/**
 * The camo editor says things in two places, and the way it goes wrong is
 * always the same: something that is not a pattern writes to the line under
 * the Pattern label. Signing in used to put "Picked up where you left off,
 * saving to @you" there, above a grid of patterns it was not describing.
 *
 * The other half of the same rule is Save. With no account there is nothing to
 * save to, and a sentence saying so under the pattern grid is not what a
 * player who just pressed Save is looking at; the sign-in dialog is.
 *
 * Both checks are structural. There is nothing to catch at runtime: the wrong
 * line is still a line, it renders, and nothing errors.
 *
 * Run with `npm test`.
 */
import { test } from "node:test";
import assert from "node:assert/strict";
import { readFile } from "node:fs/promises";
import { join } from "node:path";
import { fileURLToPath } from "node:url";

const web = fileURLToPath(new URL("../", import.meta.url));
const source = await readFile(join(web, "src/camo/editor.ts"), "utf8");

/** The body of a top-level function in the editor, by its declaration. */
function body(declaration) {
  const start = source.indexOf(declaration);
  assert.notEqual(start, -1, `${declaration} moved or was renamed`);
  // Every nested block in this file closes at four spaces or deeper, so the
  // first two-space brace is the function's own.
  const end = source.indexOf("\n  }", start);
  assert.notEqual(end, -1, `${declaration} has no end`);
  return { start, end, text: source.slice(start, end) };
}

test("only the pattern picker writes the pattern hint", () => {
  const writes = [...source.matchAll(/patternHint\.textContent\s*=/g)];
  assert.equal(
    writes.length,
    1,
    "the pattern hint has more than one writer; a save, a sign-in or an " +
      "import would leave it describing something else",
  );
  const marker = body("function markPattern(): void {");
  const at = writes[0].index;
  assert.ok(
    at > marker.start && at < marker.end,
    "the pattern hint is written from outside markPattern",
  );
});

test("save with no account opens the sign-in dialog", () => {
  const save = body("function doSave(");
  assert.match(
    save.text,
    /if \(!repoSession\) \{[^}]*collection\.signIn\(\)/,
    "saving without an account should put the sign-in dialog up, not a message",
  );
});