<?php

class App_Faq_Search_Obj extends App_Faq_Obj
{
    const TYPE_CATEGORY = 'category';
    const TYPE_QUESTION = 'question';

    /** @var array */
    protected $_filterFields = ['question', 'rawAnswer'];

    /** @var array */
    protected $_categoryFilterFields = ['title'];

    /** @var string */
    protected $_sitemapUrl;

    /** @var string */
    protected $_tableAliasCategory = 'FaqCategory';

    /**
     * @return Zend_Db_Select
     */
    public function getListSelect()
    {
        if (null === $this->_select) {
            $this->_select = $this->_db->select();
            $this->_select->union([
                $this->_getCategoryList4Select(),
                $this->_getQuestionList4Select(),
            ]);

            $this->_applySelectOptions($this->_select, $this->_selectOptions);
        }

        return $this->_select;
    }

    /**
     * @param Zend_Db_Select $select
     * @param string $tableAlias
     * @param array $filterFields
     * @return App_Faq_Search_Obj
     */
    protected function _unionFilter(Zend_Db_Select $select, $tableAlias, array $filterFields)
    {
        if (!$this->hasFilter()) {
            return $this;
        }

        if (!empty($filterFields) && array_key_exists('query', $this->_filter)) {
            Qs_Db_Filter::where($select, [$tableAlias => $filterFields], $this->_filter['query']);
        }

        $filter = $this->_getCleanedFilter($this->_filter);
        Qs_Db::filter($select, $filter, $this->_tableShortAlias ?: $this->_tableAlias);

        return $this;
    }

    /**
     * @return Zend_Db_Select
     */
    protected function _getCategoryList4Select()
    {
        $select = $this->_db->select();

        $columns = [
            'type'       => new Zend_Db_Expr('"' . static::TYPE_CATEGORY . '"'),
            'categoryId' => 'id',
            'id',
            'title',
            'alias',
            'content'    => new Zend_Db_Expr('""'),
        ];
        $select->from($this->_getPair($this->_tableAliasCategory), $columns);

        $select->where('`' . $this->_tableAliasCategory . '`.`enabled` = "y"');
        $select->where('EXISTS (' . $this->_getHasQuestionsSelect() . ')');

        $this->_unionFilter($select, $this->_tableAliasCategory, $this->_categoryFilterFields);

        return $select;
    }

    /**
     * @return Zend_Db_Select;
     */
    protected function _getHasQuestionsSelect()
    {
        $select = $this->_db->select();
        $select->from($this->_getPair($this->_tableAlias), new Zend_Db_Expr('1'));
        $select->where('`' . $this->_tableAlias . '`.`categoryId` = `' . $this->_tableAliasCategory . '`.`id`');
        $select->where('`' . $this->_tableAlias . '`.`enabled` = "y"');
        $select->limit(1);
        return $select;
    }

    /**
     * @return Zend_Db_Select
     */
    protected function _getQuestionList4Select()
    {
        $select = $this->_db->select();

        $columns = [
            'type'    => new Zend_Db_Expr('"' . static::TYPE_QUESTION . '"'),
            'categoryId',
            'id',
            'title'   => 'question',
            'alias'   => "CONCAT({$this->_tableAliasCategory}.`alias`, '#n-', {$this->_tableAlias}.id)",
            'content' => 'answer',
        ];
        $select->from($this->_getPair($this->_tableAlias), $columns);

        $select->join(
            $this->_getPair($this->_tableAliasCategory),
            '`' . $this->_tableAlias . '`.`categoryId` = `' . $this->_tableAliasCategory . '`.`id`',
            []
        );

        $select->where('`' . $this->_tableAlias . '`.`enabled` = "y"');
        $select->where('`' . $this->_tableAliasCategory . '`.`enabled` = "y"');

        $this->_unionFilter($select, $this->_tableAlias, $this->_filterFields);

        return $select;
    }

    /**
     * @return bool|string
     * @throws Qs_Exception
     */
    protected function _getSitemapUlr()
    {
        if (null === $this->_sitemapUrl) {
            $this->_sitemapUrl = Qs_SiteMap::findFirst(null, ['type' => 'Faq_'], null, 'url');
            if (!$this->_sitemapUrl) {
                throw new Qs_Exception('Can not determine FAQ URL');
            }
        }
        return $this->_sitemapUrl;
    }

    /**
     * @param array $list items list
     * @param array $providerOptions provider options from site/App/Search/config.php
     * @return App_Faq_Search_Obj
     */
    protected function _prepareSearchList(array &$list, array $providerOptions)
    {
        $this->_prepareList($list);

        if (!empty($list)) {
            foreach ($list as &$row) {
                $row['title'] = Qs_Text_Mark::markSearchWords($row['title'], $this->getFilter('query'));
                $row['searchUrl'] = $this->_getSitemapUlr() . '/' . $row['alias'];
                if (static::TYPE_QUESTION == $row['type']) {
                    $row['content'] = Qs_Text_Mark::prepareSearchText($row, ['content']);
                    $row['content'] = Qs_Text_Mark::markSearchWords($row['content'], $this->getFilter('query'));
                }
            }
        }

        return $this;
    }
}