// Tests for the signup-first join page's pure decision helpers (prejoin.js).
import test from "node:test";
import assert from "node:assert/strict";
import {
  PREJOIN_STASH_KEY, offerPrejoin, prejoinStash, readPrejoinReturn, homeSigninURL,
  autoEnrolOnClaim,
} from "../web/static/prejoin.js";

const HOME = "https://home.example.com";
const base = { kind: "join", homeOrigin: HOME, embed: false, native: false, signedUp: false };

test("offerPrejoin: fresh join/setup kinds with a home server", () => {
  assert.equal(offerPrejoin(base), true);
  assert.equal(offerPrejoin({ ...base, kind: "setup" }), true);
});

test("offerPrejoin: never for established or unsupported contexts", () => {
  for (const kind of ["device", "adopt", "adopt-admin"]) {
    assert.equal(offerPrejoin({ ...base, kind }), false);
  }
  assert.equal(offerPrejoin({ ...base, homeOrigin: "" }), false);
  assert.equal(offerPrejoin({ ...base, homeOrigin: "__HOME_ORIGIN__" }), false);
  assert.equal(offerPrejoin({ ...base, embed: true }), false);
  assert.equal(offerPrejoin({ ...base, native: true }), false);
  assert.equal(offerPrejoin({ ...base, signedUp: true }), false);
});

// The create-a-space journey: home hands over /join/setup?src=home moments
// after a sign-in there (and having already saved the space to that account).
// Leading with the sign-in door again reads as the flow forgetting.
test("offerPrejoin: a setup link from a signed-in home page never leads with sign-in", () => {
  assert.equal(offerPrejoin({ ...base, kind: "setup", fromHome: true }), false);
  assert.equal(offerPrejoin({ ...base, kind: "join", fromHome: true }), false);
  assert.equal(offerPrejoin({ ...base, kind: "setup", fromHome: false }), true);
});

// One sign-in per space: an arrival that already signed in on the way here
// enrols itself at claim time, so nothing asks again later.
test("autoEnrolOnClaim: the two already-signed-in arrivals, and nobody else", () => {
  const at = { homeOrigin: HOME, embed: false };
  assert.equal(autoEnrolOnClaim({ ...at, signedUp: true }), true);
  assert.equal(autoEnrolOnClaim({ ...at, fromHome: true }), true);
  assert.equal(autoEnrolOnClaim({ ...at }), false, "a cold joiner still meets the ask");
  assert.equal(autoEnrolOnClaim({ ...at, fromHome: true, embed: true }), false);
  assert.equal(autoEnrolOnClaim({ signedUp: true, fromHome: true, homeOrigin: "", embed: false }), false);
  assert.equal(autoEnrolOnClaim({ signedUp: true, homeOrigin: "__HOME_ORIGIN__", embed: false }), false);
});

test("round trip: stash then read back on a genuine return", () => {
  const now = 1_000_000;
  const stored = prejoinStash({ frag: "e1.SECRET~Ann~bkey", nonce: "n0nce", now });
  const r = readPrejoinReturn({ search: "?su=n0nce", storedJSON: stored, now: now + 5000 });
  assert.deepEqual(r, { signedUp: true, frag: "e1.SECRET~Ann~bkey" });
});

test("readPrejoinReturn: no marker, forged nonce, stale stash, clock skew", () => {
  const now = 1_000_000;
  const stored = prejoinStash({ frag: "f", nonce: "good", now });
  assert.deepEqual(readPrejoinReturn({ search: "", storedJSON: stored, now }),
    { signedUp: false, frag: "" });
  assert.deepEqual(readPrejoinReturn({ search: "?su=evil", storedJSON: stored, now }),
    { signedUp: false, frag: "" });
  assert.deepEqual(readPrejoinReturn({ search: "?su=good", storedJSON: stored, now: now + 61 * 60 * 1000 }),
    { signedUp: false, frag: "" });
  assert.deepEqual(readPrejoinReturn({ search: "?su=good", storedJSON: stored, now: now - 1000 }),
    { signedUp: false, frag: "" });
  assert.deepEqual(readPrejoinReturn({ search: "?su=good", storedJSON: "not json", now }),
    { signedUp: false, frag: "" });
  assert.deepEqual(readPrejoinReturn({ search: "?su=good", storedJSON: "", now }),
    { signedUp: false, frag: "" });
});

test("homeSigninURL: return URL rides the fragment, encoded, no invite secret", () => {
  const url = homeSigninURL(HOME, "https://chat.example.com", "/join/abc", "n+once");
  assert.equal(url,
    HOME + "/#joinret=" + encodeURIComponent("https://chat.example.com/join/abc?su=" + encodeURIComponent("n+once")));
  assert.equal(homeSigninURL(HOME + "/", "https://c.example.com", "/join/x", "n"),
    HOME + "/#joinret=" + encodeURIComponent("https://c.example.com/join/x?su=n"));
});

test("stash key is stable", () => assert.equal(PREJOIN_STASH_KEY, "lchat_prejoin"));