formulacursor.cpp

/* This file is part of the KDE project
   Copyright (C) 2001 Andrea Rizzi <rizzi@kde.org>
                  Ulrich Kuettler <ulrich.kuettler@mailbox.tu-dresden.de>
 
   This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.
 
   This library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.
 
   You should have received a copy of the GNU Library General Public License
   along with this library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
*/
 
#include <tqpainter.h>
 
#include <kdebug.h>
#include <assert.h>
 
#include "formulacursor.h"
#include "formulaelement.h"
#include "indexelement.h"
#include "matrixelement.h"
#include "rootelement.h"
#include "sequenceelement.h"
#include "symbolelement.h"
#include "textelement.h"
 
KFORMULA_NAMESPACE_BEGIN
 
FormulaCursor::FormulaCursor(FormulaElement* element)
        : selectionFlag(false), linearMovement(false),
          hasChangedFlag(true), readOnly(false)
{
    //setTo(element, 0);
    element->goInside( this );
}
 
void FormulaCursor::setTo(BasicElement* element, uint cursor, int mark)
{
    hasChangedFlag = true;
    current = element;
    cursorPos = cursor;
    if ((mark == -1) && selectionFlag) {
        return;
    }
    if (mark != -1) {
        setSelection(true);
    }
    markPos = mark;
}
 
 
void FormulaCursor::setPos(uint pos)
{
    hasChangedFlag = true;
    cursorPos = pos;
}
 
void FormulaCursor::setMark(int mark)
{
    hasChangedFlag = true;
    markPos = mark;
}
 
void FormulaCursor::calcCursorSize( const ContextStyle& context, bool smallCursor )
{
    // We only draw the cursor if its normalized.
    SequenceElement* sequence = dynamic_cast<SequenceElement*>(current);
 
    if (sequence != 0) {
        sequence->calcCursorSize( context, this, smallCursor );
    }
}
 
void FormulaCursor::draw( TQPainter& painter, const ContextStyle& context, 
                          StyleAttributes& style, bool smallCursor, bool activeCursor )
{
    //if (readOnly && !isSelection())
    //return;
 
    // We only draw the cursor if its normalized.
    SequenceElement* sequence = dynamic_cast<SequenceElement*>(current);
 
    if (sequence != 0) {
        sequence->drawCursor( painter, context, style, this, smallCursor, activeCursor );
    }
}
 
 
void FormulaCursor::handleSelectState(int flag)
{
    if (flag & SelectMovement) {
        if (!isSelection()) {
            setMark(getPos());
            setSelection(true);
        }
    }
    else {
        setSelection(false);
    }
}
 
void FormulaCursor::moveLeft(int flag)
{
    BasicElement* element = getElement();
    handleSelectState(flag);
    if (flag & WordMovement) {
        SequenceElement* sequence = dynamic_cast<SequenceElement*>(current);
        if (sequence != 0) {
            sequence->moveWordLeft(this);
        }
        else {
            element->moveHome(this);
        }
    }
    else {
        element->moveLeft(this, element);
    }
}
 
void FormulaCursor::moveRight(int flag)
{
    BasicElement* element = getElement();
    handleSelectState(flag);
    if (flag & WordMovement) {
        SequenceElement* sequence = dynamic_cast<SequenceElement*>(current);
        if (sequence != 0) {
            sequence->moveWordRight(this);
        }
        else {
            element->moveEnd(this);
        }
    }
    else {
        element->moveRight(this, element);
    }
}
 
void FormulaCursor::moveUp(int flag)
{
    BasicElement* element = getElement();
    handleSelectState(flag);
    element->moveUp(this, element);
}
 
void FormulaCursor::moveDown(int flag)
{
    BasicElement* element = getElement();
    handleSelectState(flag);
    element->moveDown(this, element);
}
 
void FormulaCursor::moveHome(int flag)
{
    BasicElement* element = getElement();
    handleSelectState(flag);
    if (flag & WordMovement) {
        element->formula()->moveHome(this);
    }
    else {
        element->moveHome(this);
    }
}
 
