/*
 * This file is distributed as part of MaxScale.  It is free
 * software: you can redistribute it and/or modify it under the terms of the
 * GNU General Public License as published by the Free Software Foundation,
 * version 2.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Copyright MariaDB Corporation Ab 2014
 */

/**
 * @file maxadmin.c  - The MaxScale administration client
 *
 * @verbatim
 * Revision History
 *
 * Date		Who		Description
 * 13/06/14	Mark Riddoch	Initial implementation
 * 15/06/14	Mark Riddoch	Addition of source command
 * 26/06/14	Mark Riddoch	Fix issue with final OK split across
 *				multiple reads
 *
 * @endverbatim
 */

#include <stdio.h>
#include <string.h>
#include <signal.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <ctype.h>
#include <stdlib.h>
#include <termios.h>
#include <unistd.h>
#include <dirent.h>
#include <locale.h>
#include <errno.h>
#include <getopt.h>

#include <version.h>

#ifdef HISTORY
#include <histedit.h>
#endif

static int connectMaxScale(char *hostname, char *port);
static int setipaddress(struct in_addr *a, char *p);
static int authMaxScale(int so, char *user, char *password);
static int sendCommand(int so, char *cmd);
static void DoSource(int so, char *cmd);
static void DoUsage();
static int isquit(char *buf);
static void PrintVersion(const char *progname);
static void read_inifile(char **hostname, char **port, char **user, char **passwd);

#ifdef HISTORY
static char *
prompt(EditLine *el __attribute__((__unused__)))
{
	static char prompt[] = "MaxScale> ";

	return prompt;
}
#endif

static struct option long_options[] = {
  {"host",     required_argument, 0, 'h'},
  {"user",     required_argument, 0, 'u'},
  {"password", required_argument, 0, 'p'},
  {"port",     required_argument, 0, 'P'},
  {"version",  no_argument,       0, 'v'},
  {"help",     no_argument,       0, '?'},
  {0, 0, 0, 0}
};

/**
 * The main for the maxadmin client
 *
 * @param argc	Number of arguments
 * @param argv	The command line arguments
 */
int
main(int argc, char **argv)
{
int		i, num, rv;
#ifdef HISTORY
char		*buf;
EditLine	*el = NULL;
Tokenizer	*tok;
History		*hist;
HistEvent	ev;
const LineInfo	*li;
#else
char		buf[1024];
#endif
char		*hostname = "localhost";
char		*port = "6603";
char		*user = "admin";
char		*passwd = NULL;
int		so;
int             option_index = 0;
char            c;

	read_inifile(&hostname, &port, &user, &passwd);

        while ((c = getopt_long(argc, argv, "h:p:P:u:v?", 
				long_options, &option_index))
	       >= 0)
        {
	  switch (c) {
	  case 'h':
	    hostname = strdup(optarg);
	    break;
	  case 'p':
	    passwd = strdup(optarg);
	    break;
	  case 'P':
	    port = strdup(optarg);
	    break;
	  case 'u':
	    user = strdup(optarg);
	    break;
	  case 'v':
	    PrintVersion(*argv);
	    exit(EXIT_SUCCESS);
	  case '?':
	    DoUsage(*argv);
	    exit(optopt ? EXIT_FAILURE : EXIT_SUCCESS);
	  }	  
	}

	if (passwd == NULL)
	{
		struct termios tty_attr;
		tcflag_t c_lflag;
	
		if (tcgetattr(STDIN_FILENO, &tty_attr) < 0)
			return -1;

		c_lflag = tty_attr.c_lflag;
		tty_attr.c_lflag &= ~ICANON;
		tty_attr.c_lflag &= ~ECHO;

		if (tcsetattr(STDIN_FILENO, 0, &tty_attr) < 0)
			return -1;

		printf("Password: ");
		passwd = malloc(80);
		fgets(passwd, 80, stdin);

		tty_attr.c_lflag = c_lflag;
		if (tcsetattr(STDIN_FILENO, 0, &tty_attr) < 0)
			return -1;
		i = strlen(passwd);
		if (i > 1)
			passwd[i - 1] = '\0';
		printf("\n");
	}

