1 files changed, 67 insertions, 0 deletions
diff --git a/tools/language-server/src/plugins/css/features/getIdClassCompletion.ts b/tools/language-server/src/plugins/css/features/getIdClassCompletion.ts
new file mode 100644
index 000000000..45acb5ad6
--- /dev/null
+++ b/tools/language-server/src/plugins/css/features/getIdClassCompletion.ts
@@ -0,0 +1,67 @@
+import { CompletionItem, CompletionItemKind, CompletionList } from 'vscode-languageserver';
+import { AttributeContext } from '../../../core/documents/parseHtml';
+import { CSSDocument } from '../CSSDocument';
+
+export function getIdClassCompletion(cssDoc: CSSDocument, attributeContext: AttributeContext): CompletionList | null {
+  const collectingType = getCollectingType(attributeContext);
+
+  if (!collectingType) {
+    return null;
+  }
+  const items = collectSelectors(cssDoc.stylesheet as CSSNode, collectingType);
+
+  console.log('getIdClassCompletion items', items.length);
+  return CompletionList.create(items);
+}
+
+function getCollectingType(attributeContext: AttributeContext): number | undefined {
+  if (attributeContext.inValue) {
+    if (attributeContext.name === 'class') {
+      return NodeType.ClassSelector;
+    }
+    if (attributeContext.name === 'id') {
+      return NodeType.IdentifierSelector;
+    }
+  } else if (attributeContext.name.startsWith('class:')) {
+    return NodeType.ClassSelector;
+  }
+}
+
+/**
+ * incomplete see
+ * https://github.com/microsoft/vscode-css-languageservice/blob/master/src/parser/cssNodes.ts#L14
+ * The enum is not exported. we have to update this whenever it changes
+ */
+export enum NodeType {
+  ClassSelector = 14,
+  IdentifierSelector = 15,
+}
+
+export type CSSNode = {
+  type: number;
+  children: CSSNode[] | undefined;
+  getText(): string;
+};
+
+export function collectSelectors(stylesheet: CSSNode, type: number) {
+  const result: CSSNode[] = [];
+  walk(stylesheet, (node) => {
+    if (node.type === type) {
+      result.push(node);
+    }
+  });
+
+  return result.map(
+    (node): CompletionItem => ({
+      label: node.getText().substring(1),
+      kind: CompletionItemKind.Keyword,
+    })
+  );
+}
+
+function walk(node: CSSNode, callback: (node: CSSNode) => void) {
+  callback(node);
+  if (node.children) {
+    node.children.forEach((node) => walk(node, callback));
+  }
+}