diff options
Diffstat (limited to '')
| -rw-r--r-- | starmath/inc/cursor.hxx | 427 |
1 files changed, 427 insertions, 0 deletions
diff --git a/starmath/inc/cursor.hxx b/starmath/inc/cursor.hxx new file mode 100644 index 000000000..236485d5e --- /dev/null +++ b/starmath/inc/cursor.hxx @@ -0,0 +1,427 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + */ +#ifndef INCLUDED_STARMATH_INC_CURSOR_HXX +#define INCLUDED_STARMATH_INC_CURSOR_HXX + +#include "node.hxx" +#include "caret.hxx" + +#include <cassert> +#include <list> +#include <memory> + +/** Factor to multiple the squared horizontal distance with + * Used for Up and Down movement. + */ +#define HORIZONTICAL_DISTANCE_FACTOR 10 + +/** Enum of direction for movement */ +enum SmMovementDirection{ + MoveUp, + MoveDown, + MoveLeft, + MoveRight +}; + +/** Enum of elements that can inserted into a formula */ +enum SmFormulaElement{ + BlankElement, + FactorialElement, + PlusElement, + MinusElement, + CDotElement, + EqualElement, + LessThanElement, + GreaterThanElement, + PercentElement +}; + +/** Bracket types that can be inserted */ +enum class SmBracketType { + /** Round brackets, left command "(" */ + Round, + /**Square brackets, left command "[" */ + Square, + /** Curly brackets, left command "lbrace" */ + Curly, +}; + +/** A list of nodes */ +typedef std::list<SmNode*> SmNodeList; + +typedef std::list<std::unique_ptr<SmNode>> SmClipboard; + +class SmDocShell; + +/** Formula cursor + * + * This class is used to represent a cursor in a formula, which can be used to manipulate + * a formula programmatically. + * @remarks This class is a very intimate friend of SmDocShell. + */ +class SmCursor{ +public: + SmCursor(SmNode* tree, SmDocShell* pShell) + : mpAnchor(nullptr) + , mpPosition(nullptr) + , mpTree(tree) + , mpDocShell(pShell) + , mnEditSections(0) + , mbIsEnabledSetModifiedSmDocShell(false) + { + //Build graph + BuildGraph(); + } + + /** Get position */ + const SmCaretPos& GetPosition() const { return mpPosition->CaretPos; } + + /** True, if the cursor has a selection */ + bool HasSelection() const { return mpAnchor != mpPosition; } + + /** Move the position of this cursor */ + void Move(OutputDevice* pDev, SmMovementDirection direction, bool bMoveAnchor = true); + + /** Move to the caret position closest to a given point */ + void MoveTo(OutputDevice* pDev, const Point& pos, bool bMoveAnchor); + + /** Delete the current selection or do nothing */ + void Delete(); + + /** Delete selection, previous element or merge lines + * + * This method implements the behaviour of backspace. + */ + void DeletePrev(OutputDevice* pDev); + + /** Insert text at the current position */ + void InsertText(const OUString& aString); + + /** Insert an element into the formula */ + void InsertElement(SmFormulaElement element); + + /** Insert command text translated into line entries at position + * + * Note: This method uses the parser to translate a command text into a + * tree, then it copies line entries from this tree into the current tree. + * Will not work for commands such as newline or ##, if position is in a matrix. + * This will work for stuff like "A intersection B". But stuff spanning multiple lines + * or dependent on the context which position is placed in will not work! + */ + void InsertCommandText(const OUString& aCommandText); + + /** Insert a special node created from aString + * + * Used for handling insert request from the "catalog" dialog. + * The provided string should be formatted as the desired command: %phi + * Note: this method ONLY supports commands defined in Math.xcu + * + * For more complex expressions use InsertCommandText, this method doesn't + * use SmParser, this means that it's faster, but not as strong. + */ + void InsertSpecial(const OUString& aString); + + /** Create sub-/super script + * + * If there's a selection, it will be move into the appropriate sub-/super scription + * of the node in front of it. If there's no node in front of position (or the selection), + * a sub-/super scription of a new SmPlaceNode will be made. + * + * If there's is an existing subscription of the node, the caret will be moved into it, + * and any selection will replace it. + */ + void InsertSubSup(SmSubSup eSubSup); + + /** Insert a new row or newline + * + * Inserts a new row if position is in a matrix or stack command. + * Otherwise a newline is inserted if we're in a toplevel line. + * + * @returns True, if a new row/line could be inserted. + * + * @remarks If the caret is placed in a subline of a command that doesn't support + * this operator the method returns FALSE, and doesn't do anything. + */ + bool InsertRow(); + + /** Insert a fraction, use selection as numerator */ + void