/**
 * Shared host-E2E helpers (native-surfaces migration, Task 2). NEW suites use
 * these; existing suites keep their own local copies (out of scope to
 * refactor them onto this shared file — see the Task 2 brief).
 */
import * as assert from "node:assert";
import * as vscode from "vscode";
import type { CowritingApi } from "../../../src/extension";
import { renderReview } from "../../../src/trackChangesModel";

/** Activate the extension and return its exported API (asserts it is real). */
export async function activateApi(): Promise<CowritingApi> {
  const ext = vscode.extensions.getExtension("benstull.vscode-cowriting-plugin")!;
  const api = (await ext.activate()) as CowritingApi;
  assert.ok(api?.diffViewController, "extension exports diffViewController");
  return api;
}

/**
 * Task 8: the pure render probe the deleted TrackChangesPreviewController used
 * to wrap (`renderHtmlFor`) — the sunset webview was a thin shell around this
 * exact call (F6 baseline + F3 spans + F4 pending proposals -> `renderReview`).
 * Suites that used to read `controller.renderHtmlFor(key)` now call this
 * directly against the surviving controllers; no webview involved.
 */
export function renderHtmlFor(api: CowritingApi, doc: vscode.TextDocument, key: string): string {
  const baseline = api.diffViewController.getBaseline(key);
  const current = doc.getText();
  return renderReview(
    baseline?.text ?? current,
    current,
    api.attributionController.spansFor(doc),
    api.proposalController.listProposals(doc),
    { pinned: baseline?.reason === "pinned" },
  );
}

/** A short fixed settle, for state that updates synchronously-ish after a command. */
export function settle(): Promise<void> {
  return new Promise((r) => setTimeout(r, 150));
}

/** Poll `predicate` every 100ms until it is true, or fail after `timeoutMs`. */
export async function settleUntil(predicate: () => boolean, timeoutMs = 5000): Promise<void> {
  const start = Date.now();
  while (!predicate()) {
    if (Date.now() - start > timeoutMs) {
      assert.fail(`settleUntil: predicate did not become true within ${timeoutMs}ms`);
    }
    await new Promise((r) => setTimeout(r, 100));
  }
}