<?php

/* For licensing terms, see /license.txt */

/**
 * Dropbox module for Chamilo
 * Classes for the dropbox module.
 *
 * 3 classes have been defined:
 * - Dropbox_Work:
 *        . id
 *        . uploader_id    => who sent it
 *        . filename        => name of file stored on the server
 *        . filesize
 *        . title            => name of file returned to user. This is the original name of the file
 *                            except when the original name contained spaces. In that case the spaces
 *                            will be replaced by _
 *        . description
 *        . author
 *        . upload_date    => date when file was first sent
 *        . last_upload_date => date when file was last sent
 *    . isOldWork    => has the work already been uploaded before
 *
 *      . feedback_date  => date of most recent feedback
 *      . feedback      => feedback text (or HTML?)
 *
 * - Dropbox_SentWork extends Dropbox_Work
 *        . recipients    => array of ["id"]["name"] lists the recipients of the work
 *
 * - Dropbox_Person:
 *        . userId
 *        . receivedWork    => array of Dropbox_Work objects
 *        . sentWork        => array of Dropbox_SentWork objects
 *        . isCourseTutor
 *        . isCourseAdmin
 *        . _orderBy        => private property used for determining the field by which the works have to be ordered
 *
 * @version 1.30
 *
 * @copyright 2004
 * @author Jan Bols <jan@ivpv.UGent.be>
 * with contributions by René Haentjens <rene.haentjens@UGent.be>
 */
class Dropbox_Work
{
    public $id;
    public $uploader_id;
    public $filename;
    public $filesize;
    public $title;
    public $description;
    public $author;
    public $upload_date;
    public $last_upload_date;
    public $isOldWork;
    public $feedback_date;
    public $feedback;

    /**
     * Constructor calls private functions to create a new work or retreive an existing work from DB
     * depending on the number of parameters.
     *
     * @param int    $arg1
     * @param string $arg2
     * @param string $arg3
     * @param string $arg4
     * @param string $arg5
     * @param int    $arg6
     */
    public function __construct($arg1, $arg2 = null, $arg3 = null, $arg4 = null, $arg5 = null, $arg6 = null)
    {
        if (func_num_args() > 1) {
            $this->createNewWork($arg1, $arg2, $arg3, $arg4, $arg5, $arg6);
        } else {
            $this->createExistingWork($arg1);
        }
    }

    /**
     * private function creating a new work object.
     *
     * @param int    $uploader_id
     * @param string $title
     * @param string $description
     * @param string $author
     * @param string $filename
     * @param int    $filesize
     *
     * @todo    $author was originally a field but this has now been replaced by the first and lastname of the uploader (to prevent anonymous uploads)
     *            As a consequence this parameter can be removed
     */
    public function createNewWork($uploader_id, $title, $description, $author, $filename, $filesize)
    {
        // Fill in the properties
        $this->uploader_id = (int) $uploader_id;
        $this->filename = $filename;
        $this->filesize = $filesize;
        $this->title = $title;
        $this->description = $description;
        $this->author = $author;
        $this->last_upload_date = api_get_utc_datetime();
        $course_id = api_get_course_int_id();

        // Check if object exists already. If it does, the old object is used
        // with updated information (authors, description, upload_date)
        $this->isOldWork = false;
        $sql = 'SELECT id, upload_date
                FROM '.Database::get_course_table(TABLE_DROPBOX_FILE)."
                WHERE
                    c_id = $course_id AND
                    filename = '".Database::escape_string($this->filename)."'";
        $result = Database::query($sql);
        $res = Database::fetch_array($result);
        if ($res) {
            $this->isOldWork = true;
        }
        // Insert or update the dropbox_file table and set the id property
        if ($this->isOldWork) {
            $this->id = $res['id'];
            $this->upload_date = $res['upload_date'];

            $params = [
                'filesize' => $this->filesize,
                'title' => $this->title,
                'description' => $this->description,
                'author' => $this->author,
                'last_upload_date' => $this->last_upload_date,
                'session_id' => api_get_session_id(),
            ];

            Database::update(
                Database::get_course_table(TABLE_DROPBOX_FILE),
                $params,
                ['c_id = ? AND id = ?' => [$course_id, $this->id]]
            );
        } else {
            $this->upload_date = $this->last_upload_date;
            $params = [
                'c_id' => $course_id,
                'uploader_id' => $this->uploader_id,
                'filename' => $this->filename,
                'filesize' => $this->filesize,
                'title' => $this->title,
                'description' => $this->description,
                'author' => $this->author,
                'upload_date' => $this->upload_date,
                'last_upload_date' => $this->last_upload_date,
                'session_id' => api_get_session_id(),
                'cat_id' => 0,
            ];

