<?php
/**
* Parses the definition of a key.
*/
namespace SqlParser\Components;
use SqlParser\Context;
use SqlParser\Component;
use SqlParser\Parser;
use SqlParser\Token;
use SqlParser\TokensList;
/**
* Parses the definition of a key.
*
* Used for parsing `CREATE TABLE` statement.
*
* @category Components
*
* @license https://www.gnu.org/licenses/gpl-2.0.txt GPL-2.0+
*/
class Key extends Component
{
/**
* All key options.
*
* @var array
*/
public static $KEY_OPTIONS = array(
'KEY_BLOCK_SIZE' => array(1, 'var'),
'USING' => array(2, 'var'),
'WITH PARSER' => array(3, 'var'),
'COMMENT' => array(4, 'var='),
);
/**
* The name of this key.
*
* @var string
*/
public $name;
/**
* Columns.
*
* @var array
*/
public $columns;
/**
* The type of this key.
*
* @var string
*/
public $type;
/**
* The options of this key.
*
* @var OptionsArray
*/
public $options;
/**
* Constructor.
*
* @param string $name the name of the key
* @param array $columns the columns covered by this key
* @param string $type the type of this key
* @param OptionsArray $options the options of this key
*/
public function __construct(
$name = null,
array $columns = array(),
$type = null,
$options = null
) {
$this->name = $name;
$this->columns = $columns;
$this->type = $type;
$this->options = $options;
}
/**
* @param Parser $parser the parser that serves as context
* @param TokensList $list the list of tokens that are being parsed
* @param array $options parameters for parsing
*
* @return Key
*/
public static function parse(Parser $parser, TokensList $list, array $options = array())
{
$ret = new self();
/**
* Last parsed column.
*
* @var array
*/
$lastColumn = array();
/**
* The state of the parser.
*
* Below are the states of the parser.
*
* 0 ----------------------[ type ]-----------------------> 1
*
* 1 ----------------------[ name ]-----------------------> 1
* 1 ---------------------[ columns ]---------------------> 2
*
* 2 ---------------------[ options ]---------------------> 3
*
* @var int
*/
$state = 0;
for (; $list->idx < $list->count; ++$list->idx) {
/**
* Token parsed at this moment.
*
* @var Token
*/
$token = $list->tokens[$list->idx];
// End of statement.
if ($token->type === Token::TYPE_DELIMITER) {
break;
}
// Skipping whitespaces and comments.
if (($token->type === Token::TYPE_WHITESPACE) || ($token->type === Token::TYPE_COMMENT)) {
continue;
}
if ($state === 0) {
$ret->type = $token->value;
$state = 1;
} elseif ($state === 1) {
if (($token->type === Token::TYPE_OPERATOR) && ($token->value === '(')) {
$state = 2;
} else {
$ret->name = $token->value;
}
} elseif ($state === 2) {
if ($token->type === Token::TYPE_OPERATOR) {
if ($token->value === '(') {
$state = 3;
} elseif (($token->value === ',') || ($token->value === ')')) {
$state = ($token->value === ',') ? 2 : 4;
if (!empty($lastColumn)) {
$ret->columns[] = $lastColumn;
$lastColumn = array();
}
}
} else {
$lastColumn['name'] = $token->value;
}
} elseif ($state === 3) {
if (($token->type === Token::TYPE_OPERATOR) && ($token->value === ')')) {
$state = 2;
} else {
$lastColumn['length'] = $token->value;
}
} elseif ($state === 4) {
$ret->options = OptionsArray::parse($parser, $list, static::$KEY_OPTIONS);
++$list->idx;
break;
}
}
--$list->idx;
return $ret;
}
/**
* @param Key $component the component to be built
* @param array $options parameters for building
*
* @return string
*/
public static function build($component, array $options = array())
{
$ret = $component->type . ' ';
if (!empty($component->name)) {
$ret .= Context::escape($component->name) . ' ';
}
$columns = array();
foreach ($component->columns as $column) {
$tmp = Context::escape($column['name']);
if (isset($column['length'])) {
$tmp .= '(' . $column['length'] . ')';
}
$columns[] = $tmp;
}
$ret .= '(' . implode(',', $columns) . ') ' . $component->options;
return trim($ret);
}
}