void FormulaCursor::moveEnd(int flag)
{
    BasicElement* element = getElement();
    handleSelectState(flag);
    if (flag & WordMovement) {
        element->formula()->moveEnd(this);
    }
    else {
        element->moveEnd(this);
    }
}
 
bool FormulaCursor::isHome() const
{
    return ( getElement() == getElement()->formula() ) && ( getPos() == 0 );
}
 
bool FormulaCursor::isEnd() const
{
    return ( getElement() == getElement()->formula() ) &&
                  ( getPos() == normal()->countChildren() );
}
 
void FormulaCursor::mousePress( const LuPixelPoint& pos, int flag )
{
    FormulaElement* formula = getElement()->formula();
    formula->goToPos( this, pos );
    if (flag & SelectMovement) {
        setSelection(true);
        if (getMark() == -1) {
            setMark(getPos());
        }
    }
    else {
        setSelection(false);
        setMark(getPos());
    }
}
 
void FormulaCursor::mouseMove( const LuPixelPoint& point, int )
{
    setSelection(true);
    BasicElement* element = getElement();
    int mark = getMark();
 
    FormulaElement* formula = getElement()->formula();
    formula->goToPos( this, point );
    BasicElement* newElement = getElement();
    int pos = getPos();
 
    BasicElement* posChild = 0;
    BasicElement* markChild = 0;
    while (element != newElement) {
        posChild = newElement;
        newElement = newElement->getParent();
        if (newElement == 0) {
            posChild = 0;
            newElement = getElement();
            markChild = element;
            element = element->getParent();
        }
    }
 
    if (dynamic_cast<SequenceElement*>(element) == 0) {
        element = element->getParent();
        element->selectChild(this, newElement);
    }
    else {
        if (posChild != 0) {
            element->selectChild(this, posChild);
            pos = getPos();
        }
        if (markChild != 0) {
            element->selectChild(this, markChild);
            mark = getMark();
        }
        if (pos == mark) {
            if ((posChild == 0) && (markChild != 0)) {
                mark++;
            }
            else if ((posChild != 0) && (markChild == 0)) {
                mark--;
            }
        }
        else if (pos < mark) {
            if (posChild != 0) {
                pos--;
            }
        }
        setTo(element, pos, mark);
    }
}
 
void FormulaCursor::mouseRelease( const LuPixelPoint&, int )
{
    //mouseSelectionFlag = false;
}
 

void FormulaCursor::goInsideElement(BasicElement* element)
{
    element->goInside(this);
}
 

void FormulaCursor::normalize(Direction direction)
{
    BasicElement* element = getElement();
    element->normalize(this, direction);
}
 

void FormulaCursor::insert(BasicElement* child, Direction direction)
{
    TQPtrList<BasicElement> list;
    list.append(child);
    insert(list, direction);
}
 
void FormulaCursor::insert(TQPtrList<BasicElement>& children,
                           Direction direction)
{
    assert( !isReadOnly() );
    BasicElement* element = getElement();
    element->insert(this, children, direction);
}
 

void FormulaCursor::remove(TQPtrList<BasicElement>& children,
                           Direction direction)
{
    assert( !isReadOnly() );
    SequenceElement* sequence = normal();
    if (sequence != 0) {
 
        // If there is no child to remove in the sequence
        // remove the sequence instead.
        if (sequence->countChildren() == 0) {
            BasicElement* parent = sequence->getParent();
            if (parent != 0) {
                parent->selectChild(this, sequence);
                parent->remove(this, children, direction);
                return;
            }
        }
        else {
            sequence->remove(this, children, direction);
        }
    }
}
 

void FormulaCursor::replaceSelectionWith(BasicElement* element,
                                         Direction direction)
{
    assert( !isReadOnly() );
    TQPtrList<BasicElement> list;
    // we suppres deletion here to get an error if something
    // was left in the list.
    //list.setAutoDelete(true);
 
    //remove(list, direction);
    if (isSelection()) {
        getElement()->remove(this, list, direction);
    }
 
    insert(element, direction);
    SequenceElement* mainChild = element->getMainChild();
    if (mainChild != 0) {
        mainChild->goInside(this);
        insert(list);
        /*
        BasicElement* parent = element->getParent();
        if (direction == beforeCursor) {
            parent->moveRight(this, element);
        }
        else {
            parent->moveLeft(this, element);
        }
        */
        element->selectChild(this, mainChild);
    }
}
 

