<?php
/**
* SeekQuarry/Yioop --
* Open Source Pure PHP Search Engine, Crawler, and Indexer
*
* Copyright (C) 2009 - 2020 Chris Pollett chris@pollett.org
*
* LICENSE:
*
* 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 <https://www.gnu.org/licenses/>.
*
* END LICENSE
*
* @author Timothy Chow
* @license https://www.gnu.org/licenses/ GPL3
* @link https://www.seekquarry.com/
* @copyright 2009 - 2020
* @filesource
*/
namespace seekquarry\yioop\models;
use seekquarry\yioop as B;
use seekquarry\yioop\configs as C;
use seekquarry\yioop\library as L;
use seekquarry\yioop\library\MediaConstants;
use seekquarry\yioop\library\VersionManager;
use seekquarry\yioop\library\WikiParser;
use seekquarry\yioop\library\processors\ImageProcessor;
use seekquarry\yioop\models\ImpressionModel;
/**
* This is class is used to handle
* db results related to Group Administration. Groups are collections of
* users who might access a common blog/news feed and set of pages. This
* method also controls adding and deleting entries to a group feed and
* does limited access control checks of these operations.
*
* @author Timothy Chow
*/
class TrendingModel extends Model implements MediaConstants
{
/**
* Computes an array of the top $limit to $limit+$num terms from feed items
* for the update periods listed as an array. If no periods are
* provided, then the period hour, day, week are used.
*
* @param string $locale_tag language to get top terms for
* @param array $update_periods as array of update periods.
* Items in this array should be from intervals pre-defined in
* Config.php such as ONE_HOUR, ONE_DAY, or ONE_WEEK.
* @param string $category used to compute the trending terms with
* respect to
* @param array $order_by for either of the two fields TERM,
* SCORE (or OCCURRENCES) lets you specify a sort direction on the
* tending values. For example, ["TERM" => "ASC"] or ["SCORE" => "DESC"]
* @param int $limit the rank of the first trending term tooutput
* @param int $num number of trending terms desired
* @return array consists of one array/update period, each of these
* arrays consist of a rank => [term, occurrences] for the
* top NUM_TRENDING results for that period.
*/
public function topTermsForUpdatePeriods($locale_tag, $update_periods,
$category, $order_by = [], $limit = 0, $num = C\NUM_TRENDING)
{
$db = $this->db;
if (empty($update_periods)) {
$update_periods = [C\ONE_HOUR, C\ONE_DAY, C\ONE_WEEK,
C\ONE_MONTH, C\ONE_YEAR];
}
$default_order_string = "ORDER BY OCCURRENCES DESC";
$order_string = "ORDER BY ";
$comma = "";
foreach ($order_by as $field => $values) {
$field = (mb_strtoupper($field) == "SCORE") ? "OCCURRENCES" :
$field;
$values = mb_strtoupper($values);
if (in_array($values, ['ASC', 'DESC'])) {
$order_string .= $comma . $field . " " . $values;
$comma = ", ";
}
}
if ($order_string == "ORDER BY ") {
$order_string = $default_order_string;
}
$sql = "SELECT TERM, OCCURRENCES FROM TRENDING_TERM ".
"WHERE LANGUAGE= ? AND UPDATE_PERIOD = ? AND CATEGORY =? AND ".
"TIMESTAMP = (SELECT MAX(TIMESTAMP) " .
"FROM TRENDING_TERM WHERE LANGUAGE= ? AND UPDATE_PERIOD = ?) " .
"$order_string ".
$db->limitOffset($limit, $num);
$top_results = [];
foreach($update_periods as $period) {
$result = $db->execute($sql, [$locale_tag, $period, $category,
$locale_tag, $period]);
$term_occurrences = [];
if($result) {
while($term_occurrence = $db->fetchArray($result)) {
$term_occurrences[] = $term_occurrence;
}
}
$top_results[$period] = $term_occurrences;
}
return $top_results;
}
/**
* Returns a list of $num_term many random tending terms from the
* sets of trending terms across all tracked time periods with respect
* to category supplied.
