/***************************************************************************

    source::worx xtree
    Copyright © 2024-2025 c.holzheuer
    christoph.holzheuer@gmail.com

    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.

***************************************************************************/

#include <QApplication>
#include <QItemEditorFactory>
#include <QLineEdit>
#include <QComboBox>
#include <QDoubleSpinBox>
#include <QProgressBar>
#include <QSlider>

#include <QPainter>
#include <QHeaderView>
#include <QCommonStyle>

#include <xqitemdelegate.h>
#include <xqtreetable.h>
#include <xqitemtype.h>
#include <xqviewmodel.h>


//! erzeugt eine editorfactory mit den hauseigenen editortypen.

class XQItemEditorFactory : public QItemEditorFactory
{
public:

  XQItemEditorFactory()
  {
    registerEditor(XQItem::LineEditType,      new QStandardItemEditorCreator<QLineEdit>());
    registerEditor(XQItem::ComboBoxType,      new QStandardItemEditorCreator<QComboBox>());
    registerEditor(XQItem::PickerType,        new QStandardItemEditorCreator<QLineEdit>());
    //registerEditor(XQItem::ColorBarType,   new QStandardItemEditorCreator<QProgressBar>());
    registerEditor(XQItem::ColorBarType,   new QStandardItemEditorCreator<QSlider>());
    registerEditor(XQItem::SpinBoxType,       new QStandardItemEditorCreator<QSpinBox>());
    registerEditor(XQItem::CustomEditorType,  new QStandardItemEditorCreator<QLineEdit>());
  }

};


//! kontruktor mit dem zusändigen viewModel

XQItemDelegate::XQItemDelegate( XQViewModel& viewModel)
    : QStyledItemDelegate(), _modelView{viewModel}
{
  static  XQItemEditorFactory s_EditorFactory;
  setItemEditorFactory(&s_EditorFactory);
}


//! gibt die interne tree table zurück

XQTreeTable* XQItemDelegate::treeTable() const
{
  return _modelView.treeTable();
}


//! shortcut: gibt das XQItem für den gegebenen index zurück.

XQItem& XQItemDelegate::xqItemFromIndex( const QModelIndex& index ) const
{
  return _modelView.xqItemFromIndex( index );
}


//! überladene paint-methode: zeichnet das item je nach render-style.

void XQItemDelegate::paint(QPainter* painter, const QStyleOptionViewItem& option, const QModelIndex& index) const
{
  if( index.isValid() )
  {
    XQItem& item = xqItemFromIndex( index );
    switch( item.renderStyle()  )
    {
        case XQItem::HeaderStyle :
          return drawHeaderStyle( painter, option, item );
          //return drawHeaderStyleX( painter, option, index );

        case XQItem::ComboBoxStyle :
          return drawComboBoxStyle( painter, option, item );

        case XQItem::ColorBarStyle :
          return drawColorBarStyle( painter, option, item );

        // das funktioniert nicht unter windows11
        //case XQItem::SpinBoxStyle :
        // return drawSpinBoxStyle( painter, option, item );

        case XQItem::HiddenStyle :
          return;

        default:
          break;
    } // switch
  }
  else
  {
    qDebug() << " ---- paint: INDEX DEAD!"  ;
  }
  QStyledItemDelegate::paint(painter, option, index);

}


//! einen section header im header-style zeichnen

void XQItemDelegate::drawHeaderStyle(QPainter* painter, const QStyleOptionViewItem& option, const XQItem& item) const
{
  QStyleOptionHeader headerOption;

  // use the header as "parent" for style init
  QWidget* srcWidget = treeTable();//->header();
  headerOption.initFrom(srcWidget);
  headerOption.text = item.text();//index.data(Qt::DisplayRole).toString();
  headerOption.rect = option.rect;//.adjusted(0,0,0,3);
  headerOption.styleObject = option.styleObject;
  // __ch: reduce inner offset when painting
  headerOption.textAlignment |= Qt::AlignVCenter;
  headerOption.icon = item.icon();

