<?php

/**
 * File from http://PrestaShow.pl
 *
 * DISCLAIMER
 * Do not edit or add to this file if you wish to upgrade this module to newer
 * versions in the future.
 *
 *  @authors     PrestaShow.pl <kontakt@prestashow.pl>
 *  @copyright   2015 PrestaShow.pl
 *  @license     http://PrestaShow.pl/license
 */
class PShow_Combination_Generator
{

    private static $instance = null;

    public static function getInstance()
    {
        if (self::$instance === null) {
            self::$instance = new PShow_Combination_Generator();
        }

        return self::$instance;
    }

    /**
     * Create product combinations
     * 
     * @param array $list
     * @return array
     */
    protected function createCombinations($list)
    {
        if (count($list) <= 1) {
            return count($list) ? array_map(create_function('$v', 'return (array($v));'), reset($list)) : $list;
        }
        $res = array();
        $first = array_pop($list);
        foreach ($first as $attribute) {
            $tab = $this->createCombinations($list);
            foreach ($tab as $to_add) {
                $res[] = is_array($to_add) ? array_merge($to_add, array($attribute)) : array($to_add, $attribute);
            }
        }
        return $res;
    }

    /**
     * Set product combinations impact
     * 
     * @param integer $id_product
     * @param array $tab
     * @return boolean
     */
    protected function setAttributesImpacts($id_product, $tab)
    {
        $attributes = array();
        foreach ($tab as $group) {
            foreach ($group as $attribute) {
                $price = preg_replace('/[^0-9.]/', '', str_replace(',', '.', 0)); //Tools::getValue('price_impact_' . (int) $attribute)));
                $weight = preg_replace('/[^0-9.]/', '', str_replace(',', '.', 0)); //Tools::getValue('weight_impact_' . (int) $attribute)));
                $attributes[] = '(' . (int) $id_product . ', ' . (int) $attribute . ', ' . (float) $price . ', ' . (float) $weight . ')';
            }
        }

        return Db::getInstance()->execute('
		INSERT INTO `' . _DB_PREFIX_ . 'attribute_impact` (`id_product`, `id_attribute`, `price`, `weight`)
		VALUES ' . implode(',', $attributes) . '
		ON DUPLICATE KEY UPDATE `price` = VALUES(price), `weight` = VALUES(weight)');
    }

    public function generateMultipleCombinations($combinations, $attributes, $product)
    {
        $res = true;
        $default_on = 1;
        foreach ($combinations as $key => $combination) {
            $id_combination = (int) $product->productAttributeExists($attributes[$key], false, null, true, true);
            $obj = new Combination($id_combination, null, PShow_Import::getInstance()->id_shop);

            if ($id_combination) {
                $obj->minimal_quantity = 1;
                $obj->available_date = '0000-00-00';
            }

            foreach ($combination as $field => $value) {
                if ($field == 'images') {
                    continue;
                }
                $obj->$field = $value;
            }

            $obj->default_on = $default_on;
            $default_on = 0;
            $product->setAvailableDate();

            try {
                $obj->save();
            } catch (PrestaShopDatabaseException $e) {
                $obj->default_on = false;
                $obj->save();
            }

            $obj->setImages($combination['images']);

            if (!$id_combination) {
                $attribute_list = array();
                foreach ($attributes[$key] as $id_attribute) {
                    $attribute_list[] = array(
                        'id_product_attribute' => (int) $obj->id,
                        'id_attribute' => (int) $id_attribute
                    );
                }
                $res &= Db::getInstance()->insert('product_attribute_combination', $attribute_list);
            }
        }

        return $res;
    }

    public function setFirstCombinationAsDefault($id_product)
    {
        $id_product = (int) $id_product;
        $q = 'UPDATE IGNORE  `ps_product_attribute_shop` SET `default_on` = NULL WHERE `id_product` = ' . $id_product . ';
            UPDATE IGNORE  `ps_product_attribute` SET `default_on` = NULL WHERE `id_product` = ' . $id_product . ';

            UPDATE IGNORE  `ps_product_attribute_shop` 
            SET `default_on` = 1
            WHERE `id_product` = ' . $id_product . ' 
                AND `id_product_attribute` IN (
                    SELECT pa.`id_product_attribute` 
                    FROM `ps_product_attribute` pa
                    JOIN `ps_product_attribute_combination` pac
                        ON (pac.`id_product_attribute` = pa.`id_product_attribute`)
                    ORDER BY pa.`id_product_attribute` ASC
                );

            UPDATE IGNORE  `ps_product_attribute`
            SET `default_on` = 1
            WHERE `id_product` = ' . $id_product . ' 
                AND `id_product_attribute` IN (
                    SELECT `id_product_attribute`
                    FROM `ps_product_attribute_shop` 
                    WHERE  `default_on` = 1
                );';
        Db::getInstance()->query($q);
    }

    /**
     * Generate all possible combinations for product
     * 
     * @param integer $id_product
     */
    public function generateCombinationsForProduct($id_product)
    {

        if (PShow_Import::getInstance() && Module::getInstanceByName("pagecache")) {
            PShow_Log::addImportLog(
                "Disabling module: pagecache..." . (Module::disableByName("pagecache") ? 'success' : 'failed')
            );
        }

        if (PShow_Import::getInstance()) {
            PShow_Log::addImportLog(
                "Generating all possible combinations for product id: " . $id_product
            );
        }

        if (PShow_Import::getInstance()) {
            PShow_Log::addImportLog(
                "Getting all attributes from product..."
            );
        }

