#include "latexcompleter.h"
#include "latexcompleter_p.h"
#include "latexcompleter_config.h"
#include "help.h"
#include "usermacro.h"

#include "smallUsefulFunctions.h"

#include "qdocumentline.h"
#include "qdocument_p.h"
#include "qeditorinputbinding.h"
#include "qformatfactory.h"
#include "qdocumentline_p.h"

#include "latexdocument.h"
#include "latexeditorview.h"
#include "qdocument.h"

#include <algorithm>
#include <QtConcurrentFilter>
#include <QtConcurrentMap>


//------------------------------Default Input Binding--------------------------------
class CompleterInputBinding: public QEditorInputBinding
{
public:
    CompleterInputBinding(): active(false), showAlways(false), showMostUsed(0), completer(nullptr), editor(nullptr), oldBinding(nullptr), curStart(0), maxWritten(0), curLineNumber(0) {}
	virtual QString id() const
	{
		return "TXS::CompleterInputBinding";
	}
	virtual QString name() const
	{
		return "TXS::CompleterInputBinding";
	}

	virtual bool mousePressEvent(QMouseEvent *mouse, QEditor *editor)
	{
		// remove unused argument warnings
		Q_UNUSED(mouse)
		Q_UNUSED(editor)
		simpleRestoreAutoOverride();
		resetBinding();
		return false;
	}

	QString getCurWord()
	{
		if (!editor) return QString();
		//QMessageBox::information(0,curLine.text().mid(curStart,editor->cursor().columnNumber()-curStart),"",0);
		return editor->text(curLineNumber).mid(curStart, editor->cursor().columnNumber() - curStart);
	}

    /// check if current cursor/placeholder is mirrored
	bool isMirrored()
	{
		if (!editor) return false;
		if ( editor->currentPlaceHolder() >= 0 && editor->currentPlaceHolder() < editor->placeHolderCount() ) {
			PlaceHolder ph = editor->getPlaceHolder(editor->currentPlaceHolder());
			return ph.mirrors.count() > 0;
		}
		return false;
	}

	void insertText(const QString &text)
	{
		if (!editor) return;
		maxWritten += text.length();
        bool macroing = false;
        if ( editor->currentPlaceHolder() >= 0 && editor->currentPlaceHolder() < editor->placeHolderCount() ){
            macroing=true;
            editor->document()->beginMacro();
        }
        editor->write(text);
        //cursor mirrors
		if ( editor->currentPlaceHolder() >= 0 && editor->currentPlaceHolder() < editor->placeHolderCount() ) {
			PlaceHolder ph = editor->getPlaceHolder(editor->currentPlaceHolder());

			QString baseText = ph.cursor.selectedText();

			for ( int phm = 0; phm < ph.mirrors.count(); ++phm ) {
				//QString s = ph.affector ?  ph.affector->affect(text, baseText, m_curPlaceHolder, phm) : baseText;

				ph.mirrors[phm].replaceSelectedText(baseText);
			}
        }
        if(macroing)
            editor->document()->endMacro();
		//end cursor mirrors
		if (editor->cursor().columnNumber() > curStart + 1 && !completer->isVisible()) {
			QString wrd = getCurWord();
			completer->filterList(wrd, showMostUsed);
			completer->widget->show();
            completer->widget->raise();
			if (showMostUsed == 1 && completer->countWords() == 0) { // if prefered list is empty, take next more extensive one
                completer->setTab(0); // typical
			}
			if (showMostUsed == 0 && completer->countWords() == 0) {
                completer->setTab(3); // all
			}
			completer->adjustWidget();
		}
	}

	bool insertCompletedWord()
	{
		if (!editor) return false;
		if (completer->list->isVisible() && maxWritten >= curStart && completer->list->currentIndex().isValid()) {
			QDocumentCursor cursor = editor->cursor();
			QVariant v = completer->list->model()->data(completer->list->currentIndex(), Qt::DisplayRole);
			if (!v.isValid() || !v.canConvert<CompletionWord>()) return false;
            editor->document()->beginMacro();
			CompletionWord cw = v.value<CompletionWord>();
			completer->listModel->incUsage(completer->list->currentIndex());
			//int alreadyWrittenLen=editor->cursor().columnNumber()-curStart;
			//remove current text for correct case
			if (completer->forcedRef) {
				QString line = cursor.line().text();
				int col = cursor.columnNumber();
				bool missingCloseBracket = (findClosingBracket(line, col) < 0);
				QString eow = "}],";
				while (!cursor.atLineEnd() && !eow.contains(cursor.nextChar())
				        && !(cursor.nextChar().isSpace() && missingCloseBracket)) { // spaces are allowed in labels and should be deleted, however we stop deleting at spaces if the closing bracket is missing. otherwise it deletes the complete line.
					cursor.deleteChar();
				}
				//if(cursor.nextChar()=='}')
				//	cursor.deleteChar();
			}
			if (completer->forcedCite) {
				QString line = cursor.line().text();
				int col = cursor.columnNumber();
				bool missingCloseBracket = (findClosingBracket(line, col) < 0);
				QString eow = "},";
				while (!cursor.atLineEnd() && !eow.contains(cursor.nextChar())
				        && !(cursor.nextChar().isSpace() && missingCloseBracket))
					cursor.deleteChar();
			}
			if (isMirrored() && (cw.lines.first().startsWith("\\begin") || cw.lines.first().startsWith("\\end"))) {
				QString text = cw.lines.first();
				int i = cursor.columnNumber() - curStart;
				text.remove(0, i);
				i = text.indexOf('}');
				if (i >= 0)
					text.remove(i, text.length());
				while (!cursor.atLineEnd() && cursor.nextChar() != '}') {
					cursor.deleteChar();
				}
				insertText(text);
				editor->document()->endMacro();
				return true;
			}
            // check whether cursor is inside math in case of automatic delimter insertion
            // this is done here as the charcter format is used for detection and here we are sure that at least 1 character was used.
            QString cwCmd=cw.word;
            QRegularExpression rx("\\\\[a-zA-Z]+");
            QRegularExpressionMatch rxm=rx.match(cwCmd);
            if(rxm.hasMatch()){
                cwCmd=rxm.captured(0);
            }
            bool inMath=false;
            bool isPotentialMathCommand=(cw.environmentRestriction.isEmpty() || cw.environmentRestriction=="math" );
            if(cw.lines.size()==1 && isPotentialMathCommand && completer->latexParser.possibleCommands["math"].contains(cwCmd)){
                LatexEditorView *view = editor->property("latexEditor").value<LatexEditorView *>();
                Q_ASSERT(view);
                inMath=view->isInMathHighlighting(cursor);
            }

            //for (int i = maxWritten - cursor.columnNumber(); i > 0; i--) cursor.deleteChar();
            if(maxWritten>cursor.columnNumber()){
                cursor.movePosition(maxWritten-cursor.columnNumber(),QDocumentCursor::NextCharacter,QDocumentCursor::KeepAnchor);
                editor->document()->clearLanguageMatches(); // fix #489 (delimiter mismatch marker is not cleared)
                cursor.removeSelectedText();
            }
            //for (int i = cursor.columnNumber() - curStart; i > 0; i--) cursor.deletePreviousChar();
            if(curStart<cursor.columnNumber()){
                cursor.movePosition(cursor.columnNumber()-curStart,QDocumentCursor::PreviousCharacter,QDocumentCursor::KeepAnchor);
                editor->document()->clearLanguageMatches(); // fix #489 (delimiter mismatch marker is not cleared)
                cursor.removeSelectedText();
            }
			if (!autoOverridenText.isEmpty()) {
				cursor.insertText(autoOverridenText);
				cursor.movePosition(autoOverridenText.length(), QDocumentCursor::PreviousCharacter);
				editor->resizeAutoOverridenPlaceholder(cursor, autoOverridenText.size());
				autoOverridenText = "";
			}
			//cursor.endEditBlock(); //doesn't work and lead to crash when auto indentation is enabled => TODO:figure out why
			//  cursor.setColumnNumber(curStart);
			CodeSnippet::PlaceholderMode phMode = (LatexCompleter::config && LatexCompleter::config->usePlaceholders) ? CodeSnippet::PlacehodersActive : CodeSnippet::PlaceholdersRemoved;

            if(cw.lines.size()==1 && isPotentialMathCommand && completer->latexParser.possibleCommands["math"].contains(cwCmd)){
                if(!inMath && LatexCompleter::config && LatexCompleter::config->autoInsertMathDelimiters){
                    // add $$ to mathcommand outsiode math env
                    cw.lines.first().prepend(LatexCompleter::config->startMathDelimiter);
                    cw.lines.first().append(LatexCompleter::config->stopMathDelimiter);
                    // move cursors
                    if(cw.cursorOffset>-1) cw.cursorOffset++;
                    if(cw.anchorOffset>-1) cw.anchorOffset++;
                    for(int i=0;i<cw.placeHolders.size();i++){
                        for(int j=0;j<cw.placeHolders[i].size();j++){
                            cw.placeHolders[i][j].offset++;
                        }
                    }
                }
            }
			cw.insertAt(editor, &cursor, phMode, !completer->startedFromTriggerKey, completer->forcedKeyval);
			editor->document()->endMacro();

			return true;
		}
		return false;
	}

	void removeRightWordPart()
	{
		if (!editor) return;
		QDocumentCursor cursor = editor->cursor();
		for (int i = maxWritten - cursor.columnNumber(); i > 0; i--) cursor.deleteChar();
		maxWritten = cursor.columnNumber();
		editor->setCursor(cursor);//necessary to keep the cursor at the same place (but why???)  TODO: remove this line (it cause \ to disable placeholders which other keys don't disable)
	}

    ///selects an index in the completion suggestion list
	void select(const QModelIndex &ind)
	{
		if (!completer || !completer->list) return;
		completer->list->setCurrentIndex(ind);
		completer->selectionChanged(ind);
	}

    ///moves the selection index to the next/previous delta-th entry in the suggestion list
	bool selectDelta(const int delta)
	{
		if (!completer || !completer->list || !completer->list->isVisible()) {
			resetBinding();
			return false;
		}
		QModelIndex ind = completer->list->model()->index(completer->list->currentIndex().row() + delta, 0, QModelIndex());
		if (!ind.isValid()) {
			if (delta < 0) ind = completer->list->model()->index(0, 0, QModelIndex());
			else if (delta > 0) ind = completer->list->model()->index(completer->list->model()->rowCount() - 1, 0, QModelIndex());
		}
		if (ind.isValid()) select(ind);
		return true;
	}

