<?php

/*
 * This is a simple short-hand wrapper for Doctrine_Query. It provides
 * a shorter class name and a few additional functions.
 */
class DQ extends Doctrine_Query
{
    public static $defaultClass;

    protected $preQueried;

    protected $hydratorName;

    public static function switchToMaster() {
        $dm = Doctrine_Manager::getInstance();
        $oldConn = $dm->getCurrentConnection();
        if ($dm->getConnectionName($oldConn) === 'master') {
            return $oldConn;
        }
        $dm->setCurrentConnection('master');
        $conn = $dm->getCurrentConnection();
        foreach ($oldConn->getIterator() as $table) {
            $conn->addTable($table);
            $table->setConnection($conn);
        }
        $oldConn->close();
        return $conn;
    }

    /**
     * Creates a Doctrine_Query class
     *
     * @return Doctrine_Query
     */
    public static function create($conn = null, $class = null) {
        if (self::$defaultClass) {
            $className = self::$defaultClass;
        } elseif (function_exists('get_called_class')) {
            $className = get_called_class();
        } else {
            $className = __CLASS__;
        }

        return new $className($conn, $class);
    }

    public function getDQInstance($conn = null, $class = null) {
        return self::create($conn, $class);
    }

    public function getHydratorName() {
        return $this->hydratorName;
    }

    public function setHydratorName($hydratorName) {
        $this->hydratorName = $hydratorName;
    }

    /**
     * execute
     * executes the query and populates the data set
     *
     * @param array $params
     * @return Doctrine_Collection            the root collection
     */
    public function execute($params = array(), $hydrationMode = null)
    {
        if ((is_null($hydrationMode) || $hydrationMode == Doctrine_Core::HYDRATE_RECORD) && $this->hydratorName) {
            $hydrationMode = $this->hydratorName;
        }

        return parent::execute($params, $hydrationMode);
    }

    public function preQuery()
    {
        if ($this->preQueried === true) {
            return;
        }
        $this->preQueried = true;

        // force to master if this is not a select
        if ($this->getType() !== self::SELECT) {
            $this->_conn = self::switchToMaster();
        }
    }


    /**
     * This function will wrap the current dql where statement
     * in parenthesis. This allows more complex dql statements
     * It can be called multiple times during the creation of the dql
     * where clause.
     *
     * @return $this
     */
    public function whereParenWrap() {
        $where = $this->_dqlParts['where'];
        if (count($where) > 0) {
            array_unshift($where, '(');
            array_push($where, ')');
            $this->_dqlParts['where'] = $where;
        }

        return $this;
    }

    /**
     * Create and andWhere if the where parameter is not empty
     *
     * @param string $where where string
     * @param parameters $params
     *
     * @return DQ this object
     */
    public function andWhereIf($where, $params = array()) {
        return empty($where)
            ? $this
            : $this->andWhere($where, $params);
    }

    /**
     * Create and orWhere if the where parameter is not empty
     *
     * @param string $where where string
     * @param parameters $params
     *
     * @return DQ this object
     */
    public function orWhereIf($where, $params = array()) {
        return empty($where)
            ? $this
            : $this->orWhere($where, $params);
    }

    /**
     * orderByValues
     * sets the ORDER BY using the MySQL proprietary FIELD() function to force
     * a sorting by a list of values for a single given column
     *
     * @param string $column       column name
     * @param array $values        integer values in the order in which they shold appear in the result
     * @return Doctrine_Query
     */
    public function orderByValues($column, $values)
    {
        $field = "FIELD($column";
        foreach ($values as $value) {
            $field.= ", ".(int)$value;
        }
        $field.= ")";
        return $this->orderBy($field);
    }
}