qt5-legatus-legacy/Lts/Common/LtsUtils/LtsUtilsCore/pgarray.cpp

/**
  * Helper class for a vector of integer (stored as integer[] in the postgres database
  * $Id$
  * $HeadURL$
  * $Author$
  * Created by Christian Ehrlicher, SLSE, 2016-05-03
  */

#include "pgarray.h"
#include <QVector>
#include <QDebug>

#include <functional>
#include <LtsUtilsCore/ltsutilscore_export.h>

namespace LtsUtils
{

template<typename T>
static inline QString convertToPgString(const std::vector<T> &data)
{
  if (data.size() == 0)
    return QLatin1String("{}");
  QString ret(QLatin1Char('{'));
  for (T i : data)
    ret += QString::number(i) + QLatin1Char(',');
  ret.chop(1);
  ret += QLatin1Char('}');
  return ret;
}

template<>
LTSUTILSCORE_EXPORT QString IntArray::toPgString() const
{
  return convertToPgString(m_data);
}

template<>
LTSUTILSCORE_EXPORT QString BigintArray::toPgString() const
{
  return convertToPgString(m_data);
}

template<typename T>
static inline T convertFromPgString(const QString &str, const std::function<typename T::Type(const QStringRef &val, bool *bOk)> &convertFunc)
{
  typename T::ContainerType result;

  int idxStart = str.indexOf(QLatin1Char('{'));
  int idxEnd = str.lastIndexOf(QLatin1Char('}'));
  if (idxEnd < idxStart)
    return T(result);
  if (idxStart < 0 && idxEnd < 0)
  {
    // no {} around - fake midRef call
    idxStart = -1;
    idxEnd = str.length() + 1;
  }

  const QStringRef strRef = str.midRef(idxStart + 1, idxEnd - idxStart - 1);
  const QVector<QStringRef> vec = strRef.split(QLatin1Char(','), QString::SkipEmptyParts);
  result.reserve(vec.size());
  for (const QStringRef &s : vec)
  {
    bool ok = false;
    const typename T::Type i = convertFunc(s, &ok);
    if (ok)
      result.push_back(i);
  }

  return T(result);
}

template<>
LTSUTILSCORE_EXPORT IntArray IntArray::fromPgString(const QString &str)
{
  return convertFromPgString<IntArray>(str,
                                       [](const QStringRef & val, bool * bOk) { return val.toInt(bOk);});
}

template<>
LTSUTILSCORE_EXPORT BigintArray BigintArray::fromPgString(const QString &str)
{
  return convertFromPgString<BigintArray>(str,
                                          [](const QStringRef & val, bool * bOk) { return val.toLongLong(bOk);});
}


//
// 2D
//

template<typename T>
static inline QString convertToPgString(const std::map<T, T> &data)
{
  if (data.size() == 0)
    return QLatin1String("{}");
  QString ret(QLatin1Char('{'));
  for (const auto &it : data)
  {
    ret += QLatin1Char('{') + QString::number(it.first) +
           QLatin1Char(',') + QString::number(it.second) + QLatin1String("},");
  }
  ret.chop(1);
  ret += QLatin1Char('}');
  return ret;
}

template<>
LTSUTILSCORE_EXPORT QString IntArray2D::toPgString() const
{
  return convertToPgString<IntArray2D::Type>(m_data);
}

template<>
LTSUTILSCORE_EXPORT QString BigintArray2D::toPgString() const
{
  return convertToPgString<BigintArray2D::Type>(m_data);
}


template<typename T>
static inline T convertFromPgString2D(const QString &str, const std::function<typename T::Type(const QStringRef &val)> &convertFunc)
{
  typename T::ContainerType ret;
  int idxStart = str.indexOf(QLatin1Char('{'));
  int idxEnd = str.lastIndexOf(QLatin1Char('}'));
  if (idxEnd < idxStart)
    return T(ret);
  if (idxStart < 0 && idxEnd < 0)
  {
    // no {} around - fake midRef call
    idxStart = -1;
    idxEnd = str.length() + 1;
  }
  // remove first { and last } --> { 1, 2 }, { 4, 3 }, { 10, 1 }
  const QStringRef strRef = str.midRef(idxStart + 1, idxEnd - idxStart - 1);
  idxStart = strRef.indexOf(QLatin1Char('{'));
  while (idxStart >= 0)
  {
    idxEnd = strRef.indexOf(QLatin1Char('}'), idxStart);
    if (idxEnd < 0)
      break;
    // '{ 1, 2 }' -> ' 1, 2 '
    const QStringRef keyValueStr = strRef.mid(idxStart + 1, idxEnd - idxStart - 1);
    const QVector<QStringRef> keyValuePair = keyValueStr.split(QLatin1Char(','), QString::SkipEmptyParts);
    if (keyValuePair.size() != 2)
      break;
    const typename T::Type key = convertFunc(keyValuePair.at(0).trimmed());
    const typename T::Type value = convertFunc(keyValuePair.at(1).trimmed());
    ret.insert(std::make_pair(key, value));

    // search next
    idxStart = strRef.indexOf(QLatin1Char('{'), idxEnd + 1);
  }

  return T(ret);
}

template<>
LTSUTILSCORE_EXPORT IntArray2D IntArray2D::fromPgString(const QString &str)
{
  return convertFromPgString2D<IntArray2D>(str,
                                           [](const QStringRef & val) { return val.toInt();});
}

template<>
LTSUTILSCORE_EXPORT BigintArray2D BigintArray2D::fromPgString(const QString &str)
{
  return convertFromPgString2D<BigintArray2D>(str,
                                              [](const QStringRef & val) { return val.toLongLong();});
}

} // namespace LtsUtils