/* This program reads in an xbase-dbf file and sends 'inserts' to an
   PostgreSQL-server with the records in the xbase-file

   M. Boekhold (maarten.boekhold@reuters.com)  okt. 1995
   oktober 1996: merged sources of dbf2msql.c and dbf2pg.c
   oktober 1997: removed msql support
*/
#include "postgres_fe.h"

#include <fcntl.h>
#include <unistd.h>
#include <ctype.h>
#ifdef HAVE_TERMIOS_H
#include <termios.h>
#endif
#ifdef HAVE_ICONV_H
#include <iconv.h>
#endif
#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif

#include "libpq-fe.h"
#include "dbf.h"

int			verbose = 0,
			upper = 0,
			lower = 0,
			create = 0,
			fieldlow = 0;
int			del = 0;
unsigned int begin = 0,
			end = 0;
unsigned int t_block = 0;

#ifdef HAVE_ICONV_H
char	   *charset_from = NULL;
char	   *charset_to = "ISO-8859-1";
iconv_t		iconv_d;
char		convert_charset_buff[8192];
#endif

char	   *host = NULL;
char	   *dbase = "test";
char	   *table = "test";
char	   *username = NULL;
char	   *password = NULL;
char	   *subarg = NULL;
char		escape_buff[8192];

void		do_substitute(char *subarg, dbhead * dbh);

static inline void strtoupper(char *string);
static inline void strtolower(char *string);

void		do_create(PGconn *, char *, dbhead *);
void		do_inserts(PGconn *, char *, dbhead *);
int			check_table(PGconn *, char *);

char	   *Escape_db(char *);

#ifdef HAVE_ICONV_H
char	   *convert_charset(char *string);
#endif
void		usage(void);


static inline void
strtoupper(char *string)
{
	while (*string != '\0')
	{
		*string = toupper((unsigned char) *string);
		string++;
	}
}

static inline void
strtolower(char *string)
{
	while (*string != '\0')
	{
		*string = tolower((unsigned char) *string);
		string++;
	}
}

/* FIXME: should this check for overflow? */
char *
Escape_db(char *string)
{
	char	   *foo,
			   *bar;

	foo = escape_buff;

	bar = string;
	while (*bar != '\0')
	{
		if ((*bar == '\t') ||
			(*bar == '\n') ||
			(*bar == '\\'))
			*foo++ = '\\';
		*foo++ = *bar++;
	}
	*foo = '\0';

	return escape_buff;
}

#ifdef HAVE_ICONV_H
char *
convert_charset(char *string)
{
	size_t		in_size,
				out_size,
				nconv;
	char	   *in_ptr,
			   *out_ptr;

	in_size = strlen(string) + 1;
	out_size = sizeof(convert_charset_buff);
	in_ptr = string;
	out_ptr = convert_charset_buff;

	iconv(iconv_d, NULL, &in_size, &out_ptr, &out_size);		/* necessary to reset
																 * state information */
	while (in_size > 0)
	{
		nconv = iconv(iconv_d, &in_ptr, &in_size, &out_ptr, &out_size);
		if (nconv == (size_t) -1)
		{
			printf("WARNING: cannot convert charset of string \"%s\".\n",
				   string);
			strcpy(convert_charset_buff, string);
			return convert_charset_buff;
		}
	}
	*out_ptr = 0;				/* terminate output string */
	return convert_charset_buff;
}
#endif

int
check_table(PGconn *conn, char *table)
{
	char	   *q = "select relname from pg_class where "
	"relkind='r' and relname !~* '^pg'";
	PGresult   *res;
	int			i = 0;

	if (!(res = PQexec(conn, q)))
	{
		printf("%s\n", PQerrorMessage(conn));
		return 0;
	}

	for (i = 0; i < PQntuples(res); i++)
	{
		if (!strcmp(table, PQgetvalue(res, i, PQfnumber(res, "relname"))))
			return 1;
	}

	return 0;
}

void
usage(void)
{
	printf("dbf2pg\n"
		   "usage: dbf2pg [-u | -l] [-h hostname] [-W] [-U username]\n"
	"              [-B transaction_size] [-F charset_from [-T charset_to]]\n"
		   "              [-s oldname=[newname][,oldname=[newname][...]]] [-d dbase]\n"
		   "              [-t table] [-c | -D] [-f] [-v[v]] dbf-file\n");
}

