<?php
/**
 * This migration can be used to change the displayed pattern for a reference field in a module.
 * @author Oskar Stark - [email protected]
 */
class Migration0001 extends Exo_CMS_Migration
{

    /**
     *  If you want to make a line break, just fill a "<br />" to the position in the "*_PATTERN"
     */
    const NEW_PATTERN = '[*image_source*][*title*]';
    
    /* needed for "down"-migration */
    const OLD_PATTERN = '[*title*]';
    
    const TARGET_MODULE = 'gallery';
    const TARGET_ELEMENT = 'images';
    
    /* This is the module, where the TARGET_ELEMENT refers to */
    const REFERENCED_MODULE = 'image_assets';

    public function getDescription()
    {
        if ($this->getTaskDirection() === 'down')
        {
            return 'Changes old pattern ("' . self::NEW_PATTERN . '") to new pattern ("' . self::OLD_PATTERN . '") for "' . self::TARGET_ELEMENT . '" in "' . self::TARGET_MODULE . '"-Module.';
        }
        else
        {
            return 'Changes old pattern ("' . self::OLD_PATTERN . '") to new pattern ("' . self::NEW_PATTERN . '") for "' . self::TARGET_ELEMENT . '" in "' . self::TARGET_MODULE . '"-Module.';
        }
    }

    public function up()
    {
        /** @var $module Exo_CMS_Module */
        $module = self::loadModule(self::TARGET_MODULE);

        /** @var $element Exo_CMS_InputElement */
        $element = self::loadField($module, self::TARGET_ELEMENT);

        $references = $element->getExo_CMS_InputFieldReferences();

         /** @var $reference Exo_CMS_InputFieldReference */
        foreach ($references as $reference)
        {
            if ($reference->getTargetModule() === self::REFERENCED_MODULE)
            {
                $reference->setPattern(self::NEW_PATTERN);
                $reference->save();
            }
        }
    }

    public function down()
    {
        /** @var $module Exo_CMS_Module */
        $module = self::loadModule(self::TARGET_MODULE);

        /** @var $element Exo_CMS_InputElement */
        $element = self::loadField($module, self::TARGET_ELEMENT);

        $references = $element->getExo_CMS_InputFieldReferences();

        /** @var $reference Exo_CMS_InputFieldReference */
        foreach ($references as $reference)
        {
            if ($reference->getTargetModule() === self::REFERENCED_MODULE)
            {
                $reference->setPattern(self::OLD_PATTERN);
                $reference->save();
            }
        }
    }

    public function isDestructive()
    {
        return false;
    }
}