Visual Console Client: WIP work on the line item

Former-commit-id: 0f40636ebd9d01ccdf618579e5e7c25be015ad04

visual_console/src/Item.ts

@@ -45,16 +45,6 @@ export interface ItemProps extends Position, Size {
   aclGroupId: number | null;
 }
 
-interface VisualConsoleLineItemProps {
-  readonly id: number;
-  readonly type: 13;
-  isOnTop: boolean;
-  startPosition: Position;
-  endPosition: Position;
-  borderWidth: string;
-  borderColor: string;
-}
-
 // FIXME: Fix type compatibility.
 export interface ItemClickEvent<Props extends ItemProps> {
   // data: Props;

visual_console/src/items/Line.ts

@@ -0,0 +1,67 @@
+import { UnknownObject, Position } from "../types";
+import { parseIntOr, notEmptyStringOr } from "../lib";
+import Item, { ItemType, ItemProps, itemBasePropsDecoder } from "../Item";
+
+interface LineProps extends ItemProps {
+  // Overrided properties.
+  readonly type: ItemType.LINE_ITEM;
+  label: null;
+  isLinkEnabled: false;
+  parentId: null;
+  aclGroupId: null;
+  // Clear Position & Size.
+  x: 0;
+  y: 0;
+  width: 0;
+  height: 0;
+  // Custom properties.
+  startPosition: Position;
+  endPosition: Position;
+  lineWidth: number;
+  color: string | null;
+}
+
+/**
+ * Build a valid typed object from a raw object.
+ * This will allow us to ensure the type safety.
+ *
+ * @param data Raw object.
+ * @return An object representing the item props.
+ * @throws Will throw a TypeError if some property
+ * is missing from the raw object or have an invalid type.
+ */
+export function linePropsDecoder(data: UnknownObject): LineProps | never {
+  return {
+    ...itemBasePropsDecoder(data), // Object spread. It will merge the properties of the two objects.
+    type: ItemType.LINE_ITEM,
+    label: null,
+    isLinkEnabled: false,
+    parentId: null,
+    aclGroupId: null,
+    // Clear Position & Size.
+    x: 0,
+    y: 0,
+    width: 0,
+    height: 0,
+    // Custom properties.
+    startPosition: {
+      x: 0,
+      y: 0
+    },
+    endPosition: {
+      x: 0,
+      y: 0
+    },
+    lineWidth: parseIntOr(data.lineWidth, 0),
+    color: notEmptyStringOr(data.color, null)
+  };
+}
+
+export default class Line extends Item<LineProps> {
+  public createDomElement(): HTMLElement {
+    const line: HTMLDivElement = document.createElement("div");
+    line.className = "line";
+
+    return line;
+  }
+}