<?php
# -*- coding: utf-8 -*-
/*
    NanoKubbe
    Copyleft (C) 2006-2009 BohwaZ - http://bohwaz.net/

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as
    published by the Free Software Foundation, version 3 of the
    License.

    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 Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

class nkException extends Exception { }
class nkPluginException extends nkException { }
class nkUserException extends nkException { }
class nkTemplateException extends nkException { }

class NanoKubbe
{
    const VERSION = '2.0.0';

    const COMMENT_CONTEXT_COMMENT = 0;
    const COMMENT_CONTEXT_PAGE = 1;
    const COMMENT_CONTEXT_MEDIA = 2;

    const URL_CONTEXT_HISTORY = 'history';
    const URL_CONTEXT_COMMENTS = 'comments';

    static private $instance = null;

    private $sessions_started = false;

    static protected $datas = false;
    private $plugins = false;

    static private $signals = array(
        'url.call',
        'url.notfound',

        'page.create.before',
        'page.edit.before',
        'page.delete.before',
        'page.create.after',
        'page.edit.after',
        'page.delete.after',

        'comment.add.before',
        'comment.delete.before',
        'comment.add.after',
        'comment.delete.after',

        'media.create.before',
        'media.edit.before',
        'media.publish.before',
        'media.delete.before',
        'media.create.after',
        'media.edit.after',
        'media.publish.after',
        'media.delete.after',
    );

    public $allowed_html = array(
        // Inline
        'strong'=> array('class'),
        'em'    => array('class'),
        'sup'   => array('class'),
        'sub'   => array('class'),
        'span'  => array('class'),
        'abbr'  => array('class', 'title'),
        'acronym' => array('class', 'title'),
        'a'     => array('class', 'href', 'title'),
        'code'  => array('class'),
        'cite'  => array('class'),
        'del'   => array('class'),
        'ins'   => array('class'),
        'kbd'   => array('class'),
        'samp'  => array('class'),
        'br'    => array(),

        // Block
        'div'   => array('class', 'id'),
        'p'     => array('class'),
        'blockquote' => array('class'),
        'ul'    => array('class'),
        'li'    => array('class'),
        'ol'    => array('class'),
        'h1'    => array('class', 'id'),
        'h2'    => array('class', 'id'),
        'h3'    => array('class', 'id'),
        'h4'    => array('class'),
        'h5'    => array('class'),
        'h6'    => array('class'),
        'pre'   => array('class'),
        'dl'    => array('class'),
        'dt'    => array('class'),
        'dd'    => array('class'),
        'hr'    => array('class'),

        // Table elements
        'table' => array('class'),
        'caption' => array('class'),
        'thead' => array('class'),
        'tbody' => array('class'),
        'tfoot' => array('class'),
        'tr'    => array('class'),
        'td'    => array('class', 'rowspan', 'colspan'),
        'th'    => array('class', 'rowspan', 'colspan'),

        // Media elements
        'img'   => array('class', 'src', 'alt', 'width', 'height', 'title'),
        'object'=> array('class', 'width', 'height', 'title', 'type', 'data'),
        'param' => array('name', 'value'),
        'embed' => array('src', 'type', 'width', 'height'),

        );

    public function __construct()
    {
        $init = false;

        if (!file_exists(DATAS_PATH . '/datas.db'))
            $init = true;

        self::$datas = new SQLiteDatabase(DATAS_PATH . '/datas.db', 0600);
        $this->plugins = new SQLiteDatabase(DATAS_PATH . '/plugins.db', 0600);

        if ($init)
        {
            try {
                $this->initDatas();
            }
            catch (nkException $e)
            {
                unlink(DATAS_PATH . '/datas.db');
                unlink(DATAS_PATH . '/plugins.db');
                throw $e;
            }
        }

        self::$instance = $this;
    }

    static public function &instance()
    {
        if (!self::$instance)
            new NanoKubbe;

        return self::$instance;
    }

    private function initDatas()
    {
        $sql = file_get_contents(BASE_PATH . '/include/datas-db-scheme.txt');
        $sql = preg_replace('!(#|//).*!', '', $sql); // Deleting comments
        self::$datas->queryExec($sql);

        $sql = file_get_contents(BASE_PATH . '/include/plugins-db-scheme.txt');
        $sql = preg_replace('!(#|//).*!', '', $sql); // Deleting comments
        $this->plugins->queryExec($sql);

