Created abstract structures to keep complexity and code redundancy at bay.

src/admin/abstract/controller.php

@@ -0,0 +1,189 @@
+<?php
+
+use Joomla\CMS\Factory;
+use Joomla\CMS\MVC\Controller\BaseController;
+use Joomla\CMS\Router\Route;
+
+// No direct access.
+defined('_JEXEC') or die;
+
+abstract class AbstractClubsController extends BaseController
+{
+    
+    protected abstract function getNameOfElement();
+    
+    protected function getModelName()
+    {
+        return $this->getNameOfElement();
+    }
+    
+    protected function getNameOfView()
+    {
+        return strtolower($this->getNameOfElement());
+    }
+    
+    protected abstract function getDataMapping();
+    
+    function new()
+    {
+        $obj = call_user_func(array('Clubs' . $this->getNameOfElement(), 'create' . $this->getNameOfElement()));
+        
+        // Fetch the posted data
+        $values = $this->loadData();
+
+        $this->filterPreCheck($values);
+        
+        // Check the input data
+        $error = $this->checkData($values);
+        
+        $view = $this->getNameOfView();
+        
+        if($error)
+        {
+            $urldata = $this->packData($values);
+            $this->setRedirect(Route::_("index.php?option=com_clubs&view={$view}&id=new&data={$urldata}", false));
+            return;
+        }
+        
+        $this->applyData($obj, $values);
+        
+        // Do the actual work
+        $obj->save();
+        $this->setRedirect(Route::_("index.php?option=com_clubs&view={$view}s", false));
+    }
+    
+    function change()
+    {
+        $app = Factory::getApplication();
+        $input = $app->input;
+        $id = (int) $input->post->getInt('id');
+        
+        $obj = call_user_func(array('Clubs' . $this->getNameOfElement(), 'load' . $this->getNameOfElement()), (int) $id);
+        
+        // Fetch the posted data
+        $values = $this->loadData();
+        
+        $this->filterPreCheck($values);
+        
+        // Check the input data
+        $error = $this->checkData($values);
+        
+        $view = $this->getNameOfView();
+        
+        if($error)
+        {
+            $urldata = $this->packData($values);
+            $this->setRedirect(Route::_("index.php?option=com_clubs&view={$view}&id={$id}&data={$urldata}", false));
+            return;
+        }
+        
+        $this->applyData($obj, $values);
+        
+        // Do the actual work
+        $obj->save();
+        $this->setRedirect(Route::_("index.php?option=com_clubs&view={$view}s", false));
+    }
+    
+    protected function loadData()
+    {
+        $values = array();
+        $input = Factory::getApplication()->input->post;
+        
+        foreach($this->getDataMapping() as $m => $f)
+        {
+            $filter = (isset($f['filter'])) ? $f['filter'] : 'string';
+            
+            $values[$m] = $input->get($m, null, $filter);
+        }
+        
+        return $values;
+    }
+    
+    protected function filterPreCheck(&$values){}
+    
+    protected function checkData($values)
+    {
+        $error = false;
+        // Check existence of the required fields
+        foreach ($this->getDataMapping() as $m => $v)
+        {
+            if(! isset($v['required']) || ! $v['required'])
+                continue;
+            
+            // Field is required
+            if(! $this->fieldValid($m, $values[$m], $v))
+            {
+                $fname = (isset($v['name'])) ? $v['name'] : $m;
+                Factory::getApplication()->enqueueMessage("Das Feld $fname ist obligatorisch.", 'error');
+                $error = true;
+            }
+        }
+        
+        return $error;
+    }
+    
+    protected function fieldValid($name, $value, $options)
+    {
+        if(empty($value))
+            return false;
+        
+        if(isset($options['filter']))
+        {
+            switch($options['filter'])
+            {
+                case 'string':
+                    if(empty(trim($value)))
+                        return false;
+            }
+        }
+        
+        return true;
+    }
+    
+    private function packData($values)
+    {
+        $data = array();
+        foreach($this->getDataMapping() as $i)
+            $data[$i] = $values[$i];
+            
+        return urlencode(json_encode($data));
+    }
+    
+    public function applyData($obj, $values)
+    {
+        foreach($this->getDataMapping() as $m => $v)
+        {
+            $functionName = $this->getSetterMethodName($m, $v);
+            $value = (isset($values[$m])) ? $values[$m] : null;
+            $obj->$functionName($value);
+        }
+    }
+    
+    private function getSetterMethodName($m, $options)
+    {
+        if(isset($options['setter']))
+            return $options['setter'];
+        
+        $firstChar = substr($m, 0, 1);
+        $restChars = substr($m, 1);
+        return 'set' . strtoupper($firstChar) . $restChars;
+    }
+    
+    function delete()
+    {
+        $app = Factory::getApplication();
+        
+        $id = $app->input->get->getInt('id');
+        $name = $this->getNameOfElement();
+        $app->enqueueMessage("Removal of $name with id $id.");
+        
+        $className = 'Clubs' . $this->getModelName();
+        $functionName = 'load' . $this->getModelName();
+        $element = call_user_func(array($className, $functionName), $id);
+        $element->delete();
+        
+        $view = $this->getNameOfView();
+        $this->setRedirect(Route::_("index.php?option=com_clubs&view={$view}s", false));
+    }
+    
+}