import * as assert from "node:assert";
import * as vscode from "vscode";
import { activateApi, settle } from "./helpers";

async function api() {
  const ext = vscode.extensions.getExtension("benstull.vscode-cowriting-plugin")!;
  return (await ext.activate()) as import("../../../src/extension").CowritingApi;
}

suite("coediting registry (PUC-7)", () => {
  test("enter → isCoediting true; exit → false; persists in list()", async () => {
    const { coeditingRegistry } = await api();
    const doc = await vscode.workspace.openTextDocument({ language: "markdown", content: "# t\n\nbody\n" });
    await vscode.window.showTextDocument(doc);
    await vscode.commands.executeCommand("cowriting.coeditDocument");
    assert.strictEqual(coeditingRegistry.isCoediting(doc.uri), true);
    assert.ok(coeditingRegistry.list().includes(doc.uri.toString()));
    await vscode.commands.executeCommand("cowriting.stopCoediting");
    assert.strictEqual(coeditingRegistry.isCoediting(doc.uri), false);
  });

  // Task 3 (INV-10): a document that was never entered into coediting gets no
  // native-diff surface at all. QuickDiff's `provideOriginalResource` isn't
  // directly queryable from a host-E2E test, so this asserts the gate INPUTS
  // structurally: `isCoediting` stays false and the SCM change count — which
  // `ScmSurfaceController` only ever populates for a coediting doc — stays 0.
  test("non-entered doc: no coediting, no change count (structural, INV-10)", async () => {
    const api = await activateApi();
    const doc = await vscode.workspace.openTextDocument({ language: "markdown", content: "untouched\n" });
    await vscode.window.showTextDocument(doc);
    await settle();
    assert.strictEqual(api.coeditingRegistry.isCoediting(doc.uri), false);
    assert.strictEqual(api.scmSurfaceController.changeCount(doc.uri.toString()), 0);
  });

  // Task 4 (INV-10, PUC-7): the no-hijack scenario — a non-entered doc gets no
  // thread-creation surface at all; entering unlocks it; exiting hides the
  // rendered thread (not the sidecar-backed data); re-entering restores it.
  test("non-entered doc gets no surfaces; exit detaches; re-enter restores threads", async () => {
    const api = await activateApi();
    const doc = await vscode.workspace.openTextDocument({ language: "markdown", content: "# a\n\npara\n" });
    const ed = await vscode.window.showTextDocument(doc);
    // not entered → no thread creation
    ed.selection = new vscode.Selection(2, 0, 2, 4);
    const before = await api.threadController.createThreadOnSelection("hi");
    assert.strictEqual(before, undefined);
    // entered → works
    await vscode.commands.executeCommand("cowriting.coeditDocument");
    const id = await api.threadController.createThreadOnSelection("hi");
    assert.ok(id);
    // exit → rendered thread set empty; re-enter → restored from sidecar
    await vscode.commands.executeCommand("cowriting.stopCoediting");
    assert.strictEqual(api.threadController.getRendered(api.proposalController.keyFor(doc)).length, 0);
    await vscode.commands.executeCommand("cowriting.coeditDocument");
    await settle();
    assert.strictEqual(api.threadController.getRendered(api.proposalController.keyFor(doc)).length, 1);
  });
});