	/*!
	 * Complete the common part of all remaining possible completions.
	 * \return true if there was a common part, that could be completed.
	 */
	bool completeCommonPrefix(bool reducedRange = false)
	{
		QString my_curWord = getCurWord();
		if (my_curWord.isEmpty()) return false;
		if (!completer) return false;
		// get list of most recent choices
		const QList<CompletionWord> &words = completer->listModel->getWords();
		// filter list for longest common characters
		if (words.count() > 1) {
            QString myResult = words.at(1).word; // skip favorite
            if(!my_curWord.startsWith("\\")){
                myResult = words.at(0).word; // don't skip if no command
            }
			int curWordLength = my_curWord.length();
			my_curWord = completer->listModel->getLastWord().word;

			if (reducedRange && words.count() > 10) {
				my_curWord = words.at(10).word;
			}


            if(showMostUsed==2){
                // as the list is unsorted, all words must be checked !!!
                int j=0;
                bool allIdentical=false;
                for (j = 0; (j < my_curWord.length() && j < myResult.length()); j++) {
                    for(const auto &cw : words){
                        if(cw.word.length()<=j){
                            allIdentical=false;
                            break;
                        }
                        if(cw.word[j]!=myResult[j]){
                            allIdentical=false;
                            break;
                        }
                        allIdentical=true;
                    }
                    if(!allIdentical){
                        break;
                    }
                }
                if(!allIdentical){
                    j=j-1;
                }
                if(j>0){
                    myResult = myResult.left(j);
                }else{
                    return true;
                }
            }else{
                for (int j = curWordLength; (j < my_curWord.length() && j < myResult.length()); j++) {
                    if (myResult[j] != my_curWord[j]) {
                        myResult = myResult.left(j);
                    }
                }
            }

			if (myResult.length() == curWordLength) {
				return false;  // no common segment to complete
			}

			removeRightWordPart();
            if(showMostUsed==2){
                // fuzzy mode
                // remove left hand side as well
                QDocumentCursor cursor = editor->cursor();
                for (int i = curWordLength; i > 0; i--) cursor.deletePreviousChar();
                maxWritten = cursor.columnNumber();
                editor->setCursor(cursor);
                curWordLength=0;
            }
			insertText(myResult.right(myResult.length() - curWordLength));
			completer->filterList(getCurWord(), getMostUsed());
			if (!completer->list->currentIndex().isValid())
				select(completer->list->model()->index(0, 0, QModelIndex()));
			return true;
		} else {
			if (showMostUsed == 1) return false;
			insertCompletedWord();
			resetBinding();
			return true;
		}
	}

	void simpleRestoreAutoOverride(const QString &written = "????") //simple means without protecting the change from undo/redo
	{
		if (!editor) return;
		if (!autoOverridenText.isEmpty() && !editor->isAutoOverrideText(written)) {
			int curpos = editor->cursor().columnNumber();
			if (curpos < maxWritten) {
				QDocumentCursor c = editor->cursor();
				c.movePosition(maxWritten - curpos, QDocumentCursor::NextCharacter);
				editor->setCursor(c);
			}
			editor->insertText(autoOverridenText);
			QDocumentCursor c = editor->cursor();
			c.movePosition(autoOverridenText.length() + (curpos < maxWritten ? maxWritten - curpos : 0), QDocumentCursor::PreviousCharacter);
			editor->setCursor(c);
			editor->resizeAutoOverridenPlaceholder(c, autoOverridenText.size());
		}
	}

	virtual bool keyPressEvent(QKeyEvent *event, QEditor *editor)
	{
		Q_ASSERT (completer && completer->listModel);
		if (!completer || !completer->listModel) return false;
        if (event->key() == Qt::Key_Shift || event->key() == Qt::Key_Alt || event->key() == Qt::Key_AltGr || event->key() == Qt::Key_Control || event->key() == Qt::Key_CapsLock)
			return false;
		if (!active) return false; //we should never have been called
		bool handled = false;
		if (event->key() == Qt::Key_Backspace) {
			maxWritten--;
            QDocumentCursorHandle *dch=editor->cursorHandle();
            Q_ASSERT(dch);
            dch->deletePreviousChar();
            if (dch->columnNumber() <= curStart) {
				resetBinding();
				return true;
            } else if (dch->columnNumber() + 1 <= curStart && !showAlways) {
				completer->widget->hide();
				return true;
			}
			handled = true;
		} else if (event->key() == Qt::Key_Escape) {
			simpleRestoreAutoOverride("");
			resetBinding();
			return true;
		} else if (event->key() == Qt::Key_Delete) {
			if (editor->cursor().columnNumber() < maxWritten) maxWritten--;
			if (completer->forcedRef) {
				if (editor->cursor().nextChar() == '}')
					completer->forcedRef = false;
			}
			editor->cursor().deleteChar();
			handled = true;
		} else if (event->key() == Qt::Key_Left) {
			if (event->modifiers()) {
				resetBinding();
				return false;
			}
			editor->setCursorPosition(curLineNumber, editor->cursor().columnNumber() - 1);
			if (editor->cursor().columnNumber() <= curStart) resetBinding();
			handled = true;
		} else if (event->key() == Qt::Key_Right) {
			if (event->modifiers()) {
				resetBinding();
				return false;
			}
			editor->setCursorPosition(curLineNumber, editor->cursor().columnNumber() + 1);
			if (editor->cursor().columnNumber() > maxWritten) resetBinding();
			handled = true;
		} else if (event->key() == Qt::Key_Up) return selectDelta(-1);
		else if (event->key() == Qt::Key_Down) return selectDelta(+1);
		else if (event->key() == Qt::Key_PageUp) return  selectDelta(-5);
		else if (event->key() == Qt::Key_PageDown) return  selectDelta(+5);
		else if (event->key() == Qt::Key_Home) {
			if (!completer->list->isVisible()) {
				resetBinding();
				return false;
			}
			QModelIndex ind = completer->list->model()->index(0, 0, QModelIndex());
			if (ind.isValid()) select(ind);
			return true;
		} else if (event->key() == Qt::Key_End) {
			if (!completer->list->isVisible()) {
				resetBinding();
				return false;
			}
			QModelIndex ind = completer->list->model()->index(completer->list->model()->rowCount() - 1, 0, QModelIndex());
			if (ind.isValid()) select(ind);
			return true;
		}  else if (event->key() == Qt::Key_Tab) {
			if (completeCommonPrefix(true)) {
				return true;
			} else if (insertCompletedWord()) {
				resetBinding();
				return true;
			}
			return false;
		}  else if (event->key() == Qt::Key_Space && event->modifiers() == Qt::ShiftModifier) {
			//showMostUsed=!showMostUsed;
			//handled=true;
			showMostUsed++;
            if (showMostUsed > 3)
				showMostUsed = 0;
			completer->tbAbove->setCurrentIndex(showMostUsed);
			completer->tbBelow->setCurrentIndex(showMostUsed);
			return true;
		} else if (event->key() == Qt::Key_Return || event->key() == Qt::Key_Enter) {
            insertCompletedWord();
			resetBinding();
			return true;
        } else {
            if (event->text().length() != 1 || (event->text() == " " && !completer->listModel->isNextCharPossible(' ') ) ) {
				resetBinding();
				return false;
			}

			QChar written = event->text().at(0);
			if (written == '\\') {
				if (getCurWord() == "\\") {
					resetBinding();
					return false;
				} else if (getCurWord() == "") {
					maxWritten = curStart + 1;
				} else {
                    if (LatexCompleter::config && LatexCompleter::config->eowCompletes && !completer->isCurrentWordUserConstruct()) {
						insertCompletedWord();
					}
					QDocumentCursor edc = editor->cursor();
					if (edc.hasSelection()) {
						edc.removeSelectedText();
						editor->setCursor(edc);
					}
					curStart = edc.columnNumber();
					maxWritten = curStart + 1;
				}
				bool autoOverride = editor->isAutoOverrideText("\\");
				if (!autoOverride) editor->cursor().insertText(written);
				else {
					QDocumentCursor c = editor->cursor();
					editor->document()->beginMacro();
					c.deleteChar();
					c.insertText("\\");
					editor->document()->endMacro();
					autoOverridenText = "\\";
				}
				//editor->insertText(written); <- can't use that since it may break the completer by auto closing brackets
				handled = true;
			} else if (completer->acceptChar(written, editor->cursor().columnNumber() - curStart)) {
				insertText(written);
				handled = true;
			} else if (event->text().length() == 1 && getCommonEOW().contains(event->text().at(0)) ) {
				QString curWord = getCurWord();

				if (curWord == "\\" || !LatexCompleter::config || !LatexCompleter::config->eowCompletes) {
					resetBinding();
					simpleRestoreAutoOverride(written);
					return false;
				}
				const QList<CompletionWord> &words = completer->listModel->getWords();
				QString newWord;
				int eowchars = 10000;
				foreach (const CodeSnippet &w, words) {
					if (!w.word.startsWith(curWord)) continue;
					if (w.word.length() == curWord.length()) {
						newWord = w.word;
						break;
					}
					int newoffset = w.lines.first().indexOf(written, curWord.length());
					if (newoffset < 0) continue;
					int neweowchars = 0;
					for (int i = curWord.length(); i < newoffset; i++)
						if (getCommonEOW().contains(w.lines.first()[i]))
							neweowchars++;
					if (neweowchars < eowchars) {
						newWord = w.word;
						eowchars = neweowchars;
						if (eowchars == 1) break;
					}
				}

				if (!newWord.isEmpty() && newWord.length() != curWord.length()) {
					QString insertion = newWord.mid(curWord.length(), newWord.indexOf(written, curWord.length()) - curWord.length() + 1); //choose text until written eow character
					insertText(insertion);
					//insertText(written);
					handled = true;
				}

				if (!handled) {
					insertCompletedWord();
					if (newWord.isEmpty())
						simpleRestoreAutoOverride(written);
					//insertText(written);
					resetBinding();
					return false;//oldBinding->keyPressEvent(event,editor); //call old input binding for long words (=> key replacements after completions, but the user can still write \")
				}
			} else {
				int curLength = getCurWord().length();
				resetBinding();
				return curLength >= 2 &&  oldBinding->keyPressEvent(event, editor); //call old input binding for long words (=> key replacements after completions, but the user can still write \")
			}
		}
		completer->filterList(getCurWord(), showMostUsed);
		if (!completer->list->currentIndex().isValid())
			select(completer->list->model()->index(0, 0, QModelIndex()));
		return handled;
	}

    virtual bool inputMethodEvent(QInputMethodEvent* event, QEditor *editor)
    {
        Q_ASSERT (completer && completer->listModel);
        if (!completer || !completer->listModel) return false;
        if(event->commitString().isEmpty()){
                return false;
        }

        bool handled=false;
        QString text=event->commitString();
        if (text.length() != 1 || text == " ") {
            resetBinding();
            return false;
        }

