<?php
/**
 * IndexProcessor.php
 *
 * This file implements the processor for the INDEX statements.
 *
 * PHP version 5
 *
 * LICENSE:
 * Copyright (c) 2010-2014 Justin Swanhart and André Rothe
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 *
 * @author    André Rothe <andre.rothe@phosco.info>
 * @copyright 2010-2014 Justin Swanhart and André Rothe
 * @license   http://www.debian.org/misc/bsd.license  BSD License (3 Clause)
 * @version   SVN: $Id$
 *
 */

require_once dirname(__FILE__) . '/AbstractProcessor.php';
require_once dirname(__FILE__) . '/IndexColumnListProcessor.php';
require_once dirname(__FILE__) . '/../utils/ExpressionType.php';

/**
 * This class processes the INDEX statements.
 *
 * @author  André Rothe <andre.rothe@phosco.info>
 * @license http://www.debian.org/misc/bsd.license  BSD License (3 Clause)
 *  
 */
class IndexProcessor extends AbstractProcessor {

    protected function getReservedType($token) {
        return array('expr_type' => ExpressionType::RESERVED, 'base_expr' => $token);
    }

    protected function getConstantType($token) {
        return array('expr_type' => ExpressionType::CONSTANT, 'base_expr' => $token);
    }

    protected function getOperatorType($token) {
        return array('expr_type' => ExpressionType::OPERATOR, 'base_expr' => $token);
    }

    protected function processIndexColumnList($parsed) {
        $processor = new IndexColumnListProcessor();
        return $processor->process($parsed);
    }

    public function process($tokens) {

        $currCategory = 'INDEX_NAME';
        $result = array('base_expr' => false, 'name' => false, 'no_quotes' => false, 'index-type' => false, 'on' => false,
                        'options' => false);
        $expr = array();
        $base_expr = '';
        $skip = 0;

        foreach ($tokens as $tokenKey => $token) {
            $trim = trim($token);
            $base_expr .= $token;

            if ($skip > 0) {
                $skip--;
                continue;
            }

            if ($skip < 0) {
                break;
            }

            if ($trim === '') {
                continue;
            }

            $upper = strtoupper($trim);
            switch ($upper) {

            case 'USING':
                if ($prevCategory === 'CREATE_DEF') {
                    $expr[] = $this->getReservedType($trim);
                    $currCategory = 'TYPE_OPTION';
                    continue 2;
                }
                if ($prevCategory === 'TYPE_DEF') {
                    $expr[] = $this->getReservedType($trim);
                    $currCategory = 'INDEX_TYPE';
                    continue 2;
                }
                // else ?
                break;

            case 'KEY_BLOCK_SIZE':
                if ($prevCategory === 'CREATE_DEF') {
                    $expr[] = $this->getReservedType($trim);
                    $currCategory = 'INDEX_OPTION';
                    continue 2;
                }
                // else ?
                break;

            case 'WITH':
                if ($prevCategory === 'CREATE_DEF') {
                    $expr[] = $this->getReservedType($trim);
                    $currCategory = 'INDEX_PARSER';
                    continue 2;
                }
                // else ?
                break;

            case 'PARSER':
                if ($currCategory === 'INDEX_PARSER') {
                    $expr[] = $this->getReservedType($trim);
                    continue 2;
                }
                // else ?
                break;

            case 'COMMENT':
                if ($prevCategory === 'CREATE_DEF') {
                    $expr[] = $this->getReservedType($trim);
                    $currCategory = 'INDEX_COMMENT';
                    continue 2;
                }
                // else ?
                break;

            case 'ALGORITHM':
            case 'LOCK':
                if ($prevCategory === 'CREATE_DEF') {
                    $expr[] = $this->getReservedType($trim);
                    $currCategory = $upper . '_OPTION';
                    continue 2;
                }
                // else ?
                break;

            case '=':
            // the optional operator
                if (substr($currCategory, -7, 7) === '_OPTION') {
                    $expr[] = $this->getOperatorType($trim);
                    continue 2; // don't change the category
                }
                // else ?
                break;

            case 'ON':
                if ($prevCategory === 'CREATE_DEF' || $prevCategory === 'TYPE_DEF') {
                    $expr[] = $this->getReservedType($trim);
                    $currCategory = 'TABLE_DEF';
                    continue 2;
                }
                // else ?
                break;

            default:
                switch ($currCategory) {

                case 'COLUMN_DEF':
                    if ($upper[0] === '(' && substr($upper, -1) === ')') {
                        $cols = $this->processIndexColumnList($this->removeParenthesisFromStart($trim));
                        $result['on']['base_expr'] .= $base_expr;
                        $result['on']['sub_tree'] = array('expr_type' => ExpressionType::COLUMN_LIST,
                                                          'base_expr' => $trim, 'sub_tree' => $cols);
                    }

