#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(QTableView* tableView, 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);

  qDebug() << "Setting model...";
  m_tableView      = tableView;
  m_model          = tableView->model();
  m_selectionModel = tableView->selectionModel();

  m_mapper->setModel(m_model);

  setupNavigationButtons();
  setupWidgets();

  setupConnections();
}

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) {
    clearEditWidgets();
  }

  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);
}

void ItemDetailMapper::setupConnections() {
  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());
}

void ItemDetailMapper::setupNavigationButtons() {
  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);
}

void ItemDetailMapper::setupWidgets() {
  m_layout = new QGridLayout();

  addWidgetsWithMapping(0);
  addWidgetsWithMapping(1);
  addWidgetsWithMapping(2);

  m_typeLabel = new QLabel(GET_HEADER_FOR_COLUMN(3));
  m_typeBox   = new QComboBox();
  m_typeLabel->setBuddy(m_typeBox);
  m_typeModel = new QStringListModel(TYPES, this);
  m_typeBox->setModel(m_typeModel);
  m_layout->addWidget(m_typeLabel, 3, 0);
  m_layout->addWidget(m_typeBox, 3, 1);
  m_mapper->addMapping(m_typeBox, 3, "currentText");

  m_amountLabel = new QLabel("&Amount");
  m_amountBox   = new QSpinBox();
  m_amountBox->setMaximum(1000);
  m_amountLabel->setBuddy(m_amountBox);
  m_layout->addWidget(m_amountLabel, 4, 0);
  m_layout->addWidget(m_amountBox, 4, 1);
  m_mapper->addMapping(m_amountBox, 4);

  m_factorLabel = new QLabel("&Factor");
  m_factorBox   = new QDoubleSpinBox();
  m_factorBox->setMaximum(1000);
  m_factorLabel->setBuddy(m_factorBox);
  m_layout->addWidget(m_factorLabel, 5, 0);
  m_layout->addWidget(m_factorBox, 5, 1);
  m_mapper->addMapping(m_factorBox, 5);

  const int nRows = m_layout->rowCount();
  m_layout->addWidget(m_previousButton, nRows, 0);
  m_layout->addWidget(m_nextButton, nRows, 1);

  setLayout(m_layout);
}

void ItemDetailMapper::addWidgetsWithMapping(const int column) {
  QPair<QWidget*, QWidget*> widgetPair0 = createWidgetPairForColumn(column);
  QWidget* control                      = widgetPair0.second;
  m_layout->addWidget(widgetPair0.first, column, 0);
  m_layout->addWidget(control, column, 1);
  m_mapper->addMapping(control, column);
  editControls.append(control);
}

QPair<QWidget*, QWidget*> ItemDetailMapper::createWidgetPairForColumn(const int column) {
  const UserRoles role = GET_ROLE_FOR_COLUMN(column);

  QWidget* edit;
  if (STRING_ROLES.contains(role)) {
    edit = new QLineEdit();
  } else {
    qCritical()
        << QString("Only string roles are supported yet. But tried with role %1!!!").arg(role);
    qDebug() << "Using line edit as well and pretend it's a string role...";
    edit = new QLineEdit();
  }

  const QString string = QString("&%1").arg(GET_HEADER_FOR_COLUMN(column));
  QLabel* label        = new QLabel(string);
  label->setBuddy(edit);
  return QPair<QWidget*, QWidget*>(label, edit);
}

void ItemDetailMapper::clearEditWidgets() {
  setEnabled(false);

  clearLineEdit(0);
  clearLineEdit(1);
  clearLineEdit(2);

  m_typeBox->setCurrentIndex(m_typeBox->count() - 1);
  m_amountBox->clear();
  m_factorBox->clear();
}

void ItemDetailMapper::clearLineEdit(const int column) {
  QLineEdit* lineEdit = dynamic_cast<QLineEdit*>(editControls[column]);
  if (lineEdit) {
    lineEdit->clear();
  }
}