        QChar written = text.at(0);
        if (written == '\\') {
            if (getCurWord() == "\\") {
                resetBinding();
                return false;
            } else if (getCurWord() == "") {
                maxWritten = curStart + 1;
            } else {
                if (LatexCompleter::config && LatexCompleter::config->eowCompletes) {
                    insertCompletedWord();
                }
                QDocumentCursor edc = editor->cursor();
                if (edc.hasSelection()) {
                    edc.removeSelectedText();
                    editor->setCursor(edc);
                }
                curStart = edc.columnNumber();
                maxWritten = curStart + 1;
            }
            bool autoOverride = editor->isAutoOverrideText("\\");
            if (!autoOverride) editor->cursor().insertText(written);
            else {
                QDocumentCursor c = editor->cursor();
                editor->document()->beginMacro();
                c.deleteChar();
                c.insertText("\\");
                editor->document()->endMacro();
                autoOverridenText = "\\";
            }
            //editor->insertText(written); <- can't use that since it may break the completer by auto closing brackets
            handled = true;
        } else if (completer->acceptChar(written, editor->cursor().columnNumber() - curStart)) {
            insertText(written);
            handled = true;
        } else if (getCommonEOW().contains(written) ) {
            QString curWord = getCurWord();

            if (curWord == "\\" || !LatexCompleter::config || !LatexCompleter::config->eowCompletes) {
                resetBinding();
                simpleRestoreAutoOverride(written);
                return false;
            }
            const QList<CompletionWord> &words = completer->listModel->getWords();
            QString newWord;
            int eowchars = 10000;
            foreach (const CodeSnippet &w, words) {
                if (!w.word.startsWith(curWord)) continue;
                if (w.word.length() == curWord.length()) {
                    newWord = w.word;
                    break;
                }
                int newoffset = w.lines.first().indexOf(written, curWord.length());
                if (newoffset < 0) continue;
                int neweowchars = 0;
                for (int i = curWord.length(); i < newoffset; i++)
                    if (getCommonEOW().contains(w.lines.first()[i]))
                        neweowchars++;
                if (neweowchars < eowchars) {
                    newWord = w.word;
                    eowchars = neweowchars;
                    if (eowchars == 1) break;
                }
            }

            if (!newWord.isEmpty() && newWord.length() != curWord.length()) {
                QString insertion = newWord.mid(curWord.length(), newWord.indexOf(written, curWord.length()) - curWord.length() + 1); //choose text until written eow character
                insertText(insertion);
                //insertText(written);
                handled = true;
            }

            if (!handled) {
                insertCompletedWord();
                if (newWord.isEmpty())
                    simpleRestoreAutoOverride(written);
                //insertText(written);
                resetBinding();
                return false;//oldBinding->keyPressEvent(event,editor); //call old input binding for long words (=> key replacements after completions, but the user can still write \")
            }
        }

        completer->filterList(getCurWord(), showMostUsed);
        if (!completer->list->currentIndex().isValid())
            select(completer->list->model()->index(0, 0, QModelIndex()));
        return handled;
    }

	void cursorPositionChanged(QEditor *edit)
	{
		if (edit != editor) return; //should never happen
		QDocumentCursor c = editor->cursor();
		if (c.lineNumber() != curLineNumber || c.columnNumber() < curStart) resetBinding();
	}

	void setMostUsed(int mu, bool quiet = false)
	{
		showMostUsed = mu;
		if (quiet)
			return;
		completer->filterList(getCurWord(), showMostUsed);
		if (!completer->list->currentIndex().isValid())
			select(completer->list->model()->index(0, 0, QModelIndex()));
	}

	int getMostUsed()
	{
		return showMostUsed;
	}

	void resetBinding()
	{
        if (completer){
			completer->listModel->setEnvironMode(false);
            completer->setFilter(QString());
        }
		showMostUsed = false;
		QString curWord = getCurWord();
		if (!active) return;
		QToolTip::hideText();
		//reenable auto close chars
        if(completer)
            editor->setFlag(QEditor::AutoCloseChars, completer->editorAutoCloseChars);
		editor->setInputBinding(oldBinding);
        if (completer && completer->widget && completer->widget->isVisible()){
            completer->widget->hide();
			editor->setFocus();
        }
		if (completer) {
			completer->disconnect(editor, SIGNAL(cursorPositionChanged()), completer, SLOT(cursorPositionChanged()));
		}
		active = false;
		//editor=0; this leads to a crash, as the editor is still in use after reseting the cursor
		if (completer && completer->completingKey() && curWord.endsWith("=")) {
			LatexEditorView *view = editor->property("latexEditor").value<LatexEditorView *>();
			Q_ASSERT(view);
			view->mayNeedToOpenCompleter();
		}
        if (completer && completer->completingGraphic() && curWord.endsWith("/")) {
			completer->complete(editor, LatexCompleter::CompletionFlags(LatexCompleter::CF_FORCE_VISIBLE_LIST | LatexCompleter::CF_FORCE_GRAPHIC));
		}
	}

	void bindTo(QEditor *edit, LatexCompleter *caller, bool forced, int start)
	{
		if (active) resetBinding();
		active = true;
		completer = caller;
		editor = edit;
        oldBinding = (editor->inputBindings().count() > 0 ? editor->inputBindings()[0] : nullptr);
		editor->setInputBinding(this);
		curStart = start > 0 ? start : 0;
		maxWritten = editor->cursor().columnNumber();
		if (maxWritten < start) maxWritten = start;
		curLineNumber = editor->cursor().lineNumber();
		showAlways = forced; //curWord!="\\";
		completer->filterList(getCurWord());
		if (showAlways) {
			completer->widget->show();
            completer->widget->raise(); // fix #3598 - problem with qdocks
			select(completer->list->model()->index(0, 0, QModelIndex()));
		}
	}

	bool isActive()
	{
		return active;
	}

	QString autoOverridenText;
private:
	bool active;
	bool showAlways;
	int showMostUsed;
	LatexCompleter *completer;
	QEditor *editor;
	QEditorInputBindingInterface *oldBinding;
	QString completionWord;
	int curStart, maxWritten;
	int curLineNumber;
};

//Q_DECLARE_METATYPE(LatexEditorView *)

CompleterInputBinding *completerInputBinding = new CompleterInputBinding();
//------------------------------Item Delegate--------------------------------
class CompletionItemDelegate: public QItemDelegate
{
public:
    explicit CompletionItemDelegate(QObject *parent = nullptr): QItemDelegate(parent)
	{
	}

	void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const
	{
		QVariant v = index.model()->data(index);
		if (!v.isValid() || !v.canConvert<CompletionWord>()) return;
		CompletionWord cw = v.value<CompletionWord>();
		if (cw.lines.empty() || cw.placeHolders.empty()) return;
		QFont fNormal = option.font;
		QFont fPlHolder = option.font;
		//fPlHolder.setItalic(true);
		QColor normalColor, plHolderColor;
		if ((QStyle::State_HasFocus | QStyle::State_Selected) & option.state) {
			painter->fillRect(option.rect, option.palette.brush(QPalette::Highlight));
			normalColor = option.palette.color(QPalette::HighlightedText);
		} else {
			painter->fillRect(option.rect, option.palette.brush(QPalette::Base)); //doesn't seem to be necessary
			normalColor = option.palette.color(QPalette::Text);
		}
		painter->setPen(normalColor);
		plHolderColor = normalColor;
		plHolderColor.setAlpha(128);

        QRectF r = option.rect;
		r.setLeft(r.left() + 2);
		bool drawPlaceholder = !cw.placeHolders.empty();
		QString firstLine = cw.lines[0];
		if (!cw.getName().isEmpty()) {
			drawPlaceholder = false;
			firstLine = cw.getName();
		}
		if (!drawPlaceholder)
            painter->drawText(r, Qt::AlignLeft | Qt::AlignTop | Qt::TextSingleLine, firstLine);
		else {
            QFontMetricsF fmn(fNormal);
            QFontMetricsF fmi(fPlHolder);
			int p = 0;
			for (int i = 0; i < cw.placeHolders[0].size(); i++) {
				QString temp = firstLine.mid(p, cw.placeHolders[0][i].offset - p);
                painter->drawText(r, Qt::AlignLeft | Qt::AlignTop | Qt::TextSingleLine, temp);
				r.setLeft(r.left() + UtilsUi::getFmWidth(fmn, temp));
				temp = firstLine.mid(cw.placeHolders[0][i].offset, cw.placeHolders[0][i].length);
				painter->setFont(fPlHolder);
				painter->setPen(plHolderColor);
                painter->drawText(r, Qt::AlignLeft | Qt::AlignTop | Qt::TextSingleLine, temp);
				r.setLeft(r.left() + UtilsUi::getFmWidth(fmi, temp) + 1);
				p = cw.placeHolders[0][i].offset + cw.placeHolders[0][i].length;
				painter->setFont(fNormal);
				painter->setPen(normalColor);
				if (p > firstLine.length()) break;
			}
            painter->drawText(r, Qt::AlignLeft | Qt::AlignTop | Qt::TextSingleLine, firstLine.mid(p));
		}
	}
};



//----------------------------list model------------------------------------
LatexCompleterConfig *CompletionListModel::config = nullptr;
int CompletionListModel::rowCount(const QModelIndex &parent) const
{
	Q_UNUSED(parent)
	return words.count();
}

QVariant CompletionListModel::data(const QModelIndex &index, int role)const
{
	if (!index.isValid())
		return QVariant();

	if (index.row() >= words.count())
		return QVariant();

	if (role == Qt::DisplayRole) {
		QVariant temp;
		temp.setValue(words.at(index.row()));
		return temp;
	} else
		return QVariant();
}