BasicElement* FormulaCursor::replaceByMainChildContent(Direction direction)
{
    assert( !isReadOnly() );
    TQPtrList<BasicElement> childrenList;
    TQPtrList<BasicElement> list;
    BasicElement* element = getElement();
    SequenceElement* mainChild = element->getMainChild();
    if ((mainChild != 0) && (mainChild->countChildren() > 0)) {
        mainChild->selectAllChildren(this);
        remove(childrenList);
    }
    element->getParent()->selectChild(this, element);
    setSelection(false);
    remove(list);
    insert(childrenList, direction);
    if (list.count() > 0) {
        return list.take(0);
    }
    return 0;
}
 

BasicElement* FormulaCursor::removeEnclosingElement(Direction direction)
{
    assert( !isReadOnly() );
    BasicElement* parent = getElement()->getParent();
    if (parent != 0) {
        if (getElement() == parent->getMainChild()) {
            parent->selectChild(this, getElement());
            return replaceByMainChildContent(direction);
        }
    }
    return 0;
}
 

bool FormulaCursor::elementIsSenseless()
{
    BasicElement* element = getElement();
    return element->isSenseless();
}
 

BasicElement* FormulaCursor::getActiveChild(Direction direction)
{
    return getElement()->getChild(this, direction);
}
 
BasicElement* FormulaCursor::getSelectedChild()
{
    if (isSelection()) {
        if ((getSelectionEnd() - getSelectionStart()) > 1) {
            return 0;
        }
        return getActiveChild((getPos() > getMark()) ?
                              beforeCursor :
                              afterCursor);
    }
    else {
        return getActiveChild(beforeCursor);
    }
}
 
 
void FormulaCursor::selectActiveElement()
{
    if ( !isSelection() && getPos() > 0 ) {
        setSelection( true );
        setMark( getPos() - 1 );
    }
}
 

bool FormulaCursor::pointsAfterMainChild(BasicElement* element)
{
    if (element != 0) {
        SequenceElement* mainChild = element->getMainChild();
        return (getElement() == mainChild) &&
            ((mainChild->countChildren() == getPos()) || (0 == getPos()));
    }
    return false;
}
 

IndexElement* FormulaCursor::getActiveIndexElement()
{
    IndexElement* element = dynamic_cast<IndexElement*>(getSelectedChild());
 
    if ((element == 0) && !isSelection()) {
        element = dynamic_cast<IndexElement*>(getElement()->getParent());
        if (!pointsAfterMainChild(element)) {
            return 0;
        }
    }
    return element;
}
 

RootElement* FormulaCursor::getActiveRootElement()
{
    RootElement* element = dynamic_cast<RootElement*>(getSelectedChild());
 
    if ((element == 0) && !isSelection()) {
        element = dynamic_cast<RootElement*>(getElement()->getParent());
        if (!pointsAfterMainChild(element)) {
            return 0;
        }
    }
    return element;
}
 

SymbolElement* FormulaCursor::getActiveSymbolElement()
{
    SymbolElement* element = dynamic_cast<SymbolElement*>(getSelectedChild());
 
    if ((element == 0) && !isSelection()) {
        element = dynamic_cast<SymbolElement*>(getElement()->getParent());
        if (!pointsAfterMainChild(element)) {
            return 0;
        }
    }
    return element;
}

NameSequence* FormulaCursor::getActiveNameSequence()
{
    NameSequence* element = dynamic_cast<NameSequence*>( getSelectedChild() );
 
    if ( ( element == 0 ) && !isSelection() ) {
        element = dynamic_cast<NameSequence*>( getElement() );
        if ( !pointsAfterMainChild( element ) ) {
            return 0;
        }
    }
    return element;
}

TextElement* FormulaCursor::getActiveTextElement()
{
    return dynamic_cast<TextElement*>(getSelectedChild());
}
 