	if ((so = connectMaxScale(hostname, port)) == -1)
		exit(1);
	if (!authMaxScale(so, user, passwd))
	{
		fprintf(stderr, "Failed to connect to MaxScale. "
				"Incorrect username or password.\n");
		exit(1);
	}

	if (optind < argc) {
	  int i, len = 0;
	  char *cmd;

	  for (i = optind; i < argc; i++) {
	    len += strlen(argv[i]) + 1;
	  }

	  cmd = malloc(len + (2 * argc));	// Allow for quotes
	  strncpy(cmd, argv[optind],len + (2 * argc));
	  for (i = optind +1; i < argc; i++)
	  {
	    strcat(cmd, " ");
	    /* Arguments after the seconf are quoted to allow for names
	     * that contain white space
	     */
	    if (i - optind > 1)
	    {
	       strcat(cmd, "\"");
	       strcat(cmd, argv[i]);
	       strcat(cmd, "\"");
	    }
	    else
	       strcat(cmd, argv[i]);
	  }

	  if (access(cmd, R_OK) == 0)
	    DoSource(so, cmd);
	  else
	    sendCommand(so, cmd);

	  free(cmd);
	  exit(0);
	}

	(void) setlocale(LC_CTYPE, "");
#ifdef HISTORY
	hist = history_init();		/* Init the builtin history	*/
					/* Remember 100 events		*/
	history(hist, &ev, H_SETSIZE, 100);

	tok  = tok_init(NULL);		/* Initialize the tokenizer	*/

					/* Initialize editline		*/
	el = el_init(*argv, stdin, stdout, stderr);

	el_set(el, EL_EDITOR, "vi");	/* Default editor is vi		*/
	el_set(el, EL_SIGNAL, 1);	/* Handle signals gracefully	*/
	el_set(el, EL_PROMPT, prompt);/* Set the prompt function */

			/* Tell editline to use this history interface	*/
	el_set(el, EL_HIST, history, hist);

	/*
	 * Bind j, k in vi command mode to previous and next line, instead
	 * of previous and next history.
	 */
	el_set(el, EL_BIND, "-a", "k", "ed-prev-line", NULL);
	el_set(el, EL_BIND, "-a", "j", "ed-next-line", NULL);

	/*
	 * Source the user's defaults file.
	 */
	el_source(el, NULL);

	while ((buf = (char *)el_gets(el, &num)) != NULL && num != 0)
	{
#else
	while (printf("MaxScale> ") && fgets(buf, 1024, stdin) != NULL)
	{
		num = strlen(buf);
#endif
		/* Strip trailing \n\r */
		for (i = num - 1; buf[i] == '\r' || buf[i] == '\n'; i--)
			buf[i] = 0;

#ifdef HISTORY
		li = el_line(el);
		history(hist, &ev, H_ENTER, buf);
#endif

		if (isquit(buf))
		{
			break;
		}
		else if (!strcasecmp(buf, "history"))
		{
#ifdef HISTORY
			for (rv = history(hist, &ev, H_LAST); rv != -1;
					rv = history(hist, &ev, H_PREV))
				fprintf(stdout, "%4d %s\n",
					    ev.num, ev.str);
#else
			fprintf(stderr, "History not supported in this version.\n");
#endif
		}
		else if (!strncasecmp(buf, "source", 6))
		{
		char *ptr;

			/* Find the filename */
			ptr = &buf[strlen("source")];
			while (*ptr && isspace(*ptr))
				ptr++;

			DoSource(so, ptr);
		}
		else if (*buf)
		{
			if (!sendCommand(so, buf))
			{
				return 0;
			}
		}
	}

#ifdef HISTORY
	el_end(el);
	tok_end(tok);
	history_end(hist);
#endif
	close(so);
	return 0;
}