QVariant CompletionListModel::headerData(int section, Qt::Orientation orientation,
        int role) const
{
	Q_UNUSED(role)
	Q_UNUSED(orientation)
	Q_UNUSED(section)

	return QVariant();
}

bool CompletionListModel::isNextCharPossible(const QChar &c)
{
	//if (words.count()>100) //probable that every char is there (especially since acceptedChars is already checked)
	//	return true;  -> leads to faulty behaviour (\b{ is supposed to be within list ...)
	Qt::CaseSensitivity cs = Qt::CaseInsensitive;
	if (LatexCompleter::config &&
	        LatexCompleter::config->caseSensitive == LatexCompleterConfig::CCS_CASE_SENSITIVE)
		cs = Qt::CaseSensitive;
	QString extension = curWord + c;
    foreach (const CompletionWord &cw, words){
        // disregard spaces at the end of the word for assuming a word was entered completely (#3544)
        if (cw.word.trimmed().startsWith(extension, cs)) return true;
    }
	return false;
}

bool CompletionListModel::canFetchMore(const QModelIndex &) const
{
	return mCanFetchMore;
}

void CompletionListModel::fetchMore(const QModelIndex &)
{
	beginInsertRows(QModelIndex(), words.count(), qMin(words.count() + 100, mWordCount));
	filterList(mLastWord, mLastMU, true, mLastType);
	endInsertRows();
}

CompletionWord CompletionListModel::getLastWord()
{
	return mLastWordInList;
}

void CompletionListModel::setKeyValWords(const QString &name, const QSet<QString> &newwords)
{
    if(keyValLists.contains(name) && keyValLists[name].count()==newwords.count()){
        // don't recreate existing keyval list
        return;
    }
	QList<CompletionWord> newWordList;
	newWordList.clear();
	for (QSet<QString>::const_iterator i = newwords.constBegin(); i != newwords.constEnd(); ++i) {
		QString str = *i;
		QString validValues;
		if (str.contains("#") && !str.startsWith("#")) {
			int j = str.indexOf("#");
			validValues = str.mid(j + 1);
            str = str.left(j);
			QStringList lst = validValues.split(",");
			QString key = str;
			if (key.endsWith("="))
				key.chop(1);
            setKeyValWords(name + "/" + key, convertStringListtoSet(lst));
            if(validValues=="#L"){
                str+="%<dimension%>"; // add dimension placeholder
            }
		}
		CompletionWord cw(str, false);
		cw.index = 0;
		cw.usageCount = -2;
		cw.snippetLength = 0;
		newWordList.append(cw);
	}
    std::sort(newWordList.begin(), newWordList.end());

    keyValLists.insert(name, newWordList);
}
/*!
 * \brief set environment filer
 * Only completion words are shown which contain the filter string in environmentRestriction property or which have no restriction (empty string in that property)
 * \param filter
 */
void CompletionListModel::setEnvironmentFilter(const QString &filter)
{
    m_filter=filter;
}

void CompletionListModel::setDisableMostUsedSorting(bool set)
{
    m_disable_mostUsed_sorting=set;
}

void CompletionListModel::setContextWords(const QSet<QString> &newwords, const QString &context)
{
	QList<CompletionWord> newWordList;
	newWordList.clear();
	for (QSet<QString>::const_iterator i = newwords.constBegin(); i != newwords.constEnd(); ++i) {
		QString str = *i;
		QString validValues;
		if (str.contains("#")) {
			int j = str.indexOf("#");
			validValues = str.mid(j + 1);
			str = str.left(j);
			QStringList lst = validValues.split(",");
			QString key = str;
			if (key.endsWith("="))
				key.chop(1);
            setKeyValWords(context + "/" + key, convertStringListtoSet(lst));
		}
		CompletionWord cw(str);
		cw.index = 0;
        cw.usageCount = 2;

		cw.snippetLength = 0;
		newWordList.append(cw);
	}
    std::sort(newWordList.begin(), newWordList.end());

	contextLists.insert(context, newWordList);
}

QString makeSortWord(const QString &normal)
{
    QString res = normal;
	res.replace("{", "!"); //js: still using dirty hack, however order should be ' '{[* abcde...
	res.replace("}", "!"); // needs to be replaced as well for sorting \bgein{abc*} after \bgein{abc}
	res.replace("[", "\\"); //(first is a space->) !"# follow directly in the ascii table
	res.replace("*", "#");
	return res;
}

void CompletionListModel::setEnvironMode(bool mode)
{
	mEnvMode = mode;
}
/*!
 * \brief special less operator for comapring fuzzy based on scores
 * \param s1
 * \param s2
 * \return
 */
bool cwLessThan(const CompletionWord &s1, const CompletionWord &s2)
{
    return s1.score > s2.score;
}
/*!
 * \brief replace key in completion word with replacement
 * \param cw base completion word which is copied
 * \param key
 * \param replacement
 * \param makePlaceholder make replaced word as a new placeholder
 * \return copied and manipulated completion word
 */
CompletionWord manipulateCompletionWord(CompletionWord cw,QString key,QString replacement,bool makePlaceholder=false){
    int index = cw.lines[0].indexOf(key);
    cw.word.replace(key, replacement);
    cw.sortWord.replace(key, replacement);
    cw.lines[0].replace(key, replacement);
    for (int i = 0; i < cw.placeHolders.count(); i++) {
        if (cw.placeHolders[i].isEmpty())
            continue;
        for (int j = 0; j < cw.placeHolders[i].count(); j++) {
            CodeSnippetPlaceHolder &ph = cw.placeHolders[i][j];
            if (ph.offset > index)
                ph.offset += replacement.length() - key.length();
        }
    }
    if(makePlaceholder){
        CodeSnippetPlaceHolder ph;
        ph.offset=index;
        ph.length=replacement.length();
        ph.id=-1;
        ph.flags=CodeSnippetPlaceHolder::AutoSelect;
        int k=0;
        for(;k<cw.placeHolders.last().length();++k){
            if(cw.placeHolders.last().value(k).offset>index)
                break;
        }
        cw.placeHolders.last().insert(k,ph);
    }
    return cw;
}

void CompletionListModel::filterList(const QString &word, int mostUsed, bool fetchMore, CodeSnippet::Type type)
{
    if (mostUsed < 0)
		mostUsed = LatexCompleter::config->preferedCompletionTab;
	if (!word.isEmpty() && word == curWord && mostUsed == mostUsedUpdated && !fetchMore) return; //don't return if mostUsed differnt from last call
	mLastWord = word;
	mLastMU = mostUsed;
	mLastType = type;
	mCanFetchMore = false;
	mostUsedUpdated = mostUsed;
	if (!fetchMore)
		words.clear();
	Qt::CaseSensitivity cs = Qt::CaseInsensitive;
	bool checkFirstChar = false;
	if (LatexCompleter::config) {
		if (LatexCompleter::config->caseSensitive == LatexCompleterConfig::CCS_CASE_SENSITIVE)
			cs = Qt::CaseSensitive;
		checkFirstChar = LatexCompleter::config->caseSensitive == LatexCompleterConfig::CCS_FIRST_CHARACTER_CASE_SENSITIVE && word.length() > 1;
	}
	int cnt = 0;
	QString sortWord = makeSortWord(word);
    if(mostUsed==2){
        //fuzzy search
        // proof of concept
        // generate regexp
        //QTime tm;
        //tm.start();
#if (QT_VERSION>=QT_VERSION_CHECK(5,14,0))
        QStringList chars=word.split("",Qt::SkipEmptyParts);
#else
        QStringList chars=word.split("",QString::SkipEmptyParts);
#endif
        if(chars.value(0)==QChar('\\')){
            chars.takeFirst();
        }
        QString regExpression=chars.join(".*");

        QRegularExpression rx(regExpression);

        words=QtConcurrent::blockingFiltered(baselist,[rx,this](const CompletionWord &item){
            return item.sortWord.contains(rx) && (item.environmentRestriction.isEmpty() || item.environmentRestriction==m_filter);
        });

        QtConcurrent::blockingMap(words,[word](CompletionWord &item){
            int score=0;
            int l=0;
            int lastMatch=-2;
            for(int i=0;i<item.sortWord.length();i++){
                if(l>=word.length())
                    break;
                if(item.sortWord.at(i)==word.at(l)){
                    if(lastMatch+1==i)
                        score+=20;
                    score-=i; // later position are degraded
                    lastMatch=i;
                    l++;
                }
            }
            if (item.word.contains('@')) {
                if(item.word.contains("@@")){ // special treatment for command-names containing @
                    QString ln = item.lines[0];
                    ln.replace("@@", "@");
                    item=CompletionWord(ln);
                }else{
                    QString ln = item.lines[0];
                    ln.replace("{@}", "{%<bibid%>}");
                    ln.replace("{@l}", "{%<label%>}");
                    item=CompletionWord(ln);
                }
            }
            // reduce score for atypical or unused
            if(item.index){
                // don't upvote reference commands
                score+=item.usageCount<=0 ? 10*item.usageCount : 10;
            }
            item.score=score;
        });

        std::stable_sort(words.begin(),words.end(),cwLessThan);
        //qDebug()<<tm.elapsed();
    }else{
        // normal sorting
        if (!fetchMore) {
            it = std::lower_bound(baselist.begin(), baselist.end(), CompletionWord(word));
        }
        // special treatment for citation commands as they generated on the fly
        if (it == baselist.end() || !it->word.startsWith(word, cs)) {
            int i = word.lastIndexOf("{");
            QString test = word.left(i) + "{";
            QList<CompletionWord>::iterator lIt = std::lower_bound(baselist.begin(), baselist.end(), CompletionWord(test));
            // part of command without argument is in baselist
            // is it a on-the-fly filled command ?
            // try on all possible commands which begin with the word (test), see #2187
            while(lIt!=baselist.end() && lIt->word.startsWith(test)){
                if(lIt->word.contains('@')){
                    QString citeStart = word.mid(i + 1);
                    QString ln = lIt->lines[0];
                    struct Rpl {
                        QString id;
                        QList<CompletionWord>& lst;
                    };

