/**
* Get a list of the PRT notes that should be present for a given PRT.
* @param string $prtname the name of a PRT.
* @return array list of nodes that should be present in the form definitino for this PRT.
*/
protected function get_prt_graph($prtname)
{
if (array_key_exists($prtname, $this->prtgraph)) {
return $this->prtgraph[$prtname];
}
// If the form has been submitted and is being redisplayed, and this is
// an existing PRT, base things on the submitted data.
$submitted = optional_param_array($prtname . 'truenextnode', null, PARAM_RAW);
if ($submitted) {
$truescoremode = optional_param_array($prtname . 'truescoremode', null, PARAM_RAW);
$truescore = optional_param_array($prtname . 'truescore', null, PARAM_RAW);
$falsenextnode = optional_param_array($prtname . 'falsenextnode', null, PARAM_RAW);
$falsescoremode = optional_param_array($prtname . 'falsescoremode', null, PARAM_RAW);
$falsescore = optional_param_array($prtname . 'falsescore', null, PARAM_RAW);
$graph = new stack_abstract_graph();
$deletednode = null;
$lastkey = -1;
foreach ($submitted as $key => $truenextnode) {
if (optional_param($prtname . 'nodedelete' . $key, false, PARAM_BOOL)) {
// Slightly odd to register the button here, especially since
// now this node has been deleted, this button will not exist,
// but anyway this works, and in necessary to stop the form
// from being submitted.
$this->_form->registerNoSubmitButton($prtname . 'nodedelete' . $key);
// For deleted nodes, we add them to the tree anyway, and
// then remove them again below. We have to do it that way
// because we also need to delete links that point to the
// deleted node.
$deletednode = $key;
}
if ($truenextnode == -1 || !array_key_exists($truenextnode, $submitted)) {
$left = null;
} else {
$left = $truenextnode + 1;
}
if ($falsenextnode[$key] == -1 || !array_key_exists($falsenextnode[$key], $submitted)) {
$right = null;
} else {
$right = $falsenextnode[$key] + 1;
}
$graph->add_node($key + 1, $left, $right, $truescoremode[$key] . round($truescore[$key], 2), $falsescoremode[$key] . round($falsescore[$key], 2), '#fgroup_id_' . $prtname . 'node_' . $key);
$lastkey = max($lastkey, $key);
}
if (optional_param($prtname . 'nodeadd', false, PARAM_BOOL)) {
$graph->add_node($lastkey + 2, null, null, '+0', '-0', '#fgroup_id_' . $prtname . 'node_' . $lastkey + 1);
}
if (!is_null($deletednode)) {
$graph->remove_node($deletednode + 1);
}
$graph->layout();
$this->prtgraph[$prtname] = $graph;
return $graph;
}
// Otherwise, if an existing question is being edited, and this is an
// existing PRT, base things on the existing question definition.
if (!empty($this->question->prts[$prtname]->nodes)) {
$graph = new stack_abstract_graph();
foreach ($this->question->prts[$prtname]->nodes as $node) {
if ($node->truenextnode == -1) {
$left = null;
} else {
$left = $node->truenextnode + 1;
}
if ($node->falsenextnode == -1) {
$right = null;
} else {
$right = $node->falsenextnode + 1;
}
$graph->add_node($node->nodename + 1, $left, $right, $node->truescoremode . round($node->truescore, 2), $node->falsescoremode . round($node->falsescore, 2), '#fgroup_id_' . $prtname . 'node_' . $node->nodename);
}
$graph->layout();
$this->prtgraph[$prtname] = $graph;
return $graph;
}
// Otherwise, it is a new PRT. Just one node.
$graph = new stack_abstract_graph();
$graph->add_node('1', null, null, '=1', '=0', '#fgroup_id_' . $prtname . 'node_0');
$graph->layout();
$this->prtgraph[$prtname] = $graph;
return $graph;
}