/* patch submitted by Jeffrey Y. Sue <jysue@aloha.net> */
/* Provides functionality for substituting dBase-fieldnames for others */
/* Mainly for avoiding conflicts between fieldnames and SQL-reserved */
/* keywords */

void
do_substitute(char *subarg, dbhead * dbh)
{
	/* NOTE: subarg is modified in this function */
	int			i,
				bad;
	char	   *p,
			   *oldname,
			   *newname;

	if (!subarg)
		return;
	if (verbose > 1)
		printf("Substituting new field names\n");
	/* use strstr instead of strtok because of possible empty tokens */
	oldname = subarg;
	while (oldname && strlen(oldname) && (p = strstr(oldname, "=")))
	{
		*p = '\0';				/* mark end of oldname */
		newname = ++p;			/* point past \0 of oldname */
		if (strlen(newname))
		{						/* if not an empty string */
			p = strstr(newname, ",");
			if (p)
			{
				*p = '\0';		/* mark end of newname */
				p++;			/* point past where the comma was */
			}
		}
		if (strlen(newname) >= DBF_NAMELEN)
		{
			printf("Truncating new field name %s to %d chars\n",
				   newname, DBF_NAMELEN - 1);
			newname[DBF_NAMELEN - 1] = '\0';
		}
		bad = 1;
		for (i = 0; i < dbh->db_nfields; i++)
		{
			if (strcmp(dbh->db_fields[i].db_name, oldname) == 0)
			{
				bad = 0;
				strcpy(dbh->db_fields[i].db_name, newname);
				if (verbose > 1)
				{
					printf("Substitute old:%s new:%s\n",
						   oldname, newname);
				}
				break;
			}
		}
		if (bad)
		{
			printf("Warning: old field name %s not found\n",
				   oldname);
		}
		oldname = p;
	}
}	/* do_substitute */

void
do_create(PGconn *conn, char *table, dbhead * dbh)
{
	char	   *query;
	char		t[20];
	int			i,
				length;
	PGresult   *res;

	if (verbose > 1)
		printf("Building CREATE-clause\n");

	if (!(query = (char *) malloc(
							   (dbh->db_nfields * 40) + 29 + strlen(table))))
	{
		fprintf(stderr, "Memory allocation error in function do_create\n");
		PQfinish(conn);
		close(dbh->db_fd);
		free(dbh);
		exit(1);
	}

	sprintf(query, "CREATE TABLE %s (", table);
	length = strlen(query);
	for (i = 0; i < dbh->db_nfields; i++)
	{
		if (!strlen(dbh->db_fields[i].db_name))
		{
			continue;
			/* skip field if length of name == 0 */
		}
		if ((strlen(query) != length))
			strcat(query, ",");

		if (fieldlow)
			strtolower(dbh->db_fields[i].db_name);

		strcat(query, dbh->db_fields[i].db_name);
		switch (dbh->db_fields[i].db_type)
		{
			case 'D':
				strcat(query, " date");
				break;
			case 'C':
				if (dbh->db_fields[i].db_flen > 1)
				{
					strcat(query, " varchar");
					snprintf(t, 20, "(%d)",
							 dbh->db_fields[i].db_flen);
					strcat(query, t);
				}
				else
					strcat(query, " char");
				break;
			case 'N':
				if (dbh->db_fields[i].db_dec != 0)
					strcat(query, " real");
				else
					strcat(query, " int");
				break;
			case 'L':
				strcat(query, " char");
				break;
			case 'M':
				strcat(query, " text");
				break;
		}
	}

	strcat(query, ")");

	if (verbose > 1)
	{
		printf("Sending create-clause\n");
		printf("%s\n", query);
	}

	if ((res = PQexec(conn, query)) == NULL ||
		PQresultStatus(res) != PGRES_COMMAND_OK)
	{
		fprintf(stderr, "Error creating table!\n");
		fprintf(stderr, "Detailed report: %s\n", PQerrorMessage(conn));
		close(dbh->db_fd);
		free(dbh);
		free(query);
		PQfinish(conn);
		exit(1);
	}