InsertFraction(); + + /** Create brackets around current selection, or new SmPlaceNode */ + void InsertBrackets(SmBracketType eBracketType); + + /** Copy the current selection */ + void Copy(); + /** Cut the current selection */ + void Cut(){ + Copy(); + Delete(); + } + /** Paste the clipboard */ + void Paste(); + + /** Returns true if more than one node is selected + * + * This method is used for implementing backspace and delete. + * If one of these causes a complex selection, e.g. a node with + * subnodes or similar, this should not be deleted immediately. + */ + bool HasComplexSelection(); + + /** Finds the topmost node in a visual line + * + * If MoveUpIfSelected is true, this will move up to the parent line + * if the parent of the current line is selected. + */ + static SmNode* FindTopMostNodeInLine(SmNode* pSNode, bool MoveUpIfSelected = false); + + /** Draw the caret */ + void Draw(OutputDevice& pDev, Point Offset, bool isCaretVisible); + + bool IsAtTailOfBracket(SmBracketType eBracketType, SmBraceNode** ppBraceNode) const; + void MoveAfterBracket(SmBraceNode* pBraceNode); + +private: + friend class SmDocShell; + + SmCaretPosGraphEntry *mpAnchor, + *mpPosition; + /** Formula tree */ + SmNode* mpTree; + /** Owner of the formula tree */ + SmDocShell* mpDocShell; + /** Graph over caret position in the current tree */ + std::unique_ptr<SmCaretPosGraph> mpGraph; + /** Clipboard holder */ + SmClipboard maClipboard; + + /** Returns a node that is selected, if any could be found */ + SmNode* FindSelectedNode(SmNode* pNode); + + /** Is this one of the nodes used to compose a line + * + * These are SmExpression, SmBinHorNode, SmUnHorNode etc. + */ + static bool IsLineCompositionNode(SmNode const * pNode); + + /** Count number of selected nodes, excluding line composition nodes + * + * Note this function doesn't count line composition nodes and it + * does count all subnodes as well as the owner nodes. + * + * Used by SmCursor::HasComplexSelection() + */ + int CountSelectedNodes(SmNode* pNode); + + /** Convert a visual line to a list + * + * Note this method will delete all the nodes that will no longer be needed. + * that includes pLine! + * This method also deletes SmErrorNode's as they're just meta info in the line. + */ + static void LineToList(SmStructureNode* pLine, SmNodeList& rList); + + /** Auxiliary function for calling LineToList on a node + * + * This method sets pNode = NULL and remove it from its parent. + * (Assuming it has a parent, and is a child of it). + */ + static void NodeToList(SmNode*& rpNode, SmNodeList& rList){ + //Remove from parent and NULL rpNode + SmNode* pNode = rpNode; + if(rpNode && rpNode->GetParent()){ //Don't remove this, correctness relies on it + int index = rpNode->GetParent()->IndexOfSubNode(rpNode); + assert(index >= 0); + rpNode->GetParent()->SetSubNode(index, nullptr); + } + rpNode = nullptr; + //Create line from node + if(pNode && IsLineCompositionNode(pNode)){ + LineToList(static_cast<SmStructureNode*>(pNode), rList); + return; + } + if(pNode) + rList.push_front(pNode); + } + + /** Clone a visual line to a clipboard + * + * ... but the selected part only. + * Doesn't clone SmErrorNodes, which are ignored as they are context dependent metadata. + */ + static void CloneLineToClipboard(SmStructureNode* pLine, SmClipboard* pClipboard); + + /** Build pGraph over caret positions */ + void BuildGraph(); + + /** Insert new nodes in the tree after position */ + void InsertNodes(std::unique_ptr<SmNodeList> pNewNodes); + + /** tries to set position to a specific SmCaretPos + * + * @returns false on failure to find the position in pGraph. + */ + bool SetCaretPosition(SmCaretPos pos); + + /** Set selected on nodes of the tree */ + void AnnotateSelection(); + + /** Clone list of nodes in a clipboard (creates a deep clone) */ + static std::unique_ptr<SmNodeList> CloneList(SmClipboard &rClipboard); + + /** Find an iterator pointing to the node in pLineList following rCaretPos + * + * If rCaretPos.pSelectedNode cannot be found it is assumed that it's in front of pLineList, + * thus not an element in pLineList. In this case this method returns an iterator to the + * first element in pLineList. + * + * If the current position is inside an SmTextNode, this node will be split in two, for this + * reason you should beaware that iterators to elements in pLineList may be invalidated, and + * that you should call PatchLineList() with this iterator if no action is taken. + */ + static SmNodeList::iterator FindPositionInLineList(SmNodeList* pLineList, + const SmCaretPos& rCaretPos); + + /** Patch a line list after modification, merge SmTextNode, remove SmPlaceNode etc. + * + * @param pLineList The line list to patch + * @param aIter