#2799361 - Add drag and drop to actions and conditions from #2648334.

config/schema/rules.expression.schema.yml

@@ -7,6 +7,9 @@ rules_expression:
   uuid:
     type: string
     label: 'UUID'
+  weight:
+    type: integer
+    label: 'Weight'
 
 rules_expression.rules_condition:
   type: rules_expression
@@ -18,6 +21,9 @@ rules_expression.rules_condition:
     uuid:
       type: string
       label: 'UUID'
+    weight:
+      type: integer
+      label: 'Weight'
     condition_id:
       type: string
       label: 'Condition plugin ID'
@@ -47,6 +53,9 @@ rules_expression.rules_action:
     uuid:
       type: string
       label: 'UUID'
+    weight:
+      type: integer
+      label: 'Weight'
     action_id:
       type: string
       label: 'Action plugin ID'
@@ -73,6 +82,9 @@ rules_expression.rules_and:
     uuid:
       type: string
       label: 'UUID'
+    weight:
+      type: integer
+      label: 'Weight'
     negate:
       type: boolean
       label: 'Negate'
@@ -92,6 +104,9 @@ rules_expression.rules_action_set:
     uuid:
       type: string
       label: 'UUID'
+    weight:
+      type: integer
+      label: 'Weight'
     actions:
       type: sequence
       label: 'Actions'
@@ -108,6 +123,9 @@ rules_expression.rules_rule:
     uuid:
       type: string
       label: 'UUID'
+    weight:
+      type: integer
+      label: 'Weight'
     conditions:
       type: rules_expression.[id]
       label: 'Conditions'

src/Engine/ExpressionBase.php

@@ -37,6 +37,13 @@ abstract class ExpressionBase extends PluginBase implements ExpressionInterface
    */
   protected $uuid;
 
+  /**
+   * The weight of this expression.
+   *
+   * @var integer
+   */
+  protected $weight;
+
   /**
    * Constructor.
    *
@@ -71,6 +78,7 @@ public function getConfiguration() {
     return [
       'id' => $this->getPluginId(),
       'uuid' => $this->uuid,
+      'weight' => $this->weight,
     ] + $this->configuration;
   }
 
@@ -82,6 +90,13 @@ public function setConfiguration(array $configuration) {
     if (isset($configuration['uuid'])) {
       $this->uuid = $configuration['uuid'];
     }
+    if (isset($configuration['weight'])) {
+      $this->weight = $configuration['weight'];
+    }
+    else {
+      $this->weight = 0;
+    }
+
     return $this;
   }
 
@@ -148,4 +163,31 @@ public function setUuid($uuid) {
     $this->uuid = $uuid;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getWeight() {
+    return $this->weight;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setWeight($weight) {
+    $this->weight = $weight;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function expressionSortHelper(ExpressionInterface $a, ExpressionInterface $b) {
+    $a_weight = $a->getWeight();
+    $b_weight = $b->getWeight();
+    if ($a_weight == $b_weight) {
+      return 0;
+    }
+
+    return ($a_weight < $b_weight) ? -1 : 1;
+  }
+
 }

src/Engine/ExpressionInterface.php

@@ -79,6 +79,37 @@ public function getUuid();
    */
   public function setUuid($uuid);
 
+  /**
+   * Returns the weight of this expression.
+   *
+   * @return int
+   *   The weight of this expression.
+   */
+  public function getWeight();
+
+  /**
+   * Sets the weight of this expression in an expression tree.
+   *
+   * @param int $weight
+   *   The weight to set.
+   */
+  public function setWeight($weight);
+
+  /**
+   * Sorts an array of expressions by 'weight' property.
+   *
+   * Callback for uasort().
+   *
+   * @param \Drupal\rules\Engine\ExpressionInterface $a
+   *   First item for comparison.
+   * @param \Drupal\rules\Engine\ExpressionInterface $b
+   *   Second item for comparison.
+   *
+   * @return int
+   *   The comparison result for uasort().
+   */
+  public function expressionSortHelper(ExpressionInterface $a, ExpressionInterface $b);
+
   /**
    * Verifies that this expression is configured correctly.
    *

src/Form/Expression/ActionContainerForm.php

@@ -39,31 +39,75 @@ public function form(array $form, FormStateInterface $form_state) {
     ];
 
