Suggest brand IDs after brand: and place unknown-brand errors on their line

- Completion for brand values in .archify (YAML) and Archify JSON sources,
  from the bundled brand-marks/catalog.json (107 marks); aliases and
  product names match, so "kafka" offers apache-kafka
- brand/unknown diagnostics carry their JSON pointer only at the start of
  the message; use it when subject.path is missing, so the error lands on
  the brand line instead of the top of the file
- Unit tests for catalog loading, value detection and pointer fallback;
  integration checks for completion and diagnostic placement

Closes #5

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+## Unreleased
+
+- **Brand completion:** after `brand:` in `.archify` files and Archify JSON sources, the editor suggests the 107 built-in brand IDs with their product names. Aliases and product names match too (`kafka` → `apache-kafka`, `postgres` → `postgresql`).
+- **Unknown brands are underlined on their own line.** Archify reports these without a location, so they used to appear at the top of the file.
+
 ## 0.4.1 — 2026-10-04
 
 - The new-diagram command is now titled **New Diagram Archify…** everywhere, including the Explorer folder menu, where it read *New Diagram…*.

README.md

@@ -50,6 +50,7 @@ Archify's own JSON naming, `name.architecture.json`, `name.workflow.json` and so
 - **Live preview**: for Archify's `*.architecture.json`-style files, or any JSON with a `diagram_type`. Use the preview button in the editor title, <kbd>Cmd/Ctrl+K V</kbd> (to the side) or <kbd>Cmd/Ctrl+Shift+V</kbd>. The preview keeps the focus and route you selected (`#focus=…`, `#route=…`) when it re-renders.
 - **HTML viewer**: right-click a rendered `.html` file and choose **Open in Archify Viewer**, or use *Reopen Editor With… → Archify Diagram Viewer*. For Archify HTML already open as text, a button appears in the editor title. The viewer reloads when the file changes on disk.
 - **Problems**: YAML syntax errors, plus `archify validate`'s schema, layout and evidence problems, appear at the matching line of the source.
+- **Brand logos**: after `brand:` the editor suggests Archify's built-in brand IDs (PostgreSQL, Redis, Kafka, Docker, …). Typing an alias or product name finds them too, so `kafka` offers `apache-kafka`. An unknown brand is reported on its own line.
 - **Schema help**: completion and hover come from Archify's own schemas: built in for the JSON files, and through the YAML extension for `.archify` files.
 - **Source links**: in source-backed diagrams, clicking a source reference opens that file and line range in the editor. If the file is not in the workspace, the web link opens instead.
 - **Export**: the diagram's own Export menu (PNG, SVG, share card, …) saves through a VS Code save dialog.

src/brandCompletion.ts

@@ -0,0 +1,48 @@
+import path from 'node:path';
+import * as vscode from 'vscode';
+import { Brand, brandValueAt, loadBrandCatalog } from './brands';
+import { isArchifyFile } from './detect';
+import { log } from './runtime';
+
+const JSON_SOURCES = '**/*.{architecture,workflow,sequence,dataflow,lifecycle}.json';
+
+export const BRAND_COMPLETION_SELECTOR: vscode.DocumentSelector = [
+  { pattern: '**/*.archify' },
+  { language: 'json', pattern: JSON_SOURCES },
+  { language: 'jsonc', pattern: JSON_SOURCES },
+];
+
+/** Suggests Archify's built-in brand IDs for `brand` values. */
+export class BrandCompletionProvider implements vscode.CompletionItemProvider {
+  private brands: Brand[] | undefined;
+
+  constructor(private readonly extensionPath: string) {}
+
+  private catalog(): Brand[] {
+    if (!this.brands) {
+      try {
+        this.brands = loadBrandCatalog(path.join(this.extensionPath, 'vendor', 'archify', 'brand-marks', 'catalog.json'));
+      } catch (error) {
+        log().error(`Could not read the Archify brand catalog: ${error instanceof Error ? error.message : String(error)}`);
+        this.brands = [];
+      }
+    }
+    return this.brands;
+  }
+
+  provideCompletionItems(document: vscode.TextDocument, position: vscode.Position): vscode.CompletionItem[] | undefined {
+    const linePrefix = document.lineAt(position.line).text.slice(0, position.character);
+    const value = brandValueAt(linePrefix, isArchifyFile(document.fileName) ? 'yaml' : 'json');
+    if (!value) return undefined;
+    const range = new vscode.Range(position.translate(0, -value.typed.length), position);
+    return this.catalog().map((brand) => {
+      const item = new vscode.CompletionItem({ label: brand.id, description: brand.title }, vscode.CompletionItemKind.Value);
+      item.detail = `${brand.title} · ${brand.category}`;
+      if (brand.aliases.length) item.documentation = `Also matches: ${brand.aliases.join(', ')}`;
+      // Typing an alias or the product name finds the brand too.
+      item.filterText = [brand.id, ...brand.aliases, brand.title].join(' ');
+      item.range = range;
+      return item;
+    });
+  }
+}

