SUPEE-6788: fixing blocks used in the database

<?php
/**
 * SwiftOtter_Base is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * SwiftOtter_Base 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.
 * You should have received a copy of the GNU General Public License
 * along with SwiftOtter_Base. If not, see <http://www.gnu.org/licenses/>.
 *
 * Copyright: 2015 (c) SwiftOtter Studios
 *
 * @author Jesse Maxwell
 * @copyright Swift Otter Studios, 2/20/15
 * @package default
 **/

/** @var $installer Mage_Eav_Model_Entity_Setup */
$installer = $this;
$installer->startSetup();

/**
 * Loads the blocks associated with CMS pages
 * @param Mage_Eav_Model_Entity_Setup $installer
 * @return array
 */
function getCmsBlocks (Mage_Eav_Model_Entity_Setup $installer) {
    $outputBlocks = array();

    $cmsPages = $installer->getConnection()->select();
    if (Mage::helper('core')->isModuleEnabled('Clever_Cms')) {
        $table = $installer->getTable('cms/page') . '_tree';
    } else {
        $table = $installer->getTable('cms/page');
    }

    $cmsPages->from($table, array('content'));
    $cmsPages->where('content LIKE ?', '%{{block%');

    foreach($installer->getConnection()->fetchCol($cmsPages) as $pageId => $content) {
        $outputBlocks = array_merge_recursive(parseForBlocks($content), $outputBlocks);
    }

    return $outputBlocks;
}

/**
 * Loads the blocks associated with products
 *
 * @param Mage_Eav_Model_Entity_Setup $installer
 * @return array
 */
function getProductBlocks (Mage_Eav_Model_Entity_Setup $installer) {
    $outputBlocks = array();

    $productEntityType = Mage::getModel('eav/entity_type')->loadByCode(Mage_Catalog_Model_Product::ENTITY);

    $productAttributes = Mage::getResourceModel('eav/entity_attribute_collection');
    $productAttributes->addFieldToFilter('frontend_input', array('eq' => 'textarea'))
        ->addFieldToFilter('entity_type_id', array('eq' => $productEntityType->getId()));

    foreach ($productAttributes as $attribute) {
        $usedAttributes = $installer->getConnection()->select();
        $usedAttributes->from($installer->getTable($attribute->getBackendTable()), array('value'))
            ->where('attribute_id = ?', $attribute->getAttributeId())
            ->where('value LIKE ?', "%{{block%");

        foreach ($installer->getConnection()->fetchCol($usedAttributes) as $attributeContent) {
            $outputBlocks = array_merge_recursive(parseForBlocks($attributeContent), $outputBlocks);
        }
    }

    return $outputBlocks;
}

/**
 * Loads the blocks already in the database
 *
 * @param Mage_Eav_Model_Entity_Setup $installer
 * @return array
 */
function getBlocksAlreadyInDb (Mage_Eav_Model_Entity_Setup $installer) {
    $select = $installer->getConnection()->select();
    $select->from($installer->getTable('admin/permission_block'), 'block_name');

    return $installer->getConnection()->fetchCol($select);
};

/**
 * Finds the block types in the content provided
 *
 * @param $content
 * @return array
 */
function parseForBlocks ($content){
    $output = array();

    preg_match_all("/{{(block|widget).*type=\"(.+)\".*}}/imU", $content, $output);

    if (count($output) >= 3) {
        return $output[2];
    } else {
        return array();
    }
};

/**
 * Final phase of action: adding the block types to the database
 *
 * @param Mage_Eav_Model_Entity_Setup $installer
 * @param $blocks
 */
function addToAllowableBlocks (Mage_Eav_Model_Entity_Setup $installer, $blocks){
    try {
        $installer->getConnection()->beginTransaction();

        $block = Mage::getModel('admin/block');
        foreach ($blocks as $blockName) {
            $installer->getConnection()->insert($installer->getTable('admin/permission_block'),
                array(
                    'block_name' => $blockName,
                    'is_allowed' => 1
                )
            );
        }

        $installer->getConnection()->commit();
    } catch (Exception $ex) {
        $installer->getConnection()->rollBack();
    }
};

/**
 * This is where the functionality happens:
 *  1) finding the blocks used by CMS pages and products
 *      *: loads all products' attributes that have the textarea type
 *  2) merges them and ensures only unique values are there
 *  3) adds these to the database.
 */

$usedBlocks = array_merge(
    getProductBlocks($installer),
    getCmsBlocks($installer)
);
$usedBlocks = array_unique($usedBlocks);

$existingBlocks = getBlocksAlreadyInDb($installer);
addToAllowableBlocks($installer, array_diff($usedBlocks, $existingBlocks));

$installer->endSetup();