#include <stdio.h>
#include <stdlib.h>

#define MAPSIZE 128

#if MAPSIZE>255
#error MAPSIZE must be a short value
#endif

//---------------------------------------------------------------------
// http://www.pixelbeat.org/programming/gcc/static_assert.html
#define ct_assert(e) {enum { ct_assert_value = 1/(!!(e)) };}
//---------------------------------------------------------------------

typedef long long int addr;
typedef struct { //RGB
	unsigned int red : 8;
	unsigned int green : 8;
	unsigned int blue : 8;
} Color; //Used for Bukkit's initializers (for simplicity)
typedef struct { //BGRA
	unsigned int blue : 8;
	unsigned int green : 8;
	unsigned int red : 8;
	unsigned int alpha : 8;
} NativeColor; //Used for the screen data

char matchColor(NativeColor nc);

void* image=NULL;
void* maps=NULL; //Per map data (1st map, second map etc.)

short width, height, mapcx, mapcy;

void setSource(addr address, short w, short h, short mcx, short mcy) {
	ct_assert(sizeof(char)==1); //Compile-time assert
	ct_assert(sizeof(Color)==4); //Compile-time assert
	image=(void*)address;
	maps=malloc(MAPSIZE*MAPSIZE*mcx*mcy); //1 byte per pixel
	width=w, height=h, mapcx=mcx, mapcy=mcy;
	printf("PXC: w=%d h=%d mcx=%d mcy=%d\n", w, h, mcx, mcy);
}

NativeColor* getNativeColor(int x, int y) {
	if(x<0||x>width||y<0||y>height) return NULL;
	return ((NativeColor*)image)+x+y*width;
}

char* getMapColor(int x, int y) {
	if(x<0||x>width||y<0||y>height) return NULL;
	int mc=x/MAPSIZE+y/MAPSIZE*mapcx;
	return maps+mc*MAPSIZE*MAPSIZE; //TODO: Use
}

//May return 0
void* updateAndGetMap(int x, int y, int w, int h, int** out_changed) { //TODO: Support the parameters
	if(image==NULL || maps==NULL) return 0;
	for(int l=y; l<y+h; l++) {
		//printf("PXC: l=%d\n", l);
		for(int k=x; k<x+w; k++) {
			//printf("PXC: k=%d\n", k);
			char *mapp=getMapColor(k, l);
			char color=matchColor(*getNativeColor(k, l));
			//NativeColor x={.red=0, .green=0, .blue=255, .alpha=255};
			//*mapp=matchColor(x);
			*mapp=color;
			//printf("PXC: mapp: %d %d - %x\n", k, l, *mapp);	//TODO: The bottom of the image
			//printf("PXC: mapcx: %d mapcy: %d\n", k, l); 		//TODO: Has nothing
		}
	}
	printf("PXC: ret maps=%p\n", maps);
	return maps; //TODO: Return changed only
}

