#include "test.h"
#include <gtest/gtest.h>

#include <game/prng.h>

// From https://www.mscs.dal.ca/~selinger/random/, 2020-05-25
static const int NUM_RANDOM_INTEGERS = 60;
static const int GLIBC_SEED_1_RANDOM_INTEGERS[NUM_RANDOM_INTEGERS] = {
	1804289383, 846930886, 1681692777, 1714636915, 1957747793,
	424238335, 719885386, 1649760492, 596516649, 1189641421,
	1025202362, 1350490027, 783368690, 1102520059, 2044897763,
	1967513926, 1365180540, 1540383426, 304089172, 1303455736,
	35005211, 521595368, 294702567, 1726956429, 336465782,
	861021530, 278722862, 233665123, 2145174067, 468703135,
	1101513929, 1801979802, 1315634022, 635723058, 1369133069,
	1125898167, 1059961393, 2089018456, 628175011, 1656478042,
	1131176229, 1653377373, 859484421, 1914544919, 608413784,
	756898537, 1734575198, 1973594324, 149798315, 2038664370,
	1129566413, 184803526, 412776091, 1424268980, 1911759956,
	749241873, 137806862, 42999170, 982906996, 135497281,
};

TEST(Prng, EqualsGlibc)
{
	const int *EXPECTED = GLIBC_SEED_1_RANDOM_INTEGERS;

	CPrng Prng;
	Prng.Seed(1);
	for(int i = 0; i < NUM_RANDOM_INTEGERS; i++)
	{
		EXPECT_EQ(Prng.RandomInt(), EXPECTED[i]);
	}
}

TEST(Prng, Description)
{
	CPrng Prng;
	EXPECT_STREQ(Prng.Description(), "glibc-rand-emu:unseeded");

	Prng.Seed(0x01234567);
	EXPECT_STREQ(Prng.Description(), "glibc-rand-emu:01234567");
	Prng.Seed(0xfedbca98);
	EXPECT_STREQ(Prng.Description(), "glibc-rand-emu:fedbca98");
}