            $this->id = Database::insert(Database::get_course_table(TABLE_DROPBOX_FILE), $params);
            if ($this->id) {
                $sql = 'UPDATE '.Database::get_course_table(TABLE_DROPBOX_FILE)." SET id = iid
                        WHERE iid = {$this->id}";
                Database::query($sql);
            }
        }

        $sql = 'SELECT count(file_id) as count
                FROM '.Database::get_course_table(TABLE_DROPBOX_PERSON)."
                WHERE c_id = $course_id AND file_id = ".intval($this->id).' AND user_id = '.$this->uploader_id;
        $result = Database::query($sql);
        $row = Database::fetch_array($result);
        if (0 == $row['count']) {
            // Insert entries into person table
            $sql = 'INSERT INTO '.Database::get_course_table(TABLE_DROPBOX_PERSON)." (c_id, file_id, user_id)
                    VALUES ($course_id, ".intval($this->id).' , '.intval($this->uploader_id).')';
            Database::query($sql);
        }
    }

    /**
     * private function creating existing object by retreiving info from db.
     *
     * @param int $id
     */
    public function createExistingWork($id)
    {
        $course_id = api_get_course_int_id();
        $action = isset($_GET['action']) ? $_GET['action'] : null;

        // Do some sanity checks
        $id = intval($id);

        // Get the data from DB
        $sql = 'SELECT uploader_id, filename, filesize, title, description, author, upload_date, last_upload_date, cat_id
                FROM '.Database::get_course_table(TABLE_DROPBOX_FILE)."
                WHERE c_id = $course_id AND id = ".$id.'';
        $result = Database::query($sql);
        $res = Database::fetch_assoc($result);

        // Check if uploader is still in Chamilo system
        $uploader_id = stripslashes($res['uploader_id']);
        $userInfo = api_get_user_info($uploader_id);
        if (!$userInfo) {
            //deleted user
            $this->uploader_id = -1;
        } else {
            $this->uploader_id = $uploader_id;
        }

        // Fill in properties
        $this->id = $id;
        $this->filename = stripslashes($res['filename']);
        $this->filesize = stripslashes($res['filesize']);
        $this->title = stripslashes($res['title']);
        $this->description = stripslashes($res['description']);
        $this->author = stripslashes($res['author']);
        $this->upload_date = stripslashes($res['upload_date']);
        $this->last_upload_date = stripslashes($res['last_upload_date']);
        $this->category = $res['cat_id'];

        // Getting the feedback on the work.
        if ('viewfeedback' == $action && $this->id == $_GET['id']) {
            $feedback2 = [];
            $sql = 'SELECT * FROM '.Database::get_course_table(TABLE_DROPBOX_FEEDBACK)."
                    WHERE c_id = $course_id AND file_id='".$id."'
                    ORDER BY feedback_id ASC";
            $result = Database::query($sql);
            while ($row_feedback = Database::fetch_array($result)) {
                $row_feedback['feedback'] = Security::remove_XSS($row_feedback['feedback']);
                $feedback2[] = $row_feedback;
            }
            $this->feedback2 = $feedback2;
        }
    }

    /**
     * @return bool
     */
    public function updateFile()
    {
        $course_id = api_get_course_int_id();
        if (empty($this->id) || empty($course_id)) {
            return false;
        }

        $params = [
            'uploader_id' => $this->uploader_id,
            'filename' => $this->filename,
            'filesize' => $this->filesize,
            'title' => $this->title,
            'description' => $this->description,
            'author' => $this->author,
            'upload_date' => $this->upload_date,
            'last_upload_date' => $this->last_upload_date,
            'session_id' => api_get_session_id(),
        ];

        Database::update(
            Database::get_course_table(TABLE_DROPBOX_FILE),
            $params,
            ['c_id = ? AND id = ?' => [$course_id, $this->id]]
        );

        return true;
    }
}

class Dropbox_SentWork extends Dropbox_Work
{
    public $recipients; //array of ['id']['name'] arrays

    /**
     * Constructor calls private functions to create a new work or retreive an existing work from DB
     * depending on the number of parameters.
     *
     * @param int    $arg1
     * @param string $arg2
     * @param string $arg3
     * @param string $arg4
     * @param string $arg5
     * @param int    $arg6
     * @param array  $arg7
     */
    public function __construct($arg1, $arg2 = null, $arg3 = null, $arg4 = null, $arg5 = null, $arg6 = null, $arg7 = null)
    {
        if (func_num_args() > 1) {
            $this->createNewSentWork($arg1, $arg2, $arg3, $arg4, $arg5, $arg6, $arg7);
        } else {
            $this->createExistingSentWork($arg1);
        }
    }

    /**
     * private function creating a new SentWork object.
     *
     * @param int    $uploader_id
     * @param string $title
     * @param string $description
     * @param string $author
     * @param string $filename
     * @param int    $filesize
     * @param array  $recipient_ids
     */
    public function createNewSentWork($uploader_id, $title, $description, $author, $filename, $filesize, $recipient_ids)
    {
        $_course = api_get_course_info();

        // Call constructor of Dropbox_Work object
        parent::__construct(
            $uploader_id,
            $title,
            $description,
            $author,
            $filename,
            $filesize
        );

        $course_id = api_get_course_int_id();

        // Do sanity checks on recipient_ids array & property fillin
        // The sanity check for ex-coursemembers is already done in base constructor
        $uploader_id = (int) $uploader_id;

        $justSubmit = false;
        if (is_int($recipient_ids)) {
            $justSubmit = true;
            $recipient_ids = [$recipient_ids + $this->id];
        } elseif (0 == count($recipient_ids)) {
            $justSubmit = true;
            $recipient_ids = [$uploader_id];
        }

        if (!is_array($recipient_ids) || 0 == count($recipient_ids)) {
            exit(get_lang('An error has occurred. Please contact your system administrator.').' (code 209)');
        }

        foreach ($recipient_ids as $rec) {
            if (empty($rec)) {
                continue;
            }

            //this check is done when validating submitted data
            $this->recipients[] = ['id' => $rec];
        }

        $table_post = Database::get_course_table(TABLE_DROPBOX_POST);
        $table_person = Database::get_course_table(TABLE_DROPBOX_PERSON);
        $session_id = api_get_session_id();
        $user = api_get_user_id();
        $now = api_get_utc_datetime();
        $mailId = get_mail_id_base();

        // Insert data in dropbox_post and dropbox_person table for each recipient
        foreach ($this->recipients as $rec) {
            $file_id = (int) $this->id;
            $user_id = (int) $rec['id'];
            $sql = "INSERT INTO $table_post (c_id, file_id, dest_user_id, session_id, feedback_date, cat_id)
                    VALUES ($course_id, $file_id, $user_id, $session_id, '$now', 0)";
            Database::query($sql);
            // If work already exists no error is generated

            /*
             * Poster is already added when work is created - not so good to split logic.
             */
            if ($user_id != $user) {
                // Insert entries into person table
                $sql = "INSERT INTO $table_person (c_id, file_id, user_id)
                        VALUES ($course_id, $file_id, $user_id)";

                // Do not add recipient in person table if mailing zip or just upload.
                if (!$justSubmit) {
                    Database::query($sql); // If work already exists no error is generated
                }
            }

            // Update item_property table for each recipient
            if (($ownerid = $this->uploader_id) > $mailId) {
                $ownerid = getUserOwningThisMailing($ownerid);
            }
            if (($recipid = $rec['id']) > $mailId) {
                $recipid = $ownerid; // mailing file recipient = mailing id, not a person
            }
            api_item_property_update(
                $_course,
                TOOL_DROPBOX,
                $this->id,
                'DropboxFileAdded',
                $ownerid,
                null,
                $recipid
            );
        }
    }

    /**
     * private function creating existing object by retreiving info from db.
     *
     * @param int $id
     */
    public function createExistingSentWork($id)
    {
        $id = (int) $id;
        $course_id = api_get_course_int_id();

        // Call constructor of Dropbox_Work object
        parent::__construct($id);

        // Fill in recipients array
        $this->recipients = [];
        $sql = 'SELECT dest_user_id, feedback_date, feedback
                FROM '.Database::get_course_table(TABLE_DROPBOX_POST)."
                WHERE c_id = $course_id AND file_id = ".intval($id);
        $result = Database::query($sql);
        while ($res = Database::fetch_assoc($result)) {
            // Check for deleted users
            $dest_user_id = $res['dest_user_id'];
            $user_info = api_get_user_info($dest_user_id);
            if (!$user_info) {
                $this->recipients[] = ['id' => -1, 'name' => get_lang('Unknown')];
            } else {
                $this->recipients[] = [
                    'id' => $dest_user_id,
                    'name' => $user_info['complete_name'],
                    'user_id' => $dest_user_id,
                    'feedback_date' => $res['feedback_date'],
                    'feedback' => $res['feedback'],
                ];
            }
        }
    }
}

class Dropbox_Person
{
    // The receivedWork and the sentWork arrays are sorted.
    public $receivedWork; // an array of Dropbox_Work objects
    public $sentWork; // an array of Dropbox_SentWork objects

    public $userId = 0;
    public $isCourseAdmin = false;
    public $isCourseTutor = false;
    public $_orderBy = ''; // private property that determines by which field

    /**
     * Constructor for recreating the Dropbox_Person object.
     *
     * @param int  $userId
     * @param bool $isCourseAdmin
     * @param bool $isCourseTutor
     */
    public function __construct($userId, $isCourseAdmin, $isCourseTutor)
    {
        $course_id = api_get_course_int_id();

