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Direktori : /var/www/projetos/admin.iigd.com.br/vendor/phpmyadmin/sql-parser/src/Components/ |
Current File : /var/www/projetos/admin.iigd.com.br/vendor/phpmyadmin/sql-parser/src/Components/CaseExpression.php |
<?php /** * Parses a reference to a CASE expression. */ declare(strict_types=1); namespace PhpMyAdmin\SqlParser\Components; use PhpMyAdmin\SqlParser\Component; use PhpMyAdmin\SqlParser\Context; use PhpMyAdmin\SqlParser\Parser; use PhpMyAdmin\SqlParser\Token; use PhpMyAdmin\SqlParser\TokensList; use function count; /** * Parses a reference to a CASE expression. * * @final */ class CaseExpression extends Component { /** * The value to be compared. * * @var Expression */ public $value; /** * The conditions in WHEN clauses. * * @var array */ public $conditions = []; /** * The results matching with the WHEN clauses. * * @var array */ public $results = []; /** * The values to be compared against. * * @var array */ public $compare_values = []; /** * The result in ELSE section of expr. * * @var Expression */ public $else_result; /** * The alias of this CASE statement. * * @var string */ public $alias; /** * The sub-expression. * * @var string */ public $expr = ''; public function __construct() { } /** * @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 CaseExpression */ public static function parse(Parser $parser, TokensList $list, array $options = []) { $ret = new static(); /** * State of parser. * * @var int */ $state = 0; /** * Syntax type (type 0 or type 1). * * @var int */ $type = 0; ++$list->idx; // Skip 'CASE' for (; $list->idx < $list->count; ++$list->idx) { /** * Token parsed at this moment. * * @var Token */ $token = $list->tokens[$list->idx]; // Skipping whitespaces and comments. if (($token->type === Token::TYPE_WHITESPACE) || ($token->type === Token::TYPE_COMMENT)) { continue; } if ($state === 0) { if ($token->type === Token::TYPE_KEYWORD) { switch ($token->keyword) { case 'WHEN': ++$list->idx; // Skip 'WHEN' $newCondition = Condition::parse($parser, $list); $type = 1; $state = 1; $ret->conditions[] = $newCondition; break; case 'ELSE': ++$list->idx; // Skip 'ELSE' $ret->else_result = Expression::parse($parser, $list); $state = 0; // last clause of CASE expression break; case 'END': $state = 3; // end of CASE expression ++$list->idx; break 2; default: $parser->error('Unexpected keyword.', $token); break 2; } } else { $ret->value = Expression::parse($parser, $list); $type = 0; $state = 1; } } elseif ($state === 1) { if ($type === 0) { if ($token->type === Token::TYPE_KEYWORD) { switch ($token->keyword) { case 'WHEN': ++$list->idx; // Skip 'WHEN' $newValue = Expression::parse($parser, $list); $state = 2; $ret->compare_values[] = $newValue; break; case 'ELSE': ++$list->idx; // Skip 'ELSE' $ret->else_result = Expression::parse($parser, $list); $state = 0; // last clause of CASE expression break; case 'END': $state = 3; // end of CASE expression ++$list->idx; break 2; default: $parser->error('Unexpected keyword.', $token); break 2; } } } else { if ($token->type === Token::TYPE_KEYWORD && $token->keyword === 'THEN') { ++$list->idx; // Skip 'THEN' $newResult = Expression::parse($parser, $list); $state = 0; $ret->results[] = $newResult; } elseif ($token->type === Token::TYPE_KEYWORD) { $parser->error('Unexpected keyword.', $token); break; } } } elseif ($state === 2) { if ($type === 0) { if ($token->type === Token::TYPE_KEYWORD && $token->keyword === 'THEN') { ++$list->idx; // Skip 'THEN' $newResult = Expression::parse($parser, $list); $ret->results[] = $newResult; $state = 1; } elseif ($token->type === Token::TYPE_KEYWORD) { $parser->error('Unexpected keyword.', $token); break; } } } } if ($state !== 3) { $parser->error('Unexpected end of CASE expression', $list->tokens[$list->idx - 1]); } else { // Parse for alias of CASE expression $asFound = false; for (; $list->idx < $list->count; ++$list->idx) { $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) || ($token->type === Token::TYPE_COMMENT)) { continue; } // Handle optional AS keyword before alias if ($token->type === Token::TYPE_KEYWORD && $token->keyword === 'AS') { if ($asFound || ! empty($ret->alias)) { $parser->error('Potential duplicate alias of CASE expression.', $token); break; } $asFound = true; continue; } if ( $asFound && $token->type === Token::TYPE_KEYWORD && ($token->flags & Token::FLAG_KEYWORD_RESERVED || $token->flags & Token::FLAG_KEYWORD_FUNCTION) ) { $parser->error('An alias expected after AS but got ' . $token->value, $token); $asFound = false; break; } if ( $asFound || $token->type === Token::TYPE_STRING || ($token->type === Token::TYPE_SYMBOL && ! $token->flags & Token::FLAG_SYMBOL_VARIABLE) || $token->type === Token::TYPE_NONE ) { // An alias is expected (the keyword `AS` was previously found). if (! empty($ret->alias)) { $parser->error('An alias was previously found.', $token); break; } $ret->alias = $token->value; $asFound = false; continue; } break; } if ($asFound) { $parser->error('An alias was expected after AS.', $list->tokens[$list->idx - 1]); } $ret->expr = self::build($ret); } --$list->idx; return $ret; } /** * @param CaseExpression $component the component to be built * @param array $options parameters for building * * @return string */ public static function build($component, array $options = []) { $ret = 'CASE '; if (isset($component->value)) { // Syntax type 0 $ret .= $component->value . ' '; $valuesCount = count($component->compare_values); $resultsCount = count($component->results); for ($i = 0; $i < $valuesCount && $i < $resultsCount; ++$i) { $ret .= 'WHEN ' . $component->compare_values[$i] . ' '; $ret .= 'THEN ' . $component->results[$i] . ' '; } } else { // Syntax type 1 $valuesCount = count($component->conditions); $resultsCount = count($component->results); for ($i = 0; $i < $valuesCount && $i < $resultsCount; ++$i) { $ret .= 'WHEN ' . Condition::build($component->conditions[$i]) . ' '; $ret .= 'THEN ' . $component->results[$i] . ' '; } } if (isset($component->else_result)) { $ret .= 'ELSE ' . $component->else_result . ' '; } $ret .= 'END'; if ($component->alias) { $ret .= ' AS ' . Context::escape($component->alias); } return $ret; } }