  // save painter
  painter->save();
  //value = index.data(Qt::ForegroundRole);
  //if (value.canConvert<QBrush>())
  //headerOption.palette.setBrush(QPalette::Text, Qt::red );
  //headerOption.palette.setBrush(QPalette::Window, Qt::red );
  //QCommonStyle itemStyle;

  //qApp->style()->drawControl(QStyle::CE_Header, &headerOption, painter, srcWidget);
  //srcWidget->style()->drawControl(QStyle::CE_Header, &headerOption, painter, srcWidget);
  // warum das nur mit dem commonstyle, ist mir echt unklar.
  _commonStyle.drawControl(QStyle::CE_Header, &headerOption, painter, srcWidget);
  // restore painter
  painter->restore();


}


//! Zeichnet prozent-werte als balken

void XQItemDelegate::drawColorBarStyle(QPainter* painter, const QStyleOptionViewItem& option, const XQItem& item) const
{
  //QStyledItemDelegate::paint(painter, option, item);

  // Wert aus dem Modell holen
  bool ok;
  int value = item.data(Qt::EditRole).toInt(&ok);
  if (!ok || value < 0 || value > 100)
    return;

  // Balkenbereich berechnen
  QRect rect = option.rect.adjusted(2, 2, -2, -2); // etwas Padding
  int barWidth = static_cast<int>(rect.width() * (value / 100.0));

  // Balken zeichnen
  painter->save();
  painter->setRenderHint(QPainter::Antialiasing);

  QRect barRect(rect.left(), rect.top(), barWidth, rect.height());
  QColor barColor = QColor(100, 180, 255);
  painter->setBrush(barColor);
  painter->setPen(Qt::NoPen);
  painter->drawRect(barRect);

  painter->setPen(Qt::black);
  painter->drawText(rect, Qt::AlignCenter, item.text() );

  painter->restore();

}


//! Zeichnet das Item als combo box.

void XQItemDelegate::drawComboBoxStyle(QPainter* painter, const QStyleOptionViewItem& option, const XQItem& item) const
{
  QStyleOptionComboBox comboOption;

  QWidget* srcWidget = qobject_cast<QWidget*>(option.styleObject);
  comboOption.initFrom(srcWidget);

  // set options
  comboOption.rect = option.rect;
  comboOption.state = option.state | QStyle::State_Selected | QStyle::State_Enabled;
  // not editable => only visual, but painter needs to know it
  comboOption.editable = false;
  comboOption.currentText = item.text();
  // decoration (if any)
  comboOption.currentIcon = qvariant_cast<QIcon>(item.data(Qt::DecorationRole));
  comboOption.iconSize = comboOption.currentIcon.actualSize(QSize(option.rect.height() - 3, option.rect.height() - 3));

  // save painter
  painter->save();

  // hier wiederum funktioniert der '_commonStyle' nicht
  QStyle* widgetStyle = srcWidget->style();
  // draw combo
  widgetStyle->drawComplexControl(QStyle::CC_ComboBox, &comboOption, painter, srcWidget);
  // and combobox label
  widgetStyle->drawControl(QStyle::CE_ComboBoxLabel, &comboOption, painter, srcWidget);
  // restore painter
  painter->restore();
}


//! Zeichnet das Item als spin box.

void XQItemDelegate::drawSpinBoxStyle(QPainter* painter, const QStyleOptionViewItem& option, const XQItem& item) const
{

  qDebug() << " --- jawas +++? SPINBOX!";