        // Fill in properties
        $this->userId = $userId;
        $this->isCourseAdmin = $isCourseAdmin;
        $this->isCourseTutor = $isCourseTutor;
        $this->receivedWork = [];
        $this->sentWork = [];

        // Note: perhaps include an ex coursemember check to delete old files

        $session_id = api_get_session_id();
        $condition_session = api_get_session_condition($session_id);

        $post_tbl = Database::get_course_table(TABLE_DROPBOX_POST);
        $person_tbl = Database::get_course_table(TABLE_DROPBOX_PERSON);
        $file_tbl = Database::get_course_table(TABLE_DROPBOX_FILE);

        // Find all entries where this person is the recipient
        $sql = "SELECT DISTINCT r.file_id, r.cat_id
                FROM $post_tbl r
                INNER JOIN $person_tbl p
                ON (r.file_id = p.file_id AND r.c_id = p.c_id)
                WHERE
                     r.c_id = $course_id AND
                     p.user_id = ".intval($this->userId).' AND
                     r.dest_user_id = '.intval($this->userId)." $condition_session ";

        $result = Database::query($sql);
        while ($res = Database::fetch_array($result)) {
            $temp = new Dropbox_Work($res['file_id']);
            $temp->category = $res['cat_id'];
            $this->receivedWork[] = $temp;
        }
        // Find all entries where this person is the sender/uploader
        $sql = "SELECT DISTINCT f.iid
                FROM $file_tbl f
                INNER JOIN $person_tbl p
                ON (f.iid = p.file_id AND f.c_id = p.c_id)
                WHERE
                    f.c_id = $course_id AND
                    f.uploader_id   = ".intval($this->userId).' AND
                    p.user_id       = '.intval($this->userId)."
                    $condition_session
                ";
        $result = Database::query($sql);
        while ($res = Database::fetch_array($result)) {
            $this->sentWork[] = new Dropbox_SentWork($res['iid']);
        }
    }

    /**
     * Deletes all the received categories and work of this person.
     *
     * @param int $id
     *
     * @return bool
     */
    public function deleteReceivedWorkFolder($id)
    {
        $course_id = api_get_course_int_id();

        $id = intval($id);
        $sql = 'DELETE FROM '.Database::get_course_table(TABLE_DROPBOX_FILE)."
                WHERE c_id = $course_id AND cat_id = '".$id."' ";
        Database::query($sql);

        $sql = 'DELETE FROM '.Database::get_course_table(TABLE_DROPBOX_CATEGORY)."
                WHERE c_id = $course_id AND cat_id = '".$id."' ";
        Database::query($sql);

        $sql = 'DELETE FROM '.Database::get_course_table(TABLE_DROPBOX_POST)."
                WHERE c_id = $course_id AND cat_id = '".$id."' ";
        Database::query($sql);

        return true;
    }

    /**
     * Deletes a received dropbox file of this person with id=$id.
     *
     * @param int $id
     */
    public function deleteReceivedWork($id)
    {
        $course_id = api_get_course_int_id();
        $id = (int) $id;

        // index check
        $found = false;
        foreach ($this->receivedWork as $w) {
            if ($w->id == $id) {
                $found = true;
                break;
            }
        }

        if (!$found) {
            if (!$this->deleteReceivedWorkFolder($id)) {
                exit(get_lang('An error has occurred. Please contact your system administrator.').' (code 216)');
            }
        }
        // Delete entries in person table concerning received works
        $sql = "DELETE FROM ".Database::get_course_table(TABLE_DROPBOX_PERSON)."
                WHERE c_id = $course_id AND user_id = '".$this->userId."' AND file_id ='".$id."'";
        Database::query($sql);
        removeUnusedFiles(); // Check for unused files
    }

    /**
     * Deletes a sent dropbox file of this person with id=$id.
     *
     * @param int $id
     */
    public function deleteSentWork($id)
    {
        $course_id = api_get_course_int_id();

        $id = (int) $id;

        // index check
        $found = false;
        foreach ($this->sentWork as $w) {
            if ($w->id == $id) {
                $found = true;
                break;
            }
        }
        if (!$found) {
            if (!$this->deleteReceivedWorkFolder($id)) {
                exit(get_lang('An error has occurred. Please contact your system administrator.').' (code 219)');
            }
        }
        //$file_id = $this->sentWork[$index]->id;
        // Delete entries in person table concerning sent works
        $sql = 'DELETE FROM '.Database::get_course_table(TABLE_DROPBOX_PERSON)."
                WHERE c_id = $course_id AND user_id='".$this->userId."' AND file_id='".$id."'";
        Database::query($sql);
        removeMoreIfMailing($id);
        removeUnusedFiles(); // Check for unused files
    }
}
