starmath/inc/visitors.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9 #ifndef INCLUDED_STARMATH_INC_VISITORS_HXX
  10 #define INCLUDED_STARMATH_INC_VISITORS_HXX
  11
  12 #include <sal/config.h>
  13
  14 #include <sal/log.hxx>
  15
  16 #include "node.hxx"
  17 #include "caret.hxx"
  18 #include <memory>
  19
  20 /** Base class for visitors that visits a tree of SmNodes
  21  * @remarks all methods have been left abstract to ensure that implementers
  22  * don't forget to implement one.
  23  */
  24 class SmVisitor
  25 {
  26 public:
  27     virtual void Visit( SmTableNode* pNode ) = 0;
  28     virtual void Visit( SmBraceNode* pNode ) = 0;
  29     virtual void Visit( SmBracebodyNode* pNode ) = 0;
  30     virtual void Visit( SmOperNode* pNode ) = 0;
  31     virtual void Visit( SmAlignNode* pNode ) = 0;
  32     virtual void Visit( SmAttributNode* pNode ) = 0;
  33     virtual void Visit( SmFontNode* pNode ) = 0;
  34     virtual void Visit( SmUnHorNode* pNode ) = 0;
  35     virtual void Visit( SmBinHorNode* pNode ) = 0;
  36     virtual void Visit( SmBinVerNode* pNode ) = 0;
  37     virtual void Visit( SmBinDiagonalNode* pNode ) = 0;
  38     virtual void Visit( SmSubSupNode* pNode ) = 0;
  39     virtual void Visit( SmMatrixNode* pNode ) = 0;
  40     virtual void Visit( SmPlaceNode* pNode ) = 0;
  41     virtual void Visit( SmTextNode* pNode ) = 0;
  42     virtual void Visit( SmSpecialNode* pNode ) = 0;
  43     virtual void Visit( SmGlyphSpecialNode* pNode ) = 0;
  44     virtual void Visit( SmMathSymbolNode* pNode ) = 0;
  45     virtual void Visit( SmBlankNode* pNode ) = 0;
  46     virtual void Visit( SmErrorNode* pNode ) = 0;
  47     virtual void Visit( SmLineNode* pNode ) = 0;
  48     virtual void Visit( SmExpressionNode* pNode ) = 0;
  49     virtual void Visit( SmPolyLineNode* pNode ) = 0;
  50     virtual void Visit( SmRootNode* pNode ) = 0;
  51     virtual void Visit( SmRootSymbolNode* pNode ) = 0;
  52     virtual void Visit( SmRectangleNode* pNode ) = 0;
  53     virtual void Visit( SmVerticalBraceNode* pNode ) = 0;
  54
  55 protected:
  56     ~SmVisitor() {}
  57 };
  58
  59 // SmDefaultingVisitor
  60
  61
  62 /** Visitor that uses DefaultVisit for handling visits by default
  63  *
  64  * This abstract baseclass is useful for visitors where many methods share the same
  65  * implementation.
  66  */
  67 class SmDefaultingVisitor : public SmVisitor
  68 {
  69 public:
  70     void Visit( SmTableNode* pNode ) override;
  71     void Visit( SmBraceNode* pNode ) override;
  72     void Visit( SmBracebodyNode* pNode ) override;
  73     void Visit( SmOperNode* pNode ) override;
  74     void Visit( SmAlignNode* pNode ) override;
  75     void Visit( SmAttributNode* pNode ) override;
  76     void Visit( SmFontNode* pNode ) override;
  77     void Visit( SmUnHorNode* pNode ) override;
  78     void Visit( SmBinHorNode* pNode ) override;
  79     void Visit( SmBinVerNode* pNode ) override;
  80     void Visit( SmBinDiagonalNode* pNode ) override;
  81     void Visit( SmSubSupNode* pNode ) override;
  82     void Visit( SmMatrixNode* pNode ) override;
  83     void Visit( SmPlaceNode* pNode ) override;
