import * as assert from "assert";
import * as fs from "fs";
import * as path from "path";
import * as vscode from "vscode";
import type { CowritingApi } from "../../../src/extension";

const WS = process.env.E2E_WORKSPACE!;
const settle = () => new Promise((r) => setTimeout(r, 400));

async function getApi(): Promise<CowritingApi> {
  const ext = vscode.extensions.getExtension("benstull.vscode-cowriting-plugin")!;
  const api = (await ext.activate()) as CowritingApi;
  assert.ok(api?.trackChangesPreviewController && api?.diffViewController, "exports preview + diffView");
  return api;
}

/** Create + open a fresh markdown doc under WS, returning the doc + its uri key. */
async function freshDoc(rel: string, body: string): Promise<{ doc: vscode.TextDocument; key: string }> {
  const abs = path.join(WS, rel);
  fs.mkdirSync(path.dirname(abs), { recursive: true });
  fs.writeFileSync(abs, body, "utf8");
  const uri = vscode.Uri.file(abs);
  const doc = await vscode.workspace.openTextDocument(uri);
  await vscode.window.showTextDocument(doc);
  await settle();
  return { doc, key: uri.toString() };
}

// F11 host E2E (no LLM): the preview toolbar is the primary interaction surface.
// The webview posts intent messages; the host routes them through the existing
// F4/F6/F3 seams (INV-35). The webview DOM (real button clicks) is sealed and
// manual-smoke only; here we simulate the inbound messages via `receiveMessage`.
suite("F11 preview toolbar (host E2E — message → seam wiring, no LLM)", () => {
  // SLICE-1: the Pin baseline button.
  test("pinBaseline message pins the PREVIEWED doc → marks clear, baseline reason is pinned (PUC-5, INV-35)", async () => {
    const { doc, key } = await freshDoc("docs/f11pin.md", "# F11 pin\n\nA baseline paragraph that will diverge.\n");
    const api = await getApi();
    await vscode.commands.executeCommand("cowriting.showTrackChangesPreview");
    await settle();
    assert.strictEqual(api.trackChangesPreviewController.isOpen(key), true, "panel open");

    // Diverge from the opened baseline so the preview carries a real change-mark.
    const edit = new vscode.WorkspaceEdit();
    edit.insert(doc.uri, doc.positionAt(doc.getText().length), "\n\nA freshly typed paragraph that diverges.\n");
    assert.ok(await vscode.workspace.applyEdit(edit), "operator edit applied");
    await settle();
    const marked = (api.trackChangesPreviewController.getLastModel(key) ?? []).some((o) => o.kind !== "unchanged");
    assert.ok(marked, "the typed paragraph shows as a change before pinning");

    // Simulate the webview's Pin baseline button posting its intent.
    api.trackChangesPreviewController.receiveMessage(key, { type: "pinBaseline" });
    await settle();

    const model = api.trackChangesPreviewController.getLastModel(key) ?? [];
    assert.ok(model.length > 0 && model.every((o) => o.kind === "unchanged"), "after pin, every block is unchanged");
    assert.strictEqual(api.diffViewController.getBaseline(key)?.reason, "pinned", "baseline reason advanced to pinned");
  });

  // SLICE-1 reachability: the orphaned pin command gets a real palette `when`.
  test("pinDiffBaseline is reachable from the command palette (when: editorLangId == markdown)", async () => {
    const pkg = JSON.parse(fs.readFileSync(path.join(__dirname, "../../../../package.json"), "utf8"));
    const entry = (pkg.contributes.menus.commandPalette as Array<{ command: string; when?: string }>).find(
      (m) => m.command === "cowriting.pinDiffBaseline",
    );
    assert.ok(entry, "pinDiffBaseline has a commandPalette entry");
    assert.notStrictEqual(entry!.when, "false", "it is no longer hidden (when:false)");
    assert.match(entry!.when ?? "", /editorLangId == markdown/, "guarded on markdown");
  });
});