/*
* KmPlot - a math. function plotter for the KDE-Desktop
*
* Copyright (C) 2004  Fredrik Edemar <f_edemar@linux.se>
*               2006  David Saxton <david@bluehaze.org>
*               
* This file is part of the KDE Project.
* KmPlot is part of the KDE-EDU Project.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* 
* This program 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 General Public License for more details.
* 
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*
*/

#include "kparametereditor.h"

#include <QDebug>
#include <QDialogButtonBox>
#include <QFile>
#include <QFileDialog>
#include <QListWidget>
#include <QPushButton>
#include <QTemporaryFile>
#include <QTextStream>
#include <QVBoxLayout>

#include <KConfigGroup>
#include <KIO/StoredTransferJob>
#include <KJobWidgets>
#include <KMessageBox>

#include "maindlg.h"

#include <assert.h>

class ParameterValueList;

KParameterEditor::KParameterEditor( QList<Value> *l, QWidget *parent )
	: QDialog( parent ),
	  m_parameter(l)
{
	m_mainWidget = new QParameterEditor( this );
	setWindowTitle( i18nc("@title:window", "Parameter Editor") );
	QVBoxLayout *mainLayout = new QVBoxLayout;
	setLayout(mainLayout);
	mainLayout->addWidget(m_mainWidget);

	QDialogButtonBox *buttonBox = new QDialogButtonBox(QDialogButtonBox::Ok|QDialogButtonBox::Cancel);
	QPushButton *okButton = buttonBox->button(QDialogButtonBox::Ok);
	okButton->setDefault(true);
	okButton->setShortcut(Qt::CTRL | Qt::Key_Return);
	connect(buttonBox, &QDialogButtonBox::accepted, this, &KParameterEditor::accept);
	connect(buttonBox, &QDialogButtonBox::rejected, this, &KParameterEditor::reject);
	mainLayout->addWidget(buttonBox);

	mainLayout->setContentsMargins( 0, 0, 0, 0 );
	
	m_mainWidget->cmdNew->setIcon( QIcon::fromTheme("document-new" ) );
	m_mainWidget->cmdDelete->setIcon( QIcon::fromTheme("edit-delete" ) );
	m_mainWidget->moveUp->setIcon( QIcon::fromTheme("go-up") );
	m_mainWidget->moveDown->setIcon( QIcon::fromTheme("go-down") );
	m_mainWidget->cmdImport->setIcon( QIcon::fromTheme("document-open") );
	m_mainWidget->cmdExport->setIcon( QIcon::fromTheme("document-save") );
	
	m_mainWidget->list->setFocusPolicy( Qt::NoFocus );
	
	connect(m_mainWidget->value, &EquationEdit::upPressed, this, &KParameterEditor::prev);
	connect(m_mainWidget->value, &EquationEdit::downPressed, this, &KParameterEditor::next);
	
	for ( const Value &v : qAsConst(*m_parameter) )
		m_mainWidget->list->addItem( v.expression() );
	
	connect(m_mainWidget->cmdNew, &QPushButton::clicked, this, &KParameterEditor::cmdNew_clicked);
	connect(m_mainWidget->cmdDelete, &QPushButton::clicked, this, &KParameterEditor::cmdDelete_clicked);
	connect(m_mainWidget->moveUp, &QPushButton::clicked, this, &KParameterEditor::moveUp);
	connect(m_mainWidget->moveDown, &QPushButton::clicked, this, &KParameterEditor::moveDown);
	connect(m_mainWidget->cmdImport, &QPushButton::clicked, this, &KParameterEditor::cmdImport_clicked);
	connect(m_mainWidget->cmdExport, &QPushButton::clicked, this, &KParameterEditor::cmdExport_clicked);
	connect(m_mainWidget->list, &QListWidget::currentItemChanged, this, &KParameterEditor::selectedConstantChanged);
	
	connect(m_mainWidget->value, &EquationEdit::textEdited, this, &KParameterEditor::saveCurrentValue);
	connect(m_mainWidget->value, &EquationEdit::textChanged, this, &KParameterEditor::checkValueValid);
	connect(m_mainWidget->value, &EquationEdit::returnPressed, m_mainWidget->cmdNew, &QAbstractButton::click);
	
