#include "IStudyWindow.h"

#include <QCloseEvent>
#include <QMessageBox>

#include "IStudyModel.h"
#include "CardSideView.h"
#include "CardEditDialog.h"
#include "../dictionary/Dictionary.h"
#include "../dictionary/CardPack.h"
#include "../main-view/MainWindow.h"

const int IStudyWindow::AnsButtonPage = 0;
const int IStudyWindow::AnsLabelPage = 1;
const int IStudyWindow::CardPage = 0;
const int IStudyWindow::MessagePage = 1;

IStudyWindow::IStudyWindow(IStudyModel* aModel , QString aStudyName, QWidget *aParent):
    m_model( aModel ), curCard( NULL ), state(StateAnswerHidden), m_studyName( aStudyName ),
    m_parentWidget( aParent ), m_cardEditDialog( NULL )
{
    setMinimumWidth(MinWidth);
    setMaximumWidth(MaxWidth);
    setAttribute( Qt::WA_DeleteOnClose );
    connect( m_model, SIGNAL(nextCardSelected()), SLOT(showNextCard()) );
    connect( m_model, SIGNAL(curCardUpdated()), SLOT(updateCurCard()) );
}

IStudyWindow::~IStudyWindow()
{
    delete m_model;
}

void IStudyWindow::OnDictionaryRemoved()
{
    close();
}

void IStudyWindow::createUI()
{
    centralStackedLt = new QStackedLayout;
    centralStackedLt->addWidget(createWrapper(createCardView()));
    centralStackedLt->addWidget(createWrapper(createMessageLayout()));
    centralStackedLt->setCurrentIndex(CardPage);
    connect(centralStackedLt, SIGNAL(currentChanged(int)), SLOT(updateToolBarVisibility(int)));

    QVBoxLayout* mainLayout = new QVBoxLayout;
    mainLayout->addLayout(createUpperPanel());
    mainLayout->addLayout(centralStackedLt);
    mainLayout->addLayout(createLowerPanel());
    setLayout(mainLayout);

    ReadSettings();
}

QWidget* IStudyWindow::createWrapper(QBoxLayout* layout)
{
    QWidget* widget = new QWidget;
    widget->setLayout(layout);
    return widget;
}

QVBoxLayout* IStudyWindow::createMessageLayout()
{
    messageLabel = createMessageLabel();

    QVBoxLayout* lt = new QVBoxLayout;
    lt->setContentsMargins(QMargins());
    lt->addStretch();
    lt->addWidget(messageLabel);
    lt->addStretch();
    lt->addWidget(createClosePackButton(), 0, Qt::AlignHCenter);
    lt->addStretch();
    return lt;
}

QLabel* IStudyWindow::createMessageLabel()
{
    QLabel* label = new QLabel;
    label->setAutoFillBackground(true);
    label->setPalette(QPalette("#fafafa"));
    label->setWordWrap(true);
    label->setFrameStyle(QFrame::StyledPanel);
    label->setMinimumHeight(200);
    return label;
}

QPushButton* IStudyWindow::createClosePackButton()
{
    QPushButton* button = new QPushButton(tr("Close this pack"));
    button->setFixedSize(BigButtonWidth, BigButtonHeight);
    connect(button, SIGNAL(clicked()), SLOT(close()));
    return button;
}

QHBoxLayout* IStudyWindow::createUpperPanel()
{
    editCardBtn = createEditCardButton();
    deleteCardBtn = createDeleteCardButton();

    QHBoxLayout* upperPanelLt = new QHBoxLayout;
    upperPanelLt->addWidget(new QLabel(m_model->getCardPack()->id()));
    upperPanelLt->addWidget(deleteCardBtn);
    upperPanelLt->addWidget(editCardBtn);

    return upperPanelLt;
}

QToolButton* IStudyWindow::createEditCardButton()
{
    QToolButton* button = new QToolButton( this );
    button->setIcon( QIcon(":/images/pencil.png") );
    button->setIconSize( QSize(ToolBarIconSize, ToolBarIconSize) );
    button->setShortcut( tr("E", "Shortcut for 'Edit card' button") );
    button->setToolTip( tr("Edit card")+" ("+button->shortcut().toString()+")" );
    button->setFixedSize( ToolBarButtonSize, ToolBarButtonSize );
    connect( button, SIGNAL(clicked()), SLOT(openCardEditDialog()) );
    return button;
}

QToolButton* IStudyWindow::createDeleteCardButton()
{
    QToolButton* button = new QToolButton( this );
    button->setIcon( QIcon(":/images/red-cross.png") );
    button->setIconSize( QSize(ToolBarIconSize, ToolBarIconSize) );
    button->setShortcut( tr("D", "Shortcut for 'Delete card' button") );
    button->setToolTip( tr("Delete card")+" ("+button->shortcut().toString()+")" );
    button->setFixedSize( ToolBarButtonSize, ToolBarButtonSize );
    connect( button, SIGNAL(clicked()), SLOT(deleteCard()) );
    return button;
}

QVBoxLayout* IStudyWindow::createCardView()
{
    questionLabel = new CardSideView( CardSideView::QstMode );
    questionLabel->setPack( m_model->getCardPack() );

    answerStackedLt = new QStackedLayout;
    answerStackedLt->addWidget(createWrapper(createAnswerButtonLayout()));
    answerStackedLt->addWidget(createWrapper(createAnswerLayout()));
    answerStackedLt->setCurrentIndex(AnsButtonPage);

    QVBoxLayout* cardViewLt = new QVBoxLayout;
    cardViewLt->addWidget(questionLabel, 1);
    cardViewLt->addLayout(answerStackedLt, 1);

    return cardViewLt;
}

QBoxLayout* IStudyWindow::createAnswerButtonLayout()
{
    answerBtn = createAnswerButton();

    QBoxLayout* lt = new QVBoxLayout;
    lt->addStretch();
    if(getAnswerEdit())
        lt->addWidget(getAnswerEdit(), 0, Qt::AlignCenter);
    lt->addWidget(answerBtn, 0, Qt::AlignCenter);
    lt->addStretch();
    return lt;
}

QPushButton* IStudyWindow::createAnswerButton()
{
    QPushButton* button = new QPushButton(QIcon(":/images/info.png"), tr("Show answer"));
    button->setFixedSize(BigButtonWidth, BigButtonHeight);
    button->setShortcut(Qt::Key_Return);
    button->setToolTip(tr("Show answer") + ShortcutToStr(button) );
    connect(button, SIGNAL(clicked()), SLOT(showAnswer()));
    return button;
}

QBoxLayout* IStudyWindow::createAnswerLayout()
{
    answerLabel = new CardSideView( CardSideView::AnsMode );
    answerLabel->setPack( m_model->getCardPack() );

    QBoxLayout* lt = new QVBoxLayout;
    lt->setContentsMargins(QMargins());
    if(getUserAnswerLabel())
        lt->addWidget(getUserAnswerLabel(), 1);
    lt->addWidget(answerLabel, 1);
    return lt;
}

const DictTableView* IStudyWindow::cardEditView() const
    {
    if( m_cardEditDialog )
        return m_cardEditDialog->cardEditView();
    else
        return NULL;
    }

void IStudyWindow::openCardEditDialog()
    {
    if( m_cardEditDialog )  // already open
        return;
    Card* curCard = m_model->getCurCard();
    Q_ASSERT( curCard );
    MainWindow* mainWindow = dynamic_cast<MainWindow*>( m_parentWidget );
    if( !mainWindow )
        return;
    m_cardEditDialog = new CardEditDialog( curCard, mainWindow, this );
    m_cardEditDialog->exec();    
    delete m_cardEditDialog;
    m_cardEditDialog = NULL;
    Dictionary* dict = static_cast<Dictionary*>(m_model->getCardPack()->dictionary());
    dict->save();
    setWindowTitle(m_studyName + " - " + dict->shortName());
    }

void IStudyWindow::deleteCard()
    {
    QString question = m_model->getCurCard()->getQuestion();
    QMessageBox::StandardButton pressedButton;
    pressedButton = QMessageBox::question( this, tr("Delete card?"), tr("Delete card \"%1\"?").arg( question ),
        QMessageBox::Yes | QMessageBox::No, QMessageBox::Yes );
    if( pressedButton == QMessageBox::Yes )
        static_cast<Dictionary*>(m_model->getCardPack()->dictionary())->
            removeRecord( question );
    }

void IStudyWindow::showNextCard()
{
    Q_ASSERT( m_model );
    if( curCard )
        disconnect( curCard, 0, this, 0 );
    curCard = m_model->getCurCard();
    if( curCard )
        {
        connect( curCard, SIGNAL(answersChanged()), SLOT(updateCurCard()) );
        connect( curCard, SIGNAL(destroyed()), SLOT(invalidateCurCard()) );
        }
    setWindowTitle( m_studyName + " - " +
        static_cast<Dictionary*>(m_model->getCardPack()->dictionary())->shortName() );
    setStateForNextCard();
    processState();
}

void IStudyWindow::setStateForNextCard()
    {
    if( curCard )
        state = StateAnswerHidden;
    else
        state = StateNoCards;
    }

void IStudyWindow::showAnswer()
    {
    answerStackedLt->setCurrentIndex( AnsLabelPage );
    if( state == StateAnswerHidden )
        state = StateAnswerVisible;
    else
        return;
    processState();
    }

void IStudyWindow::updateCurCard()
{
    if( curCard )
        disconnect( curCard, 0, this, 0 );
    curCard = m_model->getCurCard();
    if( curCard )
        {
        connect( curCard, SIGNAL(answersChanged()), SLOT(updateCurCard()) );
        connect( curCard, SIGNAL(destroyed()), SLOT(invalidateCurCard()) );
        }
    setWindowTitle( m_studyName + " - " +
        static_cast<Dictionary*>(m_model->getCardPack()->dictionary())->shortName() );
    int origState = state;
    if( state == StateAnswerHidden || state == StateAnswerVisible )
        {
        state = StateAnswerHidden;
        processState();
        }
    if( origState == StateAnswerVisible )
        {
        state = StateAnswerVisible;
        processState();
        }
}

QString IStudyWindow::ShortcutToStr( QAbstractButton* aButton )
{
    return " (" + aButton->shortcut().toString( QKeySequence::NativeText ) + ")";
}

void IStudyWindow::updateToolBarVisibility(int index)
{
    bool visible = (index == CardPage);
    deleteCardBtn->setVisible(visible);
    editCardBtn->setVisible(visible);
}