/**
 * ircd_alis.C: ALIS, based on the ratbox-services implementation.
 *
 * Copyright © 2007 Pippijn van Steenhoven / The Ermyth Team
 * Rights to this code are as documented in COPYING.
 *
 *
 * Portions of this file were derived from sources bearing the following license:
 * Copyright © 2005-2007 William Pitcock, et al.
 * The rights to this code are as documented under doc/pod/license.pod.
 *
 * Copyright © 2003-2007 Lee Hardy <leeh@leeh.co.uk>
 * Copyright © 2003-2007 ircd-ratbox development team
 *
 * $Id: ircd_alis.C,v 1.6 2007/09/16 18:54:43 pippijn Exp $
 */

#include <boost/foreach.hpp>

#include "atheme.h"
#include <ermyth/module.h>

static char const rcsid[] = "$Id: ircd_alis.C,v 1.6 2007/09/16 18:54:43 pippijn Exp $";

REGISTER_MODULE ("alis", false, "William Pitcock <nenolod -at- nenolod.net>");

#define ALIS_MAX_PARC	10
#define ALIS_MAX_MATCH	60

#define DIR_UNSET	0
#define DIR_SET		1
#define DIR_EQUAL	2

service_t *alis;
cmdvec alis_cmdtree;

static void alis_cmd_list (sourceinfo_t *si, int parc, char *parv[]);
static void alis_cmd_help (sourceinfo_t *si, int parc, char *parv[]);
static void alis_handler (sourceinfo_t *si, int parc, char *parv[]);

command_t const alis_list = { "LIST", "Lists channels matching given parameters.", AC_NONE, ALIS_MAX_PARC, alis_cmd_list };
command_t const alis_help = { "HELP", "Displays contextual help information.", AC_NONE, 1, alis_cmd_help };

struct alis_query
{
  char const *mask;
  char *topic;
  int min;
  int max;
  int show_mode;
  int show_topicwho;
  unsigned int mode;
  int mode_dir;
  int mode_key;
  int mode_limit;
  int skip;
};

bool
_modinit (module *m)
{
  alis = add_service ("ALIS", "alis", me.name, "Channel Directory", alis_handler, alis_cmdtree);

  alis_cmdtree << alis_list;
  alis_cmdtree << alis_help;

  return true;
}

void
_moddeinit ()
{
  alis_cmdtree >> alis_list;
  alis_cmdtree >> alis_help;

  del_service (alis);
}

static int
alis_parse_mode (char const * const txt, int *key, int *limit)
{
  int mode = 0;
  char const *text = txt;

  if (!text)
    return 0;

  while (*text)
    {
      switch (*text)
	{
	case 'l':
	  *limit = 1;
	  break;
	case 'k':
	  *key = 1;
	  break;
	default:
	  mode |= mode_to_flag (*text);
	  break;
	}

      text++;
    }

  return mode;
}

static int
parse_alis (sourceinfo_t *si, int parc, char *parv[], struct alis_query *query)
{
  int i = 0;
  char *opt = NULL, *arg = NULL;

  while ((opt = parv[i++]))
    {
      if (!strcasecmp (opt, "-min"))
	{
	  if ((arg = parv[i++]) == NULL || (query->min = atoi (arg)) < 1)
	    {
	      command_fail (si, fault::badparams, "Invalid -min option");
	      return 0;
	    }
	}
      else if (!strcasecmp (opt, "-max"))
	{
	  if ((arg = parv[i++]) == NULL || (query->max = atoi (arg)) < 1)
	    {
	      command_fail (si, fault::badparams, "Invalid -max option");
	      return 0;
	    }
	}
      else if (!strcasecmp (opt, "-skip"))
	{
	  if ((arg = parv[i++]) == NULL || (query->skip = atoi (arg)) < 1)
	    {
	      command_fail (si, fault::badparams, "Invalid -skip option");
	      return 0;
	    }
	}
      else if (!strcasecmp (opt, "-topic"))
	{
	  query->topic = strtok (NULL, " ");
	}
      else if (!strcasecmp (opt, "-show"))
	{
	  arg = parv[i++];

	  if (arg == NULL)
	    {
	      command_fail (si, fault::badparams, "Invalid -show option");
	      return 0;
	    }

	  if (arg[0] == 'm')
	    {
	      query->show_mode = 1;

	      if (arg[1] == 't')
		query->show_topicwho = 1;
	    }
	  else if (arg[0] == 't')
	    {
	      query->show_topicwho = 1;

	      if (arg[1] == 'm')
		query->show_mode = 1;
	    }
	}
      else if (!strcasecmp (opt, "-mode"))
	{
	  arg = parv[i++];

	  if (arg == NULL)
	    {
	      command_fail (si, fault::badparams, "Invalid -mode option");
	      return 0;
	    }

	  switch (*arg)
	    {
	    case '+':
	      query->mode_dir = DIR_SET;
	      break;
	    case '-':
	      query->mode_dir = DIR_UNSET;
	      break;
	    case '=':
	      query->mode_dir = DIR_EQUAL;
	      break;
	    default:
	      command_fail (si, fault::badparams, "Invalid -mode option");
	      return 0;
	    }

	  query->mode = alis_parse_mode (arg + 1, &query->mode_key, &query->mode_limit);

	  if (query->mode == 0)
	    {
	      command_fail (si, fault::badparams, "Invalid -mode option");
	      return 0;
	    }
	}
      else
	{
	  command_fail (si, fault::badparams, "Invalid option %s", opt);
	  return 0;
	}
    }

  return 1;
}

static void
print_channel (sourceinfo_t *si, channel_t *c, struct alis_query *query)
{
  int show_topicwho = query->show_topicwho;
  int show_topic = 1;
  char modestr[MAXEXTMODES + 60];
  int i, j;