                    $expr = array();
                    $base_expr = '';
                    $currCategory = 'CREATE_DEF';
                    break;

                case 'TABLE_DEF':
                // the table name
                    $expr[] = $this->getConstantType($trim);
                    // TODO: the base_expr should contain the column-def too
                    $result['on'] = array('expr_type' => ExpressionType::TABLE, 'base_expr' => $base_expr,
                                          'name' => $trim, 'no_quotes' => $this->revokeQuotation($trim),
                                          'sub_tree' => false);
                    $expr = array();
                    $base_expr = '';
                    $currCategory = 'COLUMN_DEF';
                    continue 3;

                case 'INDEX_NAME':
                    $result['base_expr'] = $result['name'] = $trim;
                    $result['no_quotes'] = $this->revokeQuotation($trim);

                    $expr = array();
                    $base_expr = '';
                    $currCategory = 'TYPE_DEF';
                    break;

                case 'INDEX_PARSER':
                // the parser name
                    $expr[] = $this->getConstantType($trim);
                    $result['options'][] = array('expr_type' => ExpressionType::INDEX_PARSER,
                                                 'base_expr' => trim($base_expr), 'sub_tree' => $expr);
                    $expr = array();
                    $base_expr = '';
                    $currCategory = 'CREATE_DEF';

                    break;

                case 'INDEX_COMMENT':
                // the index comment
                    $expr[] = $this->getConstantType($trim);
                    $result['options'][] = array('expr_type' => ExpressionType::COMMENT,
                                                 'base_expr' => trim($base_expr), 'sub_tree' => $expr);
                    $expr = array();
                    $base_expr = '';
                    $currCategory = 'CREATE_DEF';

                    break;

                case 'INDEX_OPTION':
                // the key_block_size
                    $expr[] = $this->getConstantType($trim);
                    $result['options'][] = array('expr_type' => ExpressionType::INDEX_SIZE,
                                                 'base_expr' => trim($base_expr), 'size' => $upper,
                                                 'sub_tree' => $expr);
                    $expr = array();
                    $base_expr = '';
                    $currCategory = 'CREATE_DEF';

                    break;

                case 'INDEX_TYPE':
                case 'TYPE_OPTION':
                // BTREE or HASH
                    $expr[] = $this->getReservedType($trim);
                    if ($currCategory === 'INDEX_TYPE') {
                        $result['index-type'] = array('expr_type' => ExpressionType::INDEX_TYPE,
                                                      'base_expr' => trim($base_expr), 'using' => $upper,
                                                      'sub_tree' => $expr);
                    } else {
                        $result['options'][] = array('expr_type' => ExpressionType::INDEX_TYPE,
                                                     'base_expr' => trim($base_expr), 'using' => $upper,
                                                     'sub_tree' => $expr);
                    }

                    $expr = array();
                    $base_expr = '';
                    $currCategory = 'CREATE_DEF';
                    break;

                case 'LOCK_OPTION':
                // DEFAULT|NONE|SHARED|EXCLUSIVE
                    $expr[] = $this->getReservedType($trim);
                    $result['options'][] = array('expr_type' => ExpressionType::INDEX_LOCK,
                                                 'base_expr' => trim($base_expr), 'lock' => $upper,
                                                 'sub_tree' => $expr);

                    $expr = array();
                    $base_expr = '';
                    $currCategory = 'CREATE_DEF';
                    break;

                case 'ALGORITHM_OPTION':
                // DEFAULT|INPLACE|COPY
                    $expr[] = $this->getReservedType($trim);
                    $result['options'][] = array('expr_type' => ExpressionType::INDEX_ALGORITHM,
                                                 'base_expr' => trim($base_expr), 'algorithm' => $upper,
                                                 'sub_tree' => $expr);

                    $expr = array();
                    $base_expr = '';
                    $currCategory = 'CREATE_DEF';

                    break;

                default:
                    break;
                }

                break;
            }

            $prevCategory = $currCategory;
            $currCategory = '';
        }

        return $result;
    }
}
?>
