#include <uf/utils/noise/noise.h>

uf::PerlinNoise::PerlinNoise() {
	this->m_permutations = {
		151,160,137,91,90,15,131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,
		8,99,37,240,21,10,23,190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,
		35,11,32,57,177,33,88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,
		134,139,48,27,166,77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,
		55,46,245,40,244,102,143,54, 65,25,63,161,1,216,80,73,209,76,132,187,208, 89,
		18,169,200,196,135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,
		250,124,123,5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,
		189,28,42,223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167,
		43,172,9,129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,
		97,228,251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,
		107,49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
		138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180
	};
	this->m_permutations.insert(this->m_permutations.end(), this->m_permutations.begin(), this->m_permutations.end());
}
uf::PerlinNoise::PerlinNoise(std::size_t seed) {
	this->seed(seed);
}
std::size_t uf::PerlinNoise::seed() const {
	return this->m_seed;
}
void uf::PerlinNoise::seed( std::size_t seed ) {
	this->m_seed = seed;
	this->m_permutations.clear();
	this->m_permutations.resize(256);

	std::iota(this->m_permutations.begin(), this->m_permutations.end(), 0);
	std::default_random_engine engine(this->m_seed);
	std::shuffle(this->m_permutations.begin(), this->m_permutations.end(), engine);
	this->m_permutations.insert(this->m_permutations.end(), this->m_permutations.begin(), this->m_permutations.end());
}
double uf::PerlinNoise::noise( double x, double y, double z ) const {
	// Find the unit cube that contains the point
	int X = (int) std::floor(x) & 255;
	int Y = (int) std::floor(y) & 255;
	int Z = (int) std::floor(z) & 255;
	// Find relative x, y,z of point in cube
	x -= std::floor(x);
	y -= std::floor(y);
	z -= std::floor(z);
	// Compute fade curves for each of x, y, z
	double u = fade(x);
	double v = fade(y);
	double w = fade(z);
	// P
	auto& p = this->m_permutations;
	// Hash coordinates of the 8 cube corners
	int A = p[X] + Y;
	int AA = p[A] + Z;
	int AB = p[A + 1] + Z;
	int B = p[X + 1] + Y;
	int BA = p[B] + Z;
	int BB = p[B + 1] + Z;
	// Add blended results from 8 corners of cube
	double res = lerp(w, lerp(v, lerp(u, grad(p[AA], x, y, z), grad(p[BA], x-1, y, z)), lerp(u, grad(p[AB], x, y-1, z), grad(p[BB], x-1, y-1, z))), lerp(v, lerp(u, grad(p[AA+1], x, y, z-1), grad(p[BA+1], x-1, y, z-1)), lerp(u, grad(p[AB+1], x, y-1, z-1), grad(p[BB+1], x-1, y-1, z-1))));
	return (res + 1.0)/2.0;
}
double uf::PerlinNoise::fade(double t) const {
	return t * t * t * (t * (t * 6 - 15) + 10);
}
double uf::PerlinNoise::lerp(double t, double a, double b) const {
	return a + t * (b - a);
}
double uf::PerlinNoise::grad(int hash, double x, double y, double z) const {
	int h = hash & 15;
	// Convert lower 4 bits of hash inot 12 gradient directions
	double u = h < 8 ? x : y,
	v = h < 4 ? y : h == 12 || h == 14 ? x : z;
	return ((h & 1) == 0 ? u : -u) + ((h & 2) == 0 ? v : -v);
}
uf::stl::vector<double> uf::PerlinNoise::collect( uint size, const pod::Vector3d& noiseCoeff, const callback_t& callback ) {
	uf::stl::vector<double> res;
	res.reserve( size );
	for(unsigned int i = 0; i < size; ++i) { // x
		double x = (double)i/((double)size);

		double n = this->noise(noiseCoeff.x * x, noiseCoeff.y, noiseCoeff.z);
		callback(n);
		res.push_back(n);
	}
	return res;
}
uf::stl::vector<double> uf::PerlinNoise::collect( const pod::Vector2ui& size, const pod::Vector3d& noiseCoeff, const callback_t& callback ) {
	uf::stl::vector<double> res;
	res.reserve( size.x * size.y );
	for(unsigned int i = 0; i < size.y; ++i) { // y
	for(unsigned int j = 0; j < size.x; ++j) { // x
		double x = (double)j/((double)size.x);
		double y = (double)i/((double)size.y);

		double n = this->noise(noiseCoeff.x * x, noiseCoeff.y * y, noiseCoeff.z);
		callback(n);
		res.push_back(n);
	}
	}
	return res;
}
uf::stl::vector<double> uf::PerlinNoise::collect( const pod::Vector3ui& size, const pod::Vector3d& noiseCoeff, const callback_t& callback ) {
	uf::stl::vector<double> res;
	res.reserve( size.x * size.y * size.z );
	for(unsigned int Z = 0; Z < size.z; ++Z) { // z
	for(unsigned int Y = 0; Y < size.y; ++Y) { // y
	for(unsigned int X = 0; X < size.x; ++X) { // x
		double x = (double) Z / (double) size.x;
		double y = (double) Y / (double) size.y;
		double z = (double) X / (double) size.z;

		double n = this->noise(noiseCoeff.x * x, noiseCoeff.y * y, noiseCoeff.z * z);
		callback(n);
		res.push_back(n);
	}
	}
	}
	return res;
}

double uf::PerlinNoise::sample( const pod::Vector3d& position, const pod::Vector3d& noiseCoeff, const callback_t& callback ) {
	uf::stl::vector<double> res;
	double n = this->noise(noiseCoeff.x * position.x, noiseCoeff.y * position.y, noiseCoeff.z * position.z);
	callback(n);
	return n;
}

double uf::PerlinNoise::sample( const pod::Vector3f& position, const pod::Vector3d& noiseCoeff, const callback_t& callback ) {
	uf::stl::vector<double> res;
	double n = this->noise(noiseCoeff.x * position.x, noiseCoeff.y * position.y, noiseCoeff.z * position.z);
	callback(n);
	return n;
}