<?php
// $Id: pnMod.php,v 1.42.2.1 2002/03/28 09:48:13 jgm Exp $
// ----------------------------------------------------------------------
// POST-NUKE Content Management System
// Copyright (C) 2001 by the Post-Nuke Development Team.
// http://www.postnuke.com/
// ----------------------------------------------------------------------
// Based on:
// PHP-NUKE Web Portal System - http://phpnuke.org/
// Thatware - http://thatware.org/
// ----------------------------------------------------------------------
// LICENSE
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License (GPL)
// as published by the Free Software Foundation; either version 2
// 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.
//
// To read the license please visit http://www.gnu.org/copyleft/gpl.html
// ----------------------------------------------------------------------
// Original Author of file: Jim McDonald
// Purpose of file: Module variable handling
// ----------------------------------------------------------------------

/*
 * pnModGetVar - get a module variable
 * Takes two parameters:
 * - the name of the module
 * - the name of the variable
 */
function pnModGetVar($modname, $name)
{
    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

    if ((empty($modname)) || (empty($name))) {
        return false;
    }

    $modulevarstable = $pntable['module_vars'];
    $modulevarscolumn = &$pntable['module_vars_column'];
    $query = "SELECT $modulevarscolumn[value]
              FROM $modulevarstable
              WHERE $modulevarscolumn[modname] = '" . pnVarPrepForStore($modname) . "'
              AND $modulevarscolumn[name] = '" . pnVarPrepForStore($name) . "'";
    $result = $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    if ($result->EOF) {
        return;
    }

    list($value) = $result->fields;
    $result->Close();

    return $value;
}

/*
 * pnModSetVar - set a module variable
 * Takes three parameters:
 * - the name of the module
 * - the name of the variable
 * - the value of the variable
 */
function pnModSetVar($modname, $name, $value)
{
    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

    if ((empty($modname)) || (empty($name))) {
        return false;
    }

    $curvar = pnModGetVar($modname, $name);

    $modulevarstable = $pntable['module_vars'];
    $modulevarscolumn = &$pntable['module_vars_column'];
    if (!isset($curvar)) {
        $query = "INSERT INTO $modulevarstable
                     ($modulevarscolumn[modname],
                      $modulevarscolumn[name],
                      $modulevarscolumn[value])
                  VALUES
                     ('" . pnVarPrepForStore($modname) . "',
                      '" . pnVarPrepForStore($name) . "',
                      '" . pnVarPrepForStore($value) . "');";
    } else {
        $query = "UPDATE $modulevarstable
                  SET $modulevarscolumn[value] = '" . pnVarPrepForStore($value) . "'
                  WHERE $modulevarscolumn[modname] = '" . pnVarPrepForStore($modname) . "'
                  AND $modulevarscolumn[name] = '" . pnVarPrepForStore($name) . "'";
    }

    $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    return true;
}


/*
 * pnModDelVar - delete a module variable
 * Takes two parameters:
 * - the name of the module
 * - the name of the variable
 */
function pnModDelVar($modname, $name)
{
    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

    if ((empty($modname)) || (empty($name))) {
        return false;
    }

    $modulevarstable = $pntable['module_vars'];
    $modulevarscolumn = &$pntable['module_vars_column'];
    $query = "DELETE FROM $modulevarstable
              WHERE $modulevarscolumn[modname] = '" . pnVarPrepForStore($modname) . "'
              AND $modulevarscolumn[name] = '" . pnVarPrepForStore($name) . "'";
    $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    return true;
}

/*
 * pnModGetIDFromName - get module ID given its name
 * Takes one parameter:
 * - the name of the module
 */
function pnModGetIDFromName($module)
{
    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

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

    $modulestable = $pntable['modules'];
    $modulescolumn = &$pntable['modules_column'];
    $query = "SELECT $modulescolumn[id]
              FROM $modulestable
              WHERE $modulescolumn[name] = '" . pnVarPrepForStore($module) . "'";
    $result = $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    if ($result->EOF) {
        return false;
    }

    list($id) = $result->fields;
    $result->Close();

    return $id;
}

/**
 * get information on module
 * @param id
 * @returns array
 * @ return array of module information or false if core ( id = 0 )
 */
function pnModGetInfo($modid)
{
    // a $modid of 0 is associated with core ( pn_blocks.mid, ... ).
    if ( $modid == 0 ) {
        return false;
    }