/**
 * Connect to the MaxScale server
 *
 * @param hostname	The hostname to connect to
 * @param port		The port to use for the connection
 * @return		The connected socket or -1 on error
 */
static int
connectMaxScale(char *hostname, char *port)
{
struct sockaddr_in	addr;
int			so;
int			keepalive = 1;

	if ((so = socket(AF_INET, SOCK_STREAM, 0)) < 0)
	{
		fprintf(stderr, "Unable to create socket: %s\n",
				strerror(errno));
		return -1;
	}
	memset(&addr, 0, sizeof addr);
	addr.sin_family = AF_INET;
	setipaddress(&addr.sin_addr, hostname);
	addr.sin_port = htons(atoi(port));
	if (connect(so, (struct sockaddr *)&addr, sizeof(addr)) < 0)
	{
		fprintf(stderr, "Unable to connect to MaxScale at %s, %s: %s\n",
				hostname, port, strerror(errno));
		close(so);
		return -1;
	}
	if (setsockopt(so, SOL_SOCKET,
			SO_KEEPALIVE, &keepalive , sizeof(keepalive )))
		perror("setsockopt");

	return so;
}


/**
 * Set IP address in socket structure in_addr
 *
 * @param a	Pointer to a struct in_addr into which the address is written
 * @param p	The hostname to lookup
 * @return	1 on success, 0 on failure
 */
static int
setipaddress(struct in_addr *a, char *p)
{
#ifdef __USE_POSIX
	struct addrinfo *ai = NULL, hint;
	int    rc;
	struct sockaddr_in * res_addr;
	memset(&hint, 0, sizeof (hint));

	hint.ai_socktype = SOCK_STREAM;
	hint.ai_flags = AI_CANONNAME;
	hint.ai_family = AF_INET;

	if ((rc = getaddrinfo(p, NULL, &hint, &ai)) != 0) {
		return 0;
	}

        /* take the first one */
	if (ai != NULL) {
		res_addr = (struct sockaddr_in *)(ai->ai_addr);
		memcpy(a, &res_addr->sin_addr, sizeof(struct in_addr));

		freeaddrinfo(ai);

		return 1;
	}
#else
	struct hostent *h;

        spinlock_acquire(&tmplock);
        h = gethostbyname(p);
        spinlock_release(&tmplock);
        
	if (h == NULL) {
		if ((a->s_addr = inet_addr(p)) == -1) {
			return 0;
		}
	} else {
        	/* take the first one */
		memcpy(a, h->h_addr, h->h_length);

		return 1;
	}
#endif
	return 0;
}

/**
 * Perform authentication using the maxscaled protocol conventions
 *
 * @param so		The socket connected to MaxScale
 * @param user		The username to authenticate
 * @param password	The password to authenticate with
 * @return		Non-zero of succesful authentication
 */
static int
authMaxScale(int so, char *user, char *password)
{
char	buf[20];

	if (read(so, buf, 4) != 4)
		return 0;
	write(so, user, strlen(user));
	if (read(so, buf, 8) != 8)
		return 0;
	write(so, password, strlen(password));
	if (read(so, buf, 6) != 6)
		return 0;

	return strncmp(buf, "FAILED", 6);
}

/**
 * Send a comamnd using the MaxScaled protocol, display the return data
 * on standard output.
 *
 * Input terminates with a lien containing just the text OK
 *
 * @param so	The socket connect to MaxScale
 * @param cmd	The command to send
 * @return	0 if the connection was closed
 */
static int
sendCommand(int so, char *cmd)
{
char	buf[80];
int	i, j, newline = 1;

	if (write(so, cmd, strlen(cmd)) == -1)
		return 0;
	while (1)
	{
		if ((i = read(so, buf, 80)) <= 0)
			return 0;
		for (j = 0; j < i; j++)
		{
			if (newline == 1 && buf[j] == 'O')
				newline = 2;
			else if (newline == 2 && buf[j] == 'K' && j == i - 1)
			{
				return 1;
			}
			else if (newline == 2)
			{
				putchar('O');
				putchar(buf[j]);
				newline = 0;
			}
			else if (buf[j] == '\n' || buf[j] == '\r')
			{
				putchar(buf[j]);
				newline = 1;
			}
			else
			{
				putchar(buf[j]);
				newline = 0;
			}
		}
	}
	return 1;
}