     $form['action_table']['table'] = [
-      '#theme' => 'table',
-      '#caption' => $this->t('Actions'),
-      '#header' => [$this->t('Elements'), $this->t('Operations')],
-      '#empty' => t('None'),
+      '#type' => 'table',
+      '#header' => [
+        $this->t('Elements'),
+        $this->t('Weight'),
+        [
+          'data' => $this->t('Operations'),
+          'colspan' => 3,
+        ],
+      ],
+      '#attributes' => [
+        'id' => 'rules_actions_table',
+      ],
+      '#tabledrag' => [
+        [
+          'action' => 'order',
+          'relationship' => 'sibling',
+          'group' => 'action-weight',
+        ],
+      ],
     ];
 
+    $form['action_table']['table']['#empty'] = $this->t('None');
+
+    // Get hold of actions.
+    // @todo See if we can add getExpressions method of ExpressionContainerBase.
+    $actions = [];
     foreach ($this->actionSet as $action) {
-      $form['action_table']['table']['#rows'][] = [
-        'element' => $action->getLabel(),
-        'operations' => [
-          'data' => [
-            '#type' => 'dropbutton',
-            '#links' => [
-              'edit' => [
-                'title' => $this->t('Edit'),
-                'url' => $this->getRulesUiHandler()->getUrlFromRoute('expression.edit', [
-                  'uuid' => $action->getUuid(),
-                ]),
-              ],
-              'delete' => [
-                'title' => $this->t('Delete'),
-                'url' => $this->getRulesUiHandler()->getUrlFromRoute('expression.delete', [
-                  'uuid' => $action->getUuid(),
-                ]),
-              ],
+      $actions[] = $action;
+    }
+
+    // Sort actions by weight.
+    @uasort($actions, [$this->actionSet, 'expressionSortHelper']);
+
+    foreach ($actions as $action) {
+      /* @var $action \Drupal\rules\Engine\ExpressionInterface */
+      $uuid = $action->getUuid();
+      $row = &$form['action_table']['table'][$uuid];
+
+      // TableDrag: Mark the table row as draggable.
+      $row['#attributes']['class'][] = 'draggable';
+
+      // TableDrag: Sort the table row according to its existing weight.
+      $row['#weight'] = $action->getWeight();
+      $row['title'] = ['#markup' => $action->getLabel()];
+
+      $row['weight'] = [
+        '#type' => 'weight',
+        '#delta' => 50,
+        '#default_value' => $action->getWeight(),
+        '#attributes' => ['class' => ['action-weight']],
+      ];
+
+      // Operations (dropbutton) column.
+      $rules_ui_handler = $this->getRulesUiHandler();
+      $row['operations'] = [
+        'data' => [
+          '#type' => 'dropbutton',
+          '#links' => [
+            'edit' => [
+              'title' => $this->t('Edit'),
+              'url' => $rules_ui_handler->getUrlFromRoute('expression.edit', [
+                'uuid' => $uuid,
+              ]),
+            ],
+            'delete' => [
+              'title' => $this->t('Delete'),
+              'url' => $rules_ui_handler->getUrlFromRoute('expression.delete', [
+                'uuid' => $uuid,
+              ]),
             ],
           ],
         ],
@@ -85,4 +129,24 @@ public function form(array $form, FormStateInterface $form_state) {
     return $form;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    $values = $form_state->getValue('table');
+    $component = $this->getRulesUiHandler()->getComponent();
+    /* @var $rule_expression \Drupal\rules\Plugin\RulesExpression\Rule */
+    $rule_expression = $component->getExpression();
+
+    if ($values) {
+      foreach ($values as $uuid => $expression) {
+        $action = $rule_expression->getExpression($uuid);
+        $action->setWeight($expression['weight']);
+        $action->setConfiguration($action->getConfiguration());
+      }
+    }
+
+    $this->getRulesUiHandler()->updateComponent($component);
+  }
+
 }