        // get all product attributes
        $q = "SELECT DISTINCT pac.`id_attribute`, a.`id_attribute_group` "
            . "FROM `" . _DB_PREFIX_ . "product_attribute_combination` pac "
            . "JOIN `" . _DB_PREFIX_ . "product_attribute` pa ON (pa.`id_product_attribute` = pac.`id_product_attribute`) "
            . "JOIN `" . _DB_PREFIX_ . "attribute` a ON (a.`id_attribute` = pac.`id_attribute`) "
            . "WHERE pa.`id_product` = " . (int) $id_product;
        $attributes = Db::getInstance()->executeS($q);

        // product don't have any combinations
        if (!count($attributes)) {
            if (PShow_Import::getInstance()) {
                PShow_Log::addImportLog(
                    "Product don't have any attributes assigned... "
                );
            }
            return;
        }

        if (PShow_Import::getInstance()) {
            PShow_Log::addImportLog(
                "Preparing attributes array..."
            );
        }

        $tab = array();
        foreach ($attributes as $k => $attribute) {
            if (!isset($tab[$attribute['id_attribute_group']])) {
                $tab[$attribute['id_attribute_group']] = array();
            }
            array_push($tab[$attribute['id_attribute_group']], $attribute['id_attribute']);
        }

        // product have only one group of attributes - module won't generate any new
        if (count($tab) <= 1) {
            if (PShow_Import::getInstance()) {
                PShow_Log::addImportLog(
                    "Generating have only one group of attributes, skipping..."
                );
            }
            $this->setFirstCombinationAsDefault($id_product);
            return;
        }

        $product = new Product((int) $id_product, false, null, PShow_Import::getInstance()->id_shop);

        if (PShow_Import::getInstance()) {
            PShow_Log::addImportLog(
                "Getting attributes impact..."
            );
        }

        $this->setAttributesImpacts($id_product, $tab);

        if (PShow_Import::getInstance()) {
            PShow_Log::addImportLog(
                "Preparing combinations..."
            );
        }

        $combinations = array_values($this->createCombinations($tab));

        $imagesToRemove = array();
        $values = array();
        foreach ($combinations as $attributes) {

            if (PShow_Import::getInstance()) {
                PShow_Log::addImportLog(
                    "Preparing combination values for attributes: " . implode(',', $attributes)
                );
            }

            $images = array();

            $q = "SELECT pai.`id_image`, pai.`id_product_attribute`
                FROM `" . _DB_PREFIX_ . "product_attribute_image` pai
                JOIN `" . _DB_PREFIX_ . "product_attribute` pa ON (pa.`id_product` = " . $id_product . " AND pa.`id_product_attribute` = pai.`id_product_attribute`)
                WHERE pai.`id_product_attribute` IN (
                  SELECT pac.`id_product_attribute`
                  FROM `" . _DB_PREFIX_ . "product_attribute_combination` pac
                  WHERE (pac.`id_attribute` = " . implode(' OR pac.`id_attribute` = ', $attributes) . ") AND pac.`id_product_attribute` > 0
                )";
            $rows = Db::getInstance(_PS_USE_SQL_SLAVE_)->executeS($q);
            if (count($rows)) {
                foreach ($rows as $row) {
                    $imagesToRemove[] = $row;
                    if (in_array((int) $row['id_image'], $images))
                        continue;
                    array_push($images, (int) $row['id_image']);
                }
                unset($rows);
            }

            $reference = uniqid($product->id . '-' . $product->reference . '-', false);

            $values[] = array(
                'id_product' => (int) $product->id,
                'price' => (float) 0,
                'weight' => (float) 0,
                'ecotax' => 0,
                'images' => $images,
                'quantity' => (int) 0,
                'reference' => $reference,
                'default_on' => 0,
                'available_date' => '0000-00-00'
            );
        }

        if (PShow_Import::getInstance() && Module::getInstanceByName("pagecache")) {
            PShow_Log::addImportLog(
                "Enabling module: pagecache..." . (Module::enableByName("pagecache") ? 'success' : 'failed')
            );
        }

        if (PShow_Import::getInstance()) {
            PShow_Log::addImportLog(
                "Removing current product combinations..."
            );
        }

        // remove all existing product combinations
        $product->deleteProductAttributes();
        $q = "DELETE FROM `" . _DB_PREFIX_ . "product_attribute_image` "
            . "WHERE `id_product_attribute` = 0; ";
        $q .= "DELETE FROM `" . _DB_PREFIX_ . "product_attribute_image` "
            . "WHERE `id_image` NOT IN (SELECT `id_image` FROM `" . _DB_PREFIX_ . "image`); ";
        $q .= "DELETE FROM `" . _DB_PREFIX_ . "product_attribute_image` "
            . "WHERE `id_product_attribute` NOT IN ("
            . "SELECT `id_product_attribute` FROM `" . _DB_PREFIX_ . "product_attribute` WHERE `id_product` > 0"
            . "); ";
        foreach ($imagesToRemove as $img) {
            $q .= "DELETE IGNORE FROM `" . _DB_PREFIX_ . "product_attribute_image` "
                . "WHERE `id_product_attribute` = " . $img['id_product_attribute'] . " "
                . "AND `id_image` = " . $img['id_image'] . "; ";
        }
        Db::getInstance()->query($q);

        if (PShow_Import::getInstance()) {
            PShow_Log::addImportLog(
                "Generating new combinations..."
            );
        }

        // generate combinations
        $this->generateMultipleCombinations($values, $combinations, $product);

        if (PShow_Import::getInstance()) {
            PShow_Log::addImportLog(
                "Setting first combination as default..."
            );
        }

        $this->setFirstCombinationAsDefault($id_product);
    }
}