const Color colors[] = {
	{0, 0, 0}, {0, 0, 0}, {0, 0, 0}, {0, 0, 0},
	{89, 125, 39}, {109, 153, 48}, {127, 178, 56}, {67, 94, 29},
	{174, 164, 115}, {213, 201, 140}, {247, 233, 163}, {130, 123, 86},
	{140, 140, 140}, {171, 171, 171}, {199, 199, 199}, {105, 105, 105},
	{180, 0, 0}, {220, 0, 0}, {255, 0, 0}, {135, 0, 0},
	{112, 112, 180}, {138, 138, 220}, {160, 160, 255}, {84, 84, 135},
	{117, 117, 117}, {144, 144, 144}, {167, 167, 167}, {88, 88, 88},
	{0, 87, 0}, {0, 106, 0}, {0, 124, 0}, {0, 65, 0},
	{180, 180, 180}, {220, 220, 220}, {255, 255, 255}, {135, 135, 135},
	{115, 118, 129}, {141, 144, 158}, {164, 168, 184}, {86, 88, 97},
	{106, 76, 54}, {130, 94, 66}, {151, 109, 77}, {79, 57, 40},
	{79, 79, 79}, {96, 96, 96}, {112, 112, 112}, {59, 59, 59},
	{45, 45, 180}, {55, 55, 220}, {64, 64, 255}, {33, 33, 135},
	{100, 84, 50}, {123, 102, 62}, {143, 119, 72}, {75, 63, 38},
	{180, 177, 172}, {220, 217, 211}, {255, 252, 245}, {135, 133, 129},
	{152, 89, 36}, {186, 109, 44}, {216, 127, 51}, {114, 67, 27},
	{125, 53, 152}, {153, 65, 186}, {178, 76, 216}, {94, 40, 114},
	{72, 108, 152}, {88, 132, 186}, {102, 153, 216}, {54, 81, 114},
	{161, 161, 36}, {197, 197, 44}, {229, 229, 51}, {121, 121, 27},
	{89, 144, 17}, {109, 176, 21}, {127, 204, 25}, {67, 108, 13},
	{170, 89, 116}, {208, 109, 142}, {242, 127, 165}, {128, 67, 87},
	{53, 53, 53}, {65, 65, 65}, {76, 76, 76}, {40, 40, 40},
	{108, 108, 108}, {132, 132, 132}, {153, 153, 153}, {81, 81, 81},
	{53, 89, 108}, {65, 109, 132}, {76, 127, 153}, {40, 67, 81},
	{89, 44, 125}, {109, 54, 153}, {127, 63, 178}, {67, 33, 94},
	{36, 53, 125}, {44, 65, 153}, {51, 76, 178}, {27, 40, 94},
	{72, 53, 36}, {88, 65, 44}, {102, 76, 51}, {54, 40, 27},
	{72, 89, 36}, {88, 109, 44}, {102, 127, 51}, {54, 67, 27},
	{108, 36, 36}, {132, 44, 44}, {153, 51, 51}, {81, 27, 27},
	{17, 17, 17}, {21, 21, 21}, {25, 25, 25}, {13, 13, 13},
	{176, 168, 54}, {215, 205, 66}, {250, 238, 77}, {132, 126, 40},
	{64, 154, 150}, {79, 188, 183}, {92, 219, 213}, {48, 115, 112},
	{52, 90, 180}, {63, 110, 220}, {74, 128, 255}, {39, 67, 135},
	{0, 153, 40}, {0, 187, 50}, {0, 217, 58}, {0, 114, 30},
	{91, 60, 34}, {111, 74, 42}, {129, 86, 49}, {68, 45, 25},
	{79, 1, 0}, {96, 1, 0}, {112, 2, 0}, {59, 1, 0},
	{147, 124, 113}, {180, 152, 138}, {209, 177, 161}, {110, 93, 85},
	{112, 57, 25}, {137, 70, 31}, {159, 82, 36}, {84, 43, 19},
	{105, 61, 76}, {128, 75, 93}, {149, 87, 108}, {78, 46, 57},
	{79, 76, 97}, {96, 93, 119}, {112, 108, 138}, {59, 57, 73},
	{131, 93, 25}, {160, 114, 31}, {186, 133, 36}, {98, 70, 19},
	{72, 82, 37}, {88, 100, 45}, {103, 117, 53}, {54, 61, 28},
	{112, 54, 55}, {138, 66, 67}, {160, 77, 78}, {84, 40, 41},
	{40, 28, 24}, {49, 35, 30}, {57, 41, 35}, {30, 21, 18},
	{95, 75, 69}, {116, 92, 84}, {135, 107, 98}, {71, 56, 51},
	{61, 64, 64}, {75, 79, 79}, {87, 92, 92}, {46, 48, 48},
	{86, 51, 62}, {105, 62, 75}, {122, 73, 88}, {64, 38, 46},
	{53, 43, 64}, {65, 53, 79}, {76, 62, 92}, {40, 32, 48},
	{53, 35, 24}, {65, 43, 30}, {76, 50, 35}, {40, 26, 18},
	{53, 57, 29}, {65, 70, 36}, {76, 82, 42}, {40, 43, 22},
	{100, 42, 32}, {122, 51, 39}, {142, 60, 46}, {75, 31, 24},
	{26, 15, 11}, {31, 18, 13}, {37, 22, 16}, {19, 11, 8}
};


//Code from Bukkit's MapPalette class
double getDistance(Color c1, Color c2) {
	double rmean = (c1.red + c2.red) / 2.0;
	double r = c1.red - c2.red;
	double g = c1.green - c2.green;
	int b = c1.blue - c2.blue;
	double weightR = 2 + rmean / 256.0;
	double weightG = 4.0;
	double weightB = 2 + (255 - rmean) / 256.0;
	return weightR * r * r + weightG * g * g + weightB * b * b;
}

//Code from Bukkit's MapPalette class
char matchColor(NativeColor nc) {
	//if (nc.alpha < 128) return 0;
	Color color={.red=nc.red, .green=nc.green, .blue=nc.blue};

	char index = 0;
	double best = -1;

	for (short i = 4; i < sizeof(colors)/sizeof(Color); i++) {
		double distance = getDistance(color, colors[i]);
		if (distance < best || best == -1) {
			best = distance;
			index = i;
		}
	}

	// Minecraft has 143 colors, some of which have negative byte representations
	//return (byte) (index < 128 ? index : -129 + (index - 127));
	return index;
}

//Testing only
int convert(int px[], int *out[]) {
	printf("convert...\n");
	printf("px0: %d\n", px[0]);
	*out[0]=19;
	return 0;
}

void __attribute__ ((constructor)) initLibrary(void) {
 //
 // Function that is called when the library is loaded
 //
    printf("Library is initialized\n"); 
}
void __attribute__ ((destructor)) cleanUpLibrary(void) {
 //
 // Function that is called when the library is »closed«.
 //
    printf("Library is exited\n"); 
}