/**
* Generates Comparison Expression
*
* @param AbstractExpression $left The LHS expression.
* @param AbstractExpression $right The RHS expression.
* @param ExpressionToken $expressionToken The cmparision expression token.
* @param boolean $isCustomExpressionProvider True if the end user is responsible
* for providing the IExpressionProvider
* implementation.
*
* @return AbstractExpression
*/
private static function _generateComparisonExpression($left, $right, $expressionToken, $isCustomExpressionProvider)
{
FunctionDescription::verifyRelationalOpArguments($expressionToken, $left, $right);
//We need special handling for comparison of following types:
//1. String
//2. DateTime
//3. Guid
//4. Binary
//Will make these comparison as function calls, which will
// be converted to language specific function call by expression
// provider
$string = new OString();
if ($left->typeIs($string) && $right->typeIs($string)) {
$strcmpFunctions = FunctionDescription::stringComparisionFunctions();
$left = new FunctionCallExpression($strcmpFunctions[0], array($left, $right));
$right = new ConstantExpression(0, new Int32());
}
$dateTime = new DateTime();
if ($left->typeIs($dateTime) && $right->typeIs($dateTime)) {
$dateTimeCmpFunctions = FunctionDescription::dateTimeComparisonFunctions();
$left = new FunctionCallExpression($dateTimeCmpFunctions[0], array($left, $right));
$right = new ConstantExpression(0, new Int32());
}
$guid = new Guid();
if ($left->typeIs($guid) && $right->typeIs($guid)) {
$guidEqualityFunctions = FunctionDescription::guidEqualityFunctions();
$left = new FunctionCallExpression($guidEqualityFunctions[0], array($left, $right));
$right = new ConstantExpression(true, new Boolean());
}
$binary = new Binary();
if ($left->typeIs($binary) && $right->typeIs($binary)) {
$binaryEqualityFunctions = FunctionDescription::binaryEqualityFunctions();
$left = new FunctionCallExpression($binaryEqualityFunctions[0], array($left, $right));
$right = new ConstantExpression(true, new Boolean());
}
$null = new Null1();
if ($left->typeIs($null) || $right->typeIs($null)) {
// If the end user is responsible for implementing IExpressionProvider
// then the sub-tree for a nullability check would be:
//
// RelationalExpression(EQ/NE)
// |
// ------------
// | |
// | |
// CustomerID NULL
//
// Otherwise (In case of default PHPExpressionProvider):
//
// CustomerID eq null
// ==================
//
// FunctionCallExpression(is_null)
// |
// |- Signature => bool (typeof(CustomerID))
// |- args => {CustomerID}
//
//
// CustomerID ne null
// ==================
//
// UnaryExpression (not)
// |
// FunctionCallExpression(is_null)
// |
// |- Signature => bool (typeof(CustomerID))
// |- args => {CustomerID}
//
if (!$isCustomExpressionProvider) {
$arg = $left->typeIs($null) ? $right : $left;
$isNullFunctionDescription = new FunctionDescription('is_null', new Boolean(), array($arg->getType()));
switch ($expressionToken->Text) {
case ODataConstants::KEYWORD_EQUAL:
return new FunctionCallExpression($isNullFunctionDescription, array($arg));
break;
case ODataConstants::KEYWORD_NOT_EQUAL:
return new UnaryExpression(new FunctionCallExpression($isNullFunctionDescription, array($arg)), ExpressionType::NOT_LOGICAL, new Boolean());
break;
}
}
}
switch ($expressionToken->Text) {
case ODataConstants::KEYWORD_EQUAL:
return new RelationalExpression($left, $right, ExpressionType::EQUAL);
case ODataConstants::KEYWORD_NOT_EQUAL:
return new RelationalExpression($left, $right, ExpressionType::NOTEQUAL);
case ODataConstants::KEYWORD_GREATERTHAN:
return new RelationalExpression($left, $right, ExpressionType::GREATERTHAN);
case ODataConstants::KEYWORD_GREATERTHAN_OR_EQUAL:
return new RelationalExpression($left, $right, ExpressionType::GREATERTHAN_OR_EQUAL);
case ODataConstants::KEYWORD_LESSTHAN:
return new RelationalExpression($left, $right, ExpressionType::LESSTHAN);
default:
return new RelationalExpression($left, $right, ExpressionType::LESSTHAN_OR_EQUAL);
}
}
/**
* Merge two null check expression trees by removing duplicate nodes.
