {
  36         int startPosition;
  37         MarkerHandleSet *handleSet;
  38         LineData() : startPosition(0), handleSet(0) {
  39         }
  40 };
  41
  42 // The line vector contains information about each of the lines in a cell buffer.
  43 class LineVector {
  44 public:
  45         enum { growSize = 4000 };
  46         int lines;
  47         LineData *linesData;
  48         int size;
  49         int *levels;
  50         int sizeLevels;
  51
  52         // Handles are allocated sequentially and should never have to be reused as 32 bit ints are very big.
  53         int handleCurrent;
  54
  55         LineVector();
  56         ~LineVector();
  57         void Init();
  58
  59         void Expand(int sizeNew);
  60         void ExpandLevels(int sizeNew=-1);
  61         void InsertValue(int pos, int value);
  62         void SetValue(int pos, int value);
  63         void Remove(int pos);
  64         int LineFromPosition(int pos);
  65
  66         int AddMark(int line, int marker);
  67         void MergeMarkers(int pos);
  68         void DeleteMark(int line, int markerNum);
  69         void DeleteMarkFromHandle(int markerHandle);
  70         int LineFromHandle(int markerHandle);
  71 };
  72
  73 // Actions are used to store all the information required to perform one undo/redo step.
  74 enum actionType { insertAction, removeAction, startAction };
  75
  76 class Action {
  77 public:
  78         actionType at;
  79         int position;
  80         char *data;
  81         int lenData;
  82
  83         Action();
  84         ~Action();
  85         void Create(actionType at_, int position_=0, char *data_=0, int lenData_=0);
  86         void Destroy();
  87         void Grab(Action *source);
  88 };
  89
  90 enum undoCollectionType { undoCollectNone, undoCollectAutoStart, undoCollectManualStart };
  91
  92 // Holder for an expandable array of characters that supports undo and line markers
  93 // Based on article "Data Structures in a Bit-Mapped Text Editor"
  94 // by Wilfred J. Hansen, Byte January 1987, page 183
  95 class CellBuffer {
  96 private:
  97         char *body;
  98         int size;
  99         int length;
 100         int part1len;
 101         int gaplen;
 102         char *part2body;
 103         bool readOnly;
 104
 105         Action *actions;
 106         int lenActions;
 107         int maxAction;
 108         int currentAction;
 109         undoCollectionType collectingUndo;
 110         int undoSequenceDepth;
 111         int savePoint;
 112
 113         LineVector lv;
 114
 115         SVector<int, 4000> lineStates;
 116
 117         void GapTo(int position);
 118         void RoomFor(int insertionLength);
 119
 120         void EnsureUndoRoom();
 121         void AppendAction(actionType at, int position, char *data, int length);
 122
 123         inline char ByteAt(int position);
 124         void SetByteAt(int position, char ch);
 125
 126 public:
 127
 128         CellBuffer(int initialLength = 4000);
 129         ~CellBuffer();
 130
 131         // Retrieving positions outside the range of the buffer works and returns 0
 132         char CharAt(int position);
 133         void GetCharRange(char *buffer, int position, int lengthRetrieve);
 134         char StyleAt(int position);
 135
 136         int ByteLength();
 137         int Length();
 138         int Lines();
 139         int LineStart(int line);
 140         int LineFromPosition(int pos) { return lv.LineFromPosition(pos); }
 141         const char *InsertString(int position, char *s, int insertLength);
 142         void InsertCharStyle(int position, char ch, char style);
 143
 144         // Setting styles for positions outside the range of the buffer is safe and has no effect.
 145         // True is returned if the style of a character changed.
 146         bool SetStyleAt(int position, char style, char mask=(char)0xff);
 147         bool SetStyleFor(int position, int length, char style, char mask);
 148
 149         const char *DeleteChars(int position, int deleteLength);
 150
 151         bool IsReadOnly();
 152         void SetReadOnly(bool set);
 153
 154         // The save point is a marker in the undo stack where the container has stated that
 155         // the buffer was saved. Undo and redo can move over the save point.
 156         void SetSavePoint();
 157         bool IsSavePoint();
 158
 159         // Line marker functions
 160         int AddMark(int line, int markerNum);
 161         void DeleteMark(int line, int markerNum);
 162         void DeleteMarkFromHandle(int markerHandle);
 163         int GetMark(int line);
 164         void DeleteAllMarks(int markerNum);
 165         int LineFromHandle(int markerHandle);
 166
 167         // Without undo
 168         void BasicInsertString(int position, char *s, int insertLength);
 169         void BasicDeleteChars(int position, int deleteLength);
 170
 171         undoCollectionType SetUndoCollection(undoCollectionType collectUndo);
 172         bool IsCollectingUndo();
 173         void AppendUndoStartAction();
 174         void BeginUndoAction();
 175         void EndUndoAction();
 176         void DeleteUndoHistory();
 177
 178         // To perform an undo, StartUndo is called to retreive the number of steps, then UndoStep is
 179         // called that many times. Similarly for redo.
 180         bool CanUndo();
 181         int StartUndo();
 182         const Action &UndoStep();
 183         bool CanRedo();
 184         int StartRedo();
 185         const Action &RedoStep();
 186
 187         int SetLineState(int line, int state);
 188         int GetLineState(int line);
 189         int GetMaxLineState();
 190
 191         int SetLevel(int line, int level);
 192         int GetLevel(int line);
 193 };
 194
 195 #define CELL_SIZE       2
 196
 197 #endif