//	Huffman coding version by 3Com Palm Computing, Inc.
//	dfm: 7/13/99 
//	Modified by MLF 11/19/99 for generic Public Domain

// Some more standard types - MLF
#define UInt8	unsigned char
#define Int16	short
#define UInt16	unsigned short
#define TRUE	1
#define FALSE	0


#define	oneFlag		0x01


// The number of Loops and Stations from WirelessXXX.STA
int iNumberOfDataStations;

// An array that holds the expanded data from WirelessXXX.DAT
int iRoadwayData[1000];

// One byte value for expresslane direction
unsigned char ucExpressLanes;

// Value of the most current data stream
unsigned char ucVersion;

// Time stamp of current data 
short sYear, sMonth, sDay, sHour, sMinute;


// Constant values for colors of roaday segments
// Developers will want to change these to RGB or color indexes of the target system.
#define GREEN	1
#define YELLOW	2
#define	RED		3
#define	BLACK	4
#define NO_DATA	5


// GENERAL INSTRUCTIONS:
// Open the file WirelessXXX.DAT and read into a buffer.
// Call this function with a pointer to that buffer.
// iRoadwayData[] stores the data to paint a roadway segment.

int ExpandHuffmanData(UInt8 * rawP)
{
	UInt8	currentData;
	Int16	bit = 7;
	UInt16	loop = 0;
	UInt8 *	dP = rawP;
	Int16	byteCount = 0;


	// Get ExpressLane Direction
	ucExpressLanes = *dP++;
	byteCount++;
	
	sYear = *dP++ << 8;
	byteCount++;
	
	sYear += *dP++;
	byteCount++;
	
	sMonth = *dP++;
	byteCount++;
	
	sDay = *dP++;
	byteCount++;
	
	sHour = *dP++;
	byteCount++;
	
	sMinute = *dP++;
	byteCount++;
	
	
	while(loop < iNumberOfDataStations)
	{
		if (bit < 0)
		{
			dP++;
			bit=7;
			byteCount++;
		}
			
		currentData = *dP & (oneFlag << bit);	
		bit--;
	
		
		// 0
		if (currentData == 0x00)
			//0 is signed to WIDE_OPEN on the proxy side
			iRoadwayData[loop++] = GREEN;
			
		// 1
		else
		{
			if(bit < 0)
			{
				dP++;
				bit = 7;
				byteCount++;
			}
			
			currentData = *dP & (oneFlag << bit);
			bit--;
			
			//1 0
			if (currentData == 0x00)
				// 10 is signed to NO_DATA on the proxy
				iRoadwayData[loop++] = NO_DATA;
				
			//1 1 
			else 
			{
				if(bit<0)
				{
					dP++;
					bit = 7;
					byteCount++;
				}
								
				currentData = *dP & (oneFlag << bit);
				bit--;
				
				// 1 1 0
				if (currentData == 0x00)
					//110 is signed to MODERATE on proxy
					iRoadwayData[loop++] = YELLOW;
					
				// 1 1 1
				else
				{
					if(bit<0)
					{
						dP++;
						bit = 7;
						byteCount++;
					}
									
					currentData = *dP & (oneFlag << bit);
					bit--;
					
					// 1 1 1 0
					if (currentData == 0x00)
						//1110 is signed to HEAVY on proxy
						iRoadwayData[loop++] = RED;
						
					// 1 1 1 1
					else
						//1111 is signed to STOP_GO on proxy
						iRoadwayData[loop++] = BLACK;
				}
						
			}		
		}			
	}
	
	if (loop == iNumberOfDataStations)
		return TRUE;
	else
		return FALSE;
}