                    QMap<QString,std::shared_ptr<Rpl>>replacement;
                    std::shared_ptr<Rpl> r0(new Rpl{"{%<bibid%>}",wordsCitations});
                    replacement.insert("@",r0);
                    std::shared_ptr<Rpl> r1(new Rpl{"{%<label%>}",wordsLabels});
                    replacement.insert("@l",r1);
                    for(QMap<QString,std::shared_ptr<Rpl>>::const_iterator localIt=replacement.cbegin();localIt!=replacement.cend();++localIt){
                        QString searchWord="{"+localIt.key()+"}";
                        QString key=localIt.key();
                        std::shared_ptr<Rpl> repl=*localIt;
                        if(ln.contains(searchWord)){
                            if(repl->id.startsWith("{%<"+citeStart)){
                                // keep general id if it matches input
                                CompletionWord cw = manipulateCompletionWord(*lIt,key,repl->id,true);
                                words.append(cw);
                            }
                            cnt++;
                            foreach (const CompletionWord id, repl->lst) {
                                if(!id.word.startsWith(citeStart))
                                    continue;
                                CompletionWord cw = *lIt;
                                int index = cw.lines[0].indexOf(key);
                                cw.word.replace(key, id.word);
                                cw.sortWord.replace(key, id.word);
                                cw.lines[0].replace(key, id.word);
                                for (int i = 0; i < cw.placeHolders.count(); i++) {
                                    if (cw.placeHolders[i].isEmpty())
                                        continue;
                                    for (int j = 0; j < cw.placeHolders[i].count(); j++) {
                                        CodeSnippetPlaceHolder &ph = cw.placeHolders[i][j];
                                        if (ph.offset > index)
                                            ph.offset += id.word.length() - key.length();
                                    }
                                }
                                words.append(cw);
                            }
                            cnt += repl->lst.length();
                        }
                    }
                }
                ++lIt;
            }
        }
        //
        CompletionWord mostUsedCW;
        int mostUsedPosition=-1;
        while (it != baselist.end()) {
            if (it->word.startsWith(word, cs) &&
                    (!checkFirstChar || it->word[1] == word[1]) ) {

                // leave out words which are restricted to a certain environment (except for all-mode)
                if (mostUsed < 2 && !it->environmentRestriction.isEmpty() && it->environmentRestriction != m_filter) {
                    ++it;
                    continue;
                }
                if (mostUsed == 3 || it->usageCount >= mostUsed || it->usageCount == -2) {
                    if (mostUsed < 2 && type != CodeSnippet::none && it->type != type) {
                        ++it;
                        continue; // leave out words which don't have the proper type (except for all-mode)
                    }
                    if (mEnvMode) {
                        CompletionWord cw = *it;
                        if (cw.word.startsWith("\\begin") || cw.word.startsWith("\\end")) {
                            QString text = cw.word;
                            int i = text.indexOf('}');
                            text.truncate(i + 1);
                            cw.word = text;
                            cw.sortWord = text;
                            cw.lines = QStringList(text);
                            cw.placeHolders.clear();
                            cw.placeHolders.append(QList<CodeSnippetPlaceHolder>());
                        }

                        if (!words.contains(cw))
                            words.append(cw);
                    } else {
                        // cite command
                        if (it->word.contains('@')) {
                            if(it->word.contains("@@")){ // special treatment for command-names containing @
                                QString ln = it->lines[0];
                                ln.replace("@@", "@");
                                words.append(CompletionWord(ln));
                            }else{
                                QString ln = it->lines[0];
                                struct Rpl {
                                    QString id;
                                    QList<CompletionWord>& lst;
                                };

                                QMap<QString,std::shared_ptr<Rpl>>replacement;
                                std::shared_ptr<Rpl> r0(new Rpl{"bibid",wordsCitations});
                                replacement.insert("@",r0);
                                std::shared_ptr<Rpl> r1(new Rpl{"label",wordsLabels});
                                replacement.insert("@l",r1);
                                for(QMap<QString,std::shared_ptr<Rpl>>::const_iterator localIt=replacement.cbegin();localIt!=replacement.cend();++localIt){
                                    QString searchWord="{"+localIt.key()+"}";
                                    QString key=localIt.key();
                                    std::shared_ptr<Rpl> repl=*localIt;
                                    if(ln.contains(searchWord)){
                                        CompletionWord cw = manipulateCompletionWord(*it,key,repl->id,true);
                                        words.append(cw);
                                        ++cnt;
                                        foreach (const CompletionWord id, repl->lst) {
                                            CompletionWord cw = manipulateCompletionWord(*it,key,id.word,false);
                                            words.append(cw);
                                        }
                                        cnt += repl->lst.length();
                                    }
                                }
                            }
                        } else {
                            if(!m_disable_mostUsed_sorting){
                                if(mostUsedPosition>=0){
                                    if(it->usageCount>mostUsedCW.usageCount){
                                        mostUsedCW=*it;
                                        mostUsedPosition=words.size(); // point to last valid element, will be filled below
                                    }
                                }else{
                                    if(it->usageCount>0){ // don't bother with never used cw
                                        mostUsedCW=*it;
                                        mostUsedPosition=words.size();
                                    }
                                }
                            }
                            words.append(*it);
                        }
                    }
                    cnt++;
                }
            } else {
                if (!it->sortWord.startsWith(sortWord))
                    break; // sorted list
            }
            ++it;
            if (cnt > 100) {
                mCanFetchMore = true;
                break;
            }
        }
        // switch most used to top position (favorite)
        if(mostUsedPosition>=0){
            words.takeAt(mostUsedPosition); // possible expensive
            words.prepend(mostUsedCW);
        }
    }

    curWord = word;
    if (!fetchMore) {
        mWordCount = words.count();
        if (!words.isEmpty())
            mLastWordInList = words.last();
    }
    if (mCanFetchMore && !fetchMore) {
        // calculate real number of rows
        QString wordp = word;
        if (wordp.isEmpty()) {
            mWordCount = baselist.count();
            mLastWordInList = baselist.last();
        } else {
            QChar lst = wordp[wordp.length() - 1];
            ushort nr = lst.unicode();
            wordp[wordp.length() - 1] = QChar(nr + 1);
            QList<CompletionWord>::const_iterator it2 = std::lower_bound(baselist.constBegin(),baselist.constEnd(), CompletionWord(wordp));
            mWordCount = it2 - it;
            if(it2==baselist.constBegin()){
                mLastWordInList = baselist.last();
            }else{
                mLastWordInList = *(--it2);
            }
        }
    }

	if (!fetchMore) {
		beginResetModel();
		endResetModel();
	}
}

void CompletionListModel::incUsage(const QModelIndex &index)
{
	if (!index.isValid())
		return ;

	if (index.row() >= words.size())
		return ;

	int j = index.row();
	CompletionWord curWord = words.at(j);
	if (curWord.usageCount < -1)
		return; // don't count text words

    CodeSnippetList::iterator it = std::lower_bound(wordsCommands.begin(), wordsCommands.end(), curWord);
	if (it == wordsCommands.end()) // not found, e.g. citations
		return;
	if (it->word == curWord.word) {
		it->usageCount++;
		if (curWord.snippetLength > 0) {
			bool replaced = false;
			QList<QPair<int, int> >res = config->usage.values(curWord.index);
			for (int j = 0; j < res.size(); ++j) {
				if (res.at(j).first == curWord.snippetLength) {
					config->usage.remove(curWord.index, res.at(j));
                    config->usage.insert(curWord.index, qMakePair(curWord.snippetLength, it->usageCount));
					replaced = true;
					break;
				}
			}
			if (!replaced)
				config->usage.insert(curWord.index, qMakePair(curWord.snippetLength, it->usageCount)); // new word
		}
	}
}

typedef QPair<int, int> PairIntInt;
void CompletionListModel::setBaseWords(const QSet<QString> &newwords, CompletionType completionType)
{
	QList<CompletionWord> newWordList;
	newWordList.clear();
	for (QSet<QString>::const_iterator i = newwords.constBegin(); i != newwords.constEnd(); ++i) {
		QString str = *i;
		CompletionWord cw(str);
		if (completionType == CT_COMMANDS) {
			cw.index = qHash(str);
			cw.snippetLength = str.length();
			cw.usageCount = 0;
			QList<QPair<int, int> >res = config->usage.values(cw.index);
			foreach (const PairIntInt &elem, res) {
				if (elem.first == cw.snippetLength) {
					cw.usageCount = elem.second;
					break;
				}
			}
		} else {
			cw.index = 0;
			cw.usageCount = -2;
			cw.snippetLength = 0;
		}
		newWordList.append(cw);
	}
    std::sort(newWordList.begin(), newWordList.end());

	switch (completionType) {
	case CT_NORMALTEXT:
		wordsText = newWordList;
		break;
	case CT_CITATIONS:
		wordsCitations = newWordList;
		break;
	default:
		wordsCommands = newWordList;
	}

	//if (completionType==CT_NORMALTEXT) wordsText=newWordList;
	//else wordsCommands=newWordList;
	baselist = wordsCommands;
}

void CompletionListModel::setBaseWords(const std::set<QString> &newwords, CompletionType completionType)
{
    QList<CompletionWord> newWordList;
    newWordList.clear();
    for (std::set<QString>::const_iterator i = newwords.cbegin(); i != newwords.cend(); ++i) {
        QString str = *i;
        CompletionWord cw(str);
        if (completionType == CT_COMMANDS) {
            cw.index = qHash(str);
            cw.snippetLength = str.length();
            cw.usageCount = 0;
            QList<QPair<int, int> >res = config->usage.values(cw.index);
            foreach (const PairIntInt &elem, res) {
                if (elem.first == cw.snippetLength) {
                    cw.usageCount = elem.second;
                    break;
                }
            }
        } else {
            cw.index = 0;
            cw.usageCount = -2;
            cw.snippetLength = 0;
        }
        newWordList.append(cw);
    }

    switch (completionType) {
    case CT_NORMALTEXT:
        wordsText = newWordList;
        break;
    case CT_CITATIONS:
        wordsCitations = newWordList;
        break;
    default:
        wordsCommands = newWordList;
    }

    //if (completionType==CT_NORMALTEXT) wordsText=newWordList;
    //else wordsCommands=newWordList;
    baselist = wordsCommands;
}

void CompletionListModel::setBaseWords(const QList<CompletionWord> &newwords, CompletionType completionType)
{
	QList<CompletionWord> newWordList;
	newWordList.clear();
	foreach (const CompletionWord &cw, newwords) {
		newWordList.append(cw);
	}
    std::sort(newWordList.begin(), newWordList.end());

