#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include "cnames.h"

#define START -1

static int user_center = 0, user_subcenter = 0, user_ptable = 0;
static enum {filled, not_found, not_checked, no_file, init} status = init;

struct ParmTable parm_table_user[256];

/*
 * sets up user parameter table
 */

int setup_user_table(int center, int subcenter, int ptable) {

    int i, j, c0, c1, c2;
    static FILE *input;
    static int file_open = 0;
    char *filename, line[300];

    if (status == init) {
	for (i = 0; i < 256; i++) {
	    parm_table_user[i].name = parm_table_user[i].comment = NULL;
	}
	status = not_checked;
    }

    if (status == no_file) return 0;

    if ((user_center == -1 || center == user_center) &&
	    (user_subcenter == -1 || subcenter == user_subcenter) &&
	    (user_ptable == -1 || ptable == user_ptable)) {

	if (status == filled) return 1;
	if (status == not_found) return 0;
    }

    /* open gribtab file if not open */

    if (!file_open) {
        filename = getenv("GRIBTAB");
        if (filename == NULL) filename = getenv("gribtab");
        if (filename == NULL) filename = "gribtab";

        if ((input = fopen(filename,"r")) == NULL) {
            status = no_file;
            return 0;
        }
	file_open = 1;
    }
    else {
	rewind(input);
    }

    user_center = center;
    user_subcenter = subcenter;
    user_ptable = ptable;

    /* scan for center & subcenter and ptable */
    for (;;) {
        if (fgets(line, 299, input) == NULL) {
	    status = not_found;
            return 0;
        }
	if (atoi(line) != START) continue;
	i = sscanf(line,"%d:%d:%d:%d", &j, &center, &subcenter, &ptable);
        if (i != 4) {
	    fprintf(stderr,"illegal gribtab center/subcenter/ptable line: %s\n", line);
            continue;
        }
	if ((center == -1 || center == user_center) &&
	    (subcenter == -1 || subcenter == user_subcenter) &&
	    (ptable == -1 || ptable == user_ptable)) break;
    }

    user_center = center;
    user_subcenter = subcenter;
    user_ptable = ptable;

    /* free any used memory */
    if (parm_table_user[i].name != NULL) {
        for (i = 0; i < 256; i++) {
	    free(parm_table_user[i].name);
            free(parm_table_user[i].comment);
        }
    }

    /* read definitions */

    for (;;) {
        if (fgets(line, 299, input) == NULL) break;
	if ((i = atoi(line)) == START) break;
	line[299] = 0;

	/* find the colons and end-of-line */
	for (c0 = 0; line[c0] != ':' && line[c0] != 0; c0++) ;
        /* skip blank lines */
        if (line[c0] == 0) continue;

	for (c1 = c0 + 1; line[c1] != ':' && line[c1] != 0; c1++) ;
	c2 = strlen(line);
        if (line[c2-1] == '\n') line[--c2] = '\0';
        if (c2 <= c1) {
	    fprintf(stderr,"illegal gribtab line:%s\n", line);
	    continue;
	}
	line[c0] = 0;
	line[c1] = 0;

	parm_table_user[i].name = (char *) malloc(c1 - c0);
	parm_table_user[i].comment = (char *) malloc(c2 - c1);
	strcpy(parm_table_user[i].name, line+c0+1);
	strcpy(parm_table_user[i].comment, line+c1+1);
    }

    /* now to fill in undefined blanks */
    for (i = 0; i < 255; i++) {
	if (parm_table_user[i].name == NULL) {
	    parm_table_user[i].name = (char *) malloc(7);
	    sprintf(parm_table_user[i].name, "var%d", i);
	    parm_table_user[i].comment = (char *) malloc(strlen("undefined")+1);
	    strcpy(parm_table_user[i].comment, "undefined");
        }
    }
    status = filled;
    return 1;
}