<?php
/**
 * smiley.php - model class for a smiley
 *
 * 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 2 of
 * the License, or (at your option) any later version.
 *
 * @author      Jan-Hendrik Willms <tleilax+studip@gmail.com>
 * @category    Stud.IP
 * @package     admin
 * @since       2.3
 *
 * @uses        DBManager
 * @uses        SmileyFavorites
 * @uses        SmileyFormat
 */
class Smiley
{
    const FETCH_ALL = 0;
    const FETCH_ID  = 1;

    private static $shortnames = null;

    public $id          = null;
    public $name        = '';
    public $width       = 0;
    public $height      = 0;
    public $short       = '';
    public $count       = 0;
    public $short_count = 0;
    public $fav_count   = 0;
    public $mkdate      = null;
    public $chdate      = null;

    /**
     * Returns the absolute filename of a smiley.
     *
     * @param  mixed  $name Smiley name, defaults to current smiley's name
     * @return String Absolute filename
     */
    public static function getFilename($name)
    {
        return sprintf('%s/smile/%s', realpath($GLOBALS['DYNAMIC_CONTENT_PATH']), $name);
    }

    /**
     * Returns the smiley object with the given id. If no such object is
     * available, an empty object is returned.
     *
     * @param  int    $id Id of the smiley to load
     * @return Smiley Smiley object
     */
    public static function getById($id)
    {
        $result = self::getByIds($id);
        return reset($result) ?: new self;
    }

    /**
     * Returns a collection smiley objects with the given ids.
     *
     * @param  mixed $ids Ids of the smileys to load, also accepts an atomic id
     * @return Array Array of Smiley objects
     */
    public static function getByIds($ids)
    {
        if (empty($ids)) {
            return [];
        }
        $query = "SELECT smiley_id AS id, smiley_name AS name, smiley_width AS width, smiley_height AS height, "
               . " short_name AS short, smiley_counter AS `count`, short_counter AS short_count, "
               . " fav_counter AS fav_count, mkdate, chdate "
               . " FROM smiley WHERE smiley_id IN (?)";
        $statement = DBManager::get()->prepare($query);
        $statement->execute([$ids]);
        return $statement->fetchAll(PDO::FETCH_CLASS, 'Smiley');
    }

    /**
     * Returns the smiley object with the given name. If no such object is
     * available, an empty object is returned
     *
     * @param  String $name Name of the smiley to load
     * @return Smiley Smiley object
     */
    public static function getByName($name)
    {
        $query = "SELECT smiley_id AS id, smiley_name AS name, smiley_width AS width, smiley_height AS height, "
               . " short_name AS short, smiley_counter AS `count`, short_counter AS short_count, "
               . " fav_counter AS fav_count, mkdate, chdate "
               . " FROM smiley WHERE smiley_name = ?";
        $statement = DBManager::get()->prepare($query);
        $statement->execute([$name]);
        return $statement->fetchObject('Smiley') ?: new self();
    }

    /**
     * Returns the smiley object with the given short notation. If no such
     * object is available, an empty object is returned
     *
     * @param  String $short Short notation of the smiley to load
     * @return Smiley Smiley object
     */
    public static function getByShort($short)
    {
        $smileys = self::getShort();
        $name   = $smileys[$short];

        return isset($name) ? self::getByName($name) : new self();
    }

    /**
     * Removes a smiley or a collection of smileys from the database.
     *
     * @param  mixed  $id Id(s) to delete, accepts either an atomic id or an
     *                    array of ids
     */
    public static function Remove($id)
    {
        if ($id) {
            foreach (self::getByIds($id) as $smiley) {
                unlink(self::getFilename($smiley->name));
            }
            DBManager::get()
                ->prepare("DELETE FROM smiley WHERE smiley_id IN (?)")
                ->execute([$id]);
        }
    }

