/*
 *  dropnroll
 *
 *  Copyright (C) 2009-2015 Christian Pointner <equinox@spreadspace.org>
 *
 *  This file is part of dropnroll.
 *
 *  dropnroll 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, either version 3 of the License, or
 *  any later version.
 *
 *  dropnroll 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 dropnroll. If not, see <http://www.gnu.org/licenses/>.
 */

#include "datatypes.h"

#include "options.h"

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>

#include "log.h"

#define PARSE_BOOL_PARAM(SHORT, LONG, VALUE)             \
    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
      VALUE = 1;

#define PARSE_INVERSE_BOOL_PARAM(SHORT, LONG, VALUE)     \
    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
      VALUE = 0;

#define PARSE_INT_PARAM(SHORT, LONG, VALUE)              \
    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
    {                                                    \
      if(argc < 1)                                       \
        return i;                                        \
      VALUE = atoi(argv[i+1]);                           \
      argc--;                                            \
      i++;                                               \
    }

#define PARSE_STRING_PARAM(SHORT, LONG, VALUE)           \
    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
    {                                                    \
      if(argc < 1 || argv[i+1][0] == '-')                \
        return i;                                        \
      if(VALUE) free(VALUE);                             \
      VALUE = strdup(argv[i+1]);                         \
      if(!VALUE)                                         \
        return -2;                                       \
      argc--;                                            \
      i++;                                               \
    }

#define PARSE_STRING_PARAM_SEC(SHORT, LONG, VALUE)       \
    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
    {                                                    \
      if(argc < 1 || argv[i+1][0] == '-')                \
        return i;                                        \
      if(VALUE) free(VALUE);                             \
      VALUE = strdup(argv[i+1]);                         \
      if(!VALUE)                                         \
        return -2;                                       \
      size_t j;                                          \
      for(j=0; j < strlen(argv[i+1]); ++j)               \
        argv[i+1][j] = '#';                              \
      argc--;                                            \
      i++;                                               \
    }

#define PARSE_HEXSTRING_PARAM_SEC(SHORT, LONG, VALUE)    \
    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
    {                                                    \
      if(argc < 1 || argv[i+1][0] == '-')                \
        return i;                                        \
      int ret;                                           \
      ret = options_parse_hex_string(argv[i+1], &VALUE); \
      if(ret > 0)                                        \
        return i+1;                                      \
      else if(ret < 0)                                   \
        return ret;                                      \
      size_t j;                                          \
      for(j=0; j < strlen(argv[i+1]); ++j)               \
        argv[i+1][j] = '#';                              \
      argc--;                                            \
      i++;                                               \
    }

#define PARSE_STRING_LIST(SHORT, LONG, LIST)             \
    else if(!strcmp(str,SHORT) || !strcmp(str,LONG))     \
    {                                                    \
      if(argc < 1 || argv[i+1][0] == '-')                \
        return i;                                        \
      int ret = string_list_add(&LIST, argv[i+1]);       \
      if(ret == -2)                                      \
        return ret;                                      \
      else if(ret)                                       \
        return i+1;                                      \
      argc--;                                            \
      i++;                                               \
    }

int options_parse_hex_string(const char* hex, buffer_t* buffer)
{
  if(!hex || !buffer)
    return -1;

  u_int32_t hex_len = strlen(hex);
  if(hex_len%2)
    return 1;

  if(buffer->buf_)
    free(buffer->buf_);

  buffer->length_ = hex_len/2;
  buffer->buf_ = malloc(buffer->length_);
  if(!buffer->buf_) {
    buffer->length_ = 0;
    return -2;
  }

  const char* ptr = hex;
  int i;
  for(i=0;i<buffer->length_;++i) {
    u_int32_t tmp;
    sscanf(ptr, "%2X", &tmp);
    buffer->buf_[i] = (u_int8_t)tmp;
    ptr += 2;
  }

  return 0;
}



int options_parse(options_t* opt, int argc, char* argv[])
{
  if(!opt)
    return -1;

  options_default(opt);

  if(opt->progname_)
    free(opt->progname_);
  opt->progname_ = strdup(argv[0]);
  if(!opt->progname_)
    return -2;

  argc--;

  char* children_policy = NULL;
  int i;
  for(i=1; argc > 0; ++i)
  {
    char* str = argv[i];
    argc--;

    if(!strcmp(str,"-h") || !strcmp(str,"--help"))
      return -1;
    PARSE_INVERSE_BOOL_PARAM("-D","--nodaemonize", opt->daemonize_)
    PARSE_STRING_PARAM("-u","--username", opt->username_)
    PARSE_STRING_PARAM("-g","--groupname", opt->groupname_)
    PARSE_STRING_PARAM("-C","--chroot", opt->chroot_dir_)
    PARSE_STRING_PARAM("-P","--write-pid", opt->pid_file_)
    PARSE_STRING_LIST("-L","--log", opt->log_targets_)
    PARSE_BOOL_PARAM("-U", "--debug", opt->debug_)
    PARSE_STRING_PARAM("-s","--command-sock", opt->command_sock_)
    PARSE_STRING_PARAM("-x","--script", opt->script_)
    PARSE_INT_PARAM("-m","--max-children", opt->max_children_)
    PARSE_STRING_PARAM("-p","--children-policy", children_policy)
    PARSE_INT_PARAM("-r","--children-min-runtime", opt->min_child_runtime_)
    PARSE_STRING_LIST("-d","--dir", opt->dirs_)
    else
      return i;
  }