Iterator pointing to the element that needs to be patched with its previous. + * + * When the list is patched text nodes before and after aIter will be merged. + * If there's an, in the context, inappropriate SmPlaceNode before or after aIter it will also be + * removed. + * + * @returns A caret position equivalent to one selecting the node before aIter, the method returns + * an invalid SmCaretPos to indicate placement in front of the line. + */ + static SmCaretPos PatchLineList(SmNodeList* pLineList, SmNodeList::iterator aIter); + + /** Take selected nodes from a list + * + * Puts the selected nodes into pSelectedNodes, or if pSelectedNodes is NULL deletes + * the selected nodes. + * Note: If there's a selection inside an SmTextNode this node will be split, and it + * will not be merged when the selection have been taken. Use PatchLineList on the + * iterator returns to fix this. + * + * @returns An iterator pointing to the element following the selection taken. + */ + static SmNodeList::iterator TakeSelectedNodesFromList(SmNodeList *pLineList, + SmNodeList *pSelectedNodes = nullptr); + + /** Create an instance of SmMathSymbolNode usable for brackets */ + static SmNode *CreateBracket(SmBracketType eBracketType, bool bIsLeft); + + /** The number of times BeginEdit have been called + * Used to allow nesting of BeginEdit() and EndEdit() sections + */ + int mnEditSections; + /** Holds data for BeginEdit() and EndEdit() */ + bool mbIsEnabledSetModifiedSmDocShell; + /** Begin edit section where the tree will be modified */ + void BeginEdit(); + /** End edit section where the tree will be modified */ + void EndEdit(); + /** Finish editing + * + * Finishes editing by parsing pLineList and inserting back into pParent at nParentIndex. + * This method also rebuilds the graph, annotates the selection, sets caret position and + * Calls EndEdit. + * + * @remarks Please note that this method will delete pLineList, as the elements are taken. + * + * @param pLineList List the constitutes the edited line. + * @param pParent Parent to which the line should be inserted. + * @param nParentIndex Index in parent where the line should be inserted. + * @param PosAfterEdit Caret position to look for after rebuilding graph. + * @param pStartLine Line to take first position in, if PosAfterEdit cannot be found, + * leave it NULL for pLineList. + */ + void FinishEdit(std::unique_ptr<SmNodeList> pLineList, + SmStructureNode* pParent, + int nParentIndex, + SmCaretPos PosAfterEdit, + SmNode* pStartLine = nullptr); + /** Request the formula is repainted */ + void RequestRepaint(); +}; + +/** Minimalistic recursive decent SmNodeList parser + * + * This parser is used to take a list of nodes that constitutes a line + * and parse them to a tree of SmBinHorNode, SmUnHorNode and SmExpression. + * + * Please note, this will not handle all kinds of nodes, only nodes that + * constitutes and entry in a line. + * + * Below is an EBNF representation of the grammar used for this parser: + * \code + * Expression -> Relation* + * Relation -> Sum [(=|<|>|...) Sum]* + * Sum -> Product [(+|-) Product]* + * Product -> Factor [(*|/) Factor]* + * Factor -> [+|-|-+|...]* Factor | Postfix + * Postfix -> node [!]* + * \endcode + */ +class SmNodeListParser{ +public: + /** Create an instance of SmNodeListParser */ + SmNodeListParser(){ + pList = nullptr; + } + /** Parse a list of nodes to an expression. + * + * Old error nodes will be deleted. + */ + SmNode* Parse(SmNodeList* list); + /** True, if the token is an operator */ + static bool IsOperator(const SmToken &token); + /** True, if the token is a relation operator */ + static bool IsRelationOperator(const SmToken &token); + /** True, if the token is a sum operator */ + static bool IsSumOperator(const SmToken &token); + /** True, if the token is a product operator */ + static bool IsProductOperator(const SmToken &token); + /** True, if the token is a unary operator */ + static bool IsUnaryOperator(const SmToken &token); + /** True, if the token is a postfix operator */ + static bool IsPostfixOperator(const SmToken &token); +private: + SmNodeList* pList; + /** Get the current terminal */ + SmNode* Terminal(){ + if (!pList->empty()) + return pList->front(); + return nullptr; + } + /** Move to next terminal */ + SmNode* Next(){ + pList->pop_front(); + return Terminal(); + } + /** Take the current terminal */ + SmNode* Take(){ + SmNode* pRetVal = Terminal(); + Next(); + return pRetVal; + } + SmNode* Expression(); + SmNode* Relation(); + SmNode* Sum(); + SmNode* Product(); + SmNode* Factor(); + SmNode* Postfix(); + static SmNode* Error(); +}; + + +#endif // INCLUDED_STARMATH_INC_CURSOR_HXX + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |