<?php
/**
 * @brief Dotclear metadata class.
 *
 * Dotclear metadata class instance is provided by dcCore $meta property.
 *
 * @package Dotclear
 * @subpackage Core
 *
 * @copyright Olivier Meunier & Association Dotclear
 * @copyright GPL-2.0-only
 */

if (!defined('DC_RC_PATH')) {return;}

class dcMeta
{
    private $core;  ///< <b>dcCore</b> dcCore instance
    private $con;   ///< <b>connection</b>    Database connection object
    private $table; ///< <b>string</b> Media table name

    /**
    Object constructor.

    @param    core        <b>dcCore</b>        dcCore instance
     */
    public function __construct($core)
    {
        $this->core  = &$core;
        $this->con   = &$this->core->con;
        $this->table = $this->core->prefix . 'meta';
    }

    /**
    Splits up comma-separated values into an array of
    unique, URL-proof metadata values.

    @param    str        <b>string</b>        Comma-separated metadata.

    @return    <b>Array</b>    The array of sanitized metadata
     */
    public function splitMetaValues($str)
    {
        $res = array();
        foreach (explode(',', $str) as $i => $tag) {
            $tag = trim($tag);
            $tag = self::sanitizeMetaID($tag);

            if ($tag != false) {
                $res[$i] = $tag;
            }
        }

        return array_unique($res);
    }

    /**
    Make a metadata ID URL-proof.

    @param    str        <b>string</b>    the metadata ID.

    @return    <b>string</b>    The sanitized metadata
     */
    public static function sanitizeMetaID($str)
    {
        return text::tidyURL($str, false, true);
    }

    /**
    Converts serialized metadata (for instance in dc_post post_meta)
    into a meta array.

    @param    str        <b>string</b>    the serialized metadata.

    @return    <b>Array</b>    the resulting array of post meta
     */
    public function getMetaArray($str)
    {
        $meta = @unserialize($str);

        if (!is_array($meta)) {
            return array();
        }

        return $meta;
    }

    /**
    Converts serialized metadata (for instance in dc_post post_meta)
    into a comma-separated meta list for a given type.

    @param    str        <b>string</b>    the serialized metadata.
    @param    type    <b>string</b>    meta type to retrieve metaIDs from.

    @return    <b>string</b>    the comma-separated list of meta
     */
    public function getMetaStr($str, $type)
    {
        $meta = $this->getMetaArray($str);

        if (!isset($meta[$type])) {
            return '';
        }

        return implode(', ', $meta[$type]);
    }

    /**
    Converts serialized metadata (for instance in dc_post post_meta)
    into a "fetchable" metadata record.

    @param    str        <b>string</b>    the serialized metadata.
    @param    type    <b>string</b>    meta type to retrieve metaIDs from.

    @return    <b>record</b>    the meta recordset
     */
    public function getMetaRecordset($str, $type)
    {
        $meta = $this->getMetaArray($str);
        $data = array();

        if (isset($meta[$type])) {
            foreach ($meta[$type] as $v) {
                $data[] = array(
                    'meta_id'       => $v,
                    'meta_type'     => $type,
                    'meta_id_lower' => mb_strtolower($v),
                    'count'         => 0,
                    'percent'       => 0,
                    'roundpercent'  => 0
                );
            }
        }

        return staticRecord::newFromArray($data);
    }

    /**
    @deprecated since version 2.2 : $core->meta is always defined
    @see getMetaRecordset
    static version of getMetaRecordset
     */
    public static function getMetaRecord($core, $str, $type)
    {
        $meta = new self($core);
        return $meta->getMetaRecordset($str, $type);
    }

    /**
    Checks whether the current user is allowed to change post meta
    An exception is thrown if user is not allowed.

    @param    post_id    <b>string</b>    the post_id to check.
     */
    private function checkPermissionsOnPost($post_id)
    {
        $post_id = (integer) $post_id;

        if (!$this->core->auth->check('usage,contentadmin', $this->core->blog->id)) {
            throw new Exception(__('You are not allowed to change this entry status'));
        }

        #�If user can only publish, we need to check the post's owner
        if (!$this->core->auth->check('contentadmin', $this->core->blog->id)) {
            $strReq = 'SELECT post_id ' .
            'FROM ' . $this->core->prefix . 'post ' .
            'WHERE post_id = ' . $post_id . ' ' .
            "AND user_id = '" . $this->con->escape($this->core->auth->userID()) . "' ";

            $rs = $this->con->select($strReq);

            if ($rs->isEmpty()) {
                throw new Exception(__('You are not allowed to change this entry status'));
            }
        }
    }

    /**
    Updates serialized post_meta information with dc_meta table information.