	checkValueValid();
	
	m_mainWidget->value->setFocus();
}

KParameterEditor::~KParameterEditor()
{
}


void KParameterEditor::accept()
{
	qDebug() << "saving\n";
	m_parameter->clear();
	QString item_text;
	for ( int i = 0; i < m_mainWidget->list->count(); i++ )
	{
		item_text = m_mainWidget->list->item(i)->text();
		if ( !item_text.isEmpty() )
		{
			Value value;
			if ( value.updateExpression( item_text ) )
				m_parameter->append( value );
		}
	}
	
	QDialog::accept();
}


void KParameterEditor::moveUp()
{
	int current = m_mainWidget->list->currentRow();
	
	if ( current == 0 )
		return;
	
	QListWidgetItem * item = m_mainWidget->list->takeItem( current-1 );
	m_mainWidget->list->insertItem( current, item );
}


void KParameterEditor::moveDown()
{
	int current = m_mainWidget->list->currentRow();
	
	if ( current == m_mainWidget->list->count() - 1 )
		return;
	
	QListWidgetItem * item = m_mainWidget->list->takeItem( current+1 );
	m_mainWidget->list->insertItem( current, item );
}


void KParameterEditor::cmdNew_clicked()
{
	QListWidgetItem * item = new QListWidgetItem( m_mainWidget->list );
	item->setText( "0" );
	m_mainWidget->list->setCurrentItem( item );
	m_mainWidget->value->setFocus();
	m_mainWidget->value->selectAll();
}


void KParameterEditor::prev()
{
	int current = m_mainWidget->list->currentRow();
	if ( current > 0 )
		m_mainWidget->list->setCurrentRow( current-1 );
}


void KParameterEditor::next()
{
	int current = m_mainWidget->list->currentRow();
	if ( current < m_mainWidget->list->count()-1 )
		m_mainWidget->list->setCurrentRow( current+1 );
	else
		cmdNew_clicked();
}


void KParameterEditor::selectedConstantChanged( QListWidgetItem * current )
{
	m_mainWidget->cmdDelete->setEnabled( current != 0 );
	m_mainWidget->value->setText( current ? current->text() : QString() );
	m_mainWidget->value->selectAll();
}


void KParameterEditor::cmdDelete_clicked()
{
	QListWidgetItem * item = m_mainWidget->list->currentItem();
	if ( !item )
		return;
	
	m_mainWidget->value->clear();
	m_mainWidget->list->takeItem( m_mainWidget->list->currentRow() );
	delete item;
	
	m_mainWidget->cmdDelete->setEnabled( m_mainWidget->list->currentItem() != 0 );
}


void KParameterEditor::saveCurrentValue()
{
	QListWidgetItem * current = m_mainWidget->list->currentItem();
	if ( !current )
		current = new QListWidgetItem( m_mainWidget->list );
	
	current->setText( m_mainWidget->value->text() );
	m_mainWidget->list->setCurrentItem( current );
}


bool KParameterEditor::checkValueValid()
{
	QString valueText = m_mainWidget->value->text();
	Parser::Error error;
	(double) XParser::self()->eval( valueText, & error );
	bool valid = (error == Parser::ParseSuccess);
	m_mainWidget->valueInvalidLabel->setVisible( !valueText.isEmpty() && !valid );
	return valid;
}


void KParameterEditor::cmdImport_clicked()
{
	QUrl url = QFileDialog::getOpenFileUrl(this, i18n("Open Parameter File"), QUrl(), i18n("Plain Text File (*.txt)"));
	if ( url.isEmpty() )
		return;

        if (!MainDlg::fileExists( url ) )
        {
			KMessageBox::sorry(0,i18n("The file does not exist."));
			return;
        }

	bool verbose = false;
	QFile file;
	if ( !url.isLocalFile() )
	{
		KIO::StoredTransferJob *transferjob = KIO::storedGet (url);
		KJobWidgets::setWindow(transferjob, 0);
		if ( !transferjob->exec() ) {
			KMessageBox::sorry(0,i18n("An error appeared when opening this file: %1", transferjob->errorString() ));
			return;
		}
		QTemporaryFile tmpfile;
		tmpfile.setAutoRemove(false);
		tmpfile.open();
		tmpfile.write(transferjob->data());
		file.setFileName(tmpfile.fileName());
		tmpfile.close();
	}
	else
		file.setFileName(url.toLocalFile() );

	if ( file.open(QIODevice::ReadOnly) )
	{
		QTextStream stream(&file);
		QString line;
		for( int i=1; !stream.atEnd();i++ )
		{
			line = stream.readLine();
			if (line.isEmpty())
				continue;
			