	//if (completionType==CT_NORMALTEXT) wordsText=newWordList;
	//else wordsCommands=newWordList;
	switch (completionType) {
	case CT_NORMALTEXT:
		wordsText = newWordList;
		break;
	case CT_CITATIONS:
		wordsCitations = newWordList;
		break;
	default:
		wordsCommands = newWordList;
	}

	baselist = wordsCommands;
}

void CompletionListModel::setBaseWords(const CodeSnippetList &baseCommands, const CodeSnippetList &newwords, CompletionType completionType)
{
	CodeSnippetList newWordList;

	newWordList << baseCommands;
	newWordList.unite(newwords);

	CodeSnippetList::iterator last = std::unique(newWordList.begin(), newWordList.end());
	newWordList.erase(last, newWordList.end());

	switch (completionType) {
	case CT_NORMALTEXT:
		wordsText = newWordList;
		break;
	case CT_CITATIONS:
		wordsCitations = newWordList;
		break;
	case CT_LABELS:
		wordsLabels = newWordList;
		break;
	default:
		wordsCommands = newWordList;
	}

	baselist = newWordList;
}

void CompletionListModel::setAbbrevWords(const QList<CompletionWord> &newwords)
{
	wordsAbbrev = newwords;
    std::sort(wordsAbbrev.begin(), wordsAbbrev.end());
}

void CompletionListModel::setConfig(LatexCompleterConfig *newConfig)
{
	config = newConfig;
}


//------------------------------completer-----------------------------------
LatexReference *LatexCompleter::latexReference = nullptr;
LatexCompleterConfig *LatexCompleter::config = nullptr;

LatexCompleter::LatexCompleter(const LatexParser &latexParser, QObject *p): QObject(p), latexParser(latexParser), maxWordLen(0), editorAutoCloseChars(false), forcedRef(false),
    forcedGraphic(false), forcedCite(false), forcedPackage(false), forcedKeyval(false), forcedSpecialOption(false), forcedLength(false), startedFromTriggerKey(false),disable_mu_sorting(false)
{
	//   addTrigger("\\");
	if (!qobject_cast<QWidget *>(parent()))
        QMessageBox::critical(nullptr, "Serious PROBLEM", QString("The completer has been created without a parent widget. This is impossible!\n") +
		                      QString("Please report it ASAP to the bug tracker on texstudio.sf.net and check if your computer is going to explode!\n") +
		                      QString("(please report the bug *before* going to a safe place, you could rescue others)"), QMessageBox::Ok);
	list = new QListView(qobject_cast<QWidget *>(parent()));
	listModel = new CompletionListModel(list);
    connect(list, SIGNAL(clicked(const QModelIndex&)) , this, SLOT(selectionChanged(const QModelIndex&)));
	list->setModel(listModel);
	list->setFocusPolicy(Qt::NoFocus);
	list->setItemDelegate(new CompletionItemDelegate(list));
	list->setAutoFillBackground(true);
    editor = nullptr;
	workingDir = "/";
    dirReader = nullptr;
    bibReader = nullptr;
    packageList = nullptr;
	widget = new QWidget(qobject_cast<QWidget *>(parent()));
	//widget->setAutoFillBackground(true);
	QVBoxLayout *layout = new QVBoxLayout;
	layout->setSpacing(0);
	tbAbove = new QTabBar();
	tbAbove->setShape(QTabBar::RoundedNorth);
	tbAbove->addTab(tr("typical"));
	tbAbove->addTab(tr("most used"));
    tbAbove->addTab(tr("fuzzy"));
	tbAbove->addTab(tr("all"));
	tbAbove->setToolTip(tr("press shift+space to change view"));
	layout->addWidget(tbAbove);
	tbAbove->hide();
	layout->addWidget(list);
	tbBelow = new QTabBar();
	tbBelow->setShape(QTabBar::RoundedSouth);
	tbBelow->addTab(tr("typical"));
	tbBelow->addTab(tr("most used"));
    tbBelow->addTab(tr("fuzzy"));
	tbBelow->addTab(tr("all"));
	tbBelow->setToolTip(tr("press shift+space to change view"));
	layout->addWidget(tbBelow);
	widget->setLayout(layout);
	widget->setContextMenuPolicy(Qt::PreventContextMenu);
	connect(list, SIGNAL(activated(QModelIndex)), this, SLOT(listClicked(QModelIndex)));
	// todo: change tab when shift+space is pressed ...
	//connect(tbBelow,SIGNAL(currentChanged(int)),this,SLOT(changeView(int)));
	//connect(tbAbove,SIGNAL(currentChanged(int)),this,SLOT(changeView(int)));
}

LatexCompleter::~LatexCompleter()
{
	if (dirReader) {
		dirReader->quit();
		dirReader->wait();
        delete dirReader;
	}
	if (bibReader) {
		bibReader->quit();
        bibReader->wait();
        delete bibReader;
	}
}

void LatexCompleter::changeView(int pos)
{
	completerInputBinding->setMostUsed(pos);
}

void LatexCompleter::listClicked(QModelIndex index)
{

	Q_UNUSED(index)
	if (!completerInputBinding->insertCompletedWord()) {
		editor->insertText("\n");
	}
	completerInputBinding->resetBinding();
}

void LatexCompleter::insertText(QString txt)
{
	if (!isVisible())
		return;
	completerInputBinding->insertText(txt);
	QString cur = completerInputBinding->getCurWord();
	filterList(cur, completerInputBinding->getMostUsed());
}

void LatexCompleter::setAdditionalWords(const QSet<QString> &newwords, CompletionType completionType)
{
	// convert to codesnippets
	CodeSnippetList newWordList;
	for (QSet<QString>::const_iterator i = newwords.constBegin(); i != newwords.constEnd(); ++i) {
		QString str = *i;
		bool isReference = str.startsWith('@');
		if (isReference)
			str = str.mid(1);
		CompletionWord cw(str);
		if (completionType == CT_COMMANDS) {
			cw.index = qHash(str);
			cw.snippetLength = str.length();
			cw.usageCount = isReference ? 2 : 0; // make reference always visible (most used) in completer
			QList<QPair<int, int> >res = config->usage.values(cw.index);
			foreach (const PairIntInt &elem, res) {
				if (elem.first == cw.snippetLength) {
					cw.usageCount = elem.second;
					break;
				}
			}
		} else {
			cw.index = 0;
			cw.usageCount = -2;
			cw.snippetLength = 0;
		}
		newWordList.append(cw);
	}
    std::sort(newWordList.begin(), newWordList.end());
	//
	CodeSnippetList concated;
	if (config && completionType == CT_COMMANDS) concated.unite(config->words);
	//concated.unite(newwords);
	listModel->setBaseWords(concated, newWordList, completionType);
	widget->resize(200, 200);
}
/*!
 * \brief setAdditionalWords from a std::set<QString>
 * The advantage is that a std::set is already sorted.
 * \param newwords
 * \param completionType
 */
void LatexCompleter::setAdditionalWords(const std::set<QString> &newwords, CompletionType completionType)
{
    // convert to codesnippets
    CodeSnippetList newWordList;
    for (std::set<QString>::const_iterator i = newwords.cbegin(); i != newwords.cend(); ++i) {
        QString str = *i;
        bool isReference = str.startsWith('@');
        if (isReference)
            str = str.mid(1);
        CompletionWord cw(str);
        if (completionType == CT_COMMANDS) {
            cw.index = qHash(str);
            cw.snippetLength = str.length();
            cw.usageCount = isReference ? 2 : 0; // make reference always visible (most used) in completer
            QList<QPair<int, int> >res = config->usage.values(cw.index);
            foreach (const PairIntInt &elem, res) {
                if (elem.first == cw.snippetLength) {
                    cw.usageCount = elem.second;
                    break;
                }
            }
        } else {
            cw.index = 0;
            cw.usageCount = -2;
            cw.snippetLength = 0;
        }
        newWordList.append(cw);
    }

    CodeSnippetList concated;
    if (config && completionType == CT_COMMANDS) concated.unite(config->words);
    //concated.unite(newwords);
    listModel->setBaseWords(concated, newWordList, completionType);
    widget->resize(200, 200);
}

void LatexCompleter::setAdditionalWords(const CodeSnippetList &newwords, CompletionType completionType)
{
	CodeSnippetList concated;
	if (config && completionType == CT_COMMANDS) concated.unite(config->words);
	//concated.unite(newwords);
	listModel->setBaseWords(concated, newwords, completionType);
	widget->resize(200, 200);
}

void LatexCompleter::setKeyValWords(const QString &name, const QSet<QString> &newwords)
{
	listModel->setKeyValWords(name, newwords);
}

void LatexCompleter::setContextWords(const QSet<QString> &newwords, const QString &context)
{
	listModel->setContextWords(newwords, context);
}

/*!
 * \brief adjust width and position of the widget.
 * \return BelowCursor if the calculated position is below the cursor, otherwise AboveCursor
 */
void LatexCompleter::adjustWidget()
{
	// adjust width
	int newWordMax = 0;
	QFont f = QApplication::font();
	f.setItalic(true);
	QFontMetrics fm(f);
	const QList<CompletionWord> &words = listModel->getWords();
	for (int i = 0; i < words.size(); i++) {
		if (words[i].lines.empty() || words[i].placeHolders.empty()) continue;
		int temp = UtilsUi::getFmWidth(fm, words[i].lines[0]) + words[i].placeHolders[0].size() + 10;
		if (temp > newWordMax) newWordMax = temp;
	}
	maxWordLen = newWordMax;
    int width = qMax(400, maxWordLen);
	QScrollBar *bar = list->verticalScrollBar();
	if (bar && bar->isVisible()) {
		width += bar->width() * 4;
	}
	widget->resize(width, 200);

	// adjust position
    QPointF offset;
	bool isAboveCursor = false;
	if (editor->getPositionBelowCursor(offset, widget->width(), widget->height(), isAboveCursor))
        widget->move(editor->mapTo(qobject_cast<QWidget *>(parent()), offset.toPoint()));

