src/CursorSlice.h

   1 // -*- C++ -*-
   2 /**
   3  * \file CursorSlice.h
   4  * This file is part of LyX, the document processor.
   5  * Licence details can be found in the file COPYING.
   6  *
   7  * \author Lars Gullik Bjønnes
   8  * \author Matthias Ettrich
   9  * \author John Levon
  10  * \author André Pönitz
  11  * \author Dekel Tsur
  12  * \author Jürgen Vigna
  13  *
  14  * Full author contact details are available in file CREDITS.
  15  */
  16
  17 #ifndef CURSORSLICE_H
  18 #define CURSORSLICE_H
  19
  20 #include "support/types.h"
  21 #include "support/strfwd.h"
  22 #include "insets/Inset.h"
  23
  24
  25 namespace lyx {
  26
  27 class Inset;
  28 class MathData;
  29 class Text;
  30 class Paragraph;
  31
  32 /// This encapsulates a single slice of a document iterator as used e.g.
  33 /// for cursors.
  34
  35 // After IU, the distinction of MathInset and InsetOld as well as
  36 // that of MathData and Text should vanish. They are conceptually the
  37 // same (now...)
  38
  39 class CursorSlice {
  40 public:
  41         /// Those needs inset_ access.
  42         ///@{
  43         friend class DocIterator;
  44         friend class StableDocIterator;
  45         ///@}
  46
  47         /// type for cell number in inset
  48         typedef size_t idx_type;
  49         /// type for row indices
  50         typedef size_t row_type;
  51         /// type for col indices
  52         typedef size_t col_type;
  53
  54         ///
  55         CursorSlice();
  56         ///
  57         explicit CursorSlice(Inset &);
  58
  59         /// comparison operators.
  60         //@{
  61         friend bool operator==(CursorSlice const &, CursorSlice const &);
  62         friend bool operator!=(CursorSlice const &, CursorSlice const &);
  63         friend bool operator<(CursorSlice const &, CursorSlice const &);
  64         friend bool operator>(CursorSlice const &, CursorSlice const &);
  65         friend bool operator<=(CursorSlice const &, CursorSlice const &);
  66         //@}
  67
  68         /// the current inset
  69         Inset & inset() const { return *inset_; }
  70         /// return the cell this cursor is in
  71         idx_type idx() const { return idx_; }
  72         /// return the cell this cursor is in
  73         idx_type & idx() { return idx_; }
  74         /// return the last cell in this inset
  75         idx_type lastidx() const { return nargs() - 1; }
  76         /// return the offset of the paragraph this cursor is in
  77         pit_type pit() const { return pit_; }
  78         /// set the offset of the paragraph this cursor is in
  79         pit_type & pit() { return pit_; }
  80         /// return the last paragraph offset within the ParagraphList
  81         pit_type lastpit() const;
  82         /// increments the paragraph this cursor is in
  83         void incrementPar();
  84         /// decrements the paragraph this cursor is in
  85         void decrementPar();
  86         /// return the position within the paragraph
  87         pos_type pos() const { return pos_; }
  88         /// return the position within the paragraph
  89         pos_type & pos() { return pos_; }
  90         /// return the last position within the paragraph
  91         pos_type lastpos() const;
  92         /// return the number of embedded cells
  93         size_t nargs() const { return inset_->nargs(); }
  94         /// return the number of columns (1 in non-grid-like insets)
  95         size_t ncols() const { return inset_->ncols(); }
  96         /// return the number of rows (1 in non-grid-like insets)
  97         size_t nrows() const { return inset_->nrows(); }
  98         /*!
  99          * \return the grid row of the current cell.
 100          * This does only make sense in grid like insets.
 101          */
 102         row_type row() const;
 103         /*!
 104          * \return the grid column of the current cell.
 105          * This does only make sense in grid like insets.
 106          */
 107         col_type col() const;
 108
 109         ///
 110         /// texted specific stuff
 111         ///
 112         /// returns text corresponding to this position
 113         Text * text() const { return inset_->getText(idx_); }
 114         /// paragraph in this cell
 115         Paragraph & paragraph() const;
 116
 117         ///
 118         /// mathed specific stuff
 119         ///
 120         /// returns the owning inset if it is a InsetMath, else 0
 121         InsetMath * asInsetMath() const { return inset_->asInsetMath(); }
 122         /// returns cell corresponding to this position
 123         MathData & cell() const;
 124
 125         /// write some debug information to \p os
 126         friend std::ostream & operator<<(std::ostream &, CursorSlice const &);
 127         /// move to next position
 128         void forwardPos();
 129         /// move to previous position
 130         void backwardPos();
 131         /// move to next cell
 132         void forwardIdx();
 133         /// move to previous cell
 134         void backwardIdx();
 135         /// are we at the end of this slice
 136         bool at_end() const;
 137         /// are we at the start of this slice
 138         bool at_begin() const;
 139
 140 private:
 141
 142         /// pointer to 'owning' inset. This is some kind of cache.
 143         Inset * inset_;
 144
 145         /*!
 146          * Cell index of a position in this inset.
 147          * This is the primary cell information also for grid like insets,
 148          * although we have the convenience functions row() and col() for
 149          * those * and column changes every time the number of columns ornumber
 150          * of rows changes. Normally the cursor should stay in the same cell,
 151          * so these changes should typically be performed like the following:
 152          * \code
 153          * row_type const r = cur.row();
 154          * col_type const c = cur.col();
 155          * // change nrows() and/or ncols()
 156          * cur.idx = index(r, c);
 157          * \endcode
 158          */
 159         idx_type idx_;
 160         /// paragraph in this cell (used by texted)
 161         pit_type pit_;
 162         /// position in this cell
 163         pos_type pos_;
 164 };
 165
 166
 167 } // namespace lyx
 168
 169 #endif