#include <dirent.h>

#include <sys/stat.h>

#include "private.h"

#include "drawing.h"

int heliInitialized;

HeliArray heliObjectsSet;

struct _Directory {

	size_t pathLen;

	HeliArray files;

};

static const float yuvToRgb[3][3] = {

	{ 1.0,  0.0     ,  1.402    },

	{ 1.0, -0.344136, -0.714136 },

	{ 1.0,  1.772   ,  0.0      } };

static const float rgbToYuv[3][3] = {

	{  0.299   ,  0.587   ,  0.114    },

	{ -0.168736, -0.331264,  0.5      },

	{  0.5     , -0.418688, -0.081312 } };

#include "colors.inc.h"

int randomNumber(int min, int max)

	{ return max <= min ? min : rand()%(max - min + 1) + min; }

double randomFloat()

	{ return (double)rand()/(double)RAND_MAX; }

void rotateVector(double *x, double *y, double angle) {

	double a = angle*PI/180.0;

	double xx = x ? *x : 0.0;

	double yy = y ? *y : 0.0;

	double c = cos(a);

	double s = sin(a);

	if (x) *x = xx*c - yy*s;

	if (y) *y = xx*s + yy*c;

}

Directory openDirectoryEx(

	const char *path,

	const char *prefix,

	const char *suffix,

	int caseSensitive,

	int showFiles,

	int showDirectories )

{

	if (!heliInitialized) return NULL;

	if (!path) return NULL;

	DIR *dir = opendir(path);

	if (!dir) return NULL;

	Directory d = calloc(1, sizeof(*d));

	d->pathLen = strlen(path);

	size_t prefixLen = prefix ? strlen(prefix) : 0u;

	size_t suffixLen = suffix ? strlen(suffix) : 0u;

	size_t bufLen = d->pathLen + 1024;

	char *buf = calloc(1, bufLen);

	strcpy(buf, path);

	if (d->pathLen > 0 && buf[d->pathLen - 1] != '\\' && buf[d->pathLen - 1] != '/') {

		char lastSlash = '/';

		for(const char *c = buf; *c; ++c)

			if (*c == '\\' || *c == '/') lastSlash = *c;

		buf[d->pathLen++] = lastSlash;

	}

	struct dirent *ent;

	while((ent = readdir(dir)) != NULL) {

		if ( !ent->d_name[0]

		  || strcmp(ent->d_name, ".") == 0

		  || strcmp(ent->d_name, "..") == 0 ) continue;

		if (prefixLen) {

			if ( caseSensitive ? strncmp(prefix, ent->d_name, prefixLen)

				               : heliStringCompareNCi(prefix, ent->d_name, prefixLen) )

				continue;

		}

		size_t nameLen = strlen(ent->d_name);

		if (suffixLen) {

			if (nameLen < suffixLen) continue;

			const char *sub = ent->d_name + nameLen - suffixLen;

			if ( caseSensitive ? strcmp(suffix, sub)

				               : heliStringCompareCi(suffix, sub) )

				continue;

		}

		if (bufLen <= d->pathLen + nameLen) {

			bufLen = d->pathLen + nameLen + 1024;

			buf = realloc(buf, bufLen);

		}

		strcpy(buf + d->pathLen, ent->d_name);

		if ( (showFiles && fileExists(buf))

		  || (showDirectories && directoryExists(buf)) )

			heliStringmapAdd(&d->files, buf, NULL, NULL);

	}

	closedir(dir);

	heliObjectRegister(d, (HeliFreeCallback)&closeDirectory);

	return d;

}

Directory openDirectory(const char *path)

	{ return openDirectoryEx(path, NULL, NULL, TRUE, TRUE, TRUE); }

void closeDirectory(Directory directory) {

	if (!directory) return;

	heliObjectUnregister(directory);

	heliArrayDestroy(&directory->files);

	free(directory);

}

int directoryGetCount(Directory directory)

	{ return directory->files.count; }

const char* directoryGetFull(Directory directory, int i)

	{ return (const char*)heliArrayGetKey(&directory->files, i); }

const char* directoryGet(Directory directory, int i) {

	const char *path = directoryGetFull(directory, i);

	return path ? path + directory->pathLen : NULL;

}

int fileExists(const char *path) {

	struct stat s = {};

	return stat(path, &s) == 0 && !(s.st_mode & S_IFDIR);

}

int directoryExists(const char *path) {

	struct stat s = {};

	return stat(path, &s) == 0 && (s.st_mode & S_IFDIR);

}

int makeDirectory(const char *path)

#ifdef WIN32

	{ return directoryExists(path) || !mkdir(path); }

#else

	{ return directoryExists(path) || !mkdir(path, 0777); }

#endif

char* heliStringCopy(const char *x) {

	int len = strlen(x) + 1;

	char *cp = malloc(len);

	memcpy(cp, x, len);

	return cp;