/**
 * Read a file of commands and send them to MaxScale
 *
 * @param so		The socket connected to MaxScale
 * @param file		The filename
 */
static void
DoSource(int so, char *file)
{
char		*ptr, *pe;
char		line[132];
FILE		*fp;

	if ((fp = fopen(file, "r")) == NULL)
	{
		fprintf(stderr, "Unable to open command file '%s'.\n",
				file);
		return;
	}

	while ((ptr = fgets(line, 132, fp)) != NULL)
	{
		/* Strip tailing newlines */
		pe = &ptr[strlen(ptr)-1];
		while (pe >= ptr && (*pe == '\r' || *pe == '\n'))
		{
			*pe = '\0';
			pe--;
		}

		if (*ptr != '#')	/* Comment */
		{
			if (! sendCommand(so, ptr))
			{
				break;
			}
		}
	}
	fclose(fp);
	return;
}

/**
 * Print version information
 */
static void 
PrintVersion(const char *progname) 
{
        printf("%s Version %s\n", progname, MAXSCALE_VERSION);
}

/**
 * Display the --help text.
 */
static void
DoUsage(const char *progname)
{
	PrintVersion(progname);
	printf("The MaxScale administrative and monitor client.\n\n");
	printf("Usage: %s [-u user] [-p password] [-h hostname] [-P port] [<command file> | <command>]\n\n", progname);
	printf("  -u|--user=...	        The user name to use for the connection, default\n");
	printf("			is admin.\n");
	printf("  -p|--password=...	The user password, if not given the password will\n");
	printf("			be prompted for interactively\n");
	printf("  -h|--hostname=...	The maxscale host to connecto to. The default is\n");
	printf("			localhost\n");
	printf("  -P|--port=...       	The port to use for the connection, the default\n");
	printf("			port is 6603.\n");
	printf("  -v|--version          print version information and exit\n");
	printf("  -?|--help		Print this help text.\n");
	printf("Any remaining arguments are treated as MaxScale commands or a file\n");
	printf("containing commands to execute.\n");
}

/**
 * Check command to see if it is a quit command
 *
 * @param buf	The command buffer
 * @return	Non-zero if the command should cause maxadmin to quit
 */
static int
isquit(char *buf)
{
char	*ptr = buf;

	if (!buf)
		return 0;
	while (*ptr && isspace(*ptr))
		ptr++;
	if (strncasecmp(ptr, "quit", 4) == 0 || strncasecmp(ptr, "exit", 4) == 0)
		return 1;
	return 0;
}

/**
 * Trim whitespace from the right hand end of the string
 *
 * @param str	String to trim
 */
static void
rtrim(char *str)
{
char	*ptr = str + strlen(str);

	if (ptr > str)		// step back from the terminating null
		ptr--;		// If the string has more characters
	while (ptr >= str && isspace(*ptr))
		*ptr-- = 0;
}

/**
 * Read defaults for hostname, port, user and password from
 * the .maxadmin file in the users home directory.
 *
 * @param hostname	Pointer the hostname to be updated
 * @param port		Pointer to the port to be updated
 * @param user		Pointer to the user to be updated
 * @param passwd	Pointer to the password to be updated
 */
static void
read_inifile(char **hostname, char **port, char **user, char **passwd)
{
char	pathname[400];
char	*home, *brkt;
char	*name, *value;
FILE	*fp;
char	line[400];

	if ((home = getenv("HOME")) == NULL)
		return;
	snprintf(pathname, 400, "%s/.maxadmin", home);
	if ((fp = fopen(pathname, "r")) == NULL)
		return;
	while (fgets(line, 400, fp) != NULL)
	{
		rtrim(line);
		if (line[0] == 0)
			continue;
		if (line[0] == '#')
			continue;
		name = strtok_r(line, "=", &brkt);
		value = strtok_r(NULL, "=", &brkt);
		if (name && value)
		{
			if (strcmp(name, "hostname") == 0)
				*hostname = strdup(value);
			else if (strcmp(name, "port") == 0)
				*port = strdup(value);
			else if (strcmp(name, "user") == 0)
				*user = strdup(value);
			else if (strcmp(name, "passwd") == 0)
				*passwd = strdup(value);
			else
			{
				fprintf(stderr, "WARNING: Unrecognised "
					"parameter '%s' in .maxadmin file\n", name);
			}
		}
		else
		{
			fprintf(stderr, "WARNING: Expected name=value "
				"parameters in .maxadmin file but found "
				"'%s'.\n", line);
		}
	}
	fclose(fp);
}