/**
* This function will replace any parameters in a string with their value.
* Parameters are defined by being prefixed by a $ character. In certain
* situations, the parameter will be surrounded by {}, which Symphony
* takes to mean, evaluate this parameter to a value, other times it will be
* omitted which is usually used to indicate that this parameter exists
*
* @param string $value
* The string with the parameters that need to be evaluated
* @param array $env
* The environment variables from the Frontend class which includes
* any params set by Symphony or Events or by other Datasources
* @param boolean $includeParenthesis
* Parameters will sometimes not be surrounded by {}. If this is the case
* setting this parameter to false will make this function automatically add
* them to the parameter. By default this is true, which means all parameters
* in the string already are surrounded by {}
* @param boolean $escape
* If set to true, the resulting value will be `urlencode`'d before being returned.
* By default this is false
* @return string
* The string will all parameters evaluated. If a parameter was not found, it will
* not be replaced at all.
*/
public function __processParametersInString($value, array $env, $includeParenthesis = true, $escape = false)
{
if (trim($value) == '') {
return null;
}
if (!$includeParenthesis) {
$value = '{' . $value . '}';
}
if (preg_match_all('@{([^}]+)}@i', $value, $matches, PREG_SET_ORDER)) {
foreach ($matches as $match) {
list($source, $cleaned) = $match;
$replacement = null;
$bits = preg_split('/:/', $cleaned, -1, PREG_SPLIT_NO_EMPTY);
foreach ($bits as $param) {
if ($param[0] != '$') {
$replacement = $param;
break;
}
$param = trim($param, '$');
$replacement = Datasource::findParameterInEnv($param, $env);
if (is_array($replacement)) {
$replacement = array_map(array('Datasource', 'escapeCommas'), $replacement);
if (count($replacement) > 1) {
$replacement = implode(',', $replacement);
} else {
$replacement = end($replacement);
}
}
if (!empty($replacement)) {
break;
}
}
if ($escape == true) {
$replacement = urlencode($replacement);
}
$value = str_replace($source, $replacement, $value);
}
}
return $value;
}