	// adjust visible tab bar depending on location relative to cursor
	QTabBar *tbOn = (isAboveCursor) ? tbAbove : tbBelow;
	QTabBar *tbOff = (isAboveCursor) ? tbBelow : tbAbove;
	disconnect(tbOn, SIGNAL(currentChanged(int)), this, SLOT(changeView(int)));
	disconnect(tbOff, SIGNAL(currentChanged(int)), this, SLOT(changeView(int)));
	tbOn->show();
	tbOff->hide();
	tbOn->setCurrentIndex(config->preferedCompletionTab);
	connect(tbOn, SIGNAL(currentChanged(int)), this, SLOT(changeView(int)));
}

void LatexCompleter::updateAbbreviations()
{
	REQUIRE(config);
	QList<CompletionWord> wordsAbbrev;
	foreach (const Macro &macro, config->userMacros) {
		if (macro.abbrev.isEmpty() || macro.snippet().isEmpty())
			continue;
		//CompletionWord cw(abbr);
		// for compatibility to texmaker ...
		CompletionWord cw(macro.snippet());
		// <!compatibility>
		cw.word = macro.abbrev;
		cw.sortWord = makeSortWord(cw.word);
		if (macro.name == "")
			cw.setName(macro.abbrev + tr(" (Usertag)"));
		else 
			cw.setName(macro.abbrev + " (" + macro.name + ")");
		wordsAbbrev << cw;
	}
	listModel->setAbbrevWords(wordsAbbrev);
}

void LatexCompleter::setLatexReference(LatexReference *ref) { latexReference = ref; }

LatexReference *LatexCompleter::getLatexReference() { return latexReference; }

void LatexCompleter::complete(QEditor *newEditor, const CompletionFlags &flags)
{
	Q_ASSERT(list);
	Q_ASSERT(listModel);
	Q_ASSERT(completerInputBinding);

    bool alreadyActive=completerInputBinding->isActive(); // called with already open completer

	forcedRef = flags & CF_FORCE_REF;
	forcedGraphic = flags & CF_FORCE_GRAPHIC;
	forcedCite = flags & CF_FORCE_CITE;
	forcedPackage = flags & CF_FORCE_PACKAGE;
	forcedKeyval = flags & CF_FORCE_KEYVAL;
	forcedSpecialOption = flags & CF_FORCE_SPECIALOPTION;
	forcedLength = flags & CF_FORCE_LENGTH;
	startedFromTriggerKey = !(flags & CF_FORCE_VISIBLE_LIST);
    disable_mu_sorting = flags & CF_DISABLE_MU_SORTING;
    listModel->setDisableMostUsedSorting(disable_mu_sorting);
	if (editor != newEditor) {
		if (editor) disconnect(editor, SIGNAL(destroyed()), this, SLOT(editorDestroyed()));
		if (newEditor) connect(newEditor, SIGNAL(destroyed()), this, SLOT(editorDestroyed()));
		editor = newEditor;
	}
	if (!editor) return;
	QDocumentCursor c = editor->cursor();
	if (!c.isValid()) return;
	/*int phId=editor->currentPlaceHolder();
	if(phId>-1 && phId<editor->placeHolderCount()){
		PlaceHolder ph=editor->getPlaceHolder(phId);
		if(ph.cursor.isWithinSelection(c) && !ph.mirrors.isEmpty()){
			editor->removePlaceHolder(phId);
		}
	}*/
	if (editor->cursorMirrorCount() > 0) return; // completer does not handle cursor mirrors. It would just remove them. -> don't use completer

	if (c.hasSelection()) {
		c.setColumnNumber(qMax(c.columnNumber(), c.anchorColumnNumber()));
		editor->setCursor(c);
	}

	//disable auto close char while completer is open
    if(!alreadyActive)
        editorAutoCloseChars = editor->flag(QEditor::AutoCloseChars); // don't change again from open completer (and therin changed flag, see #1347)

    editor->setFlag(QEditor::AutoCloseChars, false);

    completerInputBinding->setMostUsed(config->preferedCompletionTab, true);
    bool handled = false;
    if (forcedGraphic) {
        if (!dirReader) {
            dirReader = new directoryReader(this);
            connect(dirReader, &directoryReader::directoryLoaded, this, &LatexCompleter::directoryLoaded);
            connect(this, SIGNAL(setDirectoryForCompletion(QString)), dirReader, SLOT(readDirectory(QString)));
            dirReader->start();
        }
        QSet<QString> files;
        listModel->setBaseWords(files, CT_NORMALTEXT);
        listModel->baselist = listModel->wordsText;
        handled = true;
    }
	if (forcedCite) {
		listModel->baselist = listModel->wordsCitations;
		handled = true;
	}
	if (forcedRef) {
		listModel->baselist = listModel->wordsLabels;
		handled = true;
	}
	if (forcedPackage) {
		listModel->setBaseWords(*packageList, CT_NORMALTEXT);
		listModel->baselist = listModel->wordsText;
		handled = true;
	}
	if (forcedKeyval) {
		listModel->baselist.clear();
		handled = true;
		foreach (const CompletionWord &cw, listModel->keyValLists.value(workingDir)) {
			if (cw.word.startsWith("#")) {
				if (cw.word == "#L") {
					// complete with length
					forcedLength = true;
                    forcedKeyval = false;
                    handled = false;
                    break;
                }
                handled=true;
                break;
			}
			if (cw.word.startsWith('%')) {
				QString specialList = cw.word;
				if (listModel->contextLists.contains(specialList)) {
					listModel->baselist << listModel->contextLists.value(specialList);
					QList<CompletionWord>::iterator middle = listModel->baselist.end() - listModel->contextLists.value(specialList).length();
					std::inplace_merge(listModel->baselist.begin(), middle, listModel->baselist.end());
				}
			} else {
				// nothing special, simply add
                QList<CompletionWord>::iterator it;
                it = std::lower_bound(listModel->baselist.begin(), listModel->baselist.end(), cw);
				listModel->baselist.insert(it, cw); // keep sorting
			}
		}


	}
	if (forcedSpecialOption) {
		listModel->baselist = listModel->contextLists.value(workingDir);

		handled = true;
	}
	if (!handled) {
		if (flags & CF_NORMAL_TEXT) listModel->baselist = listModel->wordsText;
		else listModel->baselist = listModel->wordsCommands;
		listModel->baselist << listModel->wordsAbbrev;
		QList<CompletionWord>::iterator middle = listModel->baselist.end() - listModel->wordsAbbrev.length();
		std::inplace_merge(listModel->baselist.begin(), middle, listModel->baselist.end());
	}
	if ( editor->currentPlaceHolder() >= 0 && editor->currentPlaceHolder() < editor->placeHolderCount() ) {
		PlaceHolder ph = editor->getPlaceHolder(editor->currentPlaceHolder());
		if (ph.mirrors.count() > 0)
			listModel->setEnvironMode(true);
	}
	//qSort(listModel->baselist.begin(),listModel->baselist.end());
	if (c.previousChar() != '\\' || (flags & CF_FORCE_VISIBLE_LIST)) {
		int start = c.columnNumber() - 1;
		if (flags & CF_NORMAL_TEXT) start = 0;
		if (flags & CF_FORCE_GRAPHIC) start = 0;
		QString eow = "~!@#$%^&*()_+{}|:\"<>?,./;[]-= \n\r`+�\t";
		if (flags & CF_FORCE_CITE) {
			// the prohibited chars in bibtex keys are not well documented and differ among bibtex tools
			// this is what JabRef uses (assuming they have a good understanding due to the maturity of the project):
			eow = "\n\r\t #{}\\\"~,^'";
		}
		if (flags & CF_FORCE_GRAPHIC) {
			eow.remove("/");
			eow.remove("\\");
			eow.remove(".");
			eow.remove(":");
			eow.remove("_");
            eow.remove("-");
		}
		if (flags & CF_FORCE_PACKAGE) {
			eow.remove("_");
            eow.remove("-");
		}
        if (flags & CF_FORCE_EXPL3) {
            eow.remove("_");
            eow.remove(":");
        }
        if (flags & CF_FORCE_KEYVAL) {
            eow.remove(" ");
            eow.remove("-");
            eow.remove("/");
        }
		if (flags == CF_FORCE_VISIBLE_LIST)
			eow.remove("{");
		if (flags & CF_FORCE_REF) eow = "[]{}\\";
		if (flags & CF_FORCE_REFLIST) eow = "[]{}\\,";
		QString lineText = c.line().text();
        int i = c.columnNumber() - 1;
        if(i>lineText.length()){
            i=lineText.length()-1; // avoid crash
        }
        for (; i >= 0; i--) {
			if ((lineText.at(i) == QChar('\\')) && !(flags & CF_FORCE_GRAPHIC)) {
				start = i;
				break;
			} else if (eow.contains(lineText.at(i))) {
				if (flags & CF_NORMAL_TEXT) start = i + 1;
				if (flags & CF_FORCE_GRAPHIC) start = i + 1;
				if (flags & CF_FORCE_CITE) start = i + 1;
				if (flags & CF_FORCE_REF) start = i + 1;
                if (flags & CF_FORCE_PACKAGE) start = i + 1;
                if (flags & CF_FORCE_KEYVAL){
                    ++i;
                    while(i<c.columnNumber() && lineText.at(i)==' '){
                        ++i;
                    }
                    start = i;
                }
				if (flags & CF_FORCE_SPECIALOPTION) start = i + 1;
				break;
			}
		}
        if(i<0){
            start=0; // take complete text if no eow is detected (#3966)
            // skip spaces at the beginning
            i = c.columnNumber();
            while(start<lineText.length() && lineText.at(start)==' ' && start<i){
                ++start;
            }
        }
		QString path;
		if (flags & CF_FORCE_GRAPHIC) {
			QString fn = lineText.mid(start, c.columnNumber() - start);
            int lastIndex = fn.lastIndexOf("/");
			if (lastIndex >= 0)
				start = start + lastIndex + 1;
			if (fn.isEmpty())
                fn = workingDir + "/";

            QFileInfo fi(QDir(workingDir),fn);
			path = fi.absolutePath();
            currentPath=path;
		}
		completerInputBinding->bindTo(editor, this, true, start);
		adjustWidget();

		if ((flags & CF_FORCE_GRAPHIC) && !path.isEmpty()) {
			emit setDirectoryForCompletion(path);
		}
	} else completerInputBinding->bindTo(editor, this, false, c.columnNumber() - 1);

	if (completerInputBinding->getMostUsed() == 1 && countWords() == 0) { // if prefered list is empty, take next more extensive one
        setTab(0); // typical
		adjustWidget();
	}
	if (completerInputBinding->getMostUsed() && countWords() == 0) {
        setTab(3); // all
		adjustWidget();
	}

	if (completerInputBinding->getMostUsed() == config->preferedCompletionTab)
		completerInputBinding->setMostUsed(config->preferedCompletionTab, false);