    /**
     * Generates the neccessary sql query to load the given group's items.
     *
     * @param  String $group Group to load
     * @return String SQL query to load the given group's items
     */
    private static function groupQuery($group)
    {
        $query = "SELECT smiley_id AS id, smiley_name AS name, smiley_width AS width, smiley_height AS height, "
               . " short_name AS short, smiley_counter AS `count`, short_counter AS short_count, "
               . " fav_counter AS fav_count, mkdate, chdate FROM smiley ";
        switch ($group) {
            case 'all':
                $query .= "ORDER BY smiley_name";
                break;
            case 'top20':
                $query .= "WHERE smiley_counter > 0 OR short_counter > 0 "
                       .  "ORDER BY smiley_counter + short_counter DESC, smiley_name ASC "
                       .  "LIMIT 20";
                break;
            case 'used':
                $query .= "WHERE smiley_counter > 0 OR short_counter > 0 "
                       .  "ORDER BY smiley_counter + short_counter DESC, smiley_name ASC";
                break;
            case 'none':
                $query .= "WHERE smiley_counter=0 AND short_counter=0 ORDER BY smiley_name";
                break;
            case 'short':
                $query .= "WHERE short_name != '' ORDER BY smiley_name";
                break;
            default:
                $query .= sprintf("WHERE smiley_name LIKE CONCAT(%s, '%%') ORDER BY smiley_name",
                                  DBManager::get()->quote($group));
                break;
        }
        return $query;
    }

    /**
     * Loads a given group from the database.
     *
     * @param  String $group Group to load, defaults to 'all'
     * @param  int    $mode  Fetch mode
     *                      - FETCH_ALL to return actual Smiley objects
     *                      - FETCH_ID  to return the group's items' ids
     * @return Array Either the objects or the ids of the group's items
     */
    static function getGrouped($group = 'all', $mode = self::FETCH_ALL)
    {
        $result = DBManager::get()
            ->query(self::groupQuery($group))
            ->fetchAll(PDO::FETCH_CLASS, 'Smiley');

        if ($mode & self::FETCH_ID) {
            $result = array_map(function ($item) { return $item->id; }, $result);
        }
        return $result;
    }

    /**
     * Returns an ordered unique list of the first characters of all smileys.
     *
     * @return Array Ordered list of all first characters
     */
    static function getFirstUsedCharacter()
    {
        return DBManager::get()
            ->query("SELECT LEFT(smiley_name, 1) FROM smiley ORDER BY smiley_name")
            ->fetchColumn();
    }

    /**
     * Returns an associative list of the first characters of all smileys
     * and their according quantity.
     *
     * @return Array Associative list with character as key and quantity as
     *               value
     */
    static function getUsedCharacters()
    {
        $query = "SELECT LEFT(smiley_name, 1), COUNT(smiley_name) "
               . "FROM smiley GROUP BY LEFT(smiley_name, 1)";
        return DBManager::get()
            ->query($query)
            ->fetchGrouped(PDO::FETCH_COLUMN);
    }

    /**
     * Returns a list of all available short notations.
     *
     * @return Array Associative list with short notation as key and smiley
     *               name as value
     */
    public static function getShort()
    {
        if (class_exists('DBManager') && !$GLOBALS['SMILEY_NO_DB']) {
            if (self::$shortnames === null) {
                $query = "SELECT short_name, smiley_name FROM smiley WHERE short_name != ''";
                self::$shortnames = DBManager::get()->query($query)->fetchGrouped(PDO::FETCH_COLUMN);
            }
            return self::$shortnames;
        } else { // Unit test
            $short = (array) $GLOBALS['SMILE_SHORT'];
        }

        return $short;
    }

    /**
     * Returns some statistics about the smiley database.
     *
     * @return Array 4 numbers: available, used, occurences and last change
     */
    public static function getStatistics()
    {
        $query = "SELECT COUNT(*) AS count_all, "
               . " SUM(smiley_counter + short_counter > 0) AS count_used, "
               . " SUM(smiley_counter + short_counter) AS `sum`, "
               . " MAX(chdate) AS last_change "
               . "FROM smiley";
        return DBManager::get()
            ->query($query)
            ->fetch(PDO::FETCH_ASSOC);
    }

    /**
     * Searches the database for occurences of smileys and returns a list
     * of how often each smiley was used.
     * If smiley favorites are activated, the list will include the number
     * how often a smiley was favored.
     *
     * @return Array Associative array with smiley name as key and according
     *               usage numbers as value
     */
    public static function getUsage()
    {
        // Tabellen, die nach Smileys durchsucht werden sollen
        // Format: array( array (Tabelle, Feld), array (Tabelle, Feld), ... )
        $table_data = [
            ['datafields_entries', 'content'],
            ['kategorien', 'content'],
            ['message', 'message'],
            ['news', 'body'],
            ['scm', 'content'],
            ['user_info', 'hobby'],
            ['user_info', 'lebenslauf'],
            ['user_info', 'publi'],
            ['user_info', 'schwerp'],
            ['wiki', 'body'],
            ['forum_entries', 'content']
        ];