 
MatrixElement* FormulaCursor::getActiveMatrixElement()
{
    MatrixElement* element = dynamic_cast<MatrixElement*>(getSelectedChild());
 
    if ( ( element != 0 ) && !isSelection() ) {
        normal()->selectChild( this, element );
    }
//     if ((element == 0) && !isSelection()) {
//         element = dynamic_cast<MatrixElement*>(getElement()->getParent());
//         if (!pointsAfterMainChild(element)) {
//             return 0;
//         }
//     }
    return element;
}

void FormulaCursor::elementWillVanish(BasicElement* element)
{
    BasicElement* child = getElement();
    if (element && child == element->getParent()) {
        child->childWillVanish(this, element);
        return;
    }
    while (child != 0) {
        if (child == element) {
            // This is meant to catch all cursors that did not
            // cause the deletion.
            child->getParent()->moveLeft(this, child);
            setSelection(false);
            hasChangedFlag = true;
            return;
        }
        child = child->getParent();
    }
}
 

void FormulaCursor::formulaLoaded(FormulaElement* rootElement)
{
    //current = rootElement;
    //setPos(0);
    rootElement->goInside( this );
    setMark(-1);
    setSelection(false);
}
 
 
bool FormulaCursor::isReadOnly() const
{
    if ( readOnly ) {
        return true;
    }
    const SequenceElement* sequence = normal();
    if ( sequence != 0 ) {
        bool ro = sequence->readOnly( this );
        //kdDebug() << k_funcinfo << "readOnly=" << ro << endl;
        return ro;
    }
    return false;
}
 

void FormulaCursor::copy( TQDomDocument& doc )
{
    if (isSelection()) {
        SequenceElement* sequence = normal();
        if (sequence != 0) {
            TQDomElement root = doc.createElementNS( "http://www.w3.org/1998/Math/MathML",
                                                    "math" );
            doc.appendChild( root );
            TQDomElement de = doc.createElement( "mrow" );
            root.appendChild( de );
            sequence->getChildrenMathMLDom(doc, de, getSelectionStart(), getSelectionEnd());
        }
        else {
            // This must never happen.
            tqFatal("A not normalized cursor is selecting.");
        }
    }
}

bool FormulaCursor::buildElementsFromDom( TQDomElement root, TQPtrList<BasicElement>& list )
{
    assert( !isReadOnly() );
    SequenceElement* sequence = normal();
    if (sequence != 0) {
        TQDomElement e = root.firstChild().toElement();
        if (sequence->buildChildrenFromDom(list, e.firstChild())) {
            return true;
        }
    }
    return false;
}

bool FormulaCursor::buildElementsFromMathMLDom( TQDomElement root, TQPtrList<BasicElement>& list )
{
    assert( !isReadOnly() );
    SequenceElement* sequence = normal();
    if (sequence != 0) {
        TQDomElement e = root.firstChild().toElement();
        if (sequence->buildChildrenFromMathMLDom(list, e.firstChild())) {
            return true;
        }
    }
    return false;
}

FormulaCursor::CursorData* FormulaCursor::getCursorData()
{
    return new CursorData(current, cursorPos, markPos,
                          selectionFlag, linearMovement, readOnly);
}
 
 
// Keep in sync with 'setCursorData'
FormulaCursor& FormulaCursor::operator= (const FormulaCursor& other)
{
    current = other.current;
    cursorPos = other.cursorPos;
    markPos = other.markPos;
    selectionFlag = other.selectionFlag;
    linearMovement = other.linearMovement;
    readOnly = other.readOnly;
    hasChangedFlag = true;
    return *this;
}
 

void FormulaCursor::setCursorData(FormulaCursor::CursorData* data)
{
    current = data->current;
    cursorPos = data->cursorPos;
    markPos = data->markPos;
    selectionFlag = data->selectionFlag;
    linearMovement = data->linearMovement;
    readOnly = data->readOnly;
    hasChangedFlag = true;
}
 

SequenceElement* FormulaCursor::normal()
{
    return dynamic_cast<SequenceElement*>(current);
}
 
const SequenceElement* FormulaCursor::normal() const
{
    return dynamic_cast<SequenceElement*>(current);
}
 
KFORMULA_NAMESPACE_END