/*
	Little Smalltalk, version 3
	Written by Tim Budd, Oregon State University, June 1988

	routines used in reading in textual descriptions of classes
*/

# include <stdio.h>
# include "env.h"
# include "memory.h"
# include "names.h"
# include "lex.h"
# ifdef STRING
# include <string.h>
# endif
# ifdef STRINGS
# include <strings.h>
# endif

# define MethodTableSize 39

/*
	the following are switch settings, with default values
*/
boolean savetext = true;

/*
	we read the input a line at a time, putting lines into the following
	buffer.  In addition, all methods must also fit into this buffer.
*/
# define TextBufferSize 1024
static char textBuffer[TextBufferSize];

/*
	findClass gets a class object,
	either by finding it already or making it
	in addition, it makes sure it has a size, by setting
	the size to zero if it is nil.
*/
static object findClass(name)
char *name;
{	object newobj;

	newobj = globalSymbol(name);
	if (newobj == nilobj)
		newobj = newClass(name);
	if (basicAt(newobj, sizeInClass) == nilobj) {
		basicAtPut(newobj, sizeInClass, newInteger(0));
		}
	return newobj;
}

/*
	readDeclaration reads a declaration of a class
*/
static readClassDeclaration()
{	object classObj, super, vars;
	int i, size, instanceTop;
	object instanceVariables[15];

	if (nextToken() != nameconst)
		sysError("bad file format","no name in declaration");
	classObj = findClass(tokenString);
	size = 0;
	if (nextToken() == nameconst) {	/* read superclass name */
		super = findClass(tokenString);
		basicAtPut(classObj, superClassInClass, super);
		size = intValue(basicAt(super, sizeInClass));
		ignore nextToken();
		}
	if (token == nameconst) {		/* read instance var names */
		instanceTop = 0;
		while (token == nameconst) {
			instanceVariables[instanceTop++] = newSymbol(tokenString);
			size++;
			ignore nextToken();
			}
		vars = newArray(instanceTop);
		for (i = 0; i < instanceTop; i++) {
			basicAtPut(vars, i+1, instanceVariables[i]);
			}
		basicAtPut(classObj, variablesInClass, vars);
		}
	basicAtPut(classObj, sizeInClass, newInteger(size));
}

/*
	readClass reads a class method description
*/
static readMethods(fd, printit)
FILE *fd;
boolean printit;
{	object classObj, methTable, theMethod, selector;
# define LINEBUFFERSIZE 512
	char *cp, *eoftest, lineBuffer[LINEBUFFERSIZE];

	if (nextToken() != nameconst)
		sysError("missing name","following Method keyword");
	classObj = findClass(tokenString);
	setInstanceVariables(classObj);
	if (printit)
		cp = charPtr(basicAt(classObj, nameInClass));

	/* now find or create a method table */
	methTable = basicAt(classObj, methodsInClass);
	if (methTable == nilobj) {	/* must make */
		methTable = newDictionary(MethodTableSize);
		basicAtPut(classObj, methodsInClass, methTable);
		}

	/* now go read the methods */
	do {
		if (lineBuffer[0] == '|')	/* get any left over text */
			strcpy(textBuffer,&lineBuffer[1]);
		else
			textBuffer[0] = '\0';
		while((eoftest = fgets(lineBuffer, LINEBUFFERSIZE, fd)) != NULL) {
			if ((lineBuffer[0] == '|') || (lineBuffer[0] == ']'))
				break;
			ignore strcat(textBuffer, lineBuffer);
			}
		if (eoftest == NULL) {
			sysError("unexpected end of file","while reading method");
			break;
			}

		/* now we have a method */
		theMethod = newMethod();
		if (parse(theMethod, textBuffer, savetext)) {
			selector = basicAt(theMethod, messageInMethod);
			basicAtPut(theMethod, methodClassInMethod, classObj);
			if (printit)
				dspMethod(cp, charPtr(selector));
			nameTableInsert(methTable, (int) selector, 
				selector, theMethod);
			}
		else {
			/* get rid of unwanted method */
			incr(theMethod);
			decr(theMethod);
			givepause();
			}
		
	} while (lineBuffer[0] != ']');
}

/*
	fileIn reads in a module definition
*/
fileIn(fd, printit)
FILE *fd;
boolean printit;
{
	while(fgets(textBuffer, TextBufferSize, fd) != NULL) {
		lexinit(textBuffer);
		if (token == inputend)
			; /* do nothing, get next line */
		else if ((token == binary) && streq(tokenString, "*"))
			; /* do nothing, its a comment */
		else if ((token == nameconst) && streq(tokenString, "Class"))
			readClassDeclaration();
		else if ((token == nameconst) && streq(tokenString,"Methods"))
			readMethods(fd, printit);
		else 
			sysError("unrecognized line", textBuffer);
		}
}