#include "EmberCLPch.h"
#include "FunctionMapper.h"

namespace EmberCLns
{
std::unordered_map<string, string> FunctionMapper::s_GlobalMap;

FunctionMapper::FunctionMapper()
{
	if (s_GlobalMap.empty())
	{
		s_GlobalMap["LRint"] =
			"inline real_t LRint(real_t x)\n"
			"{\n"
			"    intPrec temp = (x >= 0.0 ? (intPrec)(x + 0.5) : (intPrec)(x - 0.5));\n"
			"    return (real_t)temp;\n"
			"}\n";
		s_GlobalMap["Round"] =
			"inline real_t Round(real_t r)\n"
			"{\n"
			"	return (r > 0.0) ? floor(r + 0.5) : ceil(r - 0.5);\n"
			"}\n";
		s_GlobalMap["Sign"] =
			"inline real_t Sign(real_t v)\n"
			"{\n"
			"	return (v < 0.0) ? -1 : (v > 0.0) ? 1 : 0.0;\n"
			"}\n";
		s_GlobalMap["SignNz"] =
			"inline real_t SignNz(real_t v)\n"
			"{\n"
			"	return (v < 0.0) ? -1.0 : 1.0;\n"
			"}\n";
		s_GlobalMap["Sqr"] =
			"inline real_t Sqr(real_t v)\n"
			"{\n"
			"	return v * v;\n"
			"}\n";
		s_GlobalMap["SafeSqrt"] =
			"inline real_t SafeSqrt(real_t x)\n"
			"{\n"
			"	if (x <= 0.0)\n"
			"		return 0.0;\n"
			"\n"
			"	return sqrt(x);\n"
			"}\n";
		s_GlobalMap["SafeDivInv"] =
			"inline real_t SafeDivInv(real_t q, real_t r)\n"
			"{\n"
			"	if (r < EPS)\n"
			"		return 1 / r;\n"
			"\n"
			"	return q / r;\n"
			"}\n";
		s_GlobalMap["Cube"] =
			"inline real_t Cube(real_t v)\n"
			"{\n"
			"	return v * v * v;\n"
			"}\n";
		s_GlobalMap["Hypot"] =
			"inline real_t Hypot(real_t x, real_t y)\n"
			"{\n"
			"	return sqrt(SQR(x) + SQR(y));\n"
			"}\n";
		s_GlobalMap["Spread"] =
			"inline real_t Spread(real_t x, real_t y)\n"
			"{\n"
			"	return Hypot(x, y) * ((x) > 0.0 ? 1.0 : -1.0);\n"
			"}\n";
		s_GlobalMap["Powq4"] =
			"inline real_t Powq4(real_t x, real_t y)\n"
			"{\n"
			"	return pow(fabs(x), y) * SignNz(x);\n"
			"}\n";
		s_GlobalMap["Powq4c"] =
			"inline real_t Powq4c(real_t x, real_t y)\n"
			"{\n"
			"	return y == 1.0 ? x : Powq4(x, y);\n"
			"}\n";
		s_GlobalMap["Zeps"] =
			"inline real_t Zeps(real_t x)\n"
			"{\n"
			"	return x == 0.0 ? EPS : x;\n"
			"}\n";
		s_GlobalMap["Lerp"] =
			"inline real_t Lerp(real_t a, real_t b, real_t p)\n"
			"{\n"
			"	return a + (b - a) * p;\n"
			"}\n";
		s_GlobalMap["Fabsmod"] =
			"inline real_t Fabsmod(real_t v)\n"
			"{\n"
			"	real_t dummy;\n"
			"\n"
			"	return modf(v, &dummy);\n"
			"}\n";
		s_GlobalMap["Fosc"] =
			"inline real_t Fosc(real_t p, real_t amp, real_t ph)\n"
			"{\n"
			"	return 0.5 - cos(p * amp + ph) * 0.5;\n"