*
* @param AbstractExpression $nullCheckExpTree1 First expression.
* @param AbstractExpression $nullCheckExpTree2 Second expression.
*
* @return UnaryExpression or LogicalExpression
*/
private function _mergeNullableExpressionTrees($nullCheckExpTree1, $nullCheckExpTree2)
{
$this->_mapTable = array();
$this->_map($nullCheckExpTree1);
$this->_map($nullCheckExpTree2);
$expression = null;
$isNullFunctionDescription = null;
foreach ($this->_mapTable as $node) {
if ($expression == null) {
$expression = new UnaryExpression(new FunctionCallExpression(FunctionDescription::isNullCheckFunction($node->getType()), array($node)), ExpressionType::NOT_LOGICAL, new Boolean());
} else {
$expression = new LogicalExpression($expression, new UnaryExpression(new FunctionCallExpression(FunctionDescription::isNullCheckFunction($node->getType()), array($node)), ExpressionType::NOT_LOGICAL, new Boolean()), ExpressionType::AND_LOGICAL);
}
}
return $expression;
}
/**
* Function to create a nullable expression subtree for checking the
* nullablilty of parent (and current poperty optionally) properties
*
* @param boolean $includeMe Boolean flag indicating whether to include null
* check for this property along with parents
*
* @return AbstractExpression Instance of UnaryExpression, LogicalExpression
* or Null
*
*/
public function createNullableExpressionTree($includeMe)
{
$basePropertyExpression = $this;
while ($basePropertyExpression != null && $basePropertyExpression->parent != null) {
$basePropertyExpression = $basePropertyExpression->parent;
}
//This property is direct child of ResourceSet, no need to check
//nullability for direct ResourceSet properties
// ($c->CustomerID, $c->Order, $c->Address) unless $includeMe is true
if ($basePropertyExpression == $this) {
if ($includeMe) {
return new UnaryExpression(new FunctionCallExpression(FunctionDescription::isNullCheckFunction($basePropertyExpression->getType()), array($basePropertyExpression)), ExpressionType::NOT_LOGICAL, new Boolean());
}
return null;
}
//This property is a property of a complex type or resource reference
//$c->Order->OrderID, $c->Address->LineNumber,
// $c->complex1->complex2->primitveVar
//($c->Order != null),($c->Address != null),
// (($c->complex1 != null) && ($c->complex1->complex2 != null))
$expression = new UnaryExpression(new FunctionCallExpression(FunctionDescription::isNullCheckFunction($basePropertyExpression->getType()), array($basePropertyExpression)), ExpressionType::NOT_LOGICAL, new Boolean());
while ($basePropertyExpression->getChild() != null && $basePropertyExpression->getChild()->getChild() != null) {
$basePropertyExpression = $basePropertyExpression->getChild();
$expression2 = new UnaryExpression(new FunctionCallExpression(FunctionDescription::isNullCheckFunction($basePropertyExpression->getType()), array($basePropertyExpression)), ExpressionType::NOT_LOGICAL, new Boolean());
$expression = new LogicalExpression($expression, $expression2, ExpressionType::AND_LOGICAL);
}
if ($includeMe) {
$basePropertyExpression = $basePropertyExpression->getChild();
$expression2 = new UnaryExpression(new FunctionCallExpression(FunctionDescription::isNullCheckFunction($basePropertyExpression->getType()), array($basePropertyExpression)), ExpressionType::NOT_LOGICAL, new Boolean());
$expression = new LogicalExpression($expression, $expression2, ExpressionType::AND_LOGICAL);
}
return $expression;
}