module math_tests;
import std::math;

fn void! test_abs() @test
{
	int x = -21;
	assert(math::abs(x) == 21);
	double y = -123.0;
	assert(math::abs(y) == 123.0);
	float z = -21.0f;
	assert(math::abs(z) == 21.0f);
	$assert @typeis(math::abs(z), float);
	int[<3>] xx = { -1, -1000, 1000 };
	assert(math::abs(xx) == int[<3>] { 1, 1000, 1000 });
	double[<3>] yy = { -1, -0.5, 1000 };
	assert(math::abs(yy) == double[<3>] { 1, 0.5, 1000 });
}

fn void! test_atan() @test
{
	int x = 231;
	assert(math::atan(x) == 1.5664673495078372);
	x = 1;
	assert(math::atan(x) == 0.7853981633974483);
	x = 0;
	assert(math::atan(x) == 0.0);
	x = -1;
	assert(math::atan(x) == -0.7853981633974483);
	x = -231;
	assert(math::atan(x) == -1.5664673495078372);
	float f = 0;
	assert(math::atan(f) == 0.0f);
	f = 1;
	assert(math::atan(f) == 0.7853981633974483f);
	f = -1;
	assert(math::atan(f) == -0.7853981633974483f);
	assert(@typeis(math::atan(f), float));
	double d = 0;
	assert(math::atan(d) == 0.0);
	d = 1;
	assert(math::atan(d) == 0.7853981633974483);
	d = -1;
	assert(math::atan(d) == -0.7853981633974483);
	assert(@typeis(math::atan(d), double));
}

fn void! test_ceil() @test
{
	double d = -123.1;
	assert(math::ceil(d) == -123.0);
	d = 123.1;
	assert(math::ceil(d) == 124.0);
	d = 0.1;
	assert(math::ceil(d) == 1);
	d = -0.9;
	assert(math::ceil(d) == 0);
	$assert @typeis(math::ceil(d), double);
	float f = -123.1f;
	assert(math::ceil(f) == -123.0f);
	f = 123.1f;
	assert(math::ceil(f) == 124.0f);
	f = 0.1f;
	assert(math::ceil(f) == 1.0f);
	f = -0.9f;
	assert(math::ceil(f) == 0.0f);
	$assert @typeis(math::ceil(f), float);
	double[<5>] vec = { -123.1, 123.1, 0.1, -0.9, 0 };
	assert(math::ceil(vec) == double[<5>] { -123, 124, 1, 0, 0 });
}

fn void! test_floor() @test
{
	double d = -123.1;
	assert(math::floor(d) == -124.0);
	d = 123.1;
	assert(math::floor(d) == 123.0);
	d = 0.9;
	assert(math::floor(d) == 0);
	d = -0.1;
	assert(math::floor(d) == -1);
	$assert @typeis(math::floor(d), double);
	float f = -123.1f;
	assert(math::floor(f) == -124.0f);
	f = 123.1f;
	assert(math::floor(f) == 123.0f);
	f = 0.9f;
	assert(math::floor(f) == 0.0f);
	f = -0.1f;
	assert(math::floor(f) == -1.0f);
	$assert @typeis(math::floor(f), float);
	double[<5>] vec = { -123.1, 123.1, 0.9, -0.1, 0 };
	assert(math::floor(vec) == double[<5>] { -124, 123, 0, -1, 0 });
}

fn void! test_log() @test
{
	double x = math::E;
	assert(math::log(x, x) == 1.0);
	float y = math::E;
	assert(math::log(y, y) == 1.0f);
	$assert @typeis(math::log(y, y), float);
	double[<3>] xx = { 2, 4, 8 };
	assert(math::log(xx, 2) == double[<3>] { 1.0, 2.0, 3.0 });
	float[<3>] yy = { 10, 100, 1000 };
	assert(math::log(yy, 10) == float[<3>] { 1.0, 2.0, 3.0 });
}

fn void! test_sign() @test
{
	int x = -21;
	assert(math::sign(x) == -1);
	x = 238219382;
	assert(math::sign(x) == 1);
	x = 0;
	assert(math::sign(x) == 0);
	uint y = 23;
	assert(math::sign(y) == 1);
	y = 0;
	assert(math::sign(y) == 0);
	y = (uint)-21;
	assert(math::sign(y) == 1);
	assert(@typeis(math::sign(y), uint));
}

