#include "svibe.h"
#include <stdlib.h>

void RegionSurveillance::RandInit()
{
	flag = 0;
	i_rand = 0;

	int tempX[8] = {2, 2, 1, 0, 0, 0, 1, 2};
	int tempY[8] = {1, 0, 0, 0, 1, 2, 2, 2};
	for (int tmpi = 0; tmpi < 8; tmpi++)
	{
		g_XNeighborTable[tmpi] = tempX[tmpi];
		g_YNeighborTable[tmpi] = tempY[tmpi];
	}

	if (flag == 0)
	{
		int32_t i = 0;
		g_randTable = (uint32_t *) malloc(0x10000 * sizeof(uint32_t));
		
		for (i = 0; i < 0x10000; i++)
		{
			g_randTable[i] = (uint32_t)(rand());
		}		
	}
}

uint32_t RegionSurveillance::GetRand()
{
	//static uint32_t i = 0;
	//uint32_t i_rand = 0;
	return g_randTable[0xFFFF & i_rand++];
}

void RegionSurveillance::FreeRand()
{
	free(g_randTable);
}

// static int32_t *g_XTable;
// static int32_t *g_YTable;
// static int32_t g_XNeighborTable[8] = {2, 2, 1, 0, 0, 0, 1, 2};
// static int32_t g_YNeighborTable[8] = {1, 0, 0, 0, 1, 2, 2, 2};

void RegionSurveillance::RandNeighborInit(int32_t width, int32_t height)
{
	//static int32_t flag = 0;
	int32_t i;
	if (flag == 0)
	{
		flag = 1;
		g_XTable = (int32_t *)malloc((width + 2) * sizeof(int32_t));
		for (i = 0; i < width; i++)
		{
			g_XTable[i + 1] = i;
		}
		g_XTable[0] = 0;
		g_XTable[width + 1] = width - 1;

		g_YTable = (int32_t *)malloc((height + 2) * sizeof(int32_t));
		for (i = 0; i < height; i++)
		{
			g_YTable[i + 1] = i;
		}
		g_XTable[0] = 0;                                              //1
		g_XTable[height + 1] = height - 1;
	}
}

void RegionSurveillance::GetRandNeighborXY(int32_t x, int32_t y, int32_t *_x, int32_t *_y)
{
	uint32_t r = GetRand() & 0x07;
	*_x = g_XTable[x + g_XNeighborTable[r]];
	*_y = g_XTable[y + g_YNeighborTable[r]];
}

void RegionSurveillance::GetNeighborXY(int32_t x, int32_t y, int32_t *_x, int32_t *_y, int32_t flag)
{
	*_x = g_XTable[x + g_XNeighborTable[flag]];
	*_y = g_XTable[y + g_YNeighborTable[flag]];
}

void RegionSurveillance::FreeRandNeighbor()
{
	free(g_XTable);
	free(g_YTable);
}