  84     void Visit( SmTextNode* pNode ) override;
  85     void Visit( SmSpecialNode* pNode ) override;
  86     void Visit( SmGlyphSpecialNode* pNode ) override;
  87     void Visit( SmMathSymbolNode* pNode ) override;
  88     void Visit( SmBlankNode* pNode ) override;
  89     void Visit( SmErrorNode* pNode ) override;
  90     void Visit( SmLineNode* pNode ) override;
  91     void Visit( SmExpressionNode* pNode ) override;
  92     void Visit( SmPolyLineNode* pNode ) override;
  93     void Visit( SmRootNode* pNode ) override;
  94     void Visit( SmRootSymbolNode* pNode ) override;
  95     void Visit( SmRectangleNode* pNode ) override;
  96     void Visit( SmVerticalBraceNode* pNode ) override;
  97 protected:
  98     ~SmDefaultingVisitor() {}
  99
 100     /** Method invoked by Visit methods by default */
 101     virtual void DefaultVisit( SmNode* pNode ) = 0;
 102 };
 103
 104 // SmCaretDrawingVisitor
 105
 106 /** Visitor for drawing a caret position */
 107 class SmCaretDrawingVisitor : public SmDefaultingVisitor
 108 {
 109 public:
 110     /** Given position and device this constructor will draw the caret */
 111     SmCaretDrawingVisitor( OutputDevice& rDevice, SmCaretPos position, Point offset, bool caretVisible );
 112     virtual ~SmCaretDrawingVisitor() {}
 113     void Visit( SmTextNode* pNode ) override;
 114     using SmDefaultingVisitor::Visit;
 115 private:
 116     OutputDevice &mrDev;
 117     SmCaretPos maPos;
 118     /** Offset to draw from */
 119     Point maOffset;
 120     bool mbCaretVisible;
 121 protected:
 122     /** Default method for drawing pNodes */
 123     void DefaultVisit( SmNode* pNode ) override;
 124 };
 125
 126 // SmCaretPos2LineVisitor
 127
 128 /** Visitor getting a line from a caret position */
 129 class SmCaretPos2LineVisitor : public SmDefaultingVisitor
 130 {
 131 public:
 132     /** Given position and device this constructor will compute a line for the caret */
 133     SmCaretPos2LineVisitor( OutputDevice *pDevice, SmCaretPos position )
 134         : mpDev( pDevice )
 135         , maPos( position )
 136     {
 137         SAL_WARN_IF( !position.IsValid(), "starmath", "Cannot draw invalid position!" );
 138
 139         maPos.pSelectedNode->Accept( this );
 140     }
 141     virtual ~SmCaretPos2LineVisitor() {}
 142     void Visit( SmTextNode* pNode ) override;
 143     using SmDefaultingVisitor::Visit;
 144     const SmCaretLine& GetResult( ) {
 145         return maLine;
 146     }
 147 private:
 148     SmCaretLine maLine;
 149     VclPtr<OutputDevice> mpDev;
 150     SmCaretPos maPos;
 151 protected:
 152     /** Default method for computing lines for pNodes */
 153     void DefaultVisit( SmNode* pNode ) override;
 154 };
 155
 156 // SmDrawingVisitor
 157
 158 /** Visitor for drawing SmNodes to OutputDevice */
 159 class SmDrawingVisitor : public SmVisitor
 160 {
 161 public:
 162     /** Create an instance of SmDrawingVisitor, and use it to draw a formula
 163      * @param rDevice   Device to draw on
 164      * @param position  Offset on device to draw the formula
 165      * @param pTree     Formula tree to draw
 166      * @remarks This constructor will do the drawing, no need to anything more.
