/**
* Create the SQL of a case expression
* @param zibo\library\database\manipulation\expression\CaseExpression $case
* @return string SQL of the case expression
*/
protected function parseCaseExpression(CaseExpression $case, $useAlias = true)
{
$sql = 'CASE ';
$when = $case->getWhen();
foreach ($when as $w) {
$whenCondition = $this->parseCondition($w->getCondition(), $useAlias);
$whenExpression = $this->parseExpression($w->getExpression(), $useAlias);
$sql .= 'WHEN ' . $whenCondition . ' ';
$sql .= 'THEN ' . $whenExpression . ' ';
}
$defaultExpression = $case->getDefaultExpression();
if ($defaultExpression) {
$sql .= 'ELSE ' . $this->parseExpression($defaultExpression, $useAlias) . ' ';
}
$sql = '(' . $sql . 'END)';
$alias = $case->getAlias();
if ($useAlias && $alias) {
$sql .= ' AS ' . $this->connection->quoteIdentifier($alias);
}
return $sql;
}
/**
* Parses the provided case into a database case expression
* @param string $case String of a case expression
* @return boolean|zibo\library\database\manipulation\expression\CaseExpression false if the
* provided case expression could not be parsed, the case expression otherwise
* @todo implement this function
*/
private function parseCase($case)
{
if (!preg_match(self::REGEX_CASE, $case)) {
return false;
}
if (strpos($case, ' AS ') !== false) {
list($case, $alias) = explode(' AS ', $case);
} else {
$alias = null;
}
if (substr($case, 0, 1) == '(' && substr($case, -1) == ')') {
$case = substr($case, 1, -1);
}
$case = substr($case, 5, -4);
if (strpos($case, ' ELSE ') !== false) {
list($conditions, $else) = explode(' ELSE ', $case);
} else {
$condition = $case;
$else = null;
}
$conditions = explode('WHEN', $conditions);
if (!$conditions) {
return false;
}
$case = new CaseExpression();
if ($alias) {
$case->setAlias($alias);
}
if ($else) {
$case->setDefaultExpression($this->parseExpression($else));
}
foreach ($conditions as $condition) {
$condition = trim($condition);
if (!$condition) {
continue;
}
list($condition, $value) = explode(' THEN ', $condition);
$condition = $this->parseCondition(new ModelExpression($condition));
$value = $this->parseExpression($value);
$case->addWhen($condition, $value);
}
return $case;
}
/**
* Adds the join to localize the data of the model to the statement
* @return null
*/
private function addLocalizeJoin()
{
$joinCondition = $this->createLocalizeCondition($this->tables[self::ALIAS_SELF], $this->tables[self::ALIAS_SELF_LOCALIZED]);
if ($this->includeUnlocalizedData) {
$joinType = JoinExpression::TYPE_LEFT;
$localeField = new FieldExpression(LocalizedModel::FIELD_LOCALE, $this->tables[self::ALIAS_SELF_LOCALIZED], self::ALIAS_SELF . self::ALIAS_SEPARATOR . LocalizedModel::FIELD_LOCALE);
$this->statement->addField($localeField);
$isLocalizedCondition = new SimpleCondition($localeField, new ScalarExpression(null), Condition::OPERATOR_IS);
$isLocalizedCase = new CaseExpression();
$isLocalizedCase->setAlias(self::ALIAS_IS_LOCALIZED);
$isLocalizedCase->setDefaultExpression(new ScalarExpression(1));
$isLocalizedCase->addWhen($isLocalizedCondition, new ScalarExpression(0));
$this->statement->addField($isLocalizedCase);
if ($this->addIsLocalizedOrder) {
$order = new OrderExpression(new FieldExpression(self::ALIAS_IS_LOCALIZED), OrderExpression::DIRECTION_DESC);
$this->statement->addOrderBy($order);
}
} else {
$joinType = JoinExpression::TYPE_INNER;
}
$join = new JoinExpression($joinType, $this->tables[self::ALIAS_SELF_LOCALIZED], $joinCondition);
$this->tables[self::ALIAS_SELF]->addJoin($join);
}