src/brands.ts

@@ -0,0 +1,33 @@
+import fs from 'node:fs';
+
+export interface Brand {
+  id: string;
+  title: string;
+  category: string;
+  aliases: string[];
+}
+
+/** Archify's built-in brand marks, read from brand-marks/catalog.json. */
+export function loadBrandCatalog(file: string): Brand[] {
+  const catalog = JSON.parse(fs.readFileSync(file, 'utf8')) as { marks?: Partial<Brand>[] };
+  return (catalog.marks ?? [])
+    .filter((mark): mark is Partial<Brand> & { id: string } => typeof mark.id === 'string')
+    .map((mark) => ({ id: mark.id, title: mark.title ?? mark.id, category: mark.category ?? '', aliases: mark.aliases ?? [] }));
+}
+
+export interface BrandValue {
+  /** What has been typed of the value so far. */
+  typed: string;
+}
+
+/**
+ * Whether the text before the cursor ends inside a `brand` value:
+ * `brand: post` or `{ id: db, brand: "post` in YAML, `"brand": "post` in JSON.
+ */
+export function brandValueAt(linePrefix: string, format: 'yaml' | 'json'): BrandValue | undefined {
+  const match =
+    format === 'yaml'
+      ? /(?:^|[\s{,])brand:\s*["']?([\w.-]*)$/.exec(linePrefix)
+      : /"brand"\s*:\s*"([\w.-]*)$/.exec(linePrefix);
+  return match ? { typed: match[1] } : undefined;
+}

src/diagnostics.ts

@@ -1,7 +1,7 @@
 import { parse, ParseError } from 'jsonc-parser';
 import * as vscode from 'vscode';
 import { isArchifyFile, readDiagramSource } from './detect';
-import { rangeForPointer, rangeForPointerYaml, yamlSyntaxProblems } from './jsonPointer';
+import { diagnosticPointer, rangeForPointer, rangeForPointerYaml, yamlSyntaxProblems } from './jsonPointer';
 import { ArchifyDiagnostic, isEvidenceError, validate } from './renderer';
 import { evidenceMode, log, runtimeFor } from './runtime';
 
@@ -133,7 +133,8 @@ export class DiagnosticsController implements vscode.Disposable {
       this.collection.set(
         doc.uri,
         result.diagnostics.map((item) => {
-          const offsets = source.format === 'yaml' ? rangeForPointerYaml(text, item.subject?.path) : rangeForPointer(text, item.subject?.path);
+          const pointer = diagnosticPointer(item);
+          const offsets = source.format === 'yaml' ? rangeForPointerYaml(text, pointer) : rangeForPointer(text, pointer);
           const range = new vscode.Range(doc.positionAt(offsets.start), doc.positionAt(offsets.end));
           const fix = item.supportedFixes?.[0];
           const diagnostic = new vscode.Diagnostic(

src/extension.ts

@@ -1,6 +1,7 @@
 import fs from 'node:fs/promises';
 import path from 'node:path';
 import * as vscode from 'vscode';
+import { BRAND_COMPLETION_SELECTOR, BrandCompletionProvider } from './brandCompletion';
 import { diagramBaseName, isArchifyFile, isArchifyHtml, isDiagramFileName, readDiagramSource } from './detect';
 import { DiagnosticsController } from './diagnostics';
 import { HTML_VIEW_TYPE, HtmlViewerProvider } from './htmlViewer';
@@ -18,7 +19,13 @@ function isHtmlUri(uri: vscode.Uri): boolean {
 export function activate(context: vscode.ExtensionContext): void {
   const previews = new PreviewManager(context);
   const htmlViewer = new HtmlViewerProvider();
-  context.subscriptions.push(previews, htmlViewer, new DiagnosticsController(context), log());
+  context.subscriptions.push(
+    previews,
+    htmlViewer,
+    new DiagnosticsController(context),
+    log(),
+    vscode.languages.registerCompletionItemProvider(BRAND_COMPLETION_SELECTOR, new BrandCompletionProvider(context.extensionPath), ' ', '"'),
+  );
 
   /** The file a command applies to: explicit argument, focused preview or viewer, then the text editor. */
   function targetUri(arg?: unknown): vscode.Uri | undefined {

src/jsonPointer.ts

@@ -6,6 +6,14 @@ export interface OffsetRange {
   end: number;
 }
 
+/**
+ * The JSON pointer an Archify diagnostic is about. Most diagnostics carry it
+ * in subject.path; brand diagnostics only start their message with it.
+ */
+export function diagnosticPointer(diagnostic: { message: string; subject?: { path?: string } }): string | undefined {
+  return diagnostic.subject?.path ?? /^(\/[^\s"]+)\s/.exec(diagnostic.message)?.[1];
+}
+
 /** Splits an RFC 6901 JSON pointer into path segments. */
 export function pointerSegments(pointer: string): (string | number)[] {
   if (!pointer || pointer === '/') return [];

