#include "itemdetailmapper.h"

#include <QAbstractItemModel>
#include <QDataWidgetMapper>
#include <QGridLayout>
#include <QJsonArray>
#include <QJsonObject>
#include <QLabel>
#include <QLineEdit>
#include <QPushButton>
#include <QSpinBox>
#include <QTableView>
#include "model/metadata.h"

ItemDetailMapper::ItemDetailMapper(QWidget* parent)
    : QWidget{parent} {
  /// model mapping
  m_mapper = std::make_unique<QDataWidgetMapper>(this);
  /// BUG: If multiple columns are changed not all changes are applied.
  ///     Multiple changes are set individually by calling setData().
  ///     Probably due to a conflicting dataChanged signal for too many roles&columns the data of
  ///     the remaining columns is reset before setData is called.
  ///     And a manual submit would also create multiple undo steps anyway.
  /// Workaround: ManualSubmit -> AutoSubmit
  // m_mapper->setSubmitPolicy(QDataWidgetMapper::ManualSubmit);
  m_mapper->setSubmitPolicy(QDataWidgetMapper::AutoSubmit);

  /// model mapping buttons
  m_nextButton     = new QPushButton(tr("Ne&xt"));
  m_previousButton = new QPushButton(tr("&Previous"));

  connect(m_previousButton, &QAbstractButton::clicked, this, &ItemDetailMapper::toPrevious);
  connect(m_nextButton, &QAbstractButton::clicked, this, &ItemDetailMapper::toNext);

  /// the individual widgets
  // REFACTOR deduce label names and types from meta data & use a factory
  m_nameLabel = new QLabel("&Name");
  m_nameEdit  = new QLineEdit();
  m_nameLabel->setBuddy(m_nameEdit);

  m_descriptionLabel = new QLabel("&Description");
  m_descriptionEdit  = new QLineEdit();
  m_descriptionLabel->setBuddy(m_descriptionEdit);

  m_infoLabel = new QLabel("&Info");
  m_infoEdit  = new QLineEdit();
  m_infoLabel->setBuddy(m_infoEdit);

  m_amountLabel = new QLabel("&Amount");
  m_amountBox   = new QSpinBox();
  m_amountBox->setMaximum(1000);
  m_amountLabel->setBuddy(m_amountBox);

  m_factorLabel = new QLabel("&Factor");
  m_factorBox   = new QDoubleSpinBox();
  m_factorBox->setMaximum(1000);
  m_factorLabel->setBuddy(m_factorBox);

  QGridLayout* layout = new QGridLayout();
  layout->addWidget(m_nameLabel, 0, 0, 1, 1);
  layout->addWidget(m_nameEdit, 0, 1, 1, 1);
  layout->addWidget(m_descriptionLabel, 1, 0, 1, 1);
  layout->addWidget(m_descriptionEdit, 1, 1, 1, 1);
  layout->addWidget(m_infoLabel, 2, 0, 1, 1);
  layout->addWidget(m_infoEdit, 2, 1, 1, 1);
  layout->addWidget(m_amountLabel, 3, 0, 1, 1);
  layout->addWidget(m_amountBox, 3, 1, 1, 1);
  layout->addWidget(m_factorLabel, 4, 0, 1, 1);
  layout->addWidget(m_factorBox, 4, 1, 1, 1);

  layout->addWidget(m_previousButton, 5, 0, 1, 1);
  layout->addWidget(m_nextButton, 5, 1, 1, 1);

  setLayout(layout);
}

void ItemDetailMapper::setModelMappings(QTableView* tableView) {
  qDebug() << "Setting model...";
  m_tableView      = tableView;
  m_model          = tableView->model();
  m_selectionModel = tableView->selectionModel();

  m_mapper->setModel(m_model);
  m_mapper->addMapping(m_nameEdit, 0);
  m_mapper->addMapping(m_descriptionEdit, 1);
  m_mapper->addMapping(m_infoEdit, 2);
  m_mapper->addMapping(m_amountBox, 3);
  m_mapper->addMapping(m_factorBox, 4);

  m_mapper->setCurrentIndex(m_selectionModel->currentIndex().row());

  connect(m_model, &QAbstractItemModel::rowsInserted, this, &ItemDetailMapper::rowsInserted);
  connect(m_model, &QAbstractItemModel::rowsRemoved, this, &ItemDetailMapper::rowsRemoved);
  connect(m_selectionModel, &QItemSelectionModel::currentChanged, this,
          &ItemDetailMapper::onCurrentIndexChanged);

  updateButtons(m_selectionModel->currentIndex().row());
}

bool ItemDetailMapper::submit() { return m_mapper->submit(); }

void ItemDetailMapper::revert() { m_mapper->revert(); }

void ItemDetailMapper::onCurrentIndexChanged(const QModelIndex& current,
                                             const QModelIndex& /*previous*/) {
  if (!isEnabled()) {
    setEnabled(true);
  }
  m_mapper->setCurrentModelIndex(current);
  updateButtons(current.row());
  emitContentChanged(current);
}

void ItemDetailMapper::rowsInserted(const QModelIndex& parent, int start, int end) {
  updateButtons(m_mapper->currentIndex());
}

void ItemDetailMapper::rowsRemoved(const QModelIndex& parent, int start, int end) {
  if (m_model->rowCount() == 0) {
    setEnabled(false);

    m_nameEdit->clear();
    m_descriptionEdit->clear();
    m_infoEdit->clear();
    m_amountBox->clear();
    m_factorBox->clear();
  }

  updateButtons(m_mapper->currentIndex());
}

void ItemDetailMapper::toPrevious() {
  int currentRow            = m_selectionModel->currentIndex().row();
  QModelIndex previousIndex = m_selectionModel->currentIndex().siblingAtRow(currentRow - 1);
  if (previousIndex.isValid()) {
    m_selectionModel->setCurrentIndex(previousIndex, QItemSelectionModel::ClearAndSelect);
  }
}

void ItemDetailMapper::toNext() {
  int currentRow        = m_selectionModel->currentIndex().row();
  QModelIndex nextIndex = m_selectionModel->currentIndex().siblingAtRow(currentRow + 1);
  if (nextIndex.isValid()) {
    m_selectionModel->setCurrentIndex(nextIndex, QItemSelectionModel::ClearAndSelect);
  }
}

void ItemDetailMapper::updateButtons(int row) {
  m_previousButton->setEnabled(row > 0);
  m_nextButton->setEnabled(row < m_model->rowCount() - 1);
}

void ItemDetailMapper::emitContentChanged(const QModelIndex& currentIndex) {
  // BUG QR-Code isn't updated after changes through the ItemDetailMapper #18
  QString toStringText = "";
  if (currentIndex.isValid()) {
    toStringText = currentIndex.data(ToStringRole).toString();
  }
  emit contentChanged(toStringText);
}