Swap Structures and Channels

MyPluginNamePlugin.php

<?php
namespace Craft;

class MyPluginNamePlugin extends BasePlugin
{
    /* --------------------------------------------------------------
    * PLUGIN INFO
    * ------------------------------------------------------------ */

    public function getName()
    {
        return Craft::t('My Plugin Name');
    }

    public function getVersion()
    {
        return '0.1';
    }

    public function getDeveloper()
    {
        return 'Somebody';
    }

    public function getDeveloperUrl()
    {
        return 'http://website.com';
    }

    /* --------------------------------------------------------------
    * HOOKS
    * ------------------------------------------------------------ */
    
    public function modifyEntrySources(&$sources, $context)
    {
        if ($context == 'index')
        {
            $sections = craft()->sections->getEditableSections();
            $editable = true;
        }
        else
        {
            $sections = craft()->sections->getAllSections();
            $editable = false;
        }

        $sectionIds = array();
        $singleSectionIds = array();
        $sectionsByType = array();

        foreach ($sections as $section)
        {
            $sectionIds[] = $section->id;

            if ($section->type == SectionType::Single)
            {
                $singleSectionIds[] = $section->id;
            }
            else
            {
                $sectionsByType[$section->type][] = $section;
            }
        }

        $sources = array(
            '*' => array(
                'label'    => Craft::t('All entries'),
                'criteria' => array('sectionId' => $sectionIds, 'editable' => $editable)
            )
        );

        if ($singleSectionIds)
        {
            $sources['singles'] = array(
                'label'    => Craft::t('Singles'),
                'criteria' => array('sectionId' => $singleSectionIds, 'editable' => $editable)
            );
        }

        $sectionTypes = array(
            SectionType::Structure => Craft::t('Structures'),
            SectionType::Channel => Craft::t('Channels'),
        );

        foreach ($sectionTypes as $type => $heading)
        {
            if (!empty($sectionsByType[$type]))
            {
                $sources[] = array('heading' => $heading);

                foreach ($sectionsByType[$type] as $section)
                {
                    $key = 'section:'.$section->id;

                    $sources[$key] = array(
                        'label'    => Craft::t($section->name),
                        'data'     => array('type' => $type, 'handle' => $section->handle),
                        'criteria' => array('sectionId' => $section->id, 'editable' => $editable)
                    );

                    if ($type == SectionType::Structure)
                    {
                        $sources[$key]['structureId'] = $section->structureId;
                        $sources[$key]['structureEditable'] = craft()->userSession->checkPermission('publishEntries:'.$section->id);
                    }
                }
            }
        }

        return $sources;
    }
}