Add path-related commands and update selection handling

src/commands/upsert-path-command.ts

@@ -0,0 +1,90 @@
+import { createOpaqueId } from "../core/ids";
+import { cloneEditorSelection, type EditorSelection } from "../core/selection";
+import type { ToolMode } from "../core/tool-mode";
+import {
+  cloneScenePath,
+  type ScenePath
+} from "../document/paths";
+
+import type { EditorCommand } from "./command";
+
+interface UpsertPathCommandOptions {
+  path: ScenePath;
+  label?: string;
+}
+
+function setSinglePathSelection(pathId: string): EditorSelection {
+  return {
+    kind: "paths",
+    ids: [pathId]
+  };
+}
+
+function createDefaultPathCommandLabel(isNewPath: boolean): string {
+  return isNewPath ? "Create path" : "Update path";
+}
+
+export function createUpsertPathCommand(
+  options: UpsertPathCommandOptions
+): EditorCommand {
+  const nextPath = cloneScenePath(options.path);
+  let previousPath: ScenePath | null = null;
+  let previousSelection: EditorSelection | null = null;
+  let previousToolMode: ToolMode | null = null;
+
+  return {
+    id: createOpaqueId("command"),
+    label: options.label ?? createDefaultPathCommandLabel(true),
+    execute(context) {
+      const currentDocument = context.getDocument();
+      const currentPath = currentDocument.paths[nextPath.id];
+
+      if (previousSelection === null) {
+        previousSelection = cloneEditorSelection(context.getSelection());
+      }
+
+      if (previousToolMode === null) {
+        previousToolMode = context.getToolMode();
+      }
+
+      if (previousPath === null && currentPath !== undefined) {
+        previousPath = cloneScenePath(currentPath);
+      }
+
+      context.setDocument({
+        ...currentDocument,
+        paths: {
+          ...currentDocument.paths,
+          [nextPath.id]: cloneScenePath(nextPath)
+        }
+      });
+      context.setSelection(setSinglePathSelection(nextPath.id));
+      context.setToolMode("select");
+    },
+    undo(context) {
+      const currentDocument = context.getDocument();
+      const nextPaths = {
+        ...currentDocument.paths
+      };
+
+      if (previousPath === null) {
+        delete nextPaths[nextPath.id];
+      } else {
+        nextPaths[nextPath.id] = cloneScenePath(previousPath);
+      }
+
+      context.setDocument({
+        ...currentDocument,
+        paths: nextPaths
+      });
+
+      if (previousSelection !== null) {
+        context.setSelection(previousSelection);
+      }
+
+      if (previousToolMode !== null) {
+        context.setToolMode(previousToolMode);
+      }
+    }
+  };
+}