/*
 *
 * Conky, a system monitor, based on torsmo
 *
 * Please see COPYING for details
 *
 * Copyright (c) 2007 Toni Spets
 * Copyright (c) 2005-2021 Brenden Matthews, Philip Kovacs, et. al.
 *	(see AUTHORS)
 * All rights reserved.
 *
 * This program 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
 * (at your option) any later version.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 *
 */

#include <assert.h>
#include <time.h>
#include <cmath>
#include <mutex>
#include "ccurl_thread.h"
#include "conky.h"
#include "logging.h"
#include "prss.h"
#include "text_object.h"

struct rss_data {
  char uri[128];
  char action[64];
  int act_par;
  float interval;
  unsigned int nrspaces;
};

namespace {
class rss_cb : public curl_callback<std::shared_ptr<PRSS>> {
  typedef curl_callback<std::shared_ptr<PRSS>> Base;

 protected:
  virtual void process_data() {
    try {
      std::shared_ptr<PRSS> tmp(new PRSS(data));

      std::unique_lock<std::mutex> lock(Base::result_mutex);
      Base::result = tmp;
    } catch (std::runtime_error &e) { NORM_ERR("%s", e.what()); }
  }

 public:
  rss_cb(uint32_t period, const std::string &uri)
      : Base(period, Base::Tuple(uri)) {}
};
}  // namespace

static void rss_process_info(char *p, int p_max_size, const std::string &uri,
                             char *action, int act_par, int interval,
                             unsigned int nrspaces) {
  char *str;

  uint32_t period = std::max(lround(interval / active_update_interval()), 1l);

  auto cb = conky::register_cb<rss_cb>(period, uri);

  assert(act_par >= 0 && action);

  std::shared_ptr<PRSS> data = cb->get_result_copy();

  if (!data || data->item_count < 1) {
    *p = 0;
  } else {
    /*
     * XXX: Refactor this so that we can retrieve any of the fields in the
     * PRSS struct (in prss.h).
     */
    if (strcmp(action, "feed_title") == EQUAL) {
      str = data->title;
      if (str && strlen(str) > 0) {
        // remove trailing new line if one exists
        if (str[strlen(str) - 1] == '\n') { str[strlen(str) - 1] = 0; }
        snprintf(p, p_max_size, "%s", str);
      }
    } else if (strcmp(action, "item_title") == EQUAL) {
      if (act_par < data->item_count) {
        str = data->items[act_par].title;
        // remove trailing new line if one exists
        if (str && strlen(str) > 0) {
          if (str[strlen(str) - 1] == '\n') { str[strlen(str) - 1] = 0; }
          snprintf(p, p_max_size, "%s", str);
        }
      }
    } else if (strcmp(action, "item_desc") == EQUAL) {
      if (act_par < data->item_count) {
        str = data->items[act_par].description;
        // remove trailing new line if one exists
        if (str && strlen(str) > 0) {
          if (str[strlen(str) - 1] == '\n') { str[strlen(str) - 1] = 0; }
          snprintf(p, p_max_size, "%s", str);
        }
      }
    } else if (strcmp(action, "item_titles") == EQUAL) {
      if (data->item_count > 0) {
        int itmp;
        int show;
        //'tmpspaces' is a string with spaces too be placed in front of each
        // title
        char *tmpspaces = (char *)malloc(nrspaces + 1);
        memset(tmpspaces, ' ', nrspaces);
        tmpspaces[nrspaces] = 0;

        if (act_par > data->item_count) {
          show = data->item_count;
        } else {
          show = act_par;
        }
        for (itmp = 0; itmp < show; itmp++) {
          PRSS_Item *item = &data->items[itmp];

          str = item->title;
          if (str) {
            // don't add new line before first item
            if (itmp > 0) { strncat(p, "\n", p_max_size); }
            /* remove trailing new line if one exists,
             * we have our own */
            if (strlen(str) > 0 && str[strlen(str) - 1] == '\n') {
              str[strlen(str) - 1] = 0;
            }
            strncat(p, tmpspaces, p_max_size);
            strncat(p, str, p_max_size);
          }
        }
        free(tmpspaces);
      }
    } else {
      NORM_ERR("rss: Invalid action '%s'", action);
    }
  }
}

void rss_scan_arg(struct text_object *obj, const char *arg) {
  int argc;
  struct rss_data *rd;

  rd = (struct rss_data *)malloc(sizeof(struct rss_data));
  memset(rd, 0, sizeof(struct rss_data));

  argc = sscanf(arg, "%127s %f %63s %d %u", rd->uri, &rd->interval, rd->action,
                &rd->act_par, &rd->nrspaces);
  if (argc < 3) {
    NORM_ERR("wrong number of arguments for $rss");
    free(rd);
    return;
  }
  obj->data.opaque = rd;
}

void rss_print_info(struct text_object *obj, char *p, unsigned int p_max_size) {
  struct rss_data *rd = (struct rss_data *)obj->data.opaque;

  if (!rd) {
    NORM_ERR("error processing RSS data");
    return;
  }
  rss_process_info(p, p_max_size, rd->uri, rd->action, rd->act_par,
                   rd->interval, rd->nrspaces);
}

void rss_free_obj_info(struct text_object *obj) {
  free_and_zero(obj->data.opaque);
}