			Parser::Error error;
			XParser::self()->eval( line, & error );
			if ( error == Parser::ParseSuccess )
			{
				if ( !checkTwoOfIt(line) )
				{
					m_mainWidget->list->addItem(line);
				}
			}
			else if ( !verbose)
			{
				if ( KMessageBox::warningContinueCancel(this,i18n("Line %1 is not a valid parameter value and will therefore not be included. Do you want to continue?", i) ) == KMessageBox::Cancel)
				{
					file.close();
					QFile::remove( file.fileName() );
					return;
				}
				else if (KMessageBox::warningYesNo(this,i18n("Would you like to be informed about other lines that cannot be read?"), QString(), KGuiItem(i18n("Get Informed")), KGuiItem(i18n("Ignore Information")) ) == KMessageBox::No)
					verbose = true;
			}
		}
		file.close();
	}
	else
		KMessageBox::sorry(0,i18n("An error appeared when opening this file"));
        
        if ( !url.isLocalFile() )
                QFile::remove( file.fileName() );
}


void KParameterEditor::cmdExport_clicked()
{
	if ( !m_mainWidget->list->count() )
                return;
	QUrl url = QFileDialog::getSaveFileUrl(this, i18n("Save File"), QUrl(), i18n("Plain Text File (*.txt)"));
	if ( url.isEmpty() )
		return;

	if( !MainDlg::fileExists( url ) || KMessageBox::warningContinueCancel( this, i18n( "A file named \"%1\" already exists. Are you sure you want to continue and overwrite this file?", url.toDisplayString()), i18n( "Overwrite File?" ), KStandardGuiItem::overwrite() ) == KMessageBox::Continue )
	{
		if ( !url.isLocalFile() )
		{
			QTemporaryFile tmpfile;

			if (tmpfile.open() )
			{
				QTextStream stream(&tmpfile);
				for ( int i = 0; i < m_mainWidget->list->count(); i++ )
				{
					QListWidgetItem * it = m_mainWidget->list->item( i );
					stream << it->text();
					if ( i < m_mainWidget->list->count()-1 )
						stream << '\n'; //only write a new line if there are more text
				}
				stream.flush();
			}
			else
				KMessageBox::sorry(0,i18n("An error appeared when saving this file"));

			Q_CONSTEXPR int permission = -1;
			QFile file(tmpfile.fileName());
			file.open(QIODevice::ReadOnly);
			KIO::StoredTransferJob *putjob = KIO::storedPut(file.readAll(), url, permission, KIO::JobFlag::Overwrite);
			if (!putjob->exec()) {
				KMessageBox::sorry(0,i18n("An error appeared when saving this file"));
				return;
			}
			file.close();
		}
		else
		{
			QFile file;
			qDebug() << "url.path()="<<url.toLocalFile();
			file.setFileName(url.toLocalFile());
			if (file.open( QIODevice::WriteOnly ) )
			{
				QTextStream stream(&file);
				for ( int i = 0; i < m_mainWidget->list->count(); i++ )
				{
					QListWidgetItem * it = m_mainWidget->list->item( i );
					stream << it->text();
					if ( i < m_mainWidget->list->count()-1 )
						stream << '\n'; //only write a new line if there are more text
				}
				file.close();
			}
                        else
				KMessageBox::sorry(0,i18n("An error appeared when saving this file"));
                }
        }


}


bool KParameterEditor::checkTwoOfIt(const QString & text)
{
	return !m_mainWidget->list->findItems(text,Qt::MatchExactly).isEmpty();
}