  if(opt->debug_) {
    string_list_add(&opt->log_targets_, "stdout:5");
    opt->daemonize_ = 0;
  }

  if(children_policy) {
    if(!strcmp(children_policy, "defer"))
      opt->children_policy_ = DEFER;
    else if(!strcmp(children_policy, "drop"))
      opt->children_policy_ = DROP;
    else if(!strcmp(children_policy, "kill-oldest"))
      opt->children_policy_ = KILL_OLDEST;
    else
      return -3;
  }

  if(!opt->log_targets_.first_)
    string_list_add(&opt->log_targets_, "syslog:3,dropnroll,daemon");

  if(!opt->dirs_.first_ && !opt->command_sock_)
		opt->command_sock_ = strdup("/var/run/dropnroll/cmd.sock");

  return 0;
}

int options_parse_post(options_t* opt)
{
  if(!opt)
    return -1;

  if(opt->max_children_ < 0) {
    log_printf(ERROR, "-m|--max-children invalid value %d", opt->max_children_);
    return 1;
  }

  if(opt->max_children_ == 0)
    log_printf(WARNING, "disabling child limit, this may be harmful to your system");

  return 0;
}

void options_default(options_t* opt)
{
  if(!opt)
    return;

  opt->progname_ = strdup("dropnroll");

  opt->daemonize_ = 1;
  opt->username_ = NULL;
  opt->groupname_ = NULL;
  opt->chroot_dir_ = NULL;
  opt->pid_file_ = NULL;
  string_list_init(&opt->log_targets_);
  opt->debug_ = 0;

  opt->command_sock_ = NULL;
  opt->script_ = strdup("newfile.sh");
  opt->max_children_ = 8;
  opt->children_policy_ = DEFER;
  opt->min_child_runtime_ = -1;
  string_list_init(&opt->dirs_);
}

void options_clear(options_t* opt)
{
  if(!opt)
    return;

  if(opt->progname_)
    free(opt->progname_);
  if(opt->username_)
    free(opt->username_);
  if(opt->groupname_)
    free(opt->groupname_);
  if(opt->chroot_dir_)
    free(opt->chroot_dir_);
  if(opt->pid_file_)
    free(opt->pid_file_);
  string_list_clear(&opt->log_targets_);

  if(opt->command_sock_)
    free(opt->command_sock_);
  if(opt->script_)
    free(opt->script_);
  string_list_clear(&opt->dirs_);
}

void options_print_usage()
{
  printf("USAGE:\n");
  printf("dropnroll\n");
  printf("  [-h|--help]                         prints this...\n");
  printf("  [-D|--nodaemonize]                  don't run in background\n");
  printf("  [-u|--username] <username>          change to this user\n");
  printf("  [-g|--groupname] <groupname>        change to this group\n");
  printf("  [-C|--chroot] <path>                chroot to this directory\n");
  printf("  [-P|--write-pid] <path>             write pid to this file\n");
  printf("  [-L|--log] <target>:<level>[,<param1>[,<param2>..]]\n");
  printf("                                      add a log target, can be invoked several times\n");
  printf("  [-U|--debug]                        don't daemonize and log to stdout with maximum log level\n");
  printf("  [-s|--command-sock] <unix sock>     the command socket e.g. /var/run/dropnroll/cmd.sock\n");
  printf("  [-x|--script] <script>              the command socket e.g. newfile.sh\n");
  printf("  [-m|--max-children] <#of children>  limit of children to be started e.g. 8\n");
  printf("  [-p|--children-policy] (defer|drop|kill-oldest)\n");
  printf("                                      what to do when children limit exceeds\n");
  printf("  [-r|--children-min-runtime] <secs>  in case of kill-oldest the minimum child runtime\n");
  printf("  [-d|--dir] <path>                   add a path to the watch list, can be invoked several times\n");
}

void options_print(options_t* opt)
{
  if(!opt)
    return;

  printf("progname: '%s'\n", opt->progname_);
  printf("daemonize: %d\n", opt->daemonize_);
  printf("username: '%s'\n", opt->username_);
  printf("groupname: '%s'\n", opt->groupname_);
  printf("chroot_dir: '%s'\n", opt->chroot_dir_);
  printf("pid_file: '%s'\n", opt->pid_file_);
  printf("log_targets: \n");
  string_list_print(&opt->log_targets_, "  '", "'\n");
  printf("debug: %s\n", !opt->debug_ ? "false" : "true");

  printf("command_sock: '%s'\n", opt->command_sock_);
  printf("script: '%s'\n", opt->script_);
  printf("max_children: %d\n", opt->max_children_);
  printf("children_policy: ");
  switch(opt->children_policy_) {
  case DEFER: printf("defer execution\n"); break;
  case DROP: printf("drop\n"); break;
  case KILL_OLDEST: printf("kill oldest\n"); break;
  }
  printf("min_child_runtime: %d\n", opt->min_child_runtime_);
  string_list_print(&opt->dirs_, "  '", "'\n");
}