1 files changed, 45 insertions, 0 deletions

diff --git a/language-web/src/main/js/xtext/ValidationService.ts b/language-web/src/main/js/xtext/ValidationService.ts
new file mode 100644
index 00000000..8e4934ac
--- /dev/null
+++ b/language-web/src/main/js/xtext/ValidationService.ts
@@ -0,0 +1,45 @@
+import type { Diagnostic } from '@codemirror/lint';
+
+import type { EditorStore } from '../editor/EditorStore';
+import type { UpdateService } from './UpdateService';
+import { getLogger } from '../utils/logger';
+import { isValidationResult } from './xtextServiceResults';
+
+const log = getLogger('xtext.ValidationService');
+
+export class ValidationService {
+  private readonly store: EditorStore;
+
+  private readonly updateService: UpdateService;
+
+  constructor(store: EditorStore, updateService: UpdateService) {
+    this.store = store;
+    this.updateService = updateService;
+  }
+
+  onPush(push: unknown): void {
+    if (!isValidationResult(push)) {
+      log.error('Invalid validation result', push);
+      return;
+    }
+    const allChanges = this.updateService.computeChangesSinceLastUpdate();
+    const diagnostics: Diagnostic[] = [];
+    push.issues.forEach(({
+      offset,
+      length,
+      severity,
+      description,
+    }) => {
+      if (severity === 'ignore') {
+        return;
+      }
+      diagnostics.push({
+        from: allChanges.mapPos(offset),
+        to: allChanges.mapPos(offset + length),
+        severity,
+        message: description,
+      });
+    });
+    this.store.updateDiagnostics(diagnostics);
+  }
+}