import assert from 'node:assert/strict';
import path from 'node:path';
import * as vscode from 'vscode';

const EXTENSION_ID = 'vscode-extensions.archify-vscode-ext';

function workspaceFile(name: string): vscode.Uri {
  const folder = vscode.workspace.workspaceFolders?.[0];
  assert.ok(folder, 'a workspace folder is open');
  return vscode.Uri.joinPath(folder.uri, name);
}

async function waitFor<T>(what: string, probe: () => T | undefined | false, timeoutMs = 20_000): Promise<T> {
  const start = Date.now();
  for (;;) {
    const value = probe();
    if (value) return value;
    if (Date.now() - start > timeoutMs) throw new Error(`Timed out waiting for ${what}`);
    await new Promise((resolve) => setTimeout(resolve, 200));
  }
}

function webviewTabs(viewTypeSuffix: string): vscode.Tab[] {
  return vscode.window.tabGroups.all
    .flatMap((group) => group.tabs)
    .filter((tab) =>
      (tab.input instanceof vscode.TabInputWebview && tab.input.viewType.endsWith(viewTypeSuffix)) ||
      (tab.input instanceof vscode.TabInputCustom && tab.input.viewType === viewTypeSuffix));
}

async function check(name: string, body: () => Promise<void>): Promise<void> {
  try {
    await body();
    console.log(`  ✔ ${name}`);
  } catch (error) {
    console.log(`  ✖ ${name}`);
    throw error;
  }
}

export async function run(): Promise<void> {
  console.log('Archify extension integration suite');

  await check('activates on a diagram source and sets the context key', async () => {
    const doc = await vscode.workspace.openTextDocument(workspaceFile('production-deployment.architecture.json'));
    await vscode.window.showTextDocument(doc);
    const extension = vscode.extensions.getExtension(EXTENSION_ID);
    assert.ok(extension, 'extension is installed');
    await waitFor('activation', () => extension.isActive);
  });

  await check('opens a live preview beside the source', async () => {
    await vscode.commands.executeCommand('archify.showPreviewToSide');
    const tabs = await waitFor('preview tab', () => {
      const found = webviewTabs('archify.preview');
      return found.length > 0 && found;
    });
    assert.equal(tabs.length, 1);
    assert.match(tabs[0].label, /Preview production-deployment\.architecture\.json/);
  });

  await check('reports validation problems in the Problems panel with JSON ranges', async () => {
    const doc = await vscode.workspace.openTextDocument({
      language: 'json',
      content: JSON.stringify({ schema_version: 1, diagram_type: 'architecture', meta: { title: 'x' }, components: [{ id: 'a' }] }, null, 2),
    });
    await vscode.window.showTextDocument(doc);
    const diagnostics = await waitFor('archify diagnostics', () => {
      const found = vscode.languages.getDiagnostics(doc.uri).filter((d) => d.source === 'archify');
      return found.length > 0 && found;
    });
    const component = diagnostics.find((d) => /components\/0/.test(d.message));
    assert.ok(component, 'a diagnostic for /components/0');
    assert.equal(doc.getText(component.range), '{', 'range points at the component object');
    assert.equal(component.severity, vscode.DiagnosticSeverity.Error);
  });

  await check('clears problems once the document is fixed', async () => {
    const good = await vscode.workspace.openTextDocument(workspaceFile('event-stream.dataflow.json'));
    const doc = await vscode.workspace.openTextDocument({ language: 'json', content: good.getText() });
    await vscode.window.showTextDocument(doc);
    await new Promise((resolve) => setTimeout(resolve, 3000));
    const errors = vscode.languages.getDiagnostics(doc.uri).filter((d) => d.source === 'archify' && d.severity === vscode.DiagnosticSeverity.Error);
    assert.deepEqual(errors.map((d) => d.message), []);
  });

  await check('renders to an HTML file and opens it in the Archify viewer', async () => {
    const source = workspaceFile('cache-miss-request.sequence.json');
    const output = vscode.Uri.file(path.join(path.dirname(source.fsPath), 'cache-miss-request.sequence.html'));
    // Stub the save dialog and the follow-up notification.
    const window = vscode.window as unknown as Record<string, unknown>;
    const originalSave = window.showSaveDialog;
    const originalInfo = window.showInformationMessage;
    window.showSaveDialog = async () => output;
    window.showInformationMessage = async () => 'Open in Viewer';
    try {
      await vscode.commands.executeCommand('archify.renderToHtml', source);
    } finally {
      window.showSaveDialog = originalSave;
      window.showInformationMessage = originalInfo;
    }
    const html = new TextDecoder().decode(await vscode.workspace.fs.readFile(output));
    assert.match(html, /<meta name="generator" content="archify/);
    await waitFor('custom editor tab', () => webviewTabs('archify.htmlViewer').length > 0);
  });

  await check('source-backed diagram previews with the evidence fallback', async () => {
    const uri = workspaceFile('mco-runtime.architecture.json');
    await vscode.commands.executeCommand('archify.showPreview', uri);
    await waitFor('second preview tab', () => webviewTabs('archify.preview').length >= 2);
    const doc = await vscode.workspace.openTextDocument(uri);
    const diagnostics = await waitFor('evidence diagnostics', () => {
      const found = vscode.languages.getDiagnostics(doc.uri).filter((d) => d.source === 'archify');
      return found.length > 0 && found;
    });
    assert.ok(
      diagnostics.every((d) => d.severity !== vscode.DiagnosticSeverity.Error),
      'unverifiable evidence is a warning in fallback mode',
    );
  });
}