	PQclear(res);
	free(query);
}

/* FIXME: can be optimized to not use strcat, but it is worth the effort? */
void
do_inserts(PGconn *conn, char *table, dbhead * dbh)
{
	PGresult   *res;
	field	   *fields;
	int			i,
				h,
				j,
				result;
	char	   *query,
			   *foo;
	char		pgdate[11];

	if (verbose > 1)
		printf("Inserting records\n");

	h = 2;						/* 2 because of terminating \n\0 */

	for (i = 0; i < dbh->db_nfields; i++)
	{
		h += dbh->db_fields[i].db_flen > 2 ?
			dbh->db_fields[i].db_flen :
			2;					/* account for possible NULL values (\N) */
		h += 1;					/* the delimiter */
	}

	/*
	 * make sure we can build the COPY query, note that we don't need to just
	 * add this value, since the COPY query is a separate query (see below)
	 */
	if (h < 17 + strlen(table))
		h = 17 + strlen(table);

	if (!(query = (char *) malloc(h)))
	{
		PQfinish(conn);
		fprintf(stderr,
				"Memory allocation error in function do_inserts (query)\n");
		close(dbh->db_fd);
		free(dbh);
		exit(1);
	}

	if ((fields = dbf_build_record(dbh)) == (field *) DBF_ERROR)
	{
		fprintf(stderr,
				"Couldn't allocate memory for record in do_insert\n");
		PQfinish(conn);
		free(query);
		dbf_close(dbh);
		exit(1);
	}

	if (end == 0)				/* "end" is a user option, if not specified, */
		end = dbh->db_records;	/* then all records are processed. */

	if (t_block == 0)			/* user not specified transaction block size */
		t_block = end - begin;	/* then we set it to be the full data */

	for (i = begin; i < end; i++)
	{
		/* we need to start a new transaction and COPY statement */
		if (((i - begin) % t_block) == 0)
		{
			if (verbose > 1)
				fprintf(stderr, "Transaction: START\n");
			res = PQexec(conn, "BEGIN");
			if (res == NULL)
			{
				fprintf(stderr, "Error starting transaction!\n");
				fprintf(stderr, "Detailed report: %s\n", PQerrorMessage(conn));
				exit(1);
			}
			sprintf(query, "COPY %s FROM stdin", table);
			res = PQexec(conn, query);
			if (res == NULL)
			{
				fprintf(stderr, "Error starting COPY!\n");
				fprintf(stderr, "Detailed report: %s\n", PQerrorMessage(conn));
				exit(1);
			}
		}

		/* build line and submit */
		result = dbf_get_record(dbh, fields, i);
		if (result == DBF_VALID)
		{
			query[0] = '\0';
			j = 0;				/* counter for fields in the output */
			for (h = 0; h < dbh->db_nfields; h++)
			{
				if (!strlen(fields[h].db_name)) /* When the new fieldname is
												 * empty, the field is skipped */
					continue;
				else
					j++;

				if (j > 1)		/* not for the first field! */
					strcat(query, "\t");		/* COPY statement field
												 * separator */

				if (upper)
					strtoupper((char *) fields[h].db_contents);
				if (lower)
					strtolower((char *) fields[h].db_contents);

				foo = (char *) fields[h].db_contents;
#ifdef HAVE_ICONV_H
				if (charset_from)
					foo = convert_charset(foo);
#endif
				foo = Escape_db(foo);

				/* handle the date first - liuk */
				if (fields[h].db_type == 'D')
				{
					if (strlen(foo) == 0)
					{
						/* assume empty string means a NULL */
						strcat(query, "\\N");
					}
					else if (strlen(foo) == 8 &&
							 strspn(foo, "0123456789") == 8)
					{
						/* transform YYYYMMDD to Postgres style */
						snprintf(pgdate, 11, "%c%c%c%c-%c%c-%c%c",
								 foo[0], foo[1], foo[2], foo[3],
								 foo[4], foo[5], foo[6], foo[7]);
						strcat(query, pgdate);
					}
					else
					{
						/* try to insert it as-is */
						strcat(query, foo);
					}
				}
				else if (fields[h].db_type == 'N')
				{
					if (strlen(foo) == 0)
					{
						/* assume empty string means a NULL */
						strcat(query, "\\N");
					}
					else
						strcat(query, foo);
				}
				else
				{
					strcat(query, foo); /* must be character */
				}
			}
			strcat(query, "\n");

			if ((verbose > 1) && ((i % 100) == 0))
			{					/* Only show every 100 */
				printf("Inserting record %d\n", i);		/* records. */
			}
			PQputline(conn, query);