 167      */
 168     SmDrawingVisitor( OutputDevice &rDevice, Point position, SmNode* pTree )
 169         : mrDev( rDevice )
 170         , maPosition( position )
 171     {
 172         pTree->Accept( this );
 173     }
 174     virtual ~SmDrawingVisitor() {}
 175     void Visit( SmTableNode* pNode ) override;
 176     void Visit( SmBraceNode* pNode ) override;
 177     void Visit( SmBracebodyNode* pNode ) override;
 178     void Visit( SmOperNode* pNode ) override;
 179     void Visit( SmAlignNode* pNode ) override;
 180     void Visit( SmAttributNode* pNode ) override;
 181     void Visit( SmFontNode* pNode ) override;
 182     void Visit( SmUnHorNode* pNode ) override;
 183     void Visit( SmBinHorNode* pNode ) override;
 184     void Visit( SmBinVerNode* pNode ) override;
 185     void Visit( SmBinDiagonalNode* pNode ) override;
 186     void Visit( SmSubSupNode* pNode ) override;
 187     void Visit( SmMatrixNode* pNode ) override;
 188     void Visit( SmPlaceNode* pNode ) override;
 189     void Visit( SmTextNode* pNode ) override;
 190     void Visit( SmSpecialNode* pNode ) override;
 191     void Visit( SmGlyphSpecialNode* pNode ) override;
 192     void Visit( SmMathSymbolNode* pNode ) override;
 193     void Visit( SmBlankNode* pNode ) override;
 194     void Visit( SmErrorNode* pNode ) override;
 195     void Visit( SmLineNode* pNode ) override;
 196     void Visit( SmExpressionNode* pNode ) override;
 197     void Visit( SmPolyLineNode* pNode ) override;
 198     void Visit( SmRootNode* pNode ) override;
 199     void Visit( SmRootSymbolNode* pNode ) override;
 200     void Visit( SmRectangleNode* pNode ) override;
 201     void Visit( SmVerticalBraceNode* pNode ) override;
 202 private:
 203     /** Draw the children of a pNode
 204      * This the default method, use by most pNodes
 205      */
 206     void DrawChildren( SmStructureNode* pNode );
 207
 208     /** Draw an SmTextNode or a subclass of this */
 209     void DrawTextNode( SmTextNode* pNode );
 210     /** Draw an SmSpecialNode or a subclass of this  */
 211     void DrawSpecialNode( SmSpecialNode* pNode );
 212     /** OutputDevice to draw on */
 213     OutputDevice& mrDev;
 214     /** Position to draw on the mrDev
 215      * @remarks This variable is used to pass parameters in DrawChildren( ), this means
 216                 that after a call to DrawChildren( ) the contents of this method is undefined
 217                 so if needed cache it locally on the stack.
 218      */
 219     Point maPosition;
 220 };
 221
 222 // SmSetSelectionVisitor
 223
 224 /** Set Selection Visitor
 225  * Sets the IsSelected( ) property on all SmNodes of the tree
 226  */
 227 class SmSetSelectionVisitor : public SmDefaultingVisitor
 228 {
 229 public:
 230     SmSetSelectionVisitor( SmCaretPos startPos, SmCaretPos endPos, SmNode* pNode);
 231     virtual ~SmSetSelectionVisitor() {}
 232     void Visit( SmBinHorNode* pNode ) override;
 233     void Visit( SmUnHorNode* pNode ) override;
 234     void Visit( SmFontNode* pNode ) override;
 235     void Visit( SmTextNode* pNode ) override;
 236     void Visit( SmExpressionNode* pNode ) override;
 237     void Visit( SmLineNode* pNode ) override;
 238     void Visit( SmAlignNode* pNode ) override;
 239     using SmDefaultingVisitor::Visit;
 240     /** Set IsSelected on all pNodes of pSubTree */
 241     static void SetSelectedOnAll( SmNode* pSubTree, bool IsSelected = true );
 242 private:
 243     /** Visit a selectable pNode
 244      * Can be used to handle pNodes that can be selected, that doesn't have more SmCaretPos'
 245      * than 0 and 1 inside them. SmTextNode should be handle separately!
 246      * Also note that pNodes such as SmBinVerNode cannot be selected, don't this method for
 247      * it.
 248      */
 249     void DefaultVisit( SmNode* pNode ) override;
 250     void VisitCompositionNode( SmStructureNode* pNode );
 251     /** Caret position where the selection starts */
 252     SmCaretPos maStartPos;
 253     /** Caret position where the selection ends */
 254     SmCaretPos maEndPos;
 255     /** The current state of this visitor
 256      * This property changes when the visitor meets either maStartPos
 257      * or maEndPos. This means that anything visited in between will be
 258      * selected.
 259      */
 260     bool mbSelecting;
 261 };
 262
 263
 264 // SmCaretPosGraphBuildingVisitor
 265
 266
 267 /** A visitor for building a SmCaretPosGraph
 268  *
 269  * Visit invariant:
 270  * Each pNode, except SmExpressionNode, SmBinHorNode and a few others, constitutes an entry
 271  * in a line. Consider the line entry "H", this entry creates one carat position, here
 272  * denoted by | in "H|".
 273  *
 274  * Parameter variables:
 275  *  The following variables are used to transfer parameters in to calls and results out
 276  *  of calls.
 277  *      pRightMost : SmCaretPosGraphEntry*
 278  *
 279  * Prior to a Visit call:
 280  *  pRightMost: A pointer to right most position in front of the current line entry.
 281  *
 282  * After a Visit call:
 283  *  pRightMost: A pointer to the right most position in the called line entry, if no there's
 284  *              no caret positions in called line entry don't change this variable.
