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

struct INPUT
{
	int lnum;
	char line[99];
	struct INPUT *nextPtr;
};

struct TABLEENTRY
{
	int symbol;
	char type;
	int location;
};

typedef struct INPUT input;
typedef input *inputPtr;
typedef struct TABLEENTRY tableEntry;

void insert(int, inputPtr *, char *);
void tableIns(char *, char);
int search(int, char *);

tableEntry symbolTable[99];
int sml[99];	// array for sml
int flags[99];              // flag unresolved gotos
int instructionCounter = 0; // keep track of how many instructions
int tableLocation = 0;      // store the current place in symbolTable
int variables = 99;         // for variables
char currentcmd[99];


// ------------------------

void main(void)
{
inputPtr startPtr = NULL;
inputPtr currentPtr = NULL;
char commandline[99];
char commandline2[99];
char variableName;
int i, q;
int total = 0;
int n = 0;
int sentinel = 1;
int dog = 0;

/* initialize all of flags to -1 */
for(i = 0; i<100; i++)
 flags[i] = -1;

printf("\nSIMPLE to SML converter.\n");

while(dog != 1)
{
printf("? ");
gets(commandline);
if(strlen(commandline) == 0)
 dog = 1;
strcpy(commandline2, commandline);
insert((int)strtol(strtok(commandline, " "),NULL,10), &startPtr, commandline);
total++;
}


/* do pass 1 */
for(i=0; i < total; i++)
{
	/* set currentPtr to the current part of the linklist */
	currentPtr->nextPtr = startPtr->nextPtr;
	for(n=0; n < i; n++)
	{
		currentPtr = currentPtr->nextPtr;
	}

	/* tokenize currentPtr and put into symbol table */
	q=0; // keeps track of where we are in the current commandline
	strcpy(currentcmd, strtok(commandline, " "));

	while(sentinel)
	{
		// first part is a line number
		if(q == 0)
		{
			// search, if not found, then install
			if(search((int)strtol(currentcmd, NULL, 10), NULL) == -1)
				tableIns(currentcmd, 'L');
		}
		else
		
		strtok(NULL, " "); // get new one
	
		// second part is a command
		if(q == 1)
		{
			// rem statement
			if(strcmp(currentcmd, "REM") == 0)
				sentinel = 0;		


			// input statement
			if(strcmp(currentcmd, "INPUT") == 0)
			{
				// store the following variable in the table
				strcpy(variableName, strtok(NULL," "));
				tableIns(variableName, "V");
				sml[instructionCounter] = 1000 + search(NULL, variableName);
				instructionCounter++; 
				sentinel = 0;
			}	

			// print / write statement
			if(strcmp(currentcmd, "PRINT") == 0)
			{
				// store the following variable in the table
				strcpy(variableName, strtok(NULL, " "));
				tableIns(variableName, "V");
				sml[instructionCounter] = 1100 + search(NULL, variableName);
				instructionCounter++;
				sentinel = 0;
			}


		}

	++q;
	}	

}

/* do pass 2 */

}

/* ---------------------------- */

void insert(int lnum, inputPtr *ip, char *line)
{
inputPtr newPtr, previousPtr, currentPtr;

newPtr = malloc(sizeof(input));

if(newPtr != NULL )
{
	strcpy(newPtr->line, line);
	newPtr->nextPtr = NULL;
	
	previousPtr = NULL;
	currentPtr = *ip;

	while(currentPtr!=NULL &&lnum > currentPtr->lnum)
	{
		previousPtr = currentPtr;
		currentPtr = currentPtr->nextPtr;
	}

	if(previousPtr == NULL)
	{
		newPtr->nextPtr = *ip;
		*ip = newPtr;
	}
	
	else
	{
		previousPtr->nextPtr = newPtr;
		newPtr->nextPtr = currentPtr;
	}

} /* end if */

else
	printf("No memory available.\n");
} /* end function */


void tableIns(char *symbol, char type)
{
	if(strcmp(type, "L") == 0)
	{
		symbolTable[tableLocation].symbol = (int)strtol(currentcmd, NULL, 10);
		strcpy(symbolTable[tableLocation].type, "L");
		symbolTable[tableLocation].location = instructionCounter;
		tableLocation++;
	}

	if(strcmp(type, "V") == 0)
	{
		strcpy(symbolTable[tableLocation].symbol, symbol);
		strcpy(symbolTable[tableLocation].type, "V");
		symbolTable[tableLocation].location = variables--;
	}

}


int search(int number, char *nonNumber)
{
int i;

// searching for number?
	if(number != NULL)
	{
		for(i = 0; i < 100; i++)
		{
			if(symbolTable[i].symbol == number)
				return symbolTable[i].location; // found
		}
			
		return -1; // not found
	}

// searching for variable or keyword
	if(nonNumber != NULL)
	{
		for(i = 0; i < 100; i++)
		{
			if(strcmp(symbolTable[i].symbol, nonNumber == 0))
				return symbolTable[i].location; // found
		}
		
		return -1; // not found
	}

}