  /* cant show a topicwho, when a channel has no topic. */
  if (!c->topic)
    {
      show_topicwho = 0;
      show_topic = 0;
    }
  if (query->show_mode)
    {
      j = 0;
      modestr[j++] = '+';
      for (i = 0; i < MAXEXTMODES; i++)
	if (c->extmodes[i] != NULL)
	  modestr[j++] = ignore_mode_list[i].mode;
      if (c->limit != 0)
	modestr[j++] = 'l';
      if (c->key != NULL)
	modestr[j++] = 'k';
      modestr[j] = '\0';
      strlcat (modestr, flags_to_string (c->modes), sizeof modestr);
    }

  if (query->show_mode && show_topicwho && show_topic)
    command_success_nodata (si, "%-50s %-8s %3ld :%s (%s)", c->name, modestr, LIST_LENGTH (&c->members), c->topic, c->topic_setter);
  else if (query->show_mode)
    command_success_nodata (si, "%-50s %-8s %3ld :%s", c->name, modestr, LIST_LENGTH (&c->members), c->topic);
  else if (show_topicwho && show_topic)
    command_success_nodata (si, "%-50s %3ld :%s (%s)", c->name, LIST_LENGTH (&c->members), c->topic, c->topic_setter);
  else if (show_topic)
    command_success_nodata (si, "%-50s %3ld :%s", c->name, LIST_LENGTH (&c->members), c->topic);
  else
    command_success_nodata (si, "%-50s %3ld", c->name, LIST_LENGTH (&c->members));
}

static int
show_channel (channel_t *c, struct alis_query *query)
{
  /* skip +s channels */
  if (c->modes & CMODE_SEC)
    return 0;

  if ((int) LIST_LENGTH (&c->members) < query->min || (query->max && (int) LIST_LENGTH (&c->members) > query->max))
    return 0;

  if (query->mode)
    {
      if (query->mode_dir == DIR_SET)
	{
	  if (((c->modes & query->mode) == 0) || (query->mode_key && c->key[0] == '\0') || (query->mode_limit && !c->limit))
	    return 0;
	}
      else if (query->mode_dir == DIR_UNSET)
	{
	  if ((c->modes & query->mode) || (query->mode_key && c->key[0] != '\0') || (query->mode_limit && c->limit))
	    return 0;
	}
      else if (query->mode_dir == DIR_EQUAL)
	{
	  if ((c->modes != query->mode) || (query->mode_key && c->key[0] == '\0') || (query->mode_limit && !c->limit))
	    return 0;
	}
    }

  if (match (query->mask, c->name))
    return 0;

  if (query->topic != NULL && match (query->topic, c->topic))
    return 0;

  if (query->skip)
    {
      query->skip--;
      return 0;
    }

  return 1;
}

static void
alis_cmd_list (sourceinfo_t *si, int parc, char *parv[])
{
  channel_t *c;
  struct alis_query query;
  int maxmatch = ALIS_MAX_MATCH;

  memset (&query, 0, sizeof (struct alis_query));

  query.mask = parc >= 1 ? parv[0] : "*";
  if (!parse_alis (si, parc - 1, parv + 1, &query))
    return;

  logcommand (si, CMDLOG_GET, "LIST %s", query.mask);

  command_success_nodata (si, "Returning maximum of %d channel names matching '\2%s\2'", ALIS_MAX_MATCH, query.mask);

  /* hunting for one channel.. */
  if (strchr (query.mask, '*') == NULL && strchr (query.mask, '?') == NULL)
    {
      if ((c = channel_find (query.mask)) != NULL)
	{
	  if (!(c->modes & CMODE_SEC))
	    print_channel (si, c, &query);
	}

      command_success_nodata (si, "End of output");
      return;
    }

  foreach (channel_pair &cp, chanlist)
    {
      c = cp.second;
      /* matches, so show it */
      if (show_channel (c, &query))
        {
          print_channel (si, c, &query);
          
          if (--maxmatch == 0)
            {
              command_success_nodata (si, "Maximum channel output reached");
              break;
            }
        }
    }

  command_success_nodata (si, "End of output");
  return;
}

static void
alis_cmd_help (sourceinfo_t *si, int parc, char *parv[])
{
  command_help (si, alis_cmdtree);
}

static void
alis_handler (sourceinfo_t *si, int parc, char *parv[])
{
  char orig[BUFSIZE];
  char *cmd;
  char *text;

  /* this should never happen */
  if (parv[0][0] == '&')
    {
      slog (LG_ERROR, "services(): got parv with local channel: %s", parv[0]);
      return;
    }

  /* make a copy of the original for debugging */
  strlcpy (orig, parv[parc - 1], BUFSIZE);

  /* lets go through this to get the command */
  cmd = strtok (parv[parc - 1], " ");
  text = strtok (NULL, "");

  if (!cmd)
    return;
  if (*cmd == '\001')
    {
      handle_ctcp_common (si, cmd, text);
      return;
    }

  /* take the command through the hash table */
  command_exec_split (alis, si, cmd, text, alis_cmdtree);
}