		}
		/* we need to end this copy and transaction */
		if (((i - begin) % t_block) == t_block - 1)
		{
			if (verbose > 1)
				fprintf(stderr, "Transaction: END\n");
			PQputline(conn, "\\.\n");
			if (PQendcopy(conn) != 0)
			{
				fprintf(stderr, "Something went wrong while copying. Check "
						"your tables!\n");
				exit(1);
			}
			res = PQexec(conn, "END");
			if (res == NULL)
			{
				fprintf(stderr, "Error committing work!\n");
				fprintf(stderr, "Detailed report: %s\n", PQerrorMessage(conn));
				exit(1);
			}
		}
	}

	/* last row copied in, end copy and transaction */
	/* remember, i is now 1 greater then when we left the loop */
	if (((i - begin) % t_block) != 0)
	{
		if (verbose > 1)
			fprintf(stderr, "Transaction: END\n");
		PQputline(conn, "\\.\n");

		if (PQendcopy(conn) != 0)
		{
			fprintf(stderr, "Something went wrong while copying. Check "
					"your tables!\n");
		}
		res = PQexec(conn, "END");
		if (res == NULL)
		{
			fprintf(stderr, "Error committing work!\n");
			fprintf(stderr, "Detailed report: %s\n", PQerrorMessage(conn));
			exit(1);
		}
	}
	dbf_free_record(dbh, fields);

	free(query);
}


int
main(int argc, char **argv)
{
	PGconn	   *conn;
	int			i;
	extern int	optind;
	extern char *optarg;
	char	   *query;
	dbhead	   *dbh;

	while ((i = getopt(argc, argv, "DWflucvh:b:e:d:t:s:B:U:F:T:")) != -1)
	{
		switch (i)
		{
			case 'D':
				if (create)
				{
					usage();
					printf("Can't use -c and -D at the same time!\n");
					exit(1);
				}
				del = 1;
				break;
			case 'W':
				password = simple_prompt("Password: ", 100, 0);
				break;
			case 'f':
				fieldlow = 1;
				break;
			case 'v':
				verbose++;
				break;
			case 'c':
				if (del)
				{
					usage();
					printf("Can't use -c and -D at the same time!\n");
					exit(1);
				}
				create = 1;
				break;
			case 'l':
				lower = 1;
				break;
			case 'u':
				if (lower)
				{
					usage();
					printf("Can't use -u and -l at the same time!\n");
					exit(1);
				}
				upper = 1;
				break;
			case 'b':
				begin = atoi(optarg);
				break;
			case 'e':
				end = atoi(optarg);
				break;
			case 'h':
				host = (char *) strdup(optarg);
				break;
			case 'd':
				dbase = (char *) strdup(optarg);
				break;
			case 't':
				table = (char *) strdup(optarg);
				break;
			case 's':
				subarg = (char *) strdup(optarg);
				break;
			case 'B':
				t_block = atoi(optarg);
				break;
			case 'U':
				username = (char *) strdup(optarg);
				break;
			case 'F':
#ifdef HAVE_ICONV_H
				charset_from = (char *) strdup(optarg);
#else
				printf("WARNING: dbf2pg was compiled without iconv support, ignoring -F option\n");
#endif
				break;
#ifdef HAVE_ICONV_H
			case 'T':
				charset_to = (char *) strdup(optarg);
				break;
#endif
			case ':':
				usage();
				printf("missing argument!\n");
				exit(1);
				break;
			case '?':
				usage();

				/*
				 * FIXME: Ivan thinks this is bad: printf("unknown argument:
				 * %s\n", argv[0]);
				 */
				exit(1);
				break;
			default:
				break;
		}
	}

	argc -= optind;
	argv = &argv[optind];

	if (argc != 1)
	{
		usage();
		if (username)
			free(username);
		if (password)
			free(password);
		exit(1);
	}