    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

    $modulestable = $pntable['modules'];
    $modulescolumn = &$pntable['modules_column'];
    $query = "SELECT $modulescolumn[name],
                     $modulescolumn[type],
                     $modulescolumn[directory],
                     $modulescolumn[regid],
                     $modulescolumn[displayname],
                     $modulescolumn[description],
                     $modulescolumn[version]
              FROM $modulestable
              WHERE $modulescolumn[id] = " . pnVarPrepForStore($modid);
    $result = $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    if ($result->EOF) {
        return false;
    }

    list($resarray['name'],
         $resarray['type'],
         $resarray['directory'],
         $resarray['regid'],
         $resarray['displayname'],
         $resarray['description'],
         $resarray['version']) = $result->fields;
    $result->Close();

    return $resarray;
}

/**
 * get list of user modules
 * @returns array
 * @return array of module information arrays
 */
function pnModGetUserMods()
{
    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

    $modulestable = $pntable['modules'];
    $modulescolumn = &$pntable['modules_column'];
    $query = "SELECT $modulescolumn[name],
                     $modulescolumn[type],
                     $modulescolumn[directory],
                     $modulescolumn[regid],
                     $modulescolumn[displayname],
                     $modulescolumn[description],
                     $modulescolumn[version]
              FROM $modulestable
              WHERE $modulescolumn[state] = " . _PNMODULE_STATE_ACTIVE . "
              AND $modulescolumn[user_capable] = 1
              ORDER BY $modulescolumn[name]";
    $result = $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    if ($result->EOF) {
        return false;
    }

    $resarray = array();
    while(list($name,
               $modtype,
               $directory,
               $regid,
               $displayname,
               $description,
               $version) = $result->fields) {
        $result->MoveNext();

        $tmparray = array('name' => $name,
                          'type' => $modtype,
                          'directory' => $directory,
                          'regid' => $regid,
                          'displayname' => $displayname,
                          'description' => $description,
                          'version' => $version);

        array_push($resarray, $tmparray);
    }
    $result->Close();

    return $resarray;
}

/**
 * get list of administration modules
 * @returns array
 * @return array of module information arrays
 */
function pnModGetAdminMods()
{
    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

    $modulestable = $pntable['modules'];
    $modulescolumn = &$pntable['modules_column'];

    $query = "SELECT $modulescolumn[name],
                     $modulescolumn[type],
                     $modulescolumn[directory],
                     $modulescolumn[regid],
                     $modulescolumn[displayname],
                     $modulescolumn[description],
                     $modulescolumn[version]
              FROM $modulestable
              WHERE $modulescolumn[state] = " . _PNMODULE_STATE_ACTIVE . "
              AND $modulescolumn[admin_capable] = 1
              AND $modulescolumn[directory] != 'NS-Admin'
              ORDER BY $modulescolumn[name]";

    $result = $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    if ($result->EOF) {
        return false;
    }

    $resarray = array();
    while(list($name,
               $modtype,
               $directory,
               $regid,
               $displayname,
               $description,
               $version) = $result->fields) {
        $result->MoveNext();

        $tmparray = array('name' => $name,
                          'type' => $modtype,
                          'directory' => $directory,
                          'regid' => $regid,
                          'displayname' => $displayname,
                          'description' => $description,
                          'version' => $version);

        array_push($resarray, $tmparray);
    }
    $result->Close();

    return $resarray;
}

/**
 * load an API for a module
 * @param modname - registered name of the module
 * @param type - type of functions to load
 * @returns bool
 * @return true on success, false on failure
 */
function pnModAPILoad($modname, $type='user')
{
    static $loaded = array();

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

    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

    if (!empty($loaded["$modname$type"])) {
        // Already loaded from somewhere else
        return true;
    }

    $modulestable = $pntable['modules'];
    $modulescolumn = &$pntable['modules_column'];
    $query = "SELECT $modulescolumn[name],
                     $modulescolumn[directory],
                     $modulescolumn[state]
              FROM $modulestable
              WHERE $modulescolumn[name] = '" . pnVarPrepForStore($modname) . "'";
    $result = $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    if ($result->EOF) {
        pnSessionSetVar('errmsg', "Unknown module $modname");
        return false;
    }

    list($name, $directory, $state) = $result->fields;
    $result->Close();

    list($osdirectory, $ostype) = pnVarPrepForOS($directory, $type);

    $osfile = "modules/$osdirectory/pn{$ostype}api.php";
    if (!file_exists($osfile)) {
        // File does not exist
        return false;
    }

