#include <iostream>

#include <cstdlib>

#include <cmath>

#include <sqlite_modern_cpp.h>

#include <catch2/catch.hpp>

using namespace sqlite;

using namespace std;

int add_integers(int i, int j) {

return i+j;

}

TEST_CASE("sql functions work", "[functions]") {

database db(":memory:");

db.define("my_new_concat", [](std::string i, std::string j) {return i+j;});

db.define("my_new_concat", [](std::string i, std::string j, std::string k) {return i+j+k;});

db.define("add_integers", &add_integers);

std::string test1, test3;

int test2 = 0;

db << "select my_new_concat('Hello ','world!')" >> test1;

db << "select add_integers(1,1)" >> test2;

db << "select my_new_concat('a','b','c')" >> test3;

REQUIRE(test1 == "Hello world!");

REQUIRE(test2 == 2);

REQUIRE(test3 == "abc");

db.define("my_count", [](int &i, int) {++i;}, [](int &i) {return i;});

db.define("my_concat_aggregate", [](std::string &stored, std::string current) {stored += current;}, [](std::string &stored) {return stored;});

db << "create table countable(i, s)";

db << "insert into countable values(1, 'a')";

db << "insert into countable values(2, 'b')";

db << "insert into countable values(3, 'c')";

db << "select my_count(i) from countable" >> test2;

db << "select my_concat_aggregate(s) from countable order by i" >> test3;

REQUIRE(test2 == 3);

REQUIRE(test3 == "abc");

db.define("tgamma", [](double i) {return std::tgamma(i);});

db << "CREATE TABLE numbers (number INTEGER);";

for(auto i=0; i!=10; ++i)

db << "INSERT INTO numbers VALUES (?);" << i;

db << "SELECT number, tgamma(number+1) FROM numbers;" >> [](double number, double factorial) {

/* cout << number << "! = " << factorial << '\n'; */

};

}