/**********************************************************
 * MODULE:    mysql
 * AUTHOR(S): Radim Blazek (radim.blazek@gmail.com)
 * PURPOSE:   MySQL database driver
 * COPYRIGHT: (C) 2001 by the GRASS Development Team
 *            This program is free software under the 
 *            GNU General Public License (>=v2). 
 *            Read the file COPYING that comes with GRASS
 *            for details.
 **********************************************************/
#include <stdlib.h>
#include <string.h>

#include <grass/dbmi.h>
#include <grass/gis.h>
#include <grass/glocale.h>

#include "globals.h"
#include "proto.h"

int replace_variables ( char *, char **, char ** );

int db__driver_open_database(dbHandle *handle)
{
    char *name;
    dbConnection default_connection;
    MYSQL *res;

    init_error();
    db_get_connection(&default_connection);
    name = db_get_handle_dbname(handle);

    /* if name is empty use default_connection.databaseName */
    if (strlen(name) == 0) 
	name = default_connection.databaseName;

    G_debug(3, "db_driver_open_database() mysql: database definition = '%s'", name );

#ifndef MESQL
  {
    /* Client version */
    char *user, *password;
    CONNPAR connpar;

    if ( parse_conn ( name, &connpar ) == DB_FAILED ) {
	report_error();
	return DB_FAILED;
    }
    
    G_debug(3, "host = %s, port = %d, dbname = %s, "
	       "user = %s, password = %s", 
	       connpar.host, connpar.port, connpar.dbname, 
	       connpar.user, connpar.password );

    db_get_login ( "mysql", name, &user, &password );

    connection = mysql_init(NULL);
    res = mysql_real_connect ( connection, connpar.host, user, password,
	                       connpar.dbname, connpar.port, NULL, 0);

    G_free ( user );
    G_free ( password );
    
    if ( res == NULL ) 
    {
	append_error ( _("Cannot connect to MySQL: ") );
        append_error ( mysql_error(connection) );
	report_error ();
	return DB_FAILED;
    }
  }

#else

    /* Embeded version */
  {
    char *datadir, *database;
    char *server_args[4];
    char *buf;

    if ( !replace_variables ( name, &datadir, &database ) )
    {
	append_error ( _("Cannot parse MySQL embeded database name") );
        append_error ( mysql_error(connection) );
	report_error ();
	return DB_FAILED;
    }
    
    server_args[0] = "mesql"; /* this string is not used */
    G_asprintf ( &buf, "--datadir=%s", datadir ); 
    server_args[1] = buf;
    /* With InnoDB it is very slow to close the database */
    server_args[2] = "--skip-innodb"; /* OK? */
    /* Without --bootstrap it complains about missing 
     * mysql.time_zone_leap_second table */
    server_args[3] = "--bootstrap"; /* OK? */

    if ( mysql_server_init(4, server_args, NULL) )
    {
	append_error ( _("Cannot initialize MySQL embeded server") );
        append_error ( mysql_error(connection) );
	report_error ();
	free ( datadir );
	free ( database );
	return DB_FAILED;
    }

    connection = mysql_init(NULL);
    mysql_options ( connection, MYSQL_OPT_USE_EMBEDDED_CONNECTION, NULL);

    res = mysql_real_connect ( connection, NULL,NULL,NULL, database, 0,NULL,0);

    free ( datadir );
    free ( database );
    
    if ( res == NULL ) 
    {
	append_error ( _("Cannot connect to MySQL: ") );
        append_error ( mysql_error(connection) );
	report_error ();
	return DB_FAILED;
    }
  }

#endif

    return DB_OK;
}

int db__driver_close_database()
{
    init_error();
    mysql_close ( connection ); /* this will also release connection */

#ifdef MESQL
    mysql_server_end();
#endif
    
    return DB_OK;
}

int replace_variables ( char *in, char **datadir, char **database )
{
    *datadir = NULL;
    *database = NULL;

    /* parse/replace variables in input string */
    char tmp[2000];
    char **tokens;
    int no_tokens, n;

    if ( !strchr(in,'/') ) /* no path */
    {
	*datadir = G_store ( "./" );
	*database = G_store ( in );
    } 
    else
    {
	tokens = G_tokenize (in, "/");
	no_tokens = G_number_of_tokens(tokens);
    
	G_debug(3, "no_tokens = %d", no_tokens );

	tmp[0] = '\0';
	for (n = 0; n < no_tokens-1 ; n++)
	{
	   if ( n > 0 )
		strcat ( tmp, "/" );

	   G_debug (3, "tokens[%d] = %s", n, tokens[n] );
	   if ( tokens[n][0] == '$' )
	   {
	       G_strchg(tokens[n],'$', ' ' );
	       G_chop(tokens[n]);
	       strcat(tmp, G__getenv(tokens[n]) );
	       G_debug (3, "   -> %s", G__getenv(tokens[n]) );
	   }
	   else
	   {
	       strcat (tmp, tokens[n]);
	   }
	}
	*datadir = G_store ( tmp );
	*database = G_store ( tokens[n] );

	G_free_tokens ( tokens );
    }

    G_debug(2, "datadir = '%s'", *datadir );
    G_debug(2, "database = '%s'", *database );

    return 1;
}