    // Load the file
    include $osfile;
    $loaded["$modname$type"] = 1;

    // Load the module language files
    $currentlang = pnUserGetLang();
    $defaultlang = pnConfigGetVar('language');
    if (empty($defaultlang)) {
        $defaultlang = 'eng';
    }

    list($oscurrentlang, $osdefaultlang) = pnVarPrepForOS($currentlang, $defaultlang);
    if (file_exists("modules/$osdirectory/pnlang/$oscurrentlang/{$ostype}api.php")) {
        include "modules/$osdirectory/pnlang/$oscurrentlang/{$ostype}api.php";
    } elseif (file_exists("modules/$osdirectory/pnlang/$osdefaultlang/{$ostype}api.php")) {
        include "modules/$osdirectory/pnlang/$osdefaultlang/{$ostype}api.php";
    }

    // Load datbase info
    pnModDBInfoLoad($modname, $directory);

    return true;
}

/**
 * load datbase definition for a module
 * @param name - name of module to load database definition for
 * @param directory - directory that module is in (if known)
 * @returns bool
 */
function pnModDBInfoLoad($modname, $directory='')
{
    static $loaded = array();

    // Check to ensure we aren't doing this twice
    if (isset($loaded[$modname])) {
        return true;
    }

    // Get the directory if we don't already have it
    if (empty($directory)) {
        list($dbconn) = pnDBGetConn();
        $pntable = pnDBGetTables();
        $modulestable = $pntable['modules'];
        $modulescolumn = &$pntable['modules_column'];
        $sql = "SELECT $modulescolumn[directory]
                FROM $modulestable
                WHERE $modulescolumn[name] = '" . pnVarPrepForStore($modname) . "'";
        $result = $dbconn->Execute($sql);
        if($dbconn->ErrorNo() != 0) {
            return;
        }

        if ($result->EOF) {
            return false;
        }

        $directory = $result->fields[0];
        $result->Close();
    }

    // Load the database definition if required
    $ospntablefile = 'modules/' . pnVarPrepForOS($directory) . '/pntables.php';
    // Ignore errors for this, if it fails we'll find out and handle
    // it when we look for the function itself
    @include_once $ospntablefile;
    $tablefunc = $modname . '_' . 'pntables';
    if (function_exists($tablefunc)) {
        global $pntable;
        $pntable = array_merge($pntable, $tablefunc());
    }
    $loaded[$modname] = true;

    return true;
}

/**
 * load a module
 * @param name - name of module to load
 * @param type - type of functions to load
 * @returns string
 * @return name of module loaded, or false on failure
 */
function pnModLoad($modname, $type='user')
{
    static $loaded = array();

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

    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

    $modulestable = $pntable['modules'];
    $modulescolumn = &$pntable['modules_column'];

    if (!empty($loaded["$modname$type"])) {
        // Already loaded from somewhere else
        return $modname;
    }

    $query = "SELECT $modulescolumn[directory],
                     $modulescolumn[state]
              FROM $modulestable
              WHERE $modulescolumn[name] = '" . pnVarPrepForStore($modname) . "'";
    $result = $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    if ($result->EOF) {
        return false;
    }

    list($directory, $state) = $result->fields;
    $result->Close();

    // Load the module and module language files
    list($osdirectory, $ostype) = pnVarPrepForOS($directory, $type);
    $osfile = "modules/$osdirectory/pn$ostype.php";

    if (!file_exists($osfile)) {
        // File does not exist
        return false;
    }

    // Load file
    include $osfile;
    $loaded["$modname$type"] = 1;

    $defaultlang = pnConfigGetVar('language');
    if (empty($defaultlang)) {
        $defaultlang = 'eng';
    }

    $currentlang = pnUserGetLang();
    if (file_exists("modules/$osdirectory/pnlang/$currentlang/$ostype.php")) {
        include "modules/$osdirectory/pnlang/" . pnVarPrepForOS($currentlang) . "/$ostype.php";
    } elseif (file_exists("modules/$directory/pnlang/$defaultlang/$ostype.php")) {
        include "modules/$osdirectory/pnlang/" . pnVarPrepForOS($defaultlang) . "/$ostype.php";
    }

    // Load datbase info
    pnModDBInfoLoad($modname, $directory);

    // Return the module name
    return $modname;
}

/**
 * run a module API function
 * @param modname - registered name of module
 * @param type - type of function to run
 * @param func - specific function to run
 * @param args - arguments to pass to the function
 * @returns mixed
 */
function pnModAPIFunc($modname, $type='user', $func='main', $args=array())
{