			"}\n";
		s_GlobalMap["Foscn"] =
			"inline real_t Foscn(real_t p, real_t ph)\n"
			"{\n"
			"	return 0.5 - cos(p + ph) * 0.5;\n"
			"}\n";
		s_GlobalMap["LogScale"] =
			"inline real_t LogScale(real_t x)\n"
			"{\n"
			"	return x == 0.0 ? 0.0 : log((fabs(x) + 1) * M_E) * SignNz(x) / M_E;\n"
			"}\n";
		s_GlobalMap["LogMap"] =
			"inline real_t LogMap(real_t x)\n"
			"{\n"
			"	return x == 0.0 ? 0.0 : (M_E + log(x * M_E)) * 0.25 * SignNz(x);\n"
			"}\n";
		s_GlobalMap["ClampGte"] =
			"inline real_t ClampGte(real_t val, real_t gte)\n"
			"{\n"
			"	return (val < gte) ? gte : val;\n"
			"}\n";
		s_GlobalMap["Swap"] =
			"inline void Swap(real_t* val1, real_t* val2)\n"
			"{\n"
			"	real_t tmp = *val1;\n"
			"	*val1 = *val2;\n"
			"	*val2 = tmp;\n"
			"}\n";
		s_GlobalMap["Vratio"] =
			"inline real_t Vratio(real2* p, real2* q, real2* u)\n"
			"{\n"
			"	real2 pmq = *p - *q;\n"
			"\n"
			"	if (pmq.x == 0 && pmq.y == 0)\n"
			"		return 1.0;\n"
			"\n"
			"	return 2 * (((*u).x - (*q).x) * pmq.x + ((*u).y - (*q).y) * pmq.y) / Zeps(SQR(pmq.x) + SQR(pmq.y));\n"
			"}\n";
		s_GlobalMap["Closest"] =
			"inline int Closest(real2* p, int n, real2* u)\n"
			"{\n"
			"	real_t d2;\n"
			"	real_t d2min = TMAX;\n"
			"	int i, j = 0;\n"
			"\n"
			"	for (i = 0; i < n; i++)\n"
			"	{\n"
			"		d2 = Sqr(p[i].x - (*u).x) + Sqr(p[i].y - (*u).y);\n"
			"\n"
			"		if (d2 < d2min)\n"
			"		{\n"
			"			d2min = d2;\n"
			"			j = i;\n"
			"		}\n"
			"	}\n"
			"\n"
			"	return j;\n"
			"}\n";
		s_GlobalMap["Voronoi"] =
			"inline real_t Voronoi(real2* p, int n, int q, real2* u)\n"
			"{\n"
			"	real_t ratio;\n"
			"	real_t ratiomax = TLOW;\n"
			"	int i;\n"
			"\n"
			"	for (i = 0; i < n; i++)\n"
			"	{\n"
			"		if (i != q)\n"
			"		{\n"
			"			ratio = Vratio(&p[i], &p[q], u);\n"
			"\n"
			"			if (ratio > ratiomax)\n"
			"				ratiomax = ratio;\n"
			"		}\n"
			"	}\n"
			"\n"
			"	return ratiomax;\n"
			"}\n";
		s_GlobalMap["SimplexNoise3D"] =
			"inline real_t SimplexNoise3D(real3* v, __global real_t* p, __global real3* grad)\n"
			"{\n"
			"	real3 c[4];\n"
			"	real_t n = 0;\n"
			"	int gi[4];\n"
			"	real_t t;\n"
			"	real_t skewIn = ((*v).x + (*v).y + (*v).z) * 0.333333;\n"
			"	int i = (int)floor((*v).x + skewIn);\n"
			"	int j = (int)floor((*v).y + skewIn);\n"
			"	int k = (int)floor((*v).z + skewIn);\n"
			"	t = (i + j + k) * 0.1666666;\n"
			"	real_t x0 = i - t;\n"