}

char* heliStringCopyLower(const char *x) {

	char *xx = heliStringCopy(x);

	heliStringLower(xx);

	return xx;

}

char* heliStringConcat(const char *a, const char *b) {

	int la = strlen(a);

	int lb = strlen(b);

	char *s = malloc(la + lb + 1);

	memcpy(s, a, la);

	memcpy(s + la, b, lb);

	s[la + lb] = 0;

	return s;

}

char* heliStringConcat3(const char *a, const char *b, const char *c) {

	int la = strlen(a);

	int lb = strlen(b);

	int lc = strlen(c);

	char *s = malloc(la + lb + lc + 1);

	memcpy(s, a, la);

	memcpy(s + la, b, lb);

	memcpy(s + la + lb, c, lc);

	s[la + lb + lc] = 0;

	return s;

}

int heliStringCompareNCi(const char *a, const char *b, size_t n) {

	if (!a && !b) return 0;

	if (!a) return -1;

	if (!b) return 1;

	while((*a || *b) && n) {

		if (!a) return -1;

		if (!b) return 1;

		char aa = tolower(*a);

		char bb = tolower(*b);

		if (aa < bb) return -1;

		if (bb < aa) return 1;

		++a, ++b, --n;

	}

	return 0;

}

int heliStringCompareCi(const char *a, const char *b)

	{ return heliStringCompareNCi(a, b, SIZE_MAX); }

int heliStringEndsWithLowcase(const char *s, const char *tail) {

	int ls = strlen(s);

	int lt = strlen(tail);

	if (lt > ls) return FALSE;

	for(int i = 0; i < lt; ++i)

		if (tolower(s[ls - i]) != tolower(tail[lt - i]))

			return FALSE;

	return TRUE;

}

void heliStringLower(char *x)

	{ while(*x) { *x = tolower(*x); ++x; } }

static double colorClamp(double c)

	{ return c > 0 ? (c < 1 ? c : 1) : 0; }

static unsigned int colorToInt(double c)

	{ return (unsigned int)floor(colorClamp(c)*255.99); }

unsigned int colorWithAlpha(unsigned int colorCode, double a)

	{ return (0xffffff00 & colorCode) | colorToInt(colorGetAlpha(colorCode)*a); }

unsigned int colorByRGBA(double r, double g, double b, double a) {

	return (colorToInt(r) << 24)

	     | (colorToInt(g) << 16)

	     | (colorToInt(b) <<  8)

	     |  colorToInt(a);

}

unsigned int colorByYUVA(double y, double u, double v, double a) {

	return colorByRGBA(

		yuvToRgb[0][0]*y + yuvToRgb[0][1]*u + yuvToRgb[0][2]*v,

		yuvToRgb[1][0]*y + yuvToRgb[1][1]*u + yuvToRgb[1][2]*v,

		yuvToRgb[2][0]*y + yuvToRgb[2][1]*u + yuvToRgb[2][2]*v,

		a );

}

unsigned int colorByHSVA(double h, double s, double v, double a) {

	h -= floor(h/360)*360;

	h /= 60.0;

	int i = (int)h;

	double f = h - i;

	double p = v*(1 - s);

	double q = v*(1 - s*f);

	double t = v*(1 - s*(1 - f));

	switch(i) {

	case 0: return colorByRGBA(v, t, p, a);

	case 1: return colorByRGBA(q, v, p, a);

	case 2: return colorByRGBA(p, v, t, a);

	case 3: return colorByRGBA(p, q, v, a);

	case 4: return colorByRGBA(t, p, v, a);

	case 5: return colorByRGBA(v, p, q, a);

	}

	return colorByRGBA(v, t, p, a);

}

unsigned int colorByRGB(double r, double g, double b)

	{ return colorByRGBA(r, g, b, 1); }

unsigned int colorByHSV(double h, double s, double v)

	{ return colorByHSVA(h, s, v, 1); }

unsigned int colorByYUV(double y, double u, double v)

	{ return colorByYUVA(y, u, v, 1); }

double colorGetRed  (unsigned int colorCode) { return ( colorCode >> 24         )/255.0; }

double colorGetGreen(unsigned int colorCode) { return ((colorCode >> 16) & 0xFFu)/255.0; }

double colorGetBlue (unsigned int colorCode) { return ((colorCode >>  8) & 0xFFu)/255.0; }

double colorGetAlpha(unsigned int colorCode) { return ( colorCode        & 0xFFu)/255.0; }

void heliColorToDouble(unsigned int code, double *rgba) {

	rgba[0] = colorGetRed  (code);

	rgba[1] = colorGetGreen(code);

	rgba[2] = colorGetBlue (code);

	rgba[3] = colorGetAlpha(code);