#ifdef HAVE_ICONV_H
	if (charset_from)
	{
		if (verbose > 1)
			printf("Setting conversion from charset \"%s\" to \"%s\".\n",
				   charset_from, charset_to);
		iconv_d = iconv_open(charset_to, charset_from);
		if (iconv_d == (iconv_t) - 1)
		{
			printf("Cannot convert from charset \"%s\" to charset \"%s\".\n",
				   charset_from, charset_to);
			exit(1);
		}
	}
#endif

	if (verbose > 1)
		printf("Opening dbf-file\n");

	setlocale(LC_ALL, "");		/* fix for isprint() */

	if ((dbh = dbf_open(argv[0], O_RDONLY)) == (dbhead *) - 1)
	{
		fprintf(stderr, "Couldn't open xbase-file %s\n", argv[0]);
		if (username)
			free(username);
		if (password)
			free(password);
#ifdef HAVE_ICONV_H
		if (charset_from)
			iconv_close(iconv_d);
#endif
		exit(1);
	}

	if (fieldlow)
		for (i = 0; i < dbh->db_nfields; i++)
			strtolower(dbh->db_fields[i].db_name);

	if (verbose)
	{
		printf("dbf-file: %s, PG-dbase: %s, PG-table: %s\n", argv[0],
			   dbase,
			   table);
		printf("Number of records: %ld\n", dbh->db_records);
		printf("NAME:\t\tLENGTH:\t\tTYPE:\n");
		printf("-------------------------------------\n");
		for (i = 0; i < dbh->db_nfields; i++)
		{
			printf("%-12s\t%7d\t\t%5c\n", dbh->db_fields[i].db_name,
				   dbh->db_fields[i].db_flen,
				   dbh->db_fields[i].db_type);
		}
	}

	if (verbose > 1)
		printf("Making connection to PG-server\n");

	conn = PQsetdbLogin(host, NULL, NULL, NULL, dbase, username, password);
	if (PQstatus(conn) != CONNECTION_OK)
	{
		fprintf(stderr, "Couldn't get a connection with the ");
		fprintf(stderr, "designated host!\n");
		fprintf(stderr, "Detailed report: %s\n", PQerrorMessage(conn));
		close(dbh->db_fd);
		free(dbh);
		if (username)
			free(username);
		if (password)
			free(password);
#ifdef HAVE_ICONV_H
		if (charset_from)
			iconv_close(iconv_d);
#endif
		exit(1);
	}

	PQexec(conn, "SET search_path = public");

/* Substitute field names */
	do_substitute(subarg, dbh);

/* create table if specified, else check if target table exists */
	if (!create)
	{
		if (!check_table(conn, table))
		{
			printf("Table does not exist!\n");
			if (username)
				free(username);
			if (password)
				free(password);
#ifdef HAVE_ICONV_H
			if (charset_from)
				iconv_close(iconv_d);
#endif
			exit(1);
		}
		if (del)
		{
			if (!(query = (char *) malloc(13 + strlen(table))))
			{
				printf("Memory-allocation error in main (delete)!\n");
				close(dbh->db_fd);
				free(dbh);
				PQfinish(conn);
				if (username)
					free(username);
				if (password)
					free(password);
#ifdef HAVE_ICONV_H
				if (charset_from)
					iconv_close(iconv_d);
#endif
				exit(1);
			}
			if (verbose > 1)
				printf("Deleting from original table\n");
			sprintf(query, "DELETE FROM %s", table);
			PQexec(conn, query);
			free(query);
		}
	}
	else
	{
		if (!(query = (char *) malloc(12 + strlen(table))))
		{
			printf("Memory-allocation error in main (drop)!\n");
			close(dbh->db_fd);
			free(dbh);
			PQfinish(conn);
			if (username)
				free(username);
			if (password)
				free(password);
#ifdef HAVE_ICONV_H
			if (charset_from)
				iconv_close(iconv_d);
#endif
			exit(1);
		}
		if (verbose > 1)
			printf("Dropping original table (if one exists)\n");
		sprintf(query, "DROP TABLE %s", table);
		PQexec(conn, query);
		free(query);

/* Build a CREATE-clause
*/
		do_create(conn, table, dbh);
	}

/* Build an INSERT-clause
*/
	PQexec(conn, "SET DATESTYLE TO 'ISO';");
	do_inserts(conn, table, dbh);

	if (verbose > 1)
		printf("Closing up....\n");

	close(dbh->db_fd);
	free(dbh);
	PQfinish(conn);
	if (username)
		free(username);
	if (password)
		free(password);
#ifdef HAVE_ICONV_H
	if (charset_from)
		iconv_close(iconv_d);
#endif
	exit(0);
}