    @param    post_id    <b>string</b>    the post_id to update.
     */
    private function updatePostMeta($post_id)
    {
        $post_id = (integer) $post_id;

        $strReq = 'SELECT meta_id, meta_type ' .
        'FROM ' . $this->table . ' ' .
            'WHERE post_id = ' . $post_id . ' ';

        $rs = $this->con->select($strReq);

        $meta = array();
        while ($rs->fetch()) {
            $meta[$rs->meta_type][] = $rs->meta_id;
        }

        $post_meta = serialize($meta);

        $cur            = $this->con->openCursor($this->core->prefix . 'post');
        $cur->post_meta = $post_meta;

        $cur->update('WHERE post_id = ' . $post_id);
        $this->core->blog->triggerBlog();
    }

    /**
    Retrieves posts corresponding to given meta criteria.
    <b>$params</b> is an array taking the following optional parameters:
    - meta_id : get posts having meta id
    - meta_type : get posts having meta type

    @param    params    <b>array</b>    Parameters
    @param    count_only    <b>boolean</b>        Only counts results

    @return    <b>record</b>    the resulting posts record
     */
    public function getPostsByMeta($params = array(), $count_only = false)
    {
        if (!isset($params['meta_id'])) {
            return;
        }

        $params['from'] = ', ' . $this->table . ' META ';
        $params['sql']  = 'AND META.post_id = P.post_id ';

        $params['sql'] .= "AND META.meta_id = '" . $this->con->escape($params['meta_id']) . "' ";

        if (!empty($params['meta_type'])) {
            $params['sql'] .= "AND META.meta_type = '" . $this->con->escape($params['meta_type']) . "' ";
            unset($params['meta_type']);
        }

        unset($params['meta_id']);

        return $this->core->blog->getPosts($params, $count_only);
    }

    /**
    Retrieves comments to posts corresponding to given meta criteria.
    <b>$params</b> is an array taking the following optional parameters:
    - meta_id : get comments to posts having meta id
    - meta_type : get comments to posts having meta type

    @param    params    <b>array</b>    Parameters
    @param    count_only    <b>boolean</b>        Only counts results

    @return    <b>record</b>    the resulting comments record
     */
    public function getCommentsByMeta($params = array(), $count_only = false)
    {
        if (!isset($params['meta_id'])) {
            return;
        }

        $params['from'] = ', ' . $this->table . ' META ';
        $params['sql']  = 'AND META.post_id = P.post_id ';
        $params['sql'] .= "AND META.meta_id = '" . $this->con->escape($params['meta_id']) . "' ";

        if (!empty($params['meta_type'])) {
            $params['sql'] .= "AND META.meta_type = '" . $this->con->escape($params['meta_type']) . "' ";
            unset($params['meta_type']);
        }

        return $this->core->blog->getComments($params, $count_only);
    }

    /**
    @deprecated since 2.2. Use getMetadata and computeMetaStats instead.
    Generic-purpose metadata retrieval : gets metadatas according to given
    criteria. Metadata get enriched with stastistics columns (only relevant
    if limit parameter is not set). Metadata are sorted by post count
    descending

    @param    type    <b>string</b>    if not null, get metas having the given type
    @param    limit    <b>string</b>    if not null, number of max fetched metas
    @param    meta_id    <b>string</b>    if not null, get metas having the given id
    @param    post_id    <b>string</b>    if not null, get metas for the given post id

    @return    <b>record</b>    the meta recordset
     */
    public function getMeta($type = null, $limit = null, $meta_id = null, $post_id = null)
    {
        $params = array();

        if ($type != null) {
            $params['meta_type'] = $type;
        }

        if ($limit != null) {
            $params['limit'] = $limit;
        }

        if ($meta_id != null) {
            $params['meta_id'] = $meta_id;
        }

        if ($meta_id != null) {
            $params['post_id'] = $post_id;
        }

        $rs = $this->getMetadata($params, false);
        return $this->computeMetaStats($rs);
    }

    /**
    Generic-purpose metadata retrieval : gets metadatas according to given
    criteria. <b>$params</b> is an array taking the following
    optionnal parameters:

    - type: get metas having the given type
    - meta_id: if not null, get metas having the given id
    - post_id: get metas for the given post id
    - limit: number of max fetched metas
    - order: results order (default : posts count DESC)

    @param    params        <b>array</b>        Parameters
    @param    count_only    <b>boolean</b>        Only counts results

    @return    <b>record</b>    the resulting comments record
     */
    public function getMetadata($params = array(), $count_only = false)
    {
        if ($count_only) {
            $strReq = 'SELECT count(distinct M.meta_id) ';
        } else {
            $strReq = 'SELECT M.meta_id, M.meta_type, COUNT(M.post_id) as count, MAX(P.post_dt) as latest, MIN(P.post_dt) as oldest ';
        }

