/* mkenum.c - turns a list of strings to a C enum */
/* PUBLIC DOMAIN - May 2007 - Jon Mayo */
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

#define MAX_IDENTIFIER	128 /* identifier max length of 127 characters */
#define MAX_STRING		512 /* string literal max length of 511 characters */
#define DEF_PREFIX		"E_"		/* default prefix on identifiers */
#define DEF_ENUM_NAME	"myenum"	/* default name of enum */
#define DEF_TYPEDEF_NAME	NULL 	/* disabled */
#define DEF_STRTAB		"myenum_tab" /* default name of string table */
#define DEF_STRTAB_STATIC	1		/* enable to make string table static */

struct entry {
	char *data;
	struct entry *next;
};

struct entry *new_entry(const char *data) {
	struct entry *ret;
	unsigned len;
	assert(data!=NULL);
	ret=malloc(sizeof *ret);
	assert(ret!=NULL);
	len=strlen(data);
	ret->data=malloc(len+1);
	assert(ret->data!=NULL);
	ret->next=0;
	memcpy(ret->data, data, len+1);
	return ret;
}

int main() {
	struct entry *head, **prev; /* list that is used for string table */
	const char *prefix = DEF_PREFIX; /* prefix to put on each identifier */
	const char *enum_name = DEF_ENUM_NAME; /* must define */
	const char *typedef_name = DEF_TYPEDEF_NAME; /* define to have typedef */
	const char *strtab_name = DEF_STRTAB; /* define to have a table of strings */
	int strtable_static = DEF_STRTAB_STATIC; /* 0/1 to turn on static */
	char buf[MAX_IDENTIFIER]; /* input buffer for reading lines */
	int e_cnt; /* count the enums as we read them */

	if(typedef_name) {
		printf("typedef ");
	}
	printf("enum ");
	if(enum_name) {
		printf("%s ", enum_name);
	}
	printf("{\n");
	prev=&head;
	e_cnt=0;
	while(fgets(buf, sizeof buf, stdin)) {
		unsigned i;

		/* TODO: handle condition when line is too large for input buffer */

		if(strtab_name) {
			*prev=new_entry(buf); /* worry about parsing and escaping later */
			prev=&(*prev)->next;
		}
		if(e_cnt!=0) {
			printf(",\n");
		}
		for(i=0;buf[i];i++) {
			char ch = buf[i];
			if(isalpha(ch)) {
				buf[i]=toupper(buf[i]);
			} else if(isdigit(ch)) {
				/* do nothing */
			} else if(ch=='\n' || ch=='\r') {
				buf[i]=0; /* trim newline or CR characters */
			} else {
				buf[i]='_'; /* anything "funny" is an underscore */
			}
		}
		printf("\t%s%s", prefix, buf);
		e_cnt++;
	}
	printf("\n}");
	if(typedef_name) {
		printf(" %s;\n", typedef_name);
	} else {
		printf(";\n");
	}

	if(strtab_name) {
		struct entry *curr, *old;
		unsigned i, o; /* input index and output length */
		if(strtable_static) {
			printf("static ");
		}
		printf("int %s[] = {\n", strtab_name);
		for(curr=head;curr;) {
			char buf[MAX_STRING];
			assert(curr->data!=NULL);
			for(i=0,o=0;curr->data[i];i++) {
				char ch;
				switch(ch=curr->data[i]) {
					case '\r':
					case '\n':
						break; /* swallow newline or carriage return*/
					case '\\':
						buf[o++]='\\';
						buf[o++]='\\';
						break;
					case '"':
						buf[o++]='\\';
						buf[o++]='"';
						break;
					case '\b':
						buf[o++]='\\';
						buf[o++]='b';
						break;
					case '\f':
						buf[o++]='\\';
						buf[o++]='f';
						break;
					case '\a':
						buf[o++]='\\';
						buf[o++]='a';
						break;
					case '\t':
						buf[o++]='\\';
						buf[o++]='t';
						break;
					case '\v':
						buf[o++]='\\';
						buf[o++]='v';
						break;
					default:
						if(!isprint(ch)) {
							buf[o++]='*'; /* TODO: octal encode */
						} else {
							buf[o++]=ch;
						}
				}
				assert(o<MAX_STRING);
			}
			/* use o as the output length, so no null termination */
			printf("\t\"%.*s\"", o, buf);
			if(curr->next) {
				printf(",");
			}
			printf("\n");
			old=curr;
			curr=curr->next;
			free(old->data);
			free(old);
		}
		printf("};\n");
	}

	return 0;
}