// -*- C++ -*-
-/* This file is part of
- * ======================================================
- *
- * LyX, The Document Processor
- *
- * Copyright (C) 1995 Matthias Ettrich
+/**
+ * \file lyxcursor.h
+ * Copyright 1995-2001 the LyX Team
+ * Read the file COPYING
*
- * ====================================================== */
+ * \author Matthias Ettrich
+ */
#ifndef LYXCURSOR_H
#define LYXCURSOR_H
-#include "lyxparagraph.h"
+#include "support/types.h"
-struct Row;
+class Paragraph;
+class Row;
-/** All these variavles should be explained. Matthias?
+/**
+ * The cursor class describes the position of a cursor within a document.
+ * Several cursors exist within LyX; for example, when locking an inset,
+ * the position of the cursor in the containing inset is stored.
+ *
+ * FIXME: true ?
*/
-struct LyXCursor {
- ///
- LyXParagraph * par;
- ///
- LyXParagraph::size_type pos;
- ///
- int x;
- ///
- int x_fix;
- ///
- long y;
- ///
- Row * row;
+class LyXCursor {
+public:
+ LyXCursor();
+ /// set the paragraph that contains this cursor
+ void par(Paragraph * p);
+ /// return the paragraph this cursor is in
+ Paragraph * par() const;
+ /// set the position within the paragraph
+ void pos(lyx::pos_type p);
+ /// return the position within the paragraph
+ lyx::pos_type pos() const;
+ /// FIXME
+ void boundary(bool b);
+ /// FIXME
+ bool boundary() const;
+ /// set the x position in pixels
+ void x(int i);
+ /// return the x position in pixels
+ int x() const;
+ /// set the stored next-line position when at the end of a row
+ void ix(int i);
+ /**
+ * Return the x position of the start of the next row, when this
+ * cursor is at the end of the previous row, for insets that take
+ * a full row.
+ *
+ * FIXME: explain why we need this ?
+ */
+ int ix() const;
+ /// set the cached x position
+ void x_fix(int i);
+ /**
+ * Return the cached x position of the cursor. This is used for when
+ * we have text like :
+ *
+ * blah blah blah blah| blah blah blah
+ * blah blah blah
+ * blah blah blah blah blah blah
+ *
+ * When we move onto row 3, we would like to be vertically aligned
+ * with where we were in row 1, despite the fact that row 2 is
+ * shorter than x()
+ */
+ int x_fix() const;
+ /// set the y position in pixels
+ void y(int i);
+ /// return the y position in pixels
+ int y() const;
+ /// set the stored next-line y position when at the end of a row
+ void iy(int i);
+ /**
+ * Return the y position of the start of the next row, when this
+ * cursor is at the end of the previous row, for insets that take
+ * a full row.
+ *
+ * FIXME: explain why we need this ? especially for y...
+ */
+ int iy() const;
+ /// set the row of the paragraph the cursor is in
+ void row(Row * r);
+ /// return the row of the paragraph this cursor is in
+ Row * row() const;
+ /// set the stored next row
+ void irow(Row * r);
+ /**
+ * Return the next row, when this
+ * cursor is at the end of the previous row, for insets that take
+ * a full row.
+ *
+ * FIXME: explain why we need this ? especially for y...
+ */
+ Row * irow() const;
+private:
+ /// The paragraph the cursor is in.
+ Paragraph * par_;
+ /// The position inside the paragraph
+ lyx::pos_type pos_;
+ /**
+ * When the cursor position is i, is the cursor is after the i-th char
+ * or before the i+1-th char ? Normally, these two interpretations are
+ * equivalent, except when the fonts of the i-th and i+1-th char
+ * differ.
+ * We use boundary_ to distinguish between the two options:
+ * If boundary_=true, then the cursor is after the i-th char
+ * and if boundary_=false, then the cursor is before the i+1-th char.
+ *
+ * We currently use the boundary only when the language direction of
+ * the i-th char is different than the one of the i+1-th char.
+ * In this case it is important to distinguish between the two
+ * cursor interpretations, in order to give a reasonable behavior to
+ * the user.
+ */
+ bool boundary_;
+ /// the pixel x position
+ int x_;
+ /// the stored next-row x position
+ int ix_;
+ /// the cached x position
+ int x_fix_;
+ /// the pixel y position
+ int y_;
+ /// the stored next-row y position
+ int iy_;
+ /// the containing row
+ Row * row_;
+ /// the containing row for the next line
+ Row * irow_;
};
-#endif
+/// these three dictate the others
+inline
+bool operator==(LyXCursor const & a, LyXCursor const & b)
+{
+ return (a.par() == b.par())
+ && (a.pos() == b.pos())
+ && a.boundary() == b.boundary();
+}
+
+inline
+bool operator!=(LyXCursor const & a, LyXCursor const & b)
+{
+ return !(a == b);
+}
+
+/// only compares y() and pos(). Can this be done in another way?
+inline
+bool operator<(LyXCursor const & a, LyXCursor const & b)
+{
+ return (a.y() < b.y() && a.pos() < b.pos());
+}
+
+inline
+bool operator>(LyXCursor const & a, LyXCursor const & b)
+{
+ return b < a;
+}
+
+inline
+bool operator>=(LyXCursor const & a, LyXCursor const & b)
+{
+ return !(a < b);
+}
+
+
+inline
+bool operator<=(LyXCursor const & a, LyXCursor const & b)
+{
+ return !(a > b);
+}
+
+#endif // LYXCURSOR_H