}

double colorGetYLuminance(unsigned int colorCode) {

	return rgbToYuv[0][0]*colorGetRed  (colorCode)

		 + rgbToYuv[0][1]*colorGetGreen(colorCode)

		 + rgbToYuv[0][2]*colorGetBlue (colorCode);

}

double colorGetUChrominance(unsigned int colorCode) {

	return rgbToYuv[1][0]*colorGetRed  (colorCode)

		 + rgbToYuv[1][1]*colorGetGreen(colorCode)

		 + rgbToYuv[1][2]*colorGetBlue (colorCode);

}

double colorGetVChrominance(unsigned int colorCode) {

	return rgbToYuv[1][0]*colorGetRed  (colorCode)

		 + rgbToYuv[1][1]*colorGetGreen(colorCode)

		 + rgbToYuv[1][2]*colorGetBlue (colorCode);

}

static int colorMin(double *c)

	{ return c[0] < c[1] ? (c[0] < c[2] ? 0 : 2) : (c[1] < c[2] ? 1 : 2); }

static int colorMax(double *c)

	{ return c[0] > c[1] ? (c[0] > c[2] ? 0 : 2) : (c[1] > c[2] ? 1 : 2); }

double colorGetHue(unsigned int colorCode) {

	double rgb[] = { colorGetRed  (colorCode),

	                 colorGetGreen(colorCode),

	                 colorGetBlue (colorCode) };

	int cmin = colorMin(rgb);

	int cmax = colorMax(rgb);

	double d = rgb[cmax] - rgb[cmin];

	double h = 0;

	if (d > HELI_PRECISION) {

		d = 1.0/d;

		switch(cmax){

		case 0: h = (rgb[1] - rgb[2])*d + 0; break;

		case 1: h = (rgb[2] - rgb[0])*d + 2; break;

		case 2: h = (rgb[0] - rgb[1])*d + 4; break;

		}

		h /= 6; h -= floor(h); h *= 360;

	}

	return h;

}

double colorGetSaturation(unsigned int colorCode) {

	double rgb[] = { colorGetRed  (colorCode),

	                 colorGetGreen(colorCode),

	                 colorGetBlue (colorCode) };

	int cmin = colorMin(rgb);

	int cmax = colorMax(rgb);

	return rgb[cmax] > HELI_PRECISION ? (rgb[cmax] - rgb[cmin])/rgb[cmax] : 0;

}

double colorGetValue(unsigned int colorCode) {

	double rgb[] = { colorGetRed  (colorCode),

	                 colorGetGreen(colorCode),

	                 colorGetBlue (colorCode) };

	return rgb[colorMax(rgb)];

}

unsigned int colorByNameA(const char *colorName, double a)

	{ return colorWithAlpha(colorByName(colorName), a); }

unsigned int colorByName(const char *colorName) {

	unsigned int code = 0;

	const char *x = colorName;

	if (*x == '#') {

		++x;

		int hex[8] = { 0, 0, 0, 0, 0, 0, 15, 15 };

		for(int i = 0; *x && i < 8; ++i, ++x) {

			char c = tolower(*x);

			if (c >= '0' && c <= '9') hex[i] = c - '0';

			if (c >= 'a' && c <= 'f') hex[i] = c - 'a' + 10;

		}

		for(int i = 0; i < 6; ++i)

			code |= ( hex[i] << ((7-i)*4) );

		code |= colorToInt( (hex[6]*16 + hex[7])/255.0 );

	} else

	if (isalpha(*x)) {

		int count = (int)(sizeof(colors)/sizeof(*colors));

		for(int i = 0; i < count; ++i)

			if (heliStringCompareCi(x, colors[i].name) == 0)

				return colors[i].code;

	} else {

		double r = 0, g = 0, b = 0, a = 1;

		sscanf(x, "%lf %lf %lf %lf", &r, &g, &b, &a);

		code = colorByRGBA(r, g, b, a);

	}

	return code;

}

static int objectsCompare(const void *a, const void *b)

	{ return a < b ? -1 : b < a ? 1 : 0; }

static void* objectsKeyClone(void *k)

	{ return k; }

void heliObjectRegister(void *o, HeliFreeCallback fo)

	{ heliMapAdd(&heliObjectsSet, o, &objectsCompare, (HeliCloneCallback)objectsKeyClone, fo, NULL, NULL); }

void heliObjectUnregister(void *o) {

	int i;

	HeliPair *item = heliMapFind(&heliObjectsSet, o, &objectsCompare, &i);

	if (item) {

		item->freeKey = NULL;

		heliArrayRemove(&heliObjectsSet, i);

	}

}