/**
 * collectd - src/ascent.c
 * Copyright (C) 2008       Florian octo Forster
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 *
 * Authors:
 *   Florian octo Forster <octo at collectd.org>
 **/

#include "collectd.h"

#include "plugin.h"
#include "utils/common/common.h"

#include <curl/curl.h>
#include <libxml/parser.h>

static const char *races_list[] = /* {{{ */
    {
        NULL,       "Human",    /*  1 */
        "Orc",                  /*  2 */
        "Dwarf",                /*  3 */
        "Nightelf",             /*  4 */
        "Undead",               /*  5 */
        "Tauren",               /*  6 */
        "Gnome",                /*  7 */
        "Troll",                /*  8 */
        NULL,       "Bloodelf", /* 10 */
        "Draenei"               /* 11 */
};                              /* }}} */
#define RACES_LIST_LENGTH STATIC_ARRAY_SIZE(races_list)

static const char *classes_list[] = /* {{{ */
    {
        NULL,      "Warrior", /*  1 */
        "Paladin",            /*  2 */
        "Hunter",             /*  3 */
        "Rogue",              /*  4 */
        "Priest",             /*  5 */
        NULL,      "Shaman",  /*  7 */
        "Mage",               /*  8 */
        "Warlock",            /*  9 */
        NULL,      "Druid"    /* 11 */
};                            /* }}} */
#define CLASSES_LIST_LENGTH STATIC_ARRAY_SIZE(classes_list)

static const char *genders_list[] = /* {{{ */
    {"Male", "Female"};             /* }}} */
#define GENDERS_LIST_LENGTH STATIC_ARRAY_SIZE(genders_list)

struct player_stats_s {
  int races[RACES_LIST_LENGTH];
  int classes[CLASSES_LIST_LENGTH];
  int genders[GENDERS_LIST_LENGTH];
  int level_sum;
  int level_num;
  int latency_sum;
  int latency_num;
};
typedef struct player_stats_s player_stats_t;

struct player_info_s {
  int race;
  int class;
  int gender;
  int level;
  int latency;
};
typedef struct player_info_s player_info_t;
#define PLAYER_INFO_STATIC_INIT                                                \
  { -1, -1, -1, -1, -1 }

static char *url;
static char *user;
static char *pass;
static char *verify_peer;
static char *verify_host;
static char *cacert;
static char *timeout;

static CURL *curl;

static char *ascent_buffer;
static size_t ascent_buffer_size;
static size_t ascent_buffer_fill;
static char ascent_curl_error[CURL_ERROR_SIZE];

static const char *config_keys[] = {
    "URL", "User", "Password", "VerifyPeer", "VerifyHost", "CACert", "Timeout",
};
static int config_keys_num = STATIC_ARRAY_SIZE(config_keys);

static int ascent_submit_gauge(const char *plugin_instance, /* {{{ */
                               const char *type, const char *type_instance,
                               gauge_t value) {
  value_list_t vl = VALUE_LIST_INIT;

  vl.values = &(value_t){.gauge = value};
  vl.values_len = 1;
  sstrncpy(vl.plugin, "ascent", sizeof(vl.plugin));

  if (plugin_instance != NULL)
    sstrncpy(vl.plugin_instance, plugin_instance, sizeof(vl.plugin_instance));

  sstrncpy(vl.type, type, sizeof(vl.type));

  if (type_instance != NULL)
    sstrncpy(vl.type_instance, type_instance, sizeof(vl.type_instance));

  plugin_dispatch_values(&vl);
  return 0;
} /* }}} int ascent_submit_gauge */

static size_t ascent_curl_callback(void *buf, size_t size,
                                   size_t nmemb, /* {{{ */
                                   void __attribute__((unused)) * stream) {
  size_t len = size * nmemb;

  if (len == 0)
    return len;

  if ((ascent_buffer_fill + len) >= ascent_buffer_size) {
    char *temp;

    temp = realloc(ascent_buffer, ascent_buffer_fill + len + 1);
    if (temp == NULL) {
      ERROR("ascent plugin: realloc failed.");
      return 0;
    }
    ascent_buffer = temp;
    ascent_buffer_size = ascent_buffer_fill + len + 1;
  }

  memcpy(ascent_buffer + ascent_buffer_fill, (char *)buf, len);
  ascent_buffer_fill += len;
  ascent_buffer[ascent_buffer_fill] = 0;

  return len;
} /* }}} size_t ascent_curl_callback */

static int ascent_submit_players(player_stats_t *ps) /* {{{ */
{
  gauge_t value;

  for (size_t i = 0; i < RACES_LIST_LENGTH; i++)
    if (races_list[i] != NULL)
      ascent_submit_gauge("by-race", "players", races_list[i],
                          (gauge_t)ps->races[i]);

  for (size_t i = 0; i < CLASSES_LIST_LENGTH; i++)
    if (classes_list[i] != NULL)
      ascent_submit_gauge("by-class", "players", classes_list[i],
                          (gauge_t)ps->classes[i]);

  for (size_t i = 0; i < GENDERS_LIST_LENGTH; i++)
    if (genders_list[i] != NULL)
      ascent_submit_gauge("by-gender", "players", genders_list[i],
                          (gauge_t)ps->genders[i]);

  if (ps->level_num <= 0)
    value = NAN;
  else
    value = ((double)ps->level_sum) / ((double)ps->level_num);
  ascent_submit_gauge(NULL, "gauge", "avg-level", value);