			"	real_t y0 = j - t;\n"
			"	real_t z0 = k - t;\n"
			"	c[0].x = (*v).x - x0;\n"
			"	c[0].y = (*v).y - y0;\n"
			"	c[0].z = (*v).z - z0;\n"
			"	int i1, j1, k1;\n"
			"	int i2, j2, k2;\n"
			"\n"
			"	if (c[0].x >= c[0].y)\n"
			"	{\n"
			"		if (c[0].y >= c[0].z)\n"
			"		{\n"
			"			i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 1; k2 = 0;\n"
			"		}\n"
			"		else\n"
			"		{\n"
			"			if (c[0].x >= c[0].z)\n"
			"			{\n"
			"				i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 0; k2 = 1;\n"
			"			}\n"
			"			else\n"
			"			{\n"
			"				i1 = 0; j1 = 0; k1 = 1; i2 = 1; j2 = 0; k2 = 1;\n"
			"			}\n"
			"		}\n"
			"	}\n"
			"	else\n"
			"	{\n"
			"		if (c[0].y < c[0].z)\n"
			"		{\n"
			"			i1 = 0; j1 = 0; k1 = 1; i2 = 0; j2 = 1; k2 = 1;\n"
			"		}\n"
			"		else\n"
			"		{\n"
			"			if (c[0].x < c[0].z)\n"
			"			{\n"
			"				i1 = 0; j1 = 1; k1 = 0; i2 = 0; j2 = 1; k2 = 1;\n"
			"			}\n"
			"			else\n"
			"			{\n"
			"				i1 = 0; j1 = 1; k1 = 0; i2 = 1; j2 = 1; k2 = 0;\n"
			"			}\n"
			"		}\n"
			"	}\n"
			"\n"
			"	c[1].x = c[0].x - i1 + 0.1666666;\n"
			"	c[1].y = c[0].y - j1 + 0.1666666;\n"
			"	c[1].z = c[0].z - k1 + 0.1666666;\n"
			"	c[2].x = c[0].x - i2 + 2 * 0.1666666;\n"
			"	c[2].y = c[0].y - j2 + 2 * 0.1666666;\n"
			"	c[2].z = c[0].z - k2 + 2 * 0.1666666;\n"
			"	c[3].x = c[0].x - 1 + 3 * 0.1666666;\n"
			"	c[3].y = c[0].y - 1 + 3 * 0.1666666;\n"
			"	c[3].z = c[0].z - 1 + 3 * 0.1666666;\n"
			"	int ii = i & 0x3ff;\n"
			"	int jj = j & 0x3ff;\n"
			"	int kk = k & 0x3ff;\n"
			"	gi[0] = (int)p[ii + (int)p[jj + (int)p[kk]]];\n"
			"	gi[1] = (int)p[ii + i1 + (int)p[jj + j1 + (int)p[kk + k1]]];\n"
			"	gi[2] = (int)p[ii + i2 + (int)p[jj + j2 + (int)p[kk + k2]]];\n"
			"	gi[3] = (int)p[ii + 1 + (int)p[jj + 1 + (int)p[kk + 1]]];\n"
			"	for (uint corner = 0; corner < 4; corner++)\n"
			"	{\n"
			"		t = 0.6 - Sqr(c[corner].x) - Sqr(c[corner].y) - Sqr(c[corner].z);\n"
			"\n"
			"		if (t > 0)\n"
			"		{\n"
			"			real3 u = grad[gi[corner]];\n"
			"			t *= t;\n"
			"			n += t * t * (u.x * c[corner].x + u.y * c[corner].y + u.z * c[corner].z);\n"
			"		}\n"
			"	}\n"
			"\n"
			"	return 32 * n;\n"
			"}\n";
		s_GlobalMap["PerlinNoise3D"] =
			"inline real_t PerlinNoise3D(real3* v, __global real_t* p, __global real3* grad, real_t aScale, real_t fScale, int octaves)\n"
			"{\n"
			"	int i;\n"
			"	real_t n = 0, a = 1;\n"
			"	real3 u = *v;\n"
			"\n"
