pgLab/pgsql/Pgsql_Value.h

130 lines
2.7 KiB
C++

#ifndef PGSQL_VALUE_H
#define PGSQL_VALUE_H
#include "Pgsql_declare.h"
#include "ArrayParser.h"
#include <sstream>
#include <QString>
#include <QDateTime>
namespace Pgsql {
/** \brief Class that is returned as value of a cell to facilitate auto conversion.
*/
class Value {
public:
Value(const char *val, Oid typ);
QString asQString() const;
const char* c_str() const { return m_val; }
operator QString() const;
operator QDateTime() const;
operator QDate() const;
operator QTime() const;
operator std::string() const;
operator int16_t() const;
operator int32_t() const;
operator Oid() const;
operator int64_t() const;
operator bool() const;
operator float() const;
operator double() const;
bool isString() const;
enum class NullHandling {
Ignore,
Throw
};
/**
*
* \param insert_iter An insert_iterator which is used to add the elements of the array to a container.
*/
template <typename E, typename I>
void getAsArray(I insert_iter, NullHandling nullhandling = NullHandling::Throw) const
{
using value_type = E;
ArrayParser parser(m_val);
for (;;) {
auto res = parser.GetNextElem();
if (res.ok) {
if (res.value) {
std::string str(res.value->data(), res.value->length());
Value val(str.c_str(), ANYOID);
value_type v;
v << val;
insert_iter = v;
}
else {
if (nullhandling == NullHandling::Throw)
throw std::runtime_error("Unexpected NULL value in array");
}
}
else
break;
}
}
template <typename E, typename I>
void getAsArray(I insert_iter, const E &value_for_nulls) const
{
using value_type = E;
ArrayParser parser(m_val);
for (;;) {
auto res = parser.GetNextElem();
if (res.ok) {
if (res.value) {
std::string str(res.value->data(), res.value->length());
Value val(str.c_str(), ANYOID);
value_type v;
v << val;
insert_iter = v;
}
else {
insert_iter = value_for_nulls;
}
}
else
break;
}
}
template <typename E, typename I>
void getAsArrayOfOptional(I insert_iter) const
{
using value_type = E;
ArrayParser parser(m_val);
for (;;) {
auto res = parser.GetNextElem();
if (res.ok) {
if (res.value) {
std::string str(res.value->data(), res.value->length());
Value val(str.c_str(), ANYOID);
value_type v;
v << val;
insert_iter = v;
}
else {
insert_iter = std::nullopt;
}
}
else
break;
}
}
private:
const char *m_val;
Oid m_typ;
};
template <typename T>
void operator<<(T &s, const Value &v)
{
s = static_cast<T>(v);
}
} // end namespace Pgsql
#endif // PGSQL_VALUE_H