*
* @param string $locale_tag language to get random trending terms for
* @return array terms which are trending
*/
public function randomTrends($locale_tag, $category = 'news', $num_terms =
C\NUM_RESULTS_PER_PAGE)
{
$trend_dir = C\WORK_DIRECTORY . "/cache/trends";
$random_trends_file = "$trend_dir/random_"
. "{$category}_{$locale_tag}.txt";
if (file_exists($random_trends_file) &&
filemtime($random_trends_file) + (5 * C\ONE_MINUTE) > time()) {
return unserialize(file_get_contents($random_trends_file));
}
$trend_data = $this->topTermsForUpdatePeriods($locale_tag, [],
$category);
$trending = [];
foreach ($trend_data as $period => $trend_data) {
$trending = array_merge($trending, $trend_data);
}
usort($trending, function($a, $b) {
if ($a['OCCURRENCES'] == $b['OCCURRENCES']) {
return 0;
}
return ($a['OCCURRENCES'] > $b['OCCURRENCES']) ? -1 : 1;
});
$total = array_sum(array_column($trending, "OCCURRENCES"));
if (count($trending) > $num_terms && $total >= 1) {
$trending_terms = [];
while (count($trending_terms) < $num_terms) {
$random_pick = mt_rand(0, intval($total) * 1000)/1000;
$prob = 0;
foreach ($trending as $trend) {
$next_prob = $prob + $trend['OCCURRENCES'];
if ($next_prob >= $random_pick &&
empty($trending_terms[$trend['TERM']])) {
$trending_terms[$trend['TERM']] = $trend['TERM'];
break;
}
$prob = $next_prob;
}
}
$trending_terms = array_values($trending_terms);
} else {
$trending_terms = array_column($trending, "TERM");
}
if (!file_exists($trend_dir)) {
mkdir($trend_dir);
chmod($trend_dir, 0777);
}
file_put_contents($random_trends_file, serialize($trending_terms));
set_error_handler(null);
@chmod($random_trends_file, 0777);
set_error_handler(C\NS_CONFIGS . "yioop_error_handler");
return $trending_terms;
}
/**
* Return trending scores for a term with respect to a locale
* over the appropriate sub-period for the last period. For example,
* Donald Trump in en-US locale, for the last day. Here the subinterval
* would be hourly.
*
* @param string $term to find time => score data for
* @param int $period time period to get subinterval data for
* @param string $locale_tag which locale to get trending data for
* @param bool $raw whether to keep as linux timestamps or to format into
* appropriate date units for subinterval
* @return array associative array of time => scores
*/
public function termScoresForPeriod($term, $period, $locale_tag,
$raw = false)
{
$db = $this->db;
$subintervals = [ C\ONE_HOUR => C\ONE_MINUTE,
C\ONE_DAY => C\ONE_HOUR, C\ONE_WEEK => C\ONE_DAY,
C\ONE_MONTH => C\ONE_WEEK, C\ONE_YEAR => C\ONE_MONTH
];
$dates = [ C\ONE_HOUR => 'i', C\ONE_DAY => 'H', C\ONE_WEEK => 'D',
C\ONE_MONTH => 'W', C\ONE_YEAR => 'm'
];
$sub_period = (empty($subintervals[$period])) ? C\ONE_HOUR :
$subintervals[$period];
$num_results = (empty($subintervals[$period])) ?
C\ONE_HOUR/C\ONE_MINUTE : ceil($period / $sub_period);
$date_format = (empty($dates[$period])) ? 'r' : $dates[$period];
$sql = "SELECT OCCURRENCES, TIMESTAMP FROM TRENDING_TERM ".
"WHERE TERM = ? AND UPDATE_PERIOD = ? AND LANGUAGE= ? " .
"ORDER BY TIMESTAMP DESC ".
$db->limitOffset($num_results);
$result = $db->execute($sql, [$term, $sub_period, $locale_tag]);
$pre_occurrences = [];
if($result) {
$i = 0;
while($row = $db->fetchArray($result)) {
$pre_occurrences[$row['TIMESTAMP']] = $row['OCCURRENCES'];
}
}
ksort($pre_occurrences);
if ($raw) {
return $pre_occurrences;
}
$timestamp_occurrences = [];
foreach ($pre_occurrences as $timestamp => $occurrences) {
$date = date($date_format, $timestamp);
$timestamp_occurrences[$date] = $occurrences;
}
return $timestamp_occurrences;
}
}