  QWidget* srcWidget = qobject_cast<QWidget*>(option.styleObject);
  QStyleOptionViewItem viewOption(option);
  QStyleOptionSpinBox spinBoxOption;
  spinBoxOption.initFrom(srcWidget);

  initStyleOption(&viewOption, item.index());
  if (option.state & QStyle::State_HasFocus)
  {
    viewOption.state = viewOption.state ^ QStyle::State_HasFocus; // Fokus nicht auf dem Hintergrund malen
  }
  QApplication::style()->drawPrimitive(QStyle::PE_PanelItemViewItem, &viewOption, painter);

  spinBoxOption.rect = option.rect;//.adjusted( 0,0,-40,0);
  spinBoxOption.state = option.state | QStyle::State_Sunken; // Sunken-State für den "LineEdit"-Look
  spinBoxOption.buttonSymbols = QAbstractSpinBox::UpDownArrows;
  spinBoxOption.stepEnabled = QAbstractSpinBox::StepUpEnabled | QAbstractSpinBox::StepDownEnabled;
  spinBoxOption.frame = true;

  _commonStyle.drawComplexControl(QStyle::CC_SpinBox, &spinBoxOption, painter, nullptr);
  painter->drawText(spinBoxOption.rect, Qt::AlignCenter, item.text());

}


//! Überschreibt QStyledItemDelegate::sizeHint(option, index);

QSize XQItemDelegate::sizeHint(const QStyleOptionViewItem& option, const QModelIndex& index) const
{
  return QStyledItemDelegate::sizeHint(option, index);
}


//! Erzeugt ein editor-widget, sofern ein gültiger content-Ptr vorhanden und ein editor-Type gesetzt ist.

QWidget* XQItemDelegate::createEditor(QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const
{
  Q_UNUSED(option);

  XQItem& item  = xqItemFromIndex(index);
  XQItem::EditorType edType = item.editorType();
  if( edType == XQItem::NoEditorType )
  {
    qDebug() << "---- NO Content or NO EditorType";
    return nullptr;
  }
  qDebug() << "---- ed type:" << XQItem::fetchEditorTypeToString( edType ) << ": " << edType;

  QWidget* editor = itemEditorFactory()->createEditor(edType, parent);;
  //return QStyledItemDelegate::createEditor( parent, option, index );
  return editor;
}


//! Füttert einen editor mit den model-daten

void XQItemDelegate::setEditorData(QWidget* editor, const QModelIndex& index) const
{

  XQItem& item = xqItemFromIndex( index );
  XQItem::EditorType edType = item.editorType();
  if( edType == XQItem::NoEditorType )
    return;

  switch( edType )
  {
    case XQItemType::ComboBoxType :
    {
      QComboBox* comboBox = qobject_cast<QComboBox*>(editor);
      // wir erwarten hier ein gültiges model?
      comboBox->setModel( item.fixedChoices());
      comboBox->setCurrentText( item.data().toString() );
      comboBox->showPopup();
      return;
    }

    default:

      // wir benutzen hier die DisplayRole wenn der Inhalt schon formatiert ist.
      int role = item.renderStyle() == XQItem::FormattedStyle ? Qt::DisplayRole : Qt::EditRole;
      QVariant value = index.data(role);

      QByteArray userProp = editor->metaObject()->userProperty().name();
      if (!userProp.isEmpty())
      {
        if (!value.isValid())
          value = QVariant(editor->property(userProp).metaType());
        editor->setProperty(userProp, value);
      }

  }

}


//! Schreibt die daten aus dem editor ins model zurück

void XQItemDelegate::setModelData(QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const
{

  XQItem& item = xqItemFromIndex( index );

  switch( item.editorType()  )
  {
    case XQItem::ComboBoxType :
    {
      QComboBox* comboBox = qobject_cast<QComboBox*>(editor);
      item.setData( comboBox->currentText(), Qt::DisplayRole );
      return;
    }

    default:
      break;

  }

  QStyledItemDelegate::setModelData(editor, model, index);
}


//! Überschreibt QItemDelegate::updateEditorGeometry. Nicht implementiert.

void XQItemDelegate::updateEditorGeometry(QWidget* editor, const QStyleOptionViewItem& option, const QModelIndex& index) const
{
  //qDebug() << "  --- update Editor Geometry";
  QStyledItemDelegate::updateEditorGeometry(editor, option, index);
}