<?php
/*
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.phpdoctrine.org>.
 */

/**
 * VariableDeclaration = identifier [["AS"] IdentificationVariable]
 *
 * @package     Doctrine
 * @subpackage  Query
 * @author      Guilherme Blanco <guilhermeblanco@hotmail.com>
 * @author      Janne Vanhala <jpvanhal@cc.hut.fi>
 * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
 * @link        http://www.phpdoctrine.org
 * @since       2.0
 * @version     $Revision$
 */
class Doctrine_Query_Production_VariableDeclaration extends Doctrine_Query_Production
{
    protected $_componentName;

    protected $_componentAlias;


    public function syntax($paramHolder)
    {
        // VariableDeclaration = identifier [["AS"] IdentificationVariable]
        if ($this->_parser->match(Doctrine_Query_Token::T_IDENTIFIER)) {
            // identifier
            $this->_componentName = $this->_parser->token['value'];
        }

        if ($this->_isNextToken(Doctrine_Query_Token::T_AS)) {
            $this->_parser->match(Doctrine_Query_Token::T_AS);
        }

        if ($this->_isNextToken(Doctrine_Query_Token::T_IDENTIFIER)) {
            $paramHolder->set('componentName', $this->_componentName);

            // Will return an identifier, with the semantical check already applied
            $this->_componentAlias = $this->AST('IdentificationVariable', $paramHolder);

            $paramHolder->remove('componentName');
        }
    }


    public function semantical($paramHolder)
    {
        $parserResult = $this->_parser->getParserResult();

        if ($parserResult->hasQueryComponent($this->_componentName)) {
            // As long as name != alias, try to bring the queryComponent from name (already processed)
            $queryComponent = $parserResult->getQueryComponent($this->_componentName);

            // Check if we defined _componentAlias. We throw semantical error if not
            if ($this->_componentAlias === null) {
                $componentName = $queryComponent['metadata']->getClassName();

                $this->_parser->semanticalError(
                    "Cannot re-declare component '{$this->_componentName}'. Please assign an alias to it."
                );

                return;
            }
        } else {
            // No queryComponent was found. We will have to build it for the first time

            // Get the connection for the component
            $conn = $this->_em->getConnection();

            // Retrieving ClassMetadata and Mapper
            try {
                $classMetadata = $this->_em->getMetadata($this->_componentName);

                // Building queryComponent
                $queryComponent = array(
                    'metadata' => $classMetadata,
                    'parent'   => null,
                    'relation' => null,
                    'map'      => null,
                    'scalar'   => null,
                );
            } catch (Doctrine_Exception $e) {
                $this->_parser->semanticalError($e->getMessage());

                return;
            }
        }

        // Define ParserResult assertions for later usage
        $tableAlias = $this->_parser->getParserResult()->generateTableAlias($this->_componentName);

        if ($this->_componentAlias === null) {
            $this->_componentAlias = $this->_componentName;
        }

        $parserResult->setQueryComponent($this->_componentAlias, $queryComponent);
        $parserResult->setTableAlias($tableAlias, $this->_componentAlias);
    }


    public function buildSql()
    {
        // Basic handy variables
        $parserResult = $this->_parser->getParserResult();
        $queryComponent = $parserResult->getQueryComponent($this->_componentAlias);

        // Retrieving connection
        $conn = $this->_em->getConnection();

        return $conn->quoteIdentifier($queryComponent['metadata']->getTableName()) . ' '
             . $conn->quoteIdentifier($parserResult->getTableAliasFromComponentAlias($this->_componentAlias));
    }
    
    /**
     * Visitor support.
     */
    public function accept($visitor)
    {
        $visitor->visitVariableDeclaration($this);
    }
    
    /* Getters */
    
    public function getComponentName()
    {
        return $this->_componentName;
    }
    
    public function getComponentAlias()
    {
        return $this->_componentAlias;
    }
}