private function validate()
{
if (empty($this->raw) or '' == trim($this->raw)) {
$this->valid = true;
return true;
}
// CAS keyval may not contain @ or $.
if (strpos($this->raw, '@') !== false || strpos($this->raw, '$') !== false) {
$this->errors = stack_string('illegalcaschars');
$this->valid = false;
return false;
}
// Subtle one: must protect things inside strings before we explode.
$str = $this->raw;
$strings = stack_utils::all_substring_strings($str);
foreach ($strings as $key => $string) {
$str = str_replace('"' . $string . '"', '[STR:' . $key . ']', $str);
}
$str = str_replace("\n", ';', $str);
$str = stack_utils::remove_comments($str);
$str = str_replace(';', "\n", $str);
$kvarray = explode("\n", $str);
foreach ($strings as $key => $string) {
foreach ($kvarray as $kkey => $kstr) {
$kvarray[$kkey] = str_replace('[STR:' . $key . ']', '"' . $string . '"', $kstr);
}
}
// 23/4/12 - significant changes to the way keyvals are interpreted. Use Maxima assignmentsm i.e. x:2.
$errors = '';
$valid = true;
$vars = array();
foreach ($kvarray as $kvs) {
$kvs = trim($kvs);
if ('' != $kvs) {
$cs = new stack_cas_casstring($kvs);
$cs->get_valid($this->security, $this->syntax, $this->insertstars);
$vars[] = $cs;
}
}
$this->session->add_vars($vars);
$this->valid = $this->session->get_valid();
$this->errors = $this->session->get_errors();
}
/**
* Extract the CAS commands from the string
*
* @access public
* @return bool false if no commands to extract, true if succeeds.
*/
private function extract_cas_commands()
{
// First check contains @s.
$count = preg_match_all('~(?<!@)@(?!@)~', $this->trimmedcastext, $notused);
if ($count == 0) {
// Nothing to do.
return null;
} else {
// Extract the CAS commands.
$temp = stack_utils::all_substring_between($this->trimmedcastext, '@', '@', true);
// Create array of commands matching with their labels.
$i = 0;
$valid = true;
$errors = '';
$cmdarray = array();
$labels = array();
$sessionkeys = array();
if (is_a($this->session, 'stack_cas_session')) {
$sessionkeys = $this->session->get_all_keys();
}
foreach ($temp as $cmd) {
// Trim of surrounding white space and CAS commands.
$cmd = stack_utils::trim_commands($cmd);
$cs = new stack_cas_casstring($cmd);
$cs->get_valid($this->security, $this->syntax, $this->insertstars);
do {
// ... make sure names are not already in use.
$key = 'caschat' . $i;
$i++;
} while (in_array($key, $sessionkeys));
$sesionkeys[] = $key;
$labels[] = $key;
$cs->set_key($key, true);
$cmdarray[] = $cs;
$valid = $valid && $cs->get_valid();
$errors .= $cs->get_errors();
}
if (!$valid) {
$this->valid = false;
$this->errors .= stack_string('stackCas_invalidCommand') . '</br>' . $errors;
}
if (!empty($cmdarray)) {
$newsession = $this->session;
if (null === $newsession) {
$newsession = new stack_cas_session($cmdarray, null, $this->seed);
} else {
$newsession->add_vars($cmdarray);
}
$this->session = $newsession;
// Now replace the commannds with their labels in the text.
$this->trimmedcastext = stack_utils::replace_between($this->trimmedcastext, '@', '@', $labels, true);
}
}
}