        // add tables from ForumModules to count for
        foreach (PluginEngine::getPlugins('ForumModule') as $plugin) {
            $table = $plugin->getEntryTableInfo();
            $table_data[] = [$table['table'], $table['content']];
        }

        // search in all tables
        $usage = [];
        foreach ($table_data as $table) {
            // only fetch entries which have some content, otherwise the while-loop will fail
            $query = "SELECT ? AS txt FROM ? WHERE LENGTH(?) > 0"; // $table1, $table0
            if ($table[0] == 'wiki') {  // only the actual wiki page ...
                $sqltxt = "SELECT MAX(CONCAT(LPAD(version, 5, '0'),' ', ?)) AS txt FROM ? GROUP BY range_id, keyword";
            }

            $statement = DBManager::get()->prepare($query);
            $statement->bindParam(1, $table[1], StudipPDO::PARAM_COLUMN);
            $statement->bindParam(2, $table[0], StudipPDO::PARAM_COLUMN);
            $statement->bindParam(3, $table[1], StudipPDO::PARAM_COLUMN);
            $statement->execute([]);

            // and all entrys
            while ($txt = $statement->fetchColumn()) {
                // extract all smileys
                if (preg_match_all('/' . SmileyFormat::REGEXP . '/u', $txt, $matches)) {
                    for ($k = 0; $k < count($matches[2]); $k++) {
                        $name = $matches[2][$k];
                        if (!isset($usage[$name])) {
                            $usage[$name] = ['count' => 0, 'short_count' => 0, 'favorites' => 0];
                        }
                        $usage[$name]['count'] += 1;
                    }
                }
                // and now the short-notation
                foreach (self::getShort() as $code => $name) {
                    $regexp = '/(\>|^|\s)' . preg_quote($code) . '(?=$|\<|\s)/u';
                    if ($count = preg_match_all($regexp, $txt, $matches)) {
                        if (!isset($usage[$name])) {
                            $usage[$name] = ['count' => 0, 'short_count' => 0, 'favorites' => 0];
                        }
                        $usage[$name]['short_count'] += $count;
                    }
                }
            }
        }

        // favorites
        if (SmileyFavorites::isEnabled()) {
            $favorite_usage = SmileyFavorites::getUsage();
            foreach ($favorite_usage as $name => $count) {
                if (!isset($usage[$name])) {
                    $usage[$name] = ['count' => 0, 'short_count' => 0, 'favorites' => 0];
                }
                $usage[$name]['favorites'] = $count;
            }
        }

        return $usage;
    }

    /**
     * Refreshes the database with current usage numbers.
     *
     * @return int Number of changed objects
     */
    public static function updateUsage()
    {
        $usage = self::getUsage();
        $smileys = self::getGrouped('all');
        $changed = 0;

        foreach ($smileys as $smiley) {
            $updated = $usage[$smiley->name];
            if (!isset($updated)
                && $smiley->count + $smiley->short_count + $smiley->fav_count > 0)
            {
                $smiley->count       = 0;
                $smiley->short_count = 0;
                $smiley->fav_count   = 0;
            } else if ($smiley->count + $smiley->short_count + $smiley->fav_count
                       != $updated['count'] + $updated['short_count'] + $updated['favorites']) {
                $smiley->count       = $updated['count'];
                $smiley->short_count = $updated['short_count'];
                $smiley->fav_count   = $updated['favorites'];
            } else {
                continue;
            }
            $smiley->store();
            $changed++;
        }

        return $changed;
    }

    /**
     * Synchronizes the smileys' file system or an atomic file with the
     * database.
     * The smiley directory is scanned for new, changed or missing files.
     * Any difference will change the database's record.
     *
     * This method is also used for uploading new smileys. Provide an
     * absolute filename of a smiley and it will either be imported into
     * the database or the database will be adjusted to the current file's
     * dimensions.
     *
     * @param mixed $smiley_file If no filename is provided, the whole file
     *                           system is refreshed
     * @return Array Numbers: inserted, updated, removed (, favorites adjusted)
     */
    public static function refresh($smiley_file = null)
    {
        $counts = [
            'insert'    => 0,
            'update'    => 0
        ];

        if ($filename === null) {
            $files = glob(self::getFilename('*'));
        } else {
            $files = [$smiley_file];
        }

        foreach ($files as $file) {
            $image_info = getimagesize($file);
            if ($image_info[2] !== IMAGETYPE_GIF) {
                continue;
            }

            $name = mb_substr(basename($file), 0, mb_strrpos(basename($file), "."));
            //$name = basename($file, '.gif');
            $smiley = Smiley::getByName($name);

