+<?php
+
+namespace Drupal\devel\Form;
+
+use Drupal\Component\Serialization\Exception\InvalidDataTypeException;
+use Drupal\Component\Serialization\Yaml;
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\State\StateInterface;
+use Drupal\Core\Url;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Form API form to edit a state.
+ */
+class SystemStateEdit extends FormBase {
+
+ /**
+ * The state store.
+ *
+ * @var \Drupal\Core\State\StateInterface
+ */
+ protected $state;
+
+ /**
+ * Constructs a new SystemStateEdit object.
+ *
+ * @param \Drupal\Core\State\StateInterface $state
+ * The state service.
+ */
+ public function __construct(StateInterface $state) {
+ $this->state = $state;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public static function create(ContainerInterface $container) {
+ return new static(
+ $container->get('state')
+ );
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getFormId() {
+ return 'devel_state_system_edit_form';
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function buildForm(array $form, FormStateInterface $form_state, $state_name = '') {
+ // Get the old value
+ $old_value = $this->state->get($state_name);
+
+ if (!isset($old_value)) {
+ drupal_set_message(t('State @name does not exist in the system.', array('@name' => $state_name)), 'warning');
+ return;
+ }
+
+ // Only simple structures are allowed to be edited.
+ $disabled = !$this->checkObject($old_value);
+
+ if ($disabled) {
+ drupal_set_message(t('Only simple structures are allowed to be edited. State @name contains objects.', array('@name' => $state_name)), 'warning');
+ }
+
+ // First we will show the user the content of the variable about to be edited.
+ $form['value'] = array(
+ '#type' => 'item',
+ '#title' => $this->t('Current value for %name', array('%name' => $state_name)),
+ '#markup' => kpr($old_value, TRUE),
+ );
+
+ $transport = 'plain';
+
+ if (!$disabled && is_array($old_value)) {
+ try {
+ $old_value = Yaml::encode($old_value);
+ $transport = 'yaml';
+ }
+ catch (InvalidDataTypeException $e) {
+ drupal_set_message(t('Invalid data detected for @name : %error', array('@name' => $state_name, '%error' => $e->getMessage())), 'error');
+ return;
+ }
+ }
+
+ // Store in the form the name of the state variable
+ $form['state_name'] = array(
+ '#type' => 'value',
+ '#value' => $state_name,
+ );
+ // Set the transport format for the new value. Values:
+ // - plain
+ // - yaml
+ $form['transport'] = array(
+ '#type' => 'value',
+ '#value' => $transport,
+ );
+
+ $form['new_value'] = array(
+ '#type' => 'textarea',
+ '#title' => $this->t('New value'),
+ '#default_value' => $disabled ? '' : $old_value,
+ '#disabled' => $disabled,
+ '#rows' => 15,
+ );
+
+ $form['actions'] = array('#type' => 'actions');
+ $form['actions']['submit'] = array(
+ '#type' => 'submit',
+ '#value' => $this->t('Save'),
+ '#disabled' => $disabled,
+ );
+ $form['actions']['cancel'] = array(
+ '#type' => 'link',
+ '#title' => $this->t('Cancel'),
+ '#url' => Url::fromRoute('devel.state_system_page')
+ );
+
+ return $form;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function validateForm(array &$form, FormStateInterface $form_state) {
+ $values = $form_state->getValues();
+
+ if ($values['transport'] == 'yaml') {
+ // try to parse the new provided value
+ try {
+ $parsed_value = Yaml::decode($values['new_value']);
+ $form_state->setValue('parsed_value', $parsed_value);
+ }
+ catch (InvalidDataTypeException $e) {
+ $form_state->setErrorByName('new_value', $this->t('Invalid input: %error', array('%error' => $e->getMessage())));
+ }
+ }
+ else {
+ $form_state->setValue('parsed_value', $values['new_value']);
+ }
+
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function submitForm(array &$form, FormStateInterface $form_state) {
+ // Save the state
+ $values = $form_state->getValues();
+ $this->state->set($values['state_name'], $values['parsed_value']);
+
+ $form_state->setRedirectUrl(Url::fromRoute('devel.state_system_page'));
+
+ drupal_set_message($this->t('Variable %variable was successfully edited.', array('%variable' => $values['state_name'])));
+ $this->logger('devel')->info('Variable %variable was successfully edited.', array('%variable' => $values['state_name']));
+ }
+
+ /**
+ * Helper function to determine if a variable is or contains an object.
+ *
+ * @param $data
+ * Input data to check
+ *
+ * @return bool
+ * TRUE if the variable is not an object and does not contain one.
+ */
+ protected function checkObject($data) {
+ if (is_object($data)) {
+ return FALSE;
+ }
+ if (is_array($data)) {
+ // If the current object is an array, then check recursively.
+ foreach ($data as $value) {
+ // If there is an object the whole container is "contaminated"
+ if (!$this->checkObject($value)) {
+ return FALSE;
+ }
+ }
+ }
+
+ // All checks pass
+ return TRUE;
+ }
+
+}