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

    if (empty($type)) {
        $func = 'user';
    }
    if (empty($func)) {
        $func = 'main';
    }

    // Build function name and call function
    $modapifunc = "{$modname}_{$type}api_{$func}";
    if (function_exists($modapifunc)) {
        return $modapifunc($args);
    }

    return false;
}

/**
 * run a module function
 * @param modname - registered name of module
 * @param type - type of function to run
 * @param func - specific function to run
 * @param args - argument array
 * @returns mixed
 */
function pnModFunc($modname, $type='user', $func='main', $args=array())
{

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

    if (empty($type)) {
        $func = 'user';
    }
    if (empty($func)) {
        $func = 'main';
    }

    // Build function name and call function
    $modfunc = "{$modname}_{$type}_{$func}";
    if (function_exists($modfunc)) {
        return $modfunc($args);
    }

    return false;
}

/**
 * generate a module function URL
 * @param modname - registered name of module
 * @param type - type of function
 * @param func - module function
 * @param args - array of arguments to put on the URL
 * @returns string
 * @return absolute URL for call
 */
function pnModURL($modname, $type='user', $func='main', $args=array())
{
    if (empty($modname)) {
        return false;
    }

    global $HTTP_SERVER_VARS;

    // Hostname
    $host = $HTTP_SERVER_VARS['HTTP_HOST'];
    if (empty($host)) {
        $host = getenv('HTTP_HOST');
        if (empty($host)) {
            return false;
        }
    }

    // The arguments
    $urlargs[] = "module=$modname";
    if ((!empty($type)) && ($type != 'user')) {
        $urlargs[] = "type=$type";
    }
    if ((!empty($func)) && ($func != 'main')) {
        $urlargs[] = "func=$func";
    }
    $urlargs = join('&', $urlargs);
    $url = "index.php?$urlargs";

    foreach ($args as $k=>$v) {
        if (is_array($v)) {
            foreach($v as $l=>$w) {
                $url .= "&$k" . "[$l]=$w";
            }
        } else {
            $url .= "&$k=$v";
        }
    }


    // The URL
    return pnGetBaseURL() . $url;
}

/**
 * see if a module is available
 * @returns bool
 * @return true if the module is available, false if not
 */
function pnModAvailable($modname)
{
    if (empty($modname)) {
        return false;
    }

    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();

    $modulestable = $pntable['modules'];
    $modulescolumn = &$pntable['modules_column'];
    $query = "SELECT $modulescolumn[state]
              FROM $modulestable
              WHERE $modulescolumn[name] = '" . pnVarPrepForStore($modname) . "'";
    $result = $dbconn->Execute($query);

    if($dbconn->ErrorNo() != 0) {
        return;
    }

    if ($result->EOF) {
        return false;
    }

    list($state) = $result->fields;
    $result->Close();

    if ($state == _PNMODULE_STATE_ACTIVE) {
        return true;
    } else {
        return false;
    }
}

/**
 * get name of current top-level module
 * @returns string
 * @return the name of the current top-level module, false if not in a module
 */
function pnModGetName() {
    $modname = pnVarCleanFromInput('module');
    if (empty($modname)) {
        $name = pnVarCleanFromInput('name');
        if (empty($name)) {
            global $ModName;
            if (empty($ModName)) {
                return false;
            }
            $modname = preg_replace('/^NS-/', '', $ModName);
            return $modname;
        }
        return $name;
    } else {
        $modname = preg_replace('/^NS-/', '', $modname);
        return $modname;
    }
}

/**
 * register a hook function
 * @param hookobject the hook object
 * @param hookaction the hook action
 * @param hookarea the area of the hook (either 'GUI' or 'API')
 * @param hookmodule name of the hook module
 * @param hooktype name of the hook type
 * @param hookfunc name of the hook function
 */
function pnModRegisterHook($hookobject,
                           $hookaction,
                           $hookarea,
                           $hookmodule,
                           $hooktype,
                           $hookfunc)
{
    
    // Get database info
    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();
    $hookstable = $pntable['hooks'];
    $hookscolumn = &$pntable['hooks_column'];