	//line.document()->cursor(0,0).insertText(QString::number(offset.x())+":"+QString::number(offset.y()));
	connect(editor, SIGNAL(cursorPositionChanged()), this, SLOT(cursorPositionChanged()));

	completerInputBinding->autoOverridenText = (flags & CF_OVERRIDEN_BACKSLASH) ? "\\" : "";

    if (config && config->completeCommonPrefix && alreadyActive) completerInputBinding->completeCommonPrefix(); // only complete common prefix if the completer was visible when called
}

void LatexCompleter::directoryLoaded(QString , QSet<QString> content)
{
	listModel->setBaseWords(content, CT_NORMALTEXT);
	listModel->baselist = listModel->wordsText;
	//setTab(2);
    completerInputBinding->setMostUsed(3); // all
	adjustWidget();
}

bool LatexCompleter::acceptTriggerString(const QString &trigger)
{
	return trigger == "\\" && (!config || config->enabled);
}

void LatexCompleter::setConfig(LatexCompleterConfig *config)
{
	REQUIRE(config);
	this->config = config;
	listModel->setConfig(config);

	QFont f(QApplication::font());
	f.setPointSize( f.pointSize() * config->tabRelFontSizePercent / 100);
	tbAbove->setFont(f);
	tbBelow->setFont(f);
}

LatexCompleterConfig *LatexCompleter::getConfig() const
{
	return config;
}

LatexParser &LatexCompleter::getLatexParser() const
{
    return const_cast<LatexParser &>(latexParser);
}

void LatexCompleter::setPackageList(std::set<QString> *lst)
{
	packageList = lst;
}

int LatexCompleter::countWords()
{
	return listModel->getWords().count();
}

void LatexCompleter::setTab(int index)
{
    Q_ASSERT(index >= 0 && index < 4);
	if (tbBelow->isVisible())
		tbBelow->setCurrentIndex(index);
	if (tbAbove->isVisible())
		tbAbove->setCurrentIndex(index);
}

bool LatexCompleter::isCurrentWordUserConstruct()
{
    if (list->isVisible() && list->currentIndex().isValid()){
        QVariant v = list->model()->data(list->currentIndex(), Qt::DisplayRole);
        if (!v.isValid() || !v.canConvert<CompletionWord>()) return false;
        CompletionWord cw = v.value<CompletionWord>();
        return cw.type == CompletionWord::userConstruct;
    }
    return false;
}

void LatexCompleter::filterList(QString word, int showMostUsed)
{
	QString cur = ""; //needed to preserve selection
	if (list->isVisible() && list->currentIndex().isValid())
		cur = list->model()->data(list->currentIndex(), Qt::DisplayRole).toString();
	CodeSnippet::Type type = CodeSnippet::none;
	if (forcedLength)
		type = CodeSnippet::length;
	listModel->filterList(word, showMostUsed, false, type);
	if (cur != "") {
		int p = listModel->getWords().indexOf(cur);
		if (p >= 0) list->setCurrentIndex(list->model()->index(p, 0, QModelIndex()));
	}
}

bool LatexCompleter::acceptChar(QChar c, int pos)
{
	//always accept alpha numerical characters
	if (((c >= QChar('a')) && (c <= QChar('z'))) ||
	        ((c >= QChar('A')) && (c <= QChar('Z'))) ||
	        ((c >= QChar('0')) && (c <= QChar('9')))) return true;
	if (pos <= 1) return false;
	if (listModel->isNextCharPossible(c))
		return true; //only accept non standard character, if one of the current words contains it
	return false;
}

void LatexCompleter::cursorPositionChanged()
{
	if (!completerInputBinding || !completerInputBinding->isActive()) {
		disconnect(editor, SIGNAL(cursorPositionChanged()), this, SLOT(cursorPositionChanged()));
		return;
	}
	completerInputBinding->cursorPositionChanged(editor);
}

//called when item is clicked, more important: normal (not signal/slot) called when completerbinding change selection
void LatexCompleter::selectionChanged(const QModelIndex &index)
{
	// Note on tooltip usage: It is not possible to hide and shortly afterwards reshow a tooltip
	// with the same text (there's some interference between the internal hideTimer of the tooltip and
	// the internal tooltip-reuse when QToolTip::showText() for the same text. As a result, the tooltip
	// does not persist. This is a Qt-Bug.
	// Workaround: we cannot QToolTip::hideText generally and QToolTip::showText as needed. Therefore we have to
	// hide the tooltip in every single exit branch of the function that does not show the tooltip.
	if (!index.isValid() || !isVisible()) {
		QToolTip::hideText();
		return;
	}
    if (config->tooltipPreview && forcedGraphic) { // picture preview even if help is disabled (maybe the same for cite/ref ?)
        QString path=currentPath;
        if(path.isEmpty()) path=workingDir;
        QString fn = path + QDir::separator() + listModel->words[index.row()].word;
		QToolTip::hideText();
		emit showImagePreview(fn);
		return;
	}

	if (index.row() < 0 || index.row() >= listModel->words.size()) {
		QToolTip::hideText();
		return;
	}
	if (config->tooltipPreview && forcedSpecialOption && workingDir == "%color") {
		QToolTip::hideText();
		QString text;
		text = QString("{\\color{%1} \\rule{1cm}{1cm}}").arg(listModel->words[index.row()].word);
		emit showPreview(text);
		return;
	}
    QRegularExpression wordrx("^\\\\([^ {[*]+|begin\\{[^ {}]+)");
    QRegularExpressionMatch wordrxMatch = wordrx.match(listModel->words[index.row()].word);
    if (!forcedCite && !wordrxMatch.hasMatch()) {
		QToolTip::hideText();
		return;
	}
    QString cmd = wordrxMatch.captured(0);
	QString topic;
	if (config->tooltipPreview && latexParser.possibleCommands["%ref"].contains(cmd)) {
		QString value = listModel->words[index.row()].word;
		int i = value.indexOf("{");
		value.remove(0, i + 1);
		i = value.indexOf("}");
		value = value.left(i);
		LatexDocument *document = qobject_cast<LatexDocument *>(editor->document());
		int cnt = document->countLabels(value);
		topic = "";
		if (cnt == 0) {
			topic = tr("label missing!");
		} else if (cnt > 1) {
			topic = tr("label defined multiple times!");
		} else {
			QMultiHash<QDocumentLineHandle *, int> result = document->getLabels(value);
            if(!result.isEmpty()){
                QDocumentLineHandle *mLine = result.keys().constFirst();
                int l = mLine->document()->indexOf(mLine);
                if (mLine->document() != editor->document()) {
                    //LatexDocument *doc=document->parent->findDocument(mLine->document());
                    LatexDocument *doc = qobject_cast<LatexDocument *>(mLine->document());
                    Q_ASSERT_X(doc, "missing latexdoc", "qdoc is not latex document !");
                    if (doc) topic = tr("<p style='white-space:pre'><b>Filename: %1</b>\n").arg(doc->getFileName());
                }
                for (int i = qMax(0, l - 2); i < qMin(mLine->document()->lines(), l + 3); i++) {
                    topic += mLine->document()->line(i).text().left(80);
                    if (mLine->document()->line(i).text().length() > 80) topic += "...";
                    if (i < l + 2) topic += "\n";
                }
            }
		}
	} else if (config->tooltipPreview && (forcedCite || latexParser.possibleCommands["%cite"].contains(cmd))) {
		QToolTip::hideText();
		QString value = listModel->words[index.row()].word;
        const QRegularExpression re{"{([^}]+?)}"};
        const QRegularExpressionMatch match = re.match(value);
        if(match.hasMatch()){
            value = match.captured(1);
        }
        LatexDocument *document = qobject_cast<LatexDocument *>(editor->document());
		if (!bibReader) {
			bibReader = new bibtexReader(this);
			connect(bibReader, SIGNAL(sectionFound(QString)), this, SLOT(bibtexSectionFound(QString)));
            connect(this, SIGNAL(searchBibtexSection(QString,QString)), bibReader, SLOT(searchSection(QString,QString)));
			bibReader->start();
		}
		QString file = document->findFileFromBibId(value);
		if (!file.isEmpty())
			emit searchBibtexSection(file, value);
		return;
	} else {
		if (latexReference && config->tooltipHelp)
			topic = latexReference->getTextForTooltip(cmd);
		if (topic.isEmpty()) {
			QToolTip::hideText();
			return;
		}
	}
	showTooltip(topic);
}

void LatexCompleter::showTooltip(QString text)
{
	if (!isVisible()) {
		QToolTip::hideText();
		return;
	}
	QModelIndex index = list->currentIndex();
	QRect r = list->visualRect(index);
	QDocumentCursor c = editor->cursor();
    qreal lineHeight = c.line().document()->getLineSpacing();
	QPoint pos = list->mapToGlobal(QPoint(list->width(), r.top() - lineHeight));
	showTooltipLimited(pos, text, list->width());
}

void LatexCompleter::setFilter(QString filter)
{
    listModel->setEnvironmentFilter(filter);
    listModel->curWord = ""; // force filter update
}

void LatexCompleter::editorDestroyed()
{
    editor = nullptr;
}

void LatexCompleter::bibtexSectionFound(QString content)
{
	showTooltip(content);
}

//ends completion (closes the list) and returns true if there was any
bool LatexCompleter::close()
{
	if (completerInputBinding->isActive()) {
		completerInputBinding->simpleRestoreAutoOverride();
		completerInputBinding->resetBinding();
		widget->setVisible(false);
		listModel->curWord = "";
		return true;
	} else return false;
}

bool LatexCompleter::isVisible() { return list->isVisible(); }

void LatexCompleterConfig::setFiles(const QStringList &newFiles)
{
	files = newFiles;
}

const QStringList &LatexCompleterConfig::getLoadedFiles() const
{
	return files;
}

bool LatexCompleter::existValues()
{
	return listModel->keyValLists.value(workingDir).size() > 0;
}

void LatexCompleter::setWorkPath(const QString cwd) { workingDir = cwd; }

bool LatexCompleter::completingGraphic() { return forcedGraphic; }

bool LatexCompleter::completingKey() { return forcedKeyval; }