        $dirs = array('plugins', 'pages', 'comments', 'medias');

        for ($i = 0; $i < 99; $i++)
        {
            $nb = $i < 10 ? '0' . $i : $i;
            $dirs[] = 'pages/' . $nb;
            $dirs[] = 'comments/' . $nb;
            $dirs[] = 'medias/' . $nb;
        }

        foreach ($dirs as $dir)
        {
            if (!file_exists(DATAS_PATH . '/' . $dir))
                mkdir(DATAS_PATH . '/' . $dir);

            if (!is_writeable(DATAS_PATH . '/' . $dir))
                throw new nkException("Application can't write to " . DATAS_PATH . '/' . $dir);
        }

        $this->createPage('My home', 'en', '_home');

        return true;
    }

    /************************************************************************************************
     ** PLUGINS MANAGEMENT **
     */
    static private function getPluginPath($name, $file=null)
    {
        $path = DATAS_PATH . '/plugins/' . $name;

        if (!is_null($file))
        {
            $path .= '/' . $file;
        }

        return $path;
    }

    public function emitSignal($signal, $args = array())
    {
        $res = $this->plugins->arrayQuery('SELECT plugin, file, callback FROM signals
            WHERE signal = \'' . sqlite_escape_string($signal) . '\' ORDER BY plugin;', SQLITE_ASSOC);

        if (empty($res))
            return false;

        array_unshift($args, $this);

        foreach ($res as $row)
        {
            require_once self::getPluginPath($row['plugin'], $row['file']);

            if (!empty($row['callback']))
            {
                if (strpos($row['callback'], '::') !== false)
                {
                    $row['callback'] = explode('::', $row['callback']);
                }

                if (call_user_func_array($row['callback'], $args))
                {
                    return true;
                }
            }
        }

        return false;
    }

    public function registerPlugin($plugin)
    {
        $signals = self::getPluginPath($plugin, 'signals.cfg');
        $signals_to_add = array();

        if (file_exists($signals))
        {
            $signals = file($signals);

            foreach ($signals as $signal)
            {
                list($signal, $file, $callback) = explode(';', $signal);

                $signal = trim($signal);
                $file = trim($file);
                $callback = trim($callback);

                if (!in_array($signal, self::$signals))
                    throw new nkPluginException("Unknow signal '{$signal}'.");

                if (!preg_match('!^(?:[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*::)?[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*$!', $callback)
                    || !is_callable($callback, true))
                    throw new nkPluginException("Invalid callback '{$callback}' for signal {$signal}.");

                if (!file_exists(self::getPluginPath($plugin, $file)))
                    throw new nkPluginException("Non-existent file '{$file}' for signal {$signal}.");

                $signals_to_add[] = array($signal, $file, $callback);
            }
        }

        $this->plugins->unbufferedQuery('DELETE FROM signals WHERE plugin = \''.sqlite_escape_string($plugin).'\';');

        foreach ($signals_to_add as $signal)
        {
            list($signal, $file, $callback) = $signal;
            $this->plugins->unbufferedQuery('INSERT INTO signals (plugin, signal, file, callback)
                VALUES (\''.sqlite_escape_string($plugin).'\', \''.sqlite_escape_string($signal).'\',
                    \''.sqlite_escape_string($file).'\', \''.sqlite_escape_string($callback).'\');');
        }

        return true;
    }

    /***********************************************************************************************
     ** USER MANAGEMENT **
     */
    private function _startSession()
    {
        if(!$this->sessions_started)
        {
            @session_start();
            $this->sessions_started = true;
        }
    }

    public function login($login, $password)
    {
        if ($login != $this->getConfig('login'))
            return false;

        if ($password != $this->getConfig('password'))
            return false;

        $this->_startSession();

        $_SESSION['is_logged'] = true;
        return true;
    }

    public function isLogged()
    {
        $this->_startSession();

        if(!empty($_SESSION['is_logged']))
            return true;

        return false;
    }

    public function logout()
    {
        $this->_startSession();

        $_SESSION = array();
        session_write_close();

        return true;
    }

    public function getConfig($key)
    {
        $res = self::$datas->arrayQuery('SELECT type, value FROM config WHERE key=\''.sqlite_escape_string($key).'\';', SQLITE_ASSOC);

        if (empty($res[0]))
            return null;

        switch ($res[0]['type'])
        {
            case 'int':
                return (int) $res[0]['value'];
            case 'bool':
                return (bool) $res[0]['value'];
            default:
                return (string) $res[0]['value'];
        }
    }

    public function setConfig($key, $value)
    {
        $res = self::$datas->arrayQuery('SELECT type FROM config WHERE key=\''.sqlite_escape_string($key).'\';', SQLITE_ASSOC);

        if (empty($res[0]))
            throw new nkException('Unable to set illegal config key '.$key);

        self::$datas->unbufferedQuery('UPDATE config SET value=\''.sqlite_escape_string($value).'\' WHERE key=\''.sqlite_escape_string($key).'\';');
        return true;
    }

    private function getRevisionFilename($id, $rev)
    {
        return DATAS_PATH . '/pages/' . substr($id, -2) . '/' . $id . '/r' . $rev . '.txt';
    }

    public function getPagesIdsFromUri($uri)
    {
        $res = self::$datas->arrayQuery('SELECT id, lang FROM pages WHERE uri = \''.sqlite_escape_string($uri).'\';', SQLITE_ASSOC);