			"	for (i = 0; i < octaves; i++)\n"
			"	{\n"
			"		n += SimplexNoise3D(&u, p, grad) / Zeps(a);\n"
			"		a *= aScale;\n"
			"		u.x *= fScale;\n"
			"		u.y *= fScale;\n"
			"		u.x *= fScale;\n"
			"	}\n"
			"\n"
			"	return n;\n"
			"}\n";
		s_GlobalMap["JacobiElliptic"] =
			"inline void JacobiElliptic(real_t uu, real_t emmc, real_t* sn, real_t* cn, real_t* dn)\n"
			"{\n"
			"	real_t CA = 0.0003;\n"
			"	real_t a, b, c, d = 1, em[13], en[13];\n"
			"	int bo;\n"
			"	int l;\n"
			"	int ii;\n"
			"	int i;\n"
			"	real_t emc = emmc;\n"
			"	real_t u = uu;\n"
			"\n"
			"	if (emc != 0)\n"
			"	{\n"
			"		bo = 0;\n"
			"\n"
			"		if (emc < 0)\n"
			"			bo = 1;\n"
			"\n"
			"		if (bo != 0)\n"
			"		{\n"
			"			d = 1 - emc;\n"
			"			emc = -emc / d;\n"
			"			d = sqrt(d);\n"
			"			u = d * u;\n"
			"		}\n"
			"\n"
			"		a = 1;\n"
			"		*dn = 1;\n"
			"\n"
			"		for (i = 0; i < 8; i++)\n"
			"		{\n"
			"			l = i;\n"
			"			em[i] = a;\n"
			"			emc = sqrt(emc);\n"
			"			en[i] = emc;\n"
			"			c = 0.5 * (a + emc);\n"
			"\n"
			"			if (fabs(a - emc) <= CA * a)\n"
			"				break;\n"
			"\n"
			"			emc = a * emc;\n"
			"			a = c;\n"
			"		}\n"
			"\n"
			"		u = c * u;\n"
			"		*sn = sincos(u, cn);\n"
			"\n"
			"		if (*sn != 0)\n"
			"		{\n"
			"			a = *cn / *sn;\n"
			"			c = a * c;\n"
			"\n"
			"			for (ii = l; ii >= 0; --ii)\n"
			"			{\n"
			"				b = em[ii];\n"
			"				a = c * a;\n"
			"				c = *dn * c;\n"
			"				*dn = (en[ii] + a) / (b + a);\n"
			"				a = c / b;\n"
			"			}\n"
			"\n"
			"			a = 1 / sqrt(c * c + 1);\n"
			"\n"
			"			if (*sn < 0)\n"
			"				*sn = -a;\n"
			"			else\n"
			"				*sn = a;\n"
			"\n"
			"			*cn = c * *sn;\n"
			"		}\n"
			"\n"
			"		if (bo != 0)\n"
			"		{\n"
			"			a = *dn;\n"
			"			*dn = *cn;\n"
			"			*cn = a;\n"
			"			*sn = *sn / d;\n"
			"		}\n"
			"	}\n"
			"	else\n"
			"	{\n"
			"		*cn = 1 / cosh(u);\n"
			"		*dn = *cn;\n"
			"		*sn = tanh(u);\n"
			"	}\n"
			"}\n";
	}
}

/// <summary>
/// Get a pointer to the text of the global function whose name is the passed in string.
/// </summary>
/// <param name="func">The function name to retrieve</param>
/// <returns>A pointer to the function body string if found, else nullptr.</returns>
const string* FunctionMapper::GetGlobalFunc(const string& func)
{
	const auto& text = s_GlobalMap.find(func);

	if (text != s_GlobalMap.end())
		return &text->second;
	else
		return nullptr;
}
}