  /* Latency is in ms, but we store seconds. */
  if (ps->latency_num <= 0)
    value = NAN;
  else
    value = ((double)ps->latency_sum) / (1000.0 * ((double)ps->latency_num));
  ascent_submit_gauge(NULL, "latency", "average", value);

  return 0;
} /* }}} int ascent_submit_players */

static int ascent_account_player(player_stats_t *ps, /* {{{ */
                                 player_info_t *pi) {
  if (pi->race >= 0) {
    if (((size_t)pi->race >= RACES_LIST_LENGTH) ||
        (races_list[pi->race] == NULL))
      ERROR("ascent plugin: Ignoring invalid numeric race %i.", pi->race);
    else
      ps->races[pi->race]++;
  }

  if (pi->class >= 0) {
    if (((size_t)pi->class >= CLASSES_LIST_LENGTH) ||
        (classes_list[pi->class] == NULL))
      ERROR("ascent plugin: Ignoring invalid numeric class %i.", pi->class);
    else
      ps->classes[pi->class]++;
  }

  if (pi->gender >= 0) {
    if (((size_t)pi->gender >= GENDERS_LIST_LENGTH) ||
        (genders_list[pi->gender] == NULL))
      ERROR("ascent plugin: Ignoring invalid numeric gender %i.", pi->gender);
    else
      ps->genders[pi->gender]++;
  }

  if (pi->level > 0) {
    ps->level_sum += pi->level;
    ps->level_num++;
  }

  if (pi->latency >= 0) {
    ps->latency_sum += pi->latency;
    ps->latency_num++;
  }

  return 0;
} /* }}} int ascent_account_player */

static int ascent_xml_submit_gauge(xmlDoc *doc, xmlNode *node, /* {{{ */
                                   const char *plugin_instance,
                                   const char *type,
                                   const char *type_instance) {
  char *str_ptr;
  gauge_t value;

  str_ptr = (char *)xmlNodeListGetString(doc, node->xmlChildrenNode, 1);
  if (str_ptr == NULL) {
    ERROR(
        "ascent plugin: ascent_xml_submit_gauge: xmlNodeListGetString failed.");
    return -1;
  }

  if (strcasecmp("N/A", str_ptr) == 0)
    value = NAN;
  else {
    char *end_ptr = NULL;
    value = strtod(str_ptr, &end_ptr);
    if (str_ptr == end_ptr) {
      xmlFree(str_ptr);
      ERROR("ascent plugin: ascent_xml_submit_gauge: strtod failed.");
      return -1;
    }
  }
  xmlFree(str_ptr);

  return ascent_submit_gauge(plugin_instance, type, type_instance, value);
} /* }}} int ascent_xml_submit_gauge */

static int ascent_xml_read_int(xmlDoc *doc, xmlNode *node, /* {{{ */
                               int *ret_value) {
  char *str_ptr;
  int value;

  str_ptr = (char *)xmlNodeListGetString(doc, node->xmlChildrenNode, 1);
  if (str_ptr == NULL) {
    ERROR("ascent plugin: ascent_xml_read_int: xmlNodeListGetString failed.");
    return -1;
  }

  if (strcasecmp("N/A", str_ptr) == 0)
    value = -1;
  else {
    char *end_ptr = NULL;
    value = strtol(str_ptr, &end_ptr, 0);
    if (str_ptr == end_ptr) {
      xmlFree(str_ptr);
      ERROR("ascent plugin: ascent_xml_read_int: strtol failed.");
      return -1;
    }
  }
  xmlFree(str_ptr);

  *ret_value = value;
  return 0;
} /* }}} int ascent_xml_read_int */

static int ascent_xml_sessions_plr(xmlDoc *doc, xmlNode *node, /* {{{ */
                                   player_info_t *pi) {
  for (xmlNode *child = node->xmlChildrenNode; child != NULL;
       child = child->next) {
    if ((xmlStrcmp((const xmlChar *)"comment", child->name) == 0) ||
        (xmlStrcmp((const xmlChar *)"text", child->name) == 0))
      /* ignore */;
    else if (xmlStrcmp((const xmlChar *)"race", child->name) == 0)
      ascent_xml_read_int(doc, child, &pi->race);
    else if (xmlStrcmp((const xmlChar *)"class", child->name) == 0)
      ascent_xml_read_int(doc, child, &pi->class);
    else if (xmlStrcmp((const xmlChar *)"gender", child->name) == 0)
      ascent_xml_read_int(doc, child, &pi->gender);
    else if (xmlStrcmp((const xmlChar *)"level", child->name) == 0)
      ascent_xml_read_int(doc, child, &pi->level);
    else if (xmlStrcmp((const xmlChar *)"latency", child->name) == 0)
      ascent_xml_read_int(doc, child, &pi->latency);
    else if ((xmlStrcmp((const xmlChar *)"name", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"pvprank", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"map", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"areaid", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"xpos", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"ypos", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"onime", child->name) == 0))
      /* ignore */;
    else {
      WARNING("ascent plugin: ascent_xml_status: Unknown tag: %s", child->name);
    }
  } /* for (child) */

  return 0;
} /* }}} int ascent_xml_sessions_plr */

static int ascent_xml_sessions(xmlDoc *doc, xmlNode *node) /* {{{ */
{
  player_stats_t ps = {.level_sum = 0};

  for (xmlNode *child = node->xmlChildrenNode; child != NULL;
       child = child->next) {
    if ((xmlStrcmp((const xmlChar *)"comment", child->name) == 0) ||
        (xmlStrcmp((const xmlChar *)"text", child->name) == 0))
      /* ignore */;
    else if (xmlStrcmp((const xmlChar *)"plr", child->name) == 0) {
      int status;
      player_info_t pi = PLAYER_INFO_STATIC_INIT;

      status = ascent_xml_sessions_plr(doc, child, &pi);
      if (status == 0)
        ascent_account_player(&ps, &pi);
    } else {
      WARNING("ascent plugin: ascent_xml_status: Unknown tag: %s", child->name);
    }
  } /* for (child) */

  ascent_submit_players(&ps);

  return 0;
} /* }}} int ascent_xml_sessions */

static int ascent_xml_status(xmlDoc *doc, xmlNode *node) /* {{{ */
{
  for (xmlNode *child = node->xmlChildrenNode; child != NULL;
       child = child->next) {
    if ((xmlStrcmp((const xmlChar *)"comment", child->name) == 0) ||
        (xmlStrcmp((const xmlChar *)"text", child->name) == 0))
      /* ignore */;
    else if (xmlStrcmp((const xmlChar *)"alliance", child->name) == 0)
      ascent_xml_submit_gauge(doc, child, NULL, "players", "alliance");
    else if (xmlStrcmp((const xmlChar *)"horde", child->name) == 0)
      ascent_xml_submit_gauge(doc, child, NULL, "players", "horde");
    else if (xmlStrcmp((const xmlChar *)"qplayers", child->name) == 0)
      ascent_xml_submit_gauge(doc, child, NULL, "players", "queued");
    else if ((xmlStrcmp((const xmlChar *)"acceptedconns", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"avglat", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"cdbquerysize", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"cpu", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"fthreads", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"gmcount", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"lastupdate", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"ontime", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"oplayers", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"peakcount", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"platform", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"ram", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"threads", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"uptime", child->name) == 0) ||
             (xmlStrcmp((const xmlChar *)"wdbquerysize", child->name) == 0))
      /* ignore */;
    else {
      WARNING("ascent plugin: ascent_xml_status: Unknown tag: %s", child->name);
    }
  } /* for (child) */

  return 0;
} /* }}} int ascent_xml_status */

static int ascent_xml(const char *data) /* {{{ */
{
  xmlDoc *doc;
  xmlNode *cur;

#if 0
  doc = xmlParseMemory (data, strlen (data),
      /* URL = */ "ascent.xml",
      /* encoding = */ NULL,
      /* options = */ 0);
#else
  doc = xmlParseMemory(data, strlen(data));
#endif
  if (doc == NULL) {
    ERROR("ascent plugin: xmlParseMemory failed.");
    return -1;
  }

  cur = xmlDocGetRootElement(doc);
  if (cur == NULL) {
    ERROR("ascent plugin: XML document is empty.");
    xmlFreeDoc(doc);
    return -1;
  }

  if (xmlStrcmp((const xmlChar *)"serverpage", cur->name) != 0) {
    ERROR("ascent plugin: XML root element is not \"serverpage\".");
    xmlFreeDoc(doc);
    return -1;
  }

  for (xmlNode *child = cur->xmlChildrenNode; child != NULL;
       child = child->next) {
    if ((xmlStrcmp((const xmlChar *)"comment", child->name) == 0) ||
        (xmlStrcmp((const xmlChar *)"text", child->name) == 0))
      /* ignore */;
    else if (xmlStrcmp((const xmlChar *)"status", child->name) == 0)
      ascent_xml_status(doc, child);
    else if (xmlStrcmp((const xmlChar *)"instances", child->name) == 0)
      /* ignore for now */;
    else if (xmlStrcmp((const xmlChar *)"gms", child->name) == 0)
      /* ignore for now */;
    else if (xmlStrcmp((const xmlChar *)"sessions", child->name) == 0)
      ascent_xml_sessions(doc, child);
    else {
      WARNING("ascent plugin: ascent_xml: Unknown tag: %s", child->name);
    }
  } /* for (child) */

  xmlFreeDoc(doc);
  return 0;
} /* }}} int ascent_xml */

static int config_set(char **var, const char *value) /* {{{ */
{
  if (*var != NULL) {
    free(*var);
    *var = NULL;
  }

  if ((*var = strdup(value)) == NULL)
    return 1;
  else
    return 0;
} /* }}} int config_set */

static int ascent_config(const char *key, const char *value) /* {{{ */
{
  if (strcasecmp(key, "URL") == 0)
    return config_set(&url, value);
  else if (strcasecmp(key, "User") == 0)
    return config_set(&user, value);
  else if (strcasecmp(key, "Password") == 0)
    return config_set(&pass, value);
  else if (strcasecmp(key, "VerifyPeer") == 0)
    return config_set(&verify_peer, value);
  else if (strcasecmp(key, "VerifyHost") == 0)
    return config_set(&verify_host, value);
  else if (strcasecmp(key, "CACert") == 0)
    return config_set(&cacert, value);
  else if (strcasecmp(key, "Timeout") == 0)
    return config_set(&timeout, value);
  else
    return -1;
} /* }}} int ascent_config */

static int ascent_init(void) /* {{{ */
{
  if (url == NULL) {
    WARNING("ascent plugin: ascent_init: No URL configured, "
            "returning an error.");
    return -1;
  }

  if (curl != NULL) {
    curl_easy_cleanup(curl);
  }

  if ((curl = curl_easy_init()) == NULL) {
    ERROR("ascent plugin: ascent_init: curl_easy_init failed.");
    return -1;
  }

  curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1L);
  curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, ascent_curl_callback);
  curl_easy_setopt(curl, CURLOPT_USERAGENT, COLLECTD_USERAGENT);
  curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, ascent_curl_error);

  if (user != NULL) {
#ifdef HAVE_CURLOPT_USERNAME
    curl_easy_setopt(curl, CURLOPT_USERNAME, user);
    curl_easy_setopt(curl, CURLOPT_PASSWORD, (pass == NULL) ? "" : pass);
#else
    static char credentials[1024];
    int status;

    status = ssnprintf(credentials, sizeof(credentials), "%s:%s", user,
                       (pass == NULL) ? "" : pass);
    if ((status < 0) || ((size_t)status >= sizeof(credentials))) {
      ERROR("ascent plugin: ascent_init: Returning an error because the "
            "credentials have been truncated.");
      return -1;
    }

    curl_easy_setopt(curl, CURLOPT_USERPWD, credentials);
#endif
  }

  curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
  curl_easy_setopt(curl, CURLOPT_MAXREDIRS, 50L);

  if ((verify_peer == NULL) || IS_TRUE(verify_peer))
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 1L);
  else
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);

  if ((verify_host == NULL) || IS_TRUE(verify_host))
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 2L);
  else
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);

  if (cacert != NULL)
    curl_easy_setopt(curl, CURLOPT_CAINFO, cacert);

#ifdef HAVE_CURLOPT_TIMEOUT_MS
  if (timeout != NULL)
    curl_easy_setopt(curl, CURLOPT_TIMEOUT_MS, atol(timeout));
  else
    curl_easy_setopt(curl, CURLOPT_TIMEOUT_MS,
                     (long)CDTIME_T_TO_MS(plugin_get_interval()));
#endif

  return 0;
} /* }}} int ascent_init */

static int ascent_read(void) /* {{{ */
{
  int status;

  if (curl == NULL) {
    ERROR("ascent plugin: I don't have a CURL object.");
    return -1;
  }

  if (url == NULL) {
    ERROR("ascent plugin: No URL has been configured.");
    return -1;
  }

  ascent_buffer_fill = 0;

  curl_easy_setopt(curl, CURLOPT_URL, url);

  if (curl_easy_perform(curl) != CURLE_OK) {
    ERROR("ascent plugin: curl_easy_perform failed: %s", ascent_curl_error);
    return -1;
  }

  status = ascent_xml(ascent_buffer);
  if (status != 0)
    return -1;
  else
    return 0;
} /* }}} int ascent_read */

void module_register(void) {
  plugin_register_config("ascent", ascent_config, config_keys, config_keys_num);
  plugin_register_init("ascent", ascent_init);
  plugin_register_read("ascent", ascent_read);
} /* void module_register */