        $pages = array();

        foreach ($res as $row)
        {
            $pages[$row['lang']] = $row['id'];
        }

        return $pages;
    }

    public function isValidPageUri($uri)
    {
        if (preg_match('!^[A-Za-z0-9_-]+$!', $uri))
            return true;
        else
            return false;
    }

    public function checkPageUri($id=false, $uri, $lang)
    {
        $pages = $this->getPagesIdsFromUri($uri);

        if (isset($pages[$lang]) && (!$id || $pages[$lang] != $id))
        {
            return false;
        }

        return true;
    }

    public function checkPageExist($id)
    {
        $res = self::$datas->arrayQuery('SELECT 1 FROM pages WHERE id = \''.(int)$id.'\';', SQLITE_NUM);
        return !empty($res[0][0]) ? true : false;
    }

    public function getPage($id, $rev=0)
    {
        $res = self::$datas->arrayQuery('SELECT * FROM pages WHERE id = \''.(int)$id.'\';', SQLITE_ASSOC);

        if (empty($res))
            return false;

        $page =& $res[0];

        if (empty($rev))
            $rev = $page['revision'];

        if ($rev > 0)
            $page['content'] = file_get_contents($this->getRevisionFilename($id, $rev));
        else
            $page['content'] = '';

        return $page;
    }

    public function getPageRevisionsList($id)
    {
        $res = self::$datas->arrayQuery('SELECT * FROM revisions WHERE page = \''.(int)$id.'\' ORDER BY id DESC;', SQLITE_ASSOC);
        return empty($res) ? false : $res;
    }

    public function createPage($title, $lang, $uri='', $online=true)
    {
        $this->emitSignal('page.create.before', array(&$title, &$lang, &$uri));

        if (empty($uri))
            $uri = utils::makeUriFromTitle($title);
        else
            $uri = utils::makeUriFromTitle($uri);

        if (!$this->checkPageUri(false, $uri, $lang))
            $uri = utils::id2url(time()) . '-' . $uri;

        if ($uri == '_home')
            $id = '100';
        else
            $id = 'NULL';

        self::$datas->unbufferedQuery('INSERT INTO pages (id, title, uri, date_create, date_update, year, month, day, lang, status) VALUES
            ('.$id.', \''.sqlite_escape_string($title).'\', \''.sqlite_escape_string($uri).'\', \''.time().'\', \''.time().'\',
            \''.date('Y').'\', \''.date('m').'\', \''.date('d').'\', \''.sqlite_escape_string($lang).'\', \''.(int)$online.'\');');

        $id = self::$datas->lastInsertRowid();

        mkdir(DATAS_PATH . '/pages/' . substr($id, -2) . '/' . $id);

        $this->emitSignal('page.create.after', array(&$title, &$lang, &$uri, &$id));

        return array($id, $uri);
    }

    public function editPage($id, $page, $comment='')
    {
        $this->emitSignal('page.edit.before', array(&$id, &$page, &$comment));

        if (empty($page['uri']))
        {
            $page['uri'] = $page['title'];
        }

        $page['uri'] = utils::makeUriFromTitle($page['uri']);

        if (!$this->checkPageUri($id, $page['uri'], $page['lang']))
            $uri = utils::id2url($id) . '-' . $page['uri'];

        $page['content'] = trim($page['content']);

        $current = $this->getPage($id);

        if ($current['content'] == $page['content'])
            $page['revision'] = $current['revision'];
        else
            $page['revision'] = $current['revision'] + 1;

        self::$datas->unbufferedQuery('UPDATE pages SET
            title = \''.sqlite_escape_string($page['title']).'\',
            uri = \''.sqlite_escape_string($page['uri']).'\',
            revision = \''.sqlite_escape_string($page['revision']).'\',
            parent = \''.(int)$page['parent'].'\',
            allow_comments = \''.(int)$page['allow_comments'].'\',
            lang = \''.sqlite_escape_string($page['lang']).'\',
            date_update = \''.time().'\',
            status = \''.(int)$page['status'].'\'
            WHERE id = \''.(int)$id.'\';');

        if ($page['revision'] != $current['revision'])
        {
            file_put_contents($this->getRevisionFilename($id, $page['revision']), $page['content']);