 285  */
 286 class SmCaretPosGraphBuildingVisitor : public SmVisitor
 287 {
 288 public:
 289     /** Builds a caret position graph for pRootNode */
 290     explicit SmCaretPosGraphBuildingVisitor( SmNode* pRootNode );
 291     virtual ~SmCaretPosGraphBuildingVisitor();
 292     void Visit( SmTableNode* pNode ) override;
 293     void Visit( SmBraceNode* pNode ) override;
 294     void Visit( SmBracebodyNode* pNode ) override;
 295     void Visit( SmOperNode* pNode ) override;
 296     void Visit( SmAlignNode* pNode ) override;
 297     void Visit( SmAttributNode* pNode ) override;
 298     void Visit( SmFontNode* pNode ) override;
 299     void Visit( SmUnHorNode* pNode ) override;
 300     void Visit( SmBinHorNode* pNode ) override;
 301     void Visit( SmBinVerNode* pNode ) override;
 302     void Visit( SmBinDiagonalNode* pNode ) override;
 303     void Visit( SmSubSupNode* pNode ) override;
 304     void Visit( SmMatrixNode* pNode ) override;
 305     void Visit( SmPlaceNode* pNode ) override;
 306     void Visit( SmTextNode* pNode ) override;
 307     void Visit( SmSpecialNode* pNode ) override;
 308     void Visit( SmGlyphSpecialNode* pNode ) override;
 309     void Visit( SmMathSymbolNode* pNode ) override;
 310     void Visit( SmBlankNode* pNode ) override;
 311     void Visit( SmErrorNode* pNode ) override;
 312     void Visit( SmLineNode* pNode ) override;
 313     void Visit( SmExpressionNode* pNode ) override;
 314     void Visit( SmPolyLineNode* pNode ) override;
 315     void Visit( SmRootNode* pNode ) override;
 316     void Visit( SmRootSymbolNode* pNode ) override;
 317     void Visit( SmRectangleNode* pNode ) override;
 318     void Visit( SmVerticalBraceNode* pNode ) override;
 319     SmCaretPosGraph* takeGraph()
 320     {
 321         return mpGraph.release();
 322     }
 323 private:
 324     SmCaretPosGraphEntry* mpRightMost;
 325     std::unique_ptr<SmCaretPosGraph> mpGraph;
 326 };
 327
 328 // SmCloningVisitor
 329
 330 /** Visitor for cloning a pNode
 331  *
 332  * This visitor creates deep clones.
 333  */
 334 class SmCloningVisitor : public SmVisitor
 335 {
 336 public:
 337     SmCloningVisitor()
 338         : mpResult(nullptr)
 339     {}
 340     virtual ~SmCloningVisitor() {}
 341     void Visit( SmTableNode* pNode ) override;
 342     void Visit( SmBraceNode* pNode ) override;
 343     void Visit( SmBracebodyNode* pNode ) override;
 344     void Visit( SmOperNode* pNode ) override;
 345     void Visit( SmAlignNode* pNode ) override;
 346     void Visit( SmAttributNode* pNode ) override;
 347     void Visit( SmFontNode* pNode ) override;
 348     void Visit( SmUnHorNode* pNode ) override;
 349     void Visit( SmBinHorNode* pNode ) override;
 350     void Visit( SmBinVerNode* pNode ) override;
 351     void Visit( SmBinDiagonalNode* pNode ) override;
 352     void Visit( SmSubSupNode* pNode ) override;
 353     void Visit( SmMatrixNode* pNode ) override;
 354     void Visit( SmPlaceNode* pNode ) override;
 355     void Visit( SmTextNode* pNode ) override;
 356     void Visit( SmSpecialNode* pNode ) override;
 357     void Visit( SmGlyphSpecialNode* pNode ) override;
 358     void Visit( SmMathSymbolNode* pNode ) override;
 359     void Visit( SmBlankNode* pNode ) override;
 360     void Visit( SmErrorNode* pNode ) override;
 361     void Visit( SmLineNode* pNode ) override;
 362     void Visit( SmExpressionNode* pNode ) override;
 363     void Visit( SmPolyLineNode* pNode ) override;
 364     void Visit( SmRootNode* pNode ) override;
 365     void Visit( SmRootSymbolNode* pNode ) override;
 366     void Visit( SmRectangleNode* pNode ) override;
 367     void Visit( SmVerticalBraceNode* pNode ) override;
 368     /** Clone a pNode */
 369     SmNode* Clone( SmNode* pNode );
 370 private:
 371     SmNode* mpResult;
