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#pragma once
#include <database/engine.hpp>
#include <database/delete_query.hpp>
#include <database/row.hpp>
#include <algorithm>
#include <string>
#include <set>
using namespace std::string_literals;
template <typename T>
std::string ToSQLType(DatabaseEngine& db)
{
if (std::is_same<T, Id>::value)
return db.id_column_type();
else if (std::is_same<typename T::real_type, std::string>::value)
return "TEXT";
else
return "INTEGER";
}
template <typename ColumnType>
void add_column_to_table(DatabaseEngine& db, const std::string& table_name)
{
const std::string name = ColumnType::name;
std::string query{"ALTER TABLE " + table_name + " ADD " + ColumnType::name + " " + ToSQLType<ColumnType>(db)};
auto res = db.raw_exec(query);
if (std::get<0>(res) == false)
log_error("Error adding column ", name, " to table ", table_name, ": ", std::get<1>(res));
}
template <typename ColumnType, decltype(ColumnType::options) = nullptr>
void append_option(std::string& s)
{
s += " "s + ColumnType::options;
}
template <typename, typename... Args>
void append_option(Args&& ...)
{ }
template <typename... T>
class Table
{
static_assert(sizeof...(T) > 0, "Table cannot be empty");
using ColumnTypes = std::tuple<T...>;
public:
using RowType = Row<T...>;
Table(std::string name):
name(std::move(name))
{}
void upgrade(DatabaseEngine& db)
{
const auto existing_columns = db.get_all_columns_from_table(this->name);
add_column_if_not_exists(db, existing_columns);
}
void create(DatabaseEngine& db)
{
std::string query{"CREATE TABLE IF NOT EXISTS "};
query += this->name;
query += " (";
this->add_column_create(db, query);
query += ")";
auto result = db.raw_exec(query);
if (std::get<0>(result) == false)
log_error("Error executing query: ", std::get<1>(result));
}
RowType row()
{
return {this->name};
}
auto del()
{
DeleteQuery query(this->name);
return query;
}
const std::string& get_name() const
{
return this->name;
}
const std::string name;
private:
template <std::size_t N=0>
typename std::enable_if<N < sizeof...(T), void>::type
add_column_if_not_exists(DatabaseEngine& db, const std::set<std::string>& existing_columns)
{
using ColumnType = typename std::remove_reference<decltype(std::get<N>(std::declval<ColumnTypes>()))>::type;
if (existing_columns.count(ColumnType::name) == 0)
add_column_to_table<ColumnType>(db, this->name);
add_column_if_not_exists<N+1>(db, existing_columns);
}
template <std::size_t N=0>
typename std::enable_if<N == sizeof...(T), void>::type
add_column_if_not_exists(DatabaseEngine&, const std::set<std::string>&)
{}
template <std::size_t N=0>
typename std::enable_if<N < sizeof...(T), void>::type
add_column_create(DatabaseEngine& db, std::string& str)
{
using ColumnType = typename std::remove_reference<decltype(std::get<N>(std::declval<ColumnTypes>()))>::type;
str += ColumnType::name;
str += " ";
str += ToSQLType<ColumnType>(db);
if (N != sizeof...(T) - 1)
str += ",";
add_column_create<N+1>(db, str);
}
template <std::size_t N=0>
typename std::enable_if<N == sizeof...(T), void>::type
add_column_create(DatabaseEngine&, std::string&)
{ }
};
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