        $strReq .=
        'FROM ' . $this->table . ' M LEFT JOIN ' . $this->core->prefix . 'post P ' .
        'ON M.post_id = P.post_id ' .
        "WHERE P.blog_id = '" . $this->con->escape($this->core->blog->id) . "' ";

        if (isset($params['meta_type'])) {
            $strReq .= " AND meta_type = '" . $this->con->escape($params['meta_type']) . "' ";
        }

        if (isset($params['meta_id'])) {
            $strReq .= " AND meta_id = '" . $this->con->escape($params['meta_id']) . "' ";
        }

        if (isset($params['post_id'])) {
            $strReq .= ' AND P.post_id ' . $this->con->in($params['post_id']) . ' ';
        }

        if (!$this->core->auth->check('contentadmin', $this->core->blog->id)) {
            $strReq .= 'AND ((post_status = 1 ';

            if ($this->core->blog->without_password) {
                $strReq .= 'AND post_password IS NULL ';
            }
            $strReq .= ') ';

            if ($this->core->auth->userID()) {
                $strReq .= "OR P.user_id = '" . $this->con->escape($this->core->auth->userID()) . "')";
            } else {
                $strReq .= ') ';
            }
        }

        if (!$count_only) {
            if (!isset($params['order'])) {
                $params['order'] = 'count DESC';
            }

            $strReq .=
                'GROUP BY meta_id,meta_type,P.blog_id ' .
                'ORDER BY ' . $params['order'];

            if (isset($params['limit'])) {
                $strReq .= $this->con->limit($params['limit']);
            }
        }

        $rs = $this->con->select($strReq);
        return $rs;
    }

    /**
    Computes statistics from a metadata recordset.
    Each record gets enriched with lowercase name, percent and roundpercent columns

    @param    rs    <b>record</b>    recordset to enrich

    @return    <b>record</b>    the enriched recordset
     */
    public function computeMetaStats($rs)
    {
        $rs_static = $rs->toStatic();

        $max = array();
        while ($rs_static->fetch()) {
            $type = $rs_static->meta_type;
            if (!isset($max[$type])) {
                $max[$type] = $rs_static->count;
            } else {
                if ($rs_static->count > $max[$type]) {
                    $max[$type] = $rs_static->count;
                }
            }
        }

        while ($rs_static->fetch()) {
            $rs_static->set('meta_id_lower', dcUtils::removeDiacritics(mb_strtolower($rs_static->meta_id)));

            $count   = $rs_static->count;
            $percent = ((integer) $rs_static->count) * 100 / $max[$rs_static->meta_type];

            $rs_static->set('percent', (integer) round($percent));
            $rs_static->set('roundpercent', round($percent / 10) * 10);
        }

        return $rs_static;
    }

    /**
    Adds a metadata to a post.

    @param    post_id    <b>integer</b>    the post id
    @param    type    <b>string</b>    meta type
    @param    value    <b>integer</b>    meta value
     */
    public function setPostMeta($post_id, $type, $value)
    {
        $this->checkPermissionsOnPost($post_id);

        $value = trim($value);
        if ($value === false) {return;}

        $cur = $this->con->openCursor($this->table);

        $cur->post_id   = (integer) $post_id;
        $cur->meta_id   = (string) $value;
        $cur->meta_type = (string) $type;

        $cur->insert();
        $this->updatePostMeta((integer) $post_id);
    }

    /**
    Removes metadata from a post.

    @param    post_id    <b>integer</b>    the post id
    @param    type    <b>string</b>    meta type (if null, delete all types)
    @param    value    <b>integer</b>    meta value (if null, delete all values)
     */
    public function delPostMeta($post_id, $type = null, $meta_id = null)
    {
        $post_id = (integer) $post_id;

        $this->checkPermissionsOnPost($post_id);

        $strReq = 'DELETE FROM ' . $this->table . ' ' .
            'WHERE post_id = ' . $post_id;

        if ($type !== null) {
            $strReq .= " AND meta_type = '" . $this->con->escape($type) . "' ";
        }

        if ($meta_id !== null) {
            $strReq .= " AND meta_id = '" . $this->con->escape($meta_id) . "' ";
        }

        $this->con->execute($strReq);
        $this->updatePostMeta((integer) $post_id);
    }

    /**
    Mass updates metadata for a given post_type.