test/brands.test.ts

@@ -0,0 +1,44 @@
+import assert from 'node:assert/strict';
+import path from 'node:path';
+import { test } from 'node:test';
+import { brandValueAt, loadBrandCatalog } from '../src/brands';
+import { diagnosticPointer } from '../src/jsonPointer';
+
+const root = path.resolve(__dirname, '..', '..');
+const catalogFile = path.join(root, 'vendor', 'archify', 'brand-marks', 'catalog.json');
+
+test('loads the bundled brand catalog', () => {
+  const brands = loadBrandCatalog(catalogFile);
+  assert.ok(brands.length >= 100, `${brands.length} brands`);
+  const postgres = brands.find((brand) => brand.id === 'postgresql');
+  assert.ok(postgres);
+  assert.ok(postgres.aliases.includes('postgres'));
+  assert.ok(brands.every((brand) => brand.id && brand.title));
+});
+
+test('finds a brand value being typed in YAML', () => {
+  assert.deepEqual(brandValueAt('    brand: ', 'yaml'), { typed: '' });
+  assert.deepEqual(brandValueAt('    brand: post', 'yaml'), { typed: 'post' });
+  assert.deepEqual(brandValueAt('  - brand: apache-ka', 'yaml'), { typed: 'apache-ka' });
+  assert.deepEqual(brandValueAt('    brand: "red', 'yaml'), { typed: 'red' });
+  assert.deepEqual(brandValueAt('  - { id: db, brand: post', 'yaml'), { typed: 'post' });
+  assert.equal(brandValueAt('    label: post', 'yaml'), undefined);
+  assert.equal(brandValueAt('    subbrand: post', 'yaml'), undefined);
+  assert.equal(brandValueAt('    brand: postgresql ', 'yaml'), undefined, 'value already finished');
+});
+
+test('finds a brand value being typed in JSON', () => {
+  assert.deepEqual(brandValueAt('      "brand": "', 'json'), { typed: '' });
+  assert.deepEqual(brandValueAt('{ "id": "db", "brand": "post', 'json'), { typed: 'post' });
+  assert.equal(brandValueAt('      "brand": ', 'json'), undefined, 'not inside the string yet');
+  assert.equal(brandValueAt('      "label": "post', 'json'), undefined);
+});
+
+test('diagnostic pointer comes from subject.path, else from a leading pointer in the message', () => {
+  assert.equal(diagnosticPointer({ message: 'x', subject: { path: '/components/0' } }), '/components/0');
+  assert.equal(
+    diagnosticPointer({ message: '/components/0/brand "aws" is not a built-in brand; closest IDs: airtable' }),
+    '/components/0/brand',
+  );
+  assert.equal(diagnosticPointer({ message: 'Label "x" is wider than node' }), undefined);
+});

test/integration/suite.ts

@@ -131,6 +131,54 @@ export async function run(): Promise<void> {
     );
   });
 
+  await check('suggests brand IDs after brand: in .archify files', async () => {
+    const target = workspaceFile('brands.archify');
+    const text = [
+      'schema_version: 1',
+      'diagram_type: architecture',
+      'meta:',
+      '  title: Brands',
+      'components:',
+      '  - id: db',
+      '    type: database',
+      '    label: DB',
+      '    brand: ',
+      '  - id: bus',
+      '    type: messagebus',
+      '    label: Bus',
+      '    brand: kafka',
+      '',
+    ].join('\n');
+    await vscode.workspace.fs.writeFile(target, new TextEncoder().encode(text));
+    const doc = await vscode.workspace.openTextDocument(target);
+    const labels = async (line: number) => {
+      const list = await vscode.commands.executeCommand<vscode.CompletionList>(
+        'vscode.executeCompletionItemProvider',
+        doc.uri,
+        new vscode.Position(line, doc.lineAt(line).text.length),
+      );
+      return list.items.map((item) => (typeof item.label === 'string' ? item.label : item.label.label));
+    };
+    const empty = await labels(8);
+    assert.ok(empty.includes('postgresql') && empty.includes('redis'), 'brand IDs offered after "brand: "');
+    const kafka = await labels(12);
+    assert.ok(kafka.includes('apache-kafka'), 'the alias "kafka" finds apache-kafka');
+    assert.equal((await labels(7)).includes('postgresql'), false, 'nothing offered for other fields');
+  });
+
+  await check('an unknown brand is reported on its own line', async () => {
+    const target = workspaceFile('unknown-brand.archify');
+    const text = new TextDecoder().decode(await vscode.workspace.fs.readFile(workspaceFile('web-platform.archify')))
+      .replace(/^( {2}- id: [^\n]+\n)/m, '$1    brand: not-a-brand\n');
+    await vscode.workspace.fs.writeFile(target, new TextEncoder().encode(text));
+    const doc = await vscode.workspace.openTextDocument(target);
+    await vscode.window.showTextDocument(doc);
+    const diagnostic = await waitFor('brand/unknown diagnostic', () =>
+      vscode.languages.getDiagnostics(doc.uri).find((d) => d.source === 'archify' && d.code === 'brand/unknown'),
+    );
+    assert.match(doc.lineAt(diagnostic.range.start.line).text, /brand: not-a-brand/);
+  });
+
   await check('opens a live preview beside the source', async () => {
     await vscode.commands.executeCommand('archify.showPreviewToSide', workspaceFile('production-deployment.architecture.json'));
     const tabs = await waitFor('preview tab', () => {