            $diff = strlen($current['content']) - strlen($page['content']);
            if ($diff > 0) $diff = '+' . $diff;

            self::$datas->unbufferedQuery('INSERT INTO revisions (page, id, date, comment, changed) VALUES
                (\''.(int)$id.'\', \''.(int)$page['revision'].'\', \''.time().'\',
                \''.sqlite_escape_string($comment).'\', \''.sqlite_escape_string($diff).'\');');
        }

        $this->emitSignal('page.edit.after', array(&$id, &$page, &$comment));

        return true;
    }

    public function deletePage($id)
    {
        $this->emitSignal('page.delete.before', array(&$id));

        utils::recursiveDelete(DATAS_PATH . '/pages/' . substr($id, -2) . '/' . $id);
        self::$datas->unbufferedQuery('DELETE FROM revisions WHERE page = \''.(int)$id.'\';');
        self::$datas->unbufferedQuery('DELETE FROM comments WHERE parent = \''.(int)$id.'\' AND context = \''.NanoKubbe::COMMENT_CONTEXT_PAGE.'\';');
        self::$datas->unbufferedQuery('DELETE FROM medias WHERE page = \''.(int)$id.'\';');
        self::$datas->unbufferedQuery('DELETE FROM pages WHERE parent = \''.(int)$id.'\';');
        self::$datas->unbufferedQuery('DELETE FROM pages WHERE id = \''.(int)$id.'\';');

        $this->emitSignal('page.delete.after', array(&$id));

        return true;
    }

    public function getPagesCount($parent=0)
    {
        $res = self::$datas->arrayQuery('SELECT COUNT(id) FROM pages WHERE parent=\''.(int)$parent.'\';', SQLITE_NUM);
        return $res[0][0];
    }

    public function getPagesList($order=false, $parent=0, $begin=0, $limit=50)
    {
        if ($order == self::BY_LAST_UPDATE)
            $o = 'date_update DESC';
        elseif ($order == self::BY_CREATION)
            $o = 'date_create DESC';
        else
            $o = 'title ASC';

        return self::$datas->arrayQuery('SELECT * FROM pages WHERE parent=\''.(int)$parent.'\' ORDER BY '.$o.' LIMIT '.(int)$begin.','.(int)$limit.';', SQLITE_ASSOC);
    }

    //public function getPagesListByLang()

    public function getPageHistoryUrl($id)
    {
        return $this->getPageUrl($id, null, null, self::URL_CONTEXT_HISTORY);
    }

    public function getPageUrl($id=null, $uri=null, $lang=null, $last=null)
    {
        $url = utils::getBaseUrl();

        if (($uri == '_home' || !$id) && !$uri && !$lang && !$last)
            return $url;

        if ($id)
            $url.= '-'.utils::id2url($id).'-/';

        if ($uri)
            $url.= $uri . '/';

        if ($lang)
            $url.= $lang . '/';

        if (is_int($last) && $last > 0)
        {
            $url.= 'r'.(int)$last;
        }
        elseif (is_string($last))
        {
            if ($last == self::URL_CONTEXT_HISTORY)
            {
                $url .= 'history';
            }
            elseif ($last == self::URL_CONTEXT_COMMENTS)
            {
                $url .= 'comments';
            }
        }

        return $url;
    }

    public function getMimeType($ext)
    {
        switch ($ext)
        {
            case 'css':
                return 'text/css';
            case 'csv':
                return 'text/comma-separated-values';
            case 'html':
            case 'htm':
            case 'xhtml':
            case 'tpl':
                return 'text/html';
            case 'jpeg':
            case 'jpe':
            case 'jpg':
                return 'image/jpeg';
            case 'gif':
                return 'image/gif';
            case 'png':
                return 'image/png';
            case 'mng':
                return 'image/mng';
            case 'svg':
                return 'image/svg+xml';
            case 'php':
            case 'php3':
            case 'phtml':
                return 'text/plain';
            case 'mp3':
                return 'audio/mp3';
            case 'ogg':
                return 'audio/x-ogg';
            case 'ogm':
                return 'application/x-ogg';
            case 'avi':
                return 'video/avi';
            case 'pdf':
                return 'application/pdg';
            case 'txt':
                return 'text/plain';
            case 'js':
                return 'text/javascript';
            default:
                return 'unknown';
        }
    }

}

?>