[doc] Update the ADR to display selection dialog as tree

Signed-off-by: Florian Barbin <[email protected]>

doc/adrs/153_selection_dialog_tree_view.adoc

@@ -44,17 +44,28 @@ type SelectionObject {
 
 === Preferred option
 
+==== View model 
+
 The specifier will choose whether the objects returned by the candidates expression will be displayed as a tree or as a flat list. 
 
 The `SelectionDialogDescription` from the Diagram View model will have two additional boolean attributes:
 
  * `displayedAsTree`: to indicate whether the dialog layout should be a tree.
- * `expendedAtOpening`: to indicate if the tree should be expended by default (that means all tree items are expended at opening)
+ * `expandedAtOpening`: to indicate if the tree should be expanded by default (that means all tree items are expanded at opening)
+
+==== Backend and GraphQL API
+
+In addition, the Selection computed by the `SelectionRender` by the server will now return the containment information.
+
+Since the tree depth is not known by the frontend beforehand, the backend needs to return the whole tree items in a flat way.
 
-In addition, the Selection computed by the `SelectionRender` by the server will now return the containment information:
+The GraphQL subscription query will thus have a fixed depth. The containment information will be owned by a field called `parentId`.
 
- * A `SelectionObject` can contain `SelectionObject` as children.
+To do so, we will keep the same GraphQL structure but with the following changes:
+
+ * A `SelectionObject` will have a `parentId` field (optional), that will be a reference to another `SelectionObject#id` field.
  * A `SelectionObject` will contain the information whether it can be selected or not in order to differentiate elements from the candidatesExpression to the hierarchical nodes.
+ * The `Selection` will also contains the information whether the dialog should be displayed as a tree or not and if we should expand all nodes at opening.
 
 Thus, the GraphQL API will evolved as following:
 
@@ -66,14 +77,14 @@ type Selection implements Representation {
   message: String
   objects: [SelectionObject!]!
   displayedAsTree: Boolean!
-  expendedAtOpening: Boolean!
+  expandedAtOpening: Boolean!
 }
 
 type SelectionObject {
   id: ID!
   label: String!
   iconURL: [String!]!
-  objects: [SelectionObject!]!
+  parentId: String
   isSelectable: Boolean!
 }
 ```
@@ -107,6 +118,8 @@ Root
   |_ (F)
 ```
 
+==== Frontend
+
 Elements that are not selectable (out of the computed candidates set) will by faded in the same way than the reference widget semantic browser do:
 
 image:images/153/referenceWidgetSemanticBrowser.png[Reference Widget Semantic Browser, 50%]
@@ -139,6 +152,20 @@ We will rely on the MaterialUI `TreeItem` and `TreeView` in the same way than th
   );
 ```
 
+If the Selection is refreshed by the backend, following a semantic change from another client for instance, a new Selection from the subscription will be received by the SelectionDialog and trigger the component rerendering.
+
+If the end-user has changed the expanded state, we want to keep them expanded in that situation. 
+
+To do so, We will modify the SelectionDialog state machine as follow:
+
+ * A new `expandedSelectionObjectIds : string[]` will be added in the `SelectionDialogContext`.
+ * A new event `HandleExpandUpdatedEvent` = { type: 'HANDLE_EXPAND_UPDATED'; expandedObjectId: string }; This event will add or remove the expandedObjectId from the expandedSelectionObjectIds array.
+
+A TreeItem will be expanded if:
+
+ * The expandedAtOpening is activated: in that case, the `expandedSelectionObjectIds` will be initialized with all selectedObject ids.
+ * The user expanded the item manually.
+
 === Second option
 
 The second option but not the preferred one, consists in relying on the TreeRepresentation.