#include "tablemodel.h"

#include "../formats/jsonparser.h"
#include "commands/edititemcommand.h"
#include "commands/insertrowscommand.h"
#include "commands/removerowscommand.h"
#include "metadata.h"
#include "modelitem.h"

#include <QJsonArray>
#include <QJsonDocument>
#include <QJsonObject>

QByteArray TableModel::generateExampleItems() {
  QJsonDocument doc = QJsonDocument();
  QJsonObject rootObject;
  QJsonArray array;

  for (int row = 0; row < 5; ++row) {
    QJsonObject itemObject;
    //  itemObject.insert("uuid", m_uuid.toString());
    //  itemObject.insert("entryDateUTC", m_entryDateUTC.toString(Qt::ISODate));
    itemObject.insert(ROLE_NAMES.value(NameRole), QString("Item %1").arg(row));
    itemObject.insert(ROLE_NAMES.value(DescriptionRole), QString("This is item %1").arg(row));
    itemObject.insert(ROLE_NAMES.value(InfoRole), QString("Info of item %1").arg(row));
    itemObject.insert(ROLE_NAMES.value(AmountRole), row);
    itemObject.insert(ROLE_NAMES.value(FactorRole), row * 1.1);

    array.append(itemObject);
  }
  rootObject.insert("items", array);

  doc.setObject(rootObject);
  return doc.toJson();
}

TableModel::TableModel(QUndoStack* undoStack, QObject* parent)
    : QAbstractTableModel{parent}
    , m_undoStack(undoStack) {}

Qt::ItemFlags TableModel::flags(const QModelIndex& index) const {
  return Qt::ItemIsEditable | QAbstractTableModel::flags(index);
}

QHash<int, QByteArray> TableModel::roleNames() const { return ROLE_NAMES; }

int TableModel::rowCount(const QModelIndex& parent) const {
  Q_UNUSED(parent);
  return m_items.size();
}

int TableModel::columnCount(const QModelIndex& parent) const {
  Q_UNUSED(parent);
  return ROLE_NAMES.size();
}

QVariant TableModel::data(const QModelIndex& index, int role) const {
  const int row    = index.row();
  const int column = index.column();

  if (!index.isValid()) {
    return QVariant();
  }
  if (row >= rowCount(QModelIndex()) || column >= columnCount(QModelIndex())) {
    return QVariant();
  }

  int roleForColumn = getRoleForColumn(column);
  switch (role) {
    case Qt::DisplayRole:
    case Qt::EditRole:
      return m_items.at(row)->data(roleForColumn);
    case NameRole:
    case DescriptionRole:
    case InfoRole:
    case AmountRole:
    case FactorRole:
      return m_items.at(row)->data(role);
  }

  return QVariant();
}

QVariant TableModel::headerData(int section, Qt::Orientation orientation, int role) const {
  if (role == Qt::DisplayRole) {
    if (orientation == Qt::Horizontal) {
      const int columnRole     = getRoleForColumn(section);
      const QString headerName = ROLE_NAMES.value(columnRole);
      return QString("%1").arg(headerName);
    } else {
      return QString("%1").arg(section);
    }
  }
  return QVariant();
}

bool TableModel::setData(const QModelIndex& index, const QVariant& value, int role) {
  if (role == Qt::EditRole && checkIndex(index)) {
    const int column        = index.column();
    const int roleForColumn = getRoleForColumn(column);
    return setItemData(index, {{roleForColumn, value}});
  }
  return false;
}

bool TableModel::setItemData(const QModelIndex& index, const QMap<int, QVariant>& roles) {
  if (!checkIndex(index)) {
    return false;
  }
  // if (isRoleReadOnly(roleForColumn)) {
  //   return false;
  // }

  QMap<int, QVariant> changedValues = onlyChangedValues(index, roles);
  if (changedValues.size() > 0) {
    EditItemCommand* editCommand = new EditItemCommand(this, index, changedValues);
    m_undoStack->push(editCommand);
    return true;
  }
  return false;
}