fn void! test_trunc() @test
{
	double d = -123.9;
	assert(math::trunc(d) == -123.0);
	d = 123.1;
	assert(math::trunc(d) == 123.0);
	d = 0.9;
	assert(math::trunc(d) == 0);
	d = -0.9;
	assert(math::trunc(d) == 0);
	$assert @typeis(math::trunc(d), double);
	float f = -123.9f;
	assert(math::trunc(f) == -123.0f);
	f = 123.9f;
	assert(math::trunc(f) == 123.0f);
	f = 0.9f;
	assert(math::trunc(f) == 0.0f);
	f = -0.9f;
	assert(math::trunc(f) == -0.0f);
	$assert @typeis(math::trunc(f), float);
	double[<5>] vec = { -123.9, 123.9, 0.9, -0.9, 0 };
	assert(math::trunc(vec) == double[<5>] { -123, 123, 0, 0, 0 });
}

fn void! test_round_decimals() @test
{
	double d = 0.532451241142;
	float d_f = 0.532451241142;
	assert(math::round_to_decimals(d, 2) == 0.53);
	assert(math::round_to_decimals(d, 5) == 0.53245);

	assert(math::round_to_decimals(d_f, 2) == 0.53f);
	assert(math::round_to_decimals(d_f, 5) == 0.53245f);
}

fn void! test() @test
{
	double radians = math::deg_to_rad(45);
	float radians_f = (float)math::deg_to_rad(45);

	assert(math::round_to_decimals(radians, 3) == 0.785);
	assert(math::round_to_decimals(radians_f, 3) == 0.785f);
}

fn void! test_muldiv()
{
	char a = 20;
	assert(a.muldiv(20, 10) == 40);
	ichar b = 20;
	assert(b.muldiv(20, -10) == -40);
	short c = 16000;
	assert(c.muldiv(4, 2) == 32000);
	ushort d = 16000;
	assert(d.muldiv(8, 2) == 64000);
	int e = 1_000_000;
	assert(e.muldiv(40000, 10000) == 4_000_000);
	uint f = 3_000_000_000u;
	assert(f.muldiv(110, 100) == 3_300_000_000u);
	long g = 1_000_000_000_000i64;
	assert(g.muldiv(2_000_000_000_000i64, 1_000_000_000i64) == 2_000_000_000_000_000i64);
	ulong h = 1_000_000_000_000u64;
	assert(h.muldiv(2_000_000_000_000u64, 1_000_000_000u64) == 2_000_000_000_000_000u64);

	char[<4>] i = {20, 30, 40, 50};
	assert(i.muldiv(12,10) == char[<4>] {24, 36, 48, 60});
	assert(i.muldiv(char[<4>]{11, 12, 13, 14}, char[<4>]{10,10,10,10}) == char[<4>]{22, 36, 52, 70});

	long[<4>] j = {1_000_000_000_000i64, 2_000_000_000_000i64, 3_000_000_000_000i64, 4_000_000_000_000i64};
	assert(j.muldiv(2_000_000_000_000i64, 1_000_000_000i64) == long[<4>]{2_000_000_000_000_000i64, 4_000_000_000_000_000i64, 6_000_000_000_000_000i64, 8_000_000_000_000_000i64});
	
	ichar[<4>] k = {20, 30, 40, 50};
	assert(k.muldiv(20,-10) == ichar[<4>]{-40,-60,-80,-100});
}

fn void! test_gcd() @test
{
	assert(math::gcd(20,15) == 5);
	assert(math::gcd(15,20) == 5);
	assert(math::gcd(-15,20) == 5);
	assert(math::gcd(15,-20) == 5);
	assert(math::gcd(-15,-20) == 5);
	assert(math::gcd(5,15,20) == 5);
	assert(math::gcd(1,2,3) == 1);
	assert(math::gcd(2,4,6,8) == 2);
}

fn void! test_lcm() @test
{
	assert(math::lcm(4,5) == 20);
	assert(math::lcm(6,10) == 30);
	assert(math::lcm(-8,20) == 40);
	assert(math::lcm(8,-20) == 40);
	assert(math::lcm(-8,-20) == 40);
	assert(math::lcm(11,17) == 11*17);
	assert(math::lcm(11,17,227,263) == 11*17*227*263);
}