    @param    meta_id        <b>integer</b>    old value
    @param    new_meta    <b>integer</b>    new value
    @param    type    <b>string</b>    meta type (if null, select all types)
    @param    post_type    <b>integer</b>    impacted post_type (if null, select all types)
    @return    <b>boolean</b>    true if at least 1 post has been impacted
     */
    public function updateMeta($meta_id, $new_meta_id, $type = null, $post_type = null)
    {
        $new_meta_id = self::sanitizeMetaID($new_meta_id);

        if ($new_meta_id == $meta_id) {
            return true;
        }

        $getReq = 'SELECT M.post_id ' .
        'FROM ' . $this->table . ' M, ' . $this->core->prefix . 'post P ' .
        'WHERE P.post_id = M.post_id ' .
        "AND P.blog_id = '" . $this->con->escape($this->core->blog->id) . "' " .
            "AND meta_id = '%s' ";

        if (!$this->core->auth->check('contentadmin', $this->core->blog->id)) {
            $getReq .= "AND P.user_id = '" . $this->con->escape($this->core->auth->userID()) . "' ";
        }
        if ($post_type !== null) {
            $getReq .= "AND P.post_type = '" . $this->con->escape($post_type) . "' ";
        }

        $delReq = 'DELETE FROM ' . $this->table . ' ' .
            'WHERE post_id IN (%s) ' .
            "AND meta_id = '%s' ";

        $updReq = 'UPDATE ' . $this->table . ' ' .
            "SET meta_id = '%s' " .
            'WHERE post_id IN (%s) ' .
            "AND meta_id = '%s' ";

        if ($type !== null) {
            $plus = " AND meta_type = '%s' ";
            $getReq .= $plus;
            $delReq .= $plus;
            $updReq .= $plus;
        }

        $to_update = $to_remove = array();

        $rs = $this->con->select(sprintf($getReq, $this->con->escape($meta_id),
            $this->con->escape($type)));

        while ($rs->fetch()) {
            $to_update[] = $rs->post_id;
        }

        if (empty($to_update)) {
            return false;
        }

        $rs = $this->con->select(sprintf($getReq, $new_meta_id, $type));
        while ($rs->fetch()) {
            if (in_array($rs->post_id, $to_update)) {
                $to_remove[] = $rs->post_id;
                unset($to_update[array_search($rs->post_id, $to_update)]);
            }
        }

        # Delete duplicate meta
        if (!empty($to_remove)) {
            $this->con->execute(sprintf($delReq, implode(',', $to_remove),
                $this->con->escape($meta_id),
                $this->con->escape($type)));

            foreach ($to_remove as $post_id) {
                $this->updatePostMeta($post_id);
            }
        }

        # Update meta
        if (!empty($to_update)) {
            $this->con->execute(sprintf($updReq, $this->con->escape($new_meta_id),
                implode(',', $to_update),
                $this->con->escape($meta_id),
                $this->con->escape($type)));

            foreach ($to_update as $post_id) {
                $this->updatePostMeta($post_id);
            }
        }

        return true;
    }

    /**
    Mass delete metadata for a given post_type.

    @param    meta_id        <b>integer</b>    meta value
    @param    type    <b>string</b>    meta type (if null, select all types)
    @param    post_type    <b>integer</b>    impacted post_type (if null, select all types)
    @return    <b>Array</b>    the list of impacted post_ids
     */
    public function delMeta($meta_id, $type = null, $post_type = null)
    {
        $strReq = 'SELECT M.post_id ' .
        'FROM ' . $this->table . ' M, ' . $this->core->prefix . 'post P ' .
        'WHERE P.post_id = M.post_id ' .
        "AND P.blog_id = '" . $this->con->escape($this->core->blog->id) . "' " .
        "AND meta_id = '" . $this->con->escape($meta_id) . "' ";

        if ($type !== null) {
            $strReq .= " AND meta_type = '" . $this->con->escape($type) . "' ";
        }

        if ($post_type !== null) {
            $strReq .= " AND P.post_type = '" . $this->con->escape($post_type) . "' ";
        }

        $rs = $this->con->select($strReq);

        if ($rs->isEmpty()) {
            return array();
        }

        $ids = array();
        while ($rs->fetch()) {
            $ids[] = $rs->post_id;
        }

        $strReq = 'DELETE FROM ' . $this->table . ' ' .
        'WHERE post_id IN (' . implode(',', $ids) . ') ' .
        "AND meta_id = '" . $this->con->escape($meta_id) . "' ";

        if ($type !== null) {
            $strReq .= " AND meta_type = '" . $this->con->escape($type) . "' ";
        }

        $rs = $this->con->execute($strReq);

        foreach ($ids as $post_id) {
            $this->updatePostMeta($post_id);
        }

        return $ids;
    }
}