QJsonDocument TableModel::getAllItemsAsJsonDoc() const {
  QJsonDocument doc = QJsonDocument();
  QJsonObject rootObject;
  QJsonArray array;

  foreach (shared_ptr<ModelItem> item, m_items) {
    QJsonObject itemObject = item->toJsonObject();
    array.append(itemObject);
  }
  rootObject.insert("items", array);

  doc.setObject(rootObject);
  return doc;
}

bool TableModel::removeRows(int firstRow, int nRows, const QModelIndex& parentIndex) {
  if (parentIndex != QModelIndex()) {
    qWarning() << "Removing of child rows is not supported yet!";
    return false;
  }

  const int lastRow = firstRow + nRows - 1;
  if (firstRow < 0 || lastRow >= m_items.size()) {
    qWarning() << "Trying to remove rows is out of bounds!";
    return false;
  }

  RemoveRowsCommand* removeCommand = new RemoveRowsCommand(this, firstRow, nRows);
  m_undoStack->push(removeCommand);

  return true;
}

void TableModel::appendItems(const QByteArray& jsonDoc) { insertItems(-1, jsonDoc, QModelIndex()); }

void TableModel::insertItems(int startPosition,
                             const QByteArray& jsonDoc,
                             const QModelIndex& parentIndex) {
  qInfo() << "Inserting item(s) into model...";
  if (parentIndex != QModelIndex()) {
    qWarning() << "Using invalid parent index (no child support for now)";
  }
  if (startPosition == -1 || startPosition > m_items.size()) {
    /// Appending item(s)
    startPosition = m_items.size();
  }

  QList<QHash<int, QVariant>> valueList = JsonParser::toItemValuesList(jsonDoc, "items");

  InsertRowsCommand* insertCommand = new InsertRowsCommand(this, startPosition, valueList);
  m_undoStack->push(insertCommand);
}

void TableModel::execInsertItems(const int firstRow, const QList<QHash<int, QVariant>> valueList) {
  const int nRows = valueList.size();
  qDebug() << "Inserting" << nRows << "items...";

  const int lastRow = firstRow + nRows - 1;
  beginInsertRows(QModelIndex(), firstRow, lastRow);
  for (int row = 0; row < nRows; ++row) {
    const int rowPosition      = firstRow + row;
    shared_ptr<ModelItem> item = make_unique<ModelItem>(valueList.at(row));
    m_items.insert(rowPosition, std::move(item));
  }
  endInsertRows();
}

void TableModel::execRemoveItems(const int firstRow, const int nRows) {
  const int lastRow = firstRow + nRows - 1;
  beginRemoveRows(QModelIndex(), firstRow, lastRow);
  m_items.remove(firstRow, nRows);
  endRemoveRows();
}

void TableModel::execEditItemData(const int row, const QMap<int, QVariant>& changedValues) {
  shared_ptr<ModelItem> item = m_items.at(row);
  bool isDataChanged         = item->setItemData(changedValues);

  if (isDataChanged) {
    /// FIXME due to the mapping from roles to the DisplayRole of different columns the complete row
    /// is getting notified about (potential) data changes; dataChanged should be called only for
    /// the affected columns
    const QModelIndex firstIndex = this->index(row, 0);
    const QModelIndex lastIndex  = this->index(row, ROLE_NAMES.size() - 1);
    QList<int> roles             = changedValues.keys();
    roles.insert(0, Qt::DisplayRole);
    emit dataChanged(firstIndex, lastIndex, roles.toVector());
  }
}

QMap<int, QVariant> TableModel::onlyChangedValues(const QModelIndex& index,
                                                  const QMap<int, QVariant>& roleValueMap) const {
  QMap<int, QVariant> result;
  QMap<int, QVariant>::const_iterator i;
  for (i = roleValueMap.constBegin(); i != roleValueMap.constEnd(); ++i) {
    const int role          = i.key();
    const QVariant newValue = i.value();
    const QVariant oldValue = index.data(role);
    // TODO check if role is a editable role?
    if (oldValue != newValue) {
      bool emptyValueIsEqualToZero = isEmptyValueEqualToZero(role);
      if (emptyValueIsEqualToZero && oldValue == QVariant() && newValue == 0) {
        qDebug() << "oldValue:" << oldValue << "& newValue:" << newValue
                 << "mean the same. Ignoring...";
        continue;
      }
      qDebug() << "oldValue:" << oldValue << "!= newValue:" << newValue;
      result.insert(role, newValue);
    } else {
      qInfo() << "oldValue is already the same as newValue:" << oldValue << "-> ignoring...";
    }
  }
  return result;
}

bool TableModel::isEmptyValueEqualToZero(const int role) const {
  const QString roleName = ROLE_NAMES.value(role);
  if (intColumns.contains(roleName)) {
    return true;
  }
  return false;
}