 372     /** Clone children of pSource and give them to pTarget */
 373     void CloneKids( SmStructureNode* pSource, SmStructureNode* pTarget );
 374     /** Clone attributes on a pNode */
 375     static void CloneNodeAttr( SmNode const * pSource, SmNode* pTarget );
 376 };
 377
 378
 379 // SmSelectionDrawingVisitor
 380
 381 class SmSelectionDrawingVisitor : public SmDefaultingVisitor
 382 {
 383 public:
 384     /** Draws a selection on rDevice for the selection on pTree */
 385     SmSelectionDrawingVisitor( OutputDevice& rDevice, SmNode* pTree, const Point& rOffset );
 386     virtual ~SmSelectionDrawingVisitor() {}
 387     void Visit( SmTextNode* pNode ) override;
 388     using SmDefaultingVisitor::Visit;
 389 private:
 390     /** Reference to drawing device */
 391     OutputDevice& mrDev;
 392     /** True if  aSelectionArea have been initialized */
 393     bool mbHasSelectionArea;
 394     /** The current area that is selected */
 395     tools::Rectangle maSelectionArea;
 396     /** Extend the area that must be selected  */
 397     void ExtendSelectionArea(const tools::Rectangle& rArea);
 398     /** Default visiting method */
 399     void DefaultVisit( SmNode* pNode ) override;
 400     /** Visit the children of a given pNode */
 401     void VisitChildren( SmNode* pNode );
 402 };
 403
 404 // SmNodeToTextVisitor
 405
 406 /** Extract command text from pNodes */
 407 class SmNodeToTextVisitor : public SmVisitor
 408 {
 409 public:
 410     SmNodeToTextVisitor( SmNode* pNode, OUString &rText );
 411     virtual ~SmNodeToTextVisitor() {}
 412
 413     void Visit( SmTableNode* pNode ) override;
 414     void Visit( SmBraceNode* pNode ) override;
 415     void Visit( SmBracebodyNode* pNode ) override;
 416     void Visit( SmOperNode* pNode ) override;
 417     void Visit( SmAlignNode* pNode ) override;
 418     void Visit( SmAttributNode* pNode ) override;
 419     void Visit( SmFontNode* pNode ) override;
 420     void Visit( SmUnHorNode* pNode ) override;
 421     void Visit( SmBinHorNode* pNode ) override;
 422     void Visit( SmBinVerNode* pNode ) override;
 423     void Visit( SmBinDiagonalNode* pNode ) override;
 424     void Visit( SmSubSupNode* pNode ) override;
 425     void Visit( SmMatrixNode* pNode ) override;
 426     void Visit( SmPlaceNode* pNode ) override;
 427     void Visit( SmTextNode* pNode ) override;
 428     void Visit( SmSpecialNode* pNode ) override;
 429     void Visit( SmGlyphSpecialNode* pNode ) override;
 430     void Visit( SmMathSymbolNode* pNode ) override;
 431     void Visit( SmBlankNode* pNode ) override;
 432     void Visit( SmErrorNode* pNode ) override;
 433     void Visit( SmLineNode* pNode ) override;
 434     void Visit( SmExpressionNode* pNode ) override;
 435     void Visit( SmPolyLineNode* pNode ) override;
 436     void Visit( SmRootNode* pNode ) override;
 437     void Visit( SmRootSymbolNode* pNode ) override;
 438     void Visit( SmRectangleNode* pNode ) override;
 439     void Visit( SmVerticalBraceNode* pNode ) override;
 440 private:
 441     /** Extract text from a pNode that constitutes a line */
 442     void LineToText( SmNode* pNode ) {
 443         Separate( );
 444         if( pNode )
 445             pNode->Accept( this );
 446         Separate( );
 447     }
 448     void Append( const OUString &rText ) {
 449         maCmdText.append( rText );
 450     }
 451     /** Append a blank for separation, if needed */
 452     void Separate( ){
 453         if( maCmdText.isEmpty() || maCmdText[ maCmdText.getLength() - 1 ] != ' ' )
 454             maCmdText.append(' ');
 455     }
 456     /** Output text generated from the pNodes */
 457     OUStringBuffer maCmdText;
 458 };
 459
 460 #endif // INCLUDED_STARMATH_INC_VISITORS_HXX
 461
 462 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */