#include "util.hpp"

#include <limits>
#include <stdexcept>
#include <type_traits>
#include <utility>

#include <QCheckBox>
#include <QItemEditorFactory>
#include <QLineEdit>
#include <QPlainTextEdit>
#include <QStyledItemDelegate>
#include <QUndoStack>

#include <apps/opencs/model/doc/document.hpp>
#include <apps/opencs/model/world/columnbase.hpp>
#include <apps/opencs/view/world/scripthighlighter.hpp>

#include "../../model/world/commanddispatcher.hpp"

#include "../widget/coloreditor.hpp"
#include "../widget/droplineedit.hpp"

#include "dialoguespinbox.hpp"
#include "scriptedit.hpp"

CSVWorld::NastyTableModelHack::NastyTableModelHack(QAbstractItemModel& model)
    : mModel(model)
{
}

int CSVWorld::NastyTableModelHack::rowCount(const QModelIndex& parent) const
{
    return mModel.rowCount(parent);
}

int CSVWorld::NastyTableModelHack::columnCount(const QModelIndex& parent) const
{
    return mModel.columnCount(parent);
}

QVariant CSVWorld::NastyTableModelHack::data(const QModelIndex& index, int role) const
{
    return mModel.data(index, role);
}

bool CSVWorld::NastyTableModelHack::setData(const QModelIndex& index, const QVariant& value, int role)
{
    mData = value;
    return true;
}

QVariant CSVWorld::NastyTableModelHack::getData() const
{
    return mData;
}

CSVWorld::CommandDelegateFactoryCollection* CSVWorld::CommandDelegateFactoryCollection::sThis = nullptr;

CSVWorld::CommandDelegateFactoryCollection::CommandDelegateFactoryCollection()
{
    if (sThis)
        throw std::logic_error("multiple instances of CSVWorld::CommandDelegateFactoryCollection");

    sThis = this;
}

CSVWorld::CommandDelegateFactoryCollection::~CommandDelegateFactoryCollection()
{
    sThis = nullptr;

    for (std::map<CSMWorld::ColumnBase::Display, CommandDelegateFactory*>::iterator iter(mFactories.begin());
         iter != mFactories.end(); ++iter)
        delete iter->second;
}

void CSVWorld::CommandDelegateFactoryCollection::add(
    CSMWorld::ColumnBase::Display display, CommandDelegateFactory* factory)
{
    mFactories.insert(std::make_pair(display, factory));
}

CSVWorld::CommandDelegate* CSVWorld::CommandDelegateFactoryCollection::makeDelegate(
    CSMWorld::ColumnBase::Display display, CSMWorld::CommandDispatcher* dispatcher, CSMDoc::Document& document,
    QObject* parent) const
{
    std::map<CSMWorld::ColumnBase::Display, CommandDelegateFactory*>::const_iterator iter = mFactories.find(display);

    if (iter != mFactories.end())
        return iter->second->makeDelegate(dispatcher, document, parent);

    return new CommandDelegate(dispatcher, document, parent);
}

const CSVWorld::CommandDelegateFactoryCollection& CSVWorld::CommandDelegateFactoryCollection::get()
{
    if (!sThis)
        throw std::logic_error("no instance of CSVWorld::CommandDelegateFactoryCollection");

    return *sThis;
}

QUndoStack& CSVWorld::CommandDelegate::getUndoStack() const
{
    return mDocument.getUndoStack();
}

CSMDoc::Document& CSVWorld::CommandDelegate::getDocument() const
{
    return mDocument;
}

CSMWorld::ColumnBase::Display CSVWorld::CommandDelegate::getDisplayTypeFromIndex(const QModelIndex& index) const
{
    int rawDisplay = index.data(CSMWorld::ColumnBase::Role_Display).toInt();
    return static_cast<CSMWorld::ColumnBase::Display>(rawDisplay);
}

void CSVWorld::CommandDelegate::setModelDataImp(
    QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const
{
    if (!mCommandDispatcher)
        return;

    QVariant variant;

    // Color columns use a custom editor, so we need to fetch selected color from it.
    CSVWidget::ColorEditor* colorEditor = qobject_cast<CSVWidget::ColorEditor*>(editor);
    if (colorEditor != nullptr)
    {
        variant = colorEditor->colorInt();
    }
    else
    {
        NastyTableModelHack hack(*model);
        QStyledItemDelegate::setModelData(editor, &hack, index);
        variant = hack.getData();
    }

    if ((model->data(index) != variant) && (model->flags(index) & Qt::ItemIsEditable))
        mCommandDispatcher->executeModify(model, index, variant);
}

CSVWorld::CommandDelegate::CommandDelegate(
    CSMWorld::CommandDispatcher* commandDispatcher, CSMDoc::Document& document, QObject* parent)
    : QStyledItemDelegate(parent)
    , mEditLock(false)
    , mCommandDispatcher(commandDispatcher)
    , mDocument(document)
{
}

void CSVWorld::CommandDelegate::setModelData(QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const
{
    if (!mEditLock)
    {
        setModelDataImp(editor, model, index);
    }

    ///< \todo provide some kind of feedback to the user, indicating that editing is currently not possible.
}

QWidget* CSVWorld::CommandDelegate::createEditor(
    QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const
{
    CSMWorld::ColumnBase::Display display = getDisplayTypeFromIndex(index);

    // This createEditor() method is called implicitly from tables.
    // For boolean values in tables use the default editor (combobox).
    // Checkboxes is looking ugly in the table view.
    // TODO: Find a better solution?
    if (display == CSMWorld::ColumnBase::Display_Boolean)
    {
        return QItemEditorFactory::defaultFactory()->createEditor(QVariant::Bool, parent);
    }
    // For tables the pop-up of the color editor should appear immediately after the editor creation
    // (the third parameter of ColorEditor's constructor)
    else if (display == CSMWorld::ColumnBase::Display_Colour)
    {
        return new CSVWidget::ColorEditor(index.data().toInt(), parent, true);
    }
    return createEditor(parent, option, index, display);
}

QWidget* CSVWorld::CommandDelegate::createEditor(QWidget* parent, const QStyleOptionViewItem& option,
    const QModelIndex& index, CSMWorld::ColumnBase::Display display) const
{
    QVariant variant = index.data();
    if (!variant.isValid())
    {
        variant = index.data(Qt::DisplayRole);
        if (!variant.isValid())
        {
            return nullptr;
        }
    }

    // NOTE: for each editor type (e.g. QLineEdit) there needs to be a corresponding
    // entry in CSVWorld::DialogueDelegateDispatcher::makeEditor()
    switch (display)
    {
        case CSMWorld::ColumnBase::Display_Colour:
        {
            return new CSVWidget::ColorEditor(variant.toInt(), parent);
        }
        case CSMWorld::ColumnBase::Display_Integer:
        {
            DialogueSpinBox* sb = new DialogueSpinBox(parent);
            sb->setRange(std::numeric_limits<int>::min(), std::numeric_limits<int>::max());
            return sb;
        }

        case CSMWorld::ColumnBase::Display_SignedInteger8:
        {
            DialogueSpinBox* sb = new DialogueSpinBox(parent);
            sb->setRange(std::numeric_limits<signed char>::min(), std::numeric_limits<signed char>::max());
            return sb;
        }
        case CSMWorld::ColumnBase::Display_SignedInteger16:
        {
            DialogueSpinBox* sb = new DialogueSpinBox(parent);
            sb->setRange(std::numeric_limits<short>::min(), std::numeric_limits<short>::max());
            return sb;
        }

        case CSMWorld::ColumnBase::Display_UnsignedInteger8:
        {
            DialogueSpinBox* sb = new DialogueSpinBox(parent);
            sb->setRange(0, std::numeric_limits<unsigned char>::max());
            return sb;
        }

        case CSMWorld::ColumnBase::Display_UnsignedInteger16:
        {
            DialogueSpinBox* sb = new DialogueSpinBox(parent);
            sb->setRange(0, std::numeric_limits<unsigned short>::max());
            return sb;
        }

        case CSMWorld::ColumnBase::Display_Var:

            return new QLineEdit(parent);

        case CSMWorld::ColumnBase::Display_Float:
        {
            DialogueDoubleSpinBox* dsb = new DialogueDoubleSpinBox(parent);
            dsb->setRange(-std::numeric_limits<float>::max(), std::numeric_limits<float>::max());
            dsb->setSingleStep(0.01f);
            dsb->setDecimals(3);
            return dsb;
        }

        case CSMWorld::ColumnBase::Display_Double:
        {
            DialogueDoubleSpinBox* dsb = new DialogueDoubleSpinBox(parent);
            dsb->setRange(-std::numeric_limits<double>::max(), std::numeric_limits<double>::max());
            dsb->setSingleStep(0.01f);
            dsb->setDecimals(6);
            return dsb;
        }

        /// \todo implement size limit. QPlainTextEdit does not support a size limit.
        case CSMWorld::ColumnBase::Display_LongString:
        case CSMWorld::ColumnBase::Display_LongString256:
        {
            QPlainTextEdit* edit = new QPlainTextEdit(parent);
            edit->setUndoRedoEnabled(false);
            return edit;
        }

        case CSMWorld::ColumnBase::Display_Boolean:

            return new QCheckBox(parent);

        case CSMWorld::ColumnBase::Display_ScriptLines:

            return new ScriptEdit(mDocument, ScriptHighlighter::Mode_Console, parent);

        case CSMWorld::ColumnBase::Display_String:
            // For other Display types (that represent record IDs) with drop support IdCompletionDelegate is used

            return new CSVWidget::DropLineEdit(display, parent);

        case CSMWorld::ColumnBase::Display_String32:
        {
            // For other Display types (that represent record IDs) with drop support IdCompletionDelegate is used
            CSVWidget::DropLineEdit* widget = new CSVWidget::DropLineEdit(display, parent);
            widget->setMaxLength(32);
            return widget;
        }

        case CSMWorld::ColumnBase::Display_String64:
        {
            // For other Display types (that represent record IDs) with drop support IdCompletionDelegate is used
            CSVWidget::DropLineEdit* widget = new CSVWidget::DropLineEdit(display, parent);
            widget->setMaxLength(64);
            return widget;
        }

        default:

            return QStyledItemDelegate::createEditor(parent, option, index);
    }
}

void CSVWorld::CommandDelegate::setEditLock(bool locked)
{
    mEditLock = locked;
}

bool CSVWorld::CommandDelegate::isEditLocked() const
{
    return mEditLock;
}

void CSVWorld::CommandDelegate::setEditorData(QWidget* editor, const QModelIndex& index) const
{
    setEditorData(editor, index, false);
}

void CSVWorld::CommandDelegate::setEditorData(QWidget* editor, const QModelIndex& index, bool tryDisplay) const
{
    QVariant variant = index.data(Qt::EditRole);
    if (tryDisplay)
    {
        if (!variant.isValid())
        {
            variant = index.data(Qt::DisplayRole);
            if (!variant.isValid())
            {
                return;
            }
        }
        QPlainTextEdit* plainTextEdit = qobject_cast<QPlainTextEdit*>(editor);
        if (plainTextEdit) // for some reason it is easier to brake the loop here
        {
            if (plainTextEdit->toPlainText() == variant.toString())
            {
                return;
            }
        }
    }

    // Color columns use a custom editor, so we need explicitly set a data for it
    CSVWidget::ColorEditor* colorEditor = qobject_cast<CSVWidget::ColorEditor*>(editor);
    if (colorEditor != nullptr)
    {
        colorEditor->setColor(variant.toInt());
        return;
    }

    QByteArray n = editor->metaObject()->userProperty().name();

    if (n == "dateTime")
    {
        if (editor->inherits("QTimeEdit"))
            n = "time";
        else if (editor->inherits("QDateEdit"))
            n = "date";
    }

    if (!n.isEmpty())
    {
        if (!variant.isValid())
#if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
            variant = QVariant(editor->property(n).metaType(), (const void*)nullptr);
#else
            variant = QVariant(editor->property(n).userType(), (const void*)nullptr);
#endif
        editor->setProperty(n, variant);
    }
}

void CSVWorld::CommandDelegate::settingChanged(const CSMPrefs::Setting* setting) {}