    // Insert hook
    $sql = "INSERT INTO $hookstable (
              $hookscolumn[id],
              $hookscolumn[object],
              $hookscolumn[action],
              $hookscolumn[tarea],
              $hookscolumn[tmodule],
              $hookscolumn[ttype],
              $hookscolumn[tfunc])
            VALUES (
              " . pnVarPrepForStore($dbconn->GenId($hookstable)) . ",
              '" . pnVarPrepForStore($hookobject) . "',
              '" . pnVarPrepForStore($hookaction) . "',
              '" . pnVarPrepForStore($hookarea) . "',
              '" . pnVarPrepForStore($hookmodule) . "',
              '" . pnVarPrepForStore($hooktype) . "',
              '" . pnVarPrepForStore($hookfunc) . "')";
    $dbconn->Execute($sql);

    if($dbconn->ErrorNo() != 0) {
        return false;
    }

    return true;
}

/**
 * unregister a hook function
 * @param hookobject the hook object
 * @param hookaction the hook action
 * @param hookarea the area of the hook (either 'GUI' or 'API')
 * @param hookmodule name of the hook module
 * @param hooktype name of the hook type
 * @param hookfunc name of the hook function
 */
function pnModUnregisterHook($hookobject,
                             $hookaction,
                             $hookarea,
                             $hookmodule,
                             $hooktype,
                             $hookfunc)
{
    
    // Get database info
    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();
    $hookstable = $pntable['hooks'];
    $hookscolumn = &$pntable['hooks_column'];

    // Remove hook
    $sql = "DELETE FROM $hookstable
            WHERE $hookscolumn[object] = '" . pnVarPrepForStore($hookobject) . "'
             AND $hookscolumn[action] = '" . pnVarPrepForStore($hookaction) . "'
             AND $hookscolumn[tarea] = '" . pnVarPrepForStore($hookarea) . "'
             AND $hookscolumn[tmodule] = '" . pnVarPrepForStore($hookmodule) . "'
             AND $hookscolumn[ttype] = '" . pnVarPrepForStore($hooktype) . "'
             AND $hookscolumn[tfunc] = '" . pnVarPrepForStore($hookfunc) . "'";
    $dbconn->Execute($sql);

    if($dbconn->ErrorNo() != 0) {
        return false;
    }

    return true;
}

/**
 * carry out hook operations for module
 * @param hookobject the object the hook is called for - either 'item' or 'category'
 * @param hookaction the action the hook is called for - one of 'create', 'delete', 'transform', or 'display'
 * @param hookid the id of the object the hook is called for (module-specific)
 * @param extrainfo extra information for the hook, dependent on hookaction
 * @returns string
 * @return output from hooks
 */
function pnModCallHooks($hookobject, $hookaction, $hookid, $extrainfo) {

    // Get database info
    list($dbconn) = pnDBGetConn();
    $pntable = pnDBGetTables();
    $hookstable = $pntable['hooks'];
    $hookscolumn = &$pntable['hooks_column'];

    // Get applicable hooks
    $sql = "SELECT $hookscolumn[tarea],
                   $hookscolumn[tmodule],
                   $hookscolumn[ttype],
                   $hookscolumn[tfunc]
            FROM $hookstable
            WHERE $hookscolumn[smodule] = '" . pnVarPrepForStore(pnModGetName()) . "'
            AND $hookscolumn[object] = '" . pnVarPrepForStore($hookobject) . "'
            AND $hookscolumn[action] = '" . pnVarPrepForStore($hookaction) . "'";
    $result = $dbconn->Execute($sql);
                  
    if($dbconn->ErrorNo() != 0) {
        return null;
    }

    $output = '';

    // Call each hook
    for (; !$result->EOF; $result->MoveNext()) {
        list($hookarea, $hookmodule, $hooktype, $hookfunc) = $result->fields;
        if ($hookarea == 'GUI') {
            if (pnModAvailable($hookmodule, $hooktype) &&
                pnModLoad($hookmodule, $hooktype)) {
                $output .= pnModFunc($hookmodule,
                                     $hooktype,
                                     $hookfunc,
                                     array('objectid' => $hookid,
                                           'extrainfo' => $extrainfo));
            }
        } else {
            if (pnModAvailable($hookmodule, $hooktype) &&
                pnModAPILoad($hookmodule, $hooktype)) {
                $extrainfo = pnModAPIFunc($hookmodule,
                                          $hooktype,
                                          $hookfunc,
                                          array('objectid' => $hookid,
                                                'extrainfo' => $extrainfo));
            }
        }
    }

    if ($hookaction == 'display') {
        return $output;
    } else {
        return $extrainfo;
    }
}

?>