            $update = false;
            if (!$smiley->id) {
                $smiley->name  = $name;
                $smiley->short = array_search($name, $GLOBALS['SMILE_SHORT']) ?: '';
                $smiley->width  = $image_info[0];
                $smiley->height = $image_info[1];

                $update = true;
                $counts['insert'] += 1;
            } else if ($smiley->width + $smiley->height != $image_info[0] + $image_info[1]) {
                $smiley->width  = $image_info[0];
                $smiley->height = $image_info[1];

                $update = true;
                $counts['update'] += 1;
            }

            //$smiley->width || $smiley->width = 20;
            //$smiley->height || $smiley->height = 20;

            if ($update) {
                $smiley->store();
            }

            $ids[] = $smiley->id;
        }

        $db_ids = self::getGrouped('all', self::FETCH_ID);
        $missing = array_diff($db_ids, $ids);
        self::Remove($missing);
        $counts['delete'] = count($missing);

        if (SmileyFavorites::isEnabled()) {
            $counts['favorites'] = SmileyFavorites::gc();
        }

        return $counts;
    }

    /**
     * Returns the url of a smiley.
     *
     * @param  mixed  $name Smiley name, defaults to current smiley's name
     * @return String URL
     */
    public function getURL($name = null)
    {
        return sprintf('%s/smile/%s.gif', $GLOBALS['DYNAMIC_CONTENT_URL'], urlencode($name ?: $this->name));
    }

    /**
     * Returns the HTML image tag of the smiley
     *
     * @param  mixed  $tooltip Tooltip to display for this smiley, defaults to
     *                         smiley's name
     * @return String HTML image tag
     * @see    Smiley::img
     */
    public function getImageTag($tooltip = null)
    {
        return $this->img($this->name, $tooltip, $this->width, $this->height);
    }

    /**
     * Returns the HTML image tag of any smiley.
     *
     * @param  String $name    Name of the smiley
     * @param  mixed  $tooltip Tooltip to display for this smiley, defaults to
     *                         smiley's name
     * @param  mixed  $width   Width of the smiley
     * @param  mixed  $height  Height of the smiley
     * @return String HTML image tag
     */
    public function img($name, $tooltip = null, $width = null, $height = null)
    {
        return sprintf(
            '<img src="%s" alt="%s" title="%s" width="%s" height="%s">',
            $this->getURL(),
            htmlReady($name),
            htmlReady($tooltip ?: $name),
            $width,
            $height
        );
    }

    /**
     * Stores the current smiley to database.
     */
    public function store()
    {
        $query = "INSERT INTO smiley (
                    smiley_id, smiley_name, smiley_width, smiley_height, short_name,
                    smiley_counter, short_counter, fav_counter, mkdate, chdate
                  ) VALUES (
                    ?, ?, ?, ?, ?, ?, ?, ?, UNIX_TIMESTAMP(), UNIX_TIMESTAMP()
                  )
                  ON DUPLICATE KEY
                    UPDATE smiley_name = VALUES(smiley_name),
                           smiley_width = VALUES(smiley_width),
                           smiley_height = VALUES(smiley_height),
                           short_name = VALUES(short_name),
                           smiley_counter = VALUES(smiley_counter),
                           short_counter = VALUES(short_counter),
                           fav_counter = VALUES(fav_counter),
                           chdate = VALUES(chdate)";
        DBManager::get()
            ->prepare($query)
            ->execute([
               $this->id, $this->name, $this->width, $this->height, $this->short,
               $this->count, $this->short_count, $this->fav_count
            ]);
        if (!$this->id) {
            $this->id = DBManager::get()->lastInsertId();
        }
    }

    /**
     * Renames the smiley to the given new name.
     *
     * @param String $new_name New name of the smiley
     * @return bool  true if smiley was renamed successfully, false otherwise
     */
    public function rename($new_name)
    {
        $old_file = self::getFilename($this->name);
        $new_file = self::getFilename($new_name);

        if (!rename($old_file, $new_file)) {
            return false;
        }

        $this->name = $new_name;
        $this->store();

        return true;
    }

    /**
     * Deletes the smiley.
     */
    public function delete()
    {
        if ($this->id) {
            self::Remove($this->id);

            $this->id          = null;
            $this->name        = '';
            $this->width       = 0;
            $this->height      = 0;
            $this->short       = '';
            $this->count       = 0;
            $this->short_count = 0;
            $this->fav_count   = 0;
            $this->mkdate      = null;
            $this->chdate      = null;
        }
    }
}