/* Signing in through an identity provider.
 *
 * The provider is real enough to be worth testing against: it signs a real
 * RS256 token with a key InkNote fetches and checks (e2e/fakeIdp.mjs). So the
 * claims under test are not "a button exists" but:
 *
 *   • the whole redirect journey ends in a signed-in app, with an account that
 *     did not exist before — and never an administrator;
 *   • the same person coming back a second time is the same account, and an
 *     account that already existed under that name is linked rather than
 *     duplicated;
 *   • the token in the URL is a one-time ticket, not the session token, and the
 *     address is cleaned behind it;
 *   • a refusal at the provider, a token signed with the wrong key and a token
 *     addressed to somebody else all end at the sign-in screen, signed out.
 *
 * The last group is the point of the exercise. A sign-in that only works is not
 * evidence of anything.
 */
import { BASE, api, check, launch, newPage, report } from "./lib.mjs";
import { startFakeIdp } from "./fakeIdp.mjs";

const ISSUER = "http://idp.test:3011";
const ADMIN = {
  user: process.env.INKNOTE_ADMIN || "marc",
  pass: process.env.INKNOTE_ADMIN_PASS || "geheim123",
};

const unique = Math.floor(Math.random() * 1e6);
const idp = await startFakeIdp({
  port: 3011,
  issuer: ISSUER,
  clientId: "inknote-test",
  clientSecret: "test-secret",
});

const browser = await launch();
let adminPage;
const madeUsers = [];
try {
  /* An administrator, to look at the accounts this creates and to clean up. */
  adminPage = await newPage(browser);
  await adminPage.goto(BASE, { waitUntil: "networkidle" });
  await adminPage.getByPlaceholder("Username").fill(ADMIN.user);
  await adminPage.getByPlaceholder("Password").fill(ADMIN.pass);
  await adminPage.getByRole("button", { name: "Sign In" }).click();
  await adminPage.waitForSelector("text=Dashboard", { timeout: 20000 });

  const accounts = async () => (await api(adminPage, "GET", "/admin/users")).body;
  const accountNamed = async (name) => (await accounts()).find((u) => u.username === name);

  /* ── the offer ── */
  const page = await newPage(browser);
  const seen = [];
  page.on("framenavigated", (f) => f === page.mainFrame() && seen.push(f.url()));
  await page.goto(BASE, { waitUntil: "networkidle" });
  await page.waitForTimeout(800);

  const methods = await page.evaluate(async () => (await fetch("/api/auth/methods")).json());
  check(methods?.oidc?.enabled === true, "the server says there is a second way in", JSON.stringify(methods));
  check(
    !JSON.stringify(methods).includes("secret") && !JSON.stringify(methods).includes("client"),
    "and says nothing else about it to a stranger",
    JSON.stringify(methods)
  );
  check((await page.locator("[data-oidc-signin]").count()) === 1, "the sign-in screen offers it");
  check(
    (await page.locator("[data-oidc-signin]").innerText()).includes("Test IdP"),
    "under the name it was given",
    await page.locator("[data-oidc-signin]").innerText()
  );
  check((await page.getByPlaceholder("Password").count()) === 1, "and the password form is still there");

  /* ── someone the app has never seen ── */
  const newcomer = `sso-newcomer-${unique}`;
  await idp.setNext({
    identity: { sub: `subject-new-${unique}`, preferred_username: newcomer, name: "A Newcomer" },
  });

  await page.locator("[data-oidc-signin]").click();
  await page.waitForLoadState("networkidle");
  check(page.url().startsWith(`${ISSUER}/authorize`), "pressing it leads to the provider", page.url());
  const authorizeUrl = new URL(page.url());
  check(
    authorizeUrl.searchParams.get("code_challenge_method") === "S256" &&
      !!authorizeUrl.searchParams.get("state") &&
      !!authorizeUrl.searchParams.get("nonce"),
    "with PKCE, a state and a nonce",
    authorizeUrl.search.slice(0, 120)
  );

  await page.locator("[data-idp-approve]").click();
  await page.waitForSelector("text=Dashboard", { timeout: 20000 });
  await page.waitForTimeout(1500);
  check(true, "approving there signs in here");

  const created = await accountNamed(newcomer);
  madeUsers.push(created?.id);
  check(!!created, "an account was made for them", newcomer);
  check(created?.isAdmin === false, "and it is not an administrator");
  check(created?.signsInWithProvider === true, "and has no password of its own");
  check(created?.linkedToProvider === true, "and is marked as belonging to the provider");

  /* ── what the two people involved see ──
   * The one signing in: no password tab, because there is no password behind
   * it. The administrator: which accounts these are, without asking anybody. */
  await page.getByTitle("Account").click();
  await page.waitForTimeout(900);
  const tabs = await page.locator("button").allInnerTexts();
  check(
    !(await page.getByRole("button", { name: "Password", exact: true }).count()),
    "the account panel offers no password to change",
    tabs.join(" | ").slice(0, 120)
  );
  check(
    (await page.locator("[data-account-sso]").count()) === 1,
    "and says which provider it signs in through instead"
  );
  check(
    (await page.locator("[data-account-sso]").innerText()).includes("Test IdP"),
    "by name",
    await page.locator("[data-account-sso]").innerText()
  );

  /* The picture the provider has of them. It is fetched from *this* server with
     a bearer token — an `<img src>` cannot carry one, so the bytes come through
     the API and become an object URL. Which is also why "it is on the page" is
     not enough: ask the browser whether it actually decoded. */
  const drawn = await page.locator("[data-avatar]").first().evaluate((img) => ({
    src: img.currentSrc || img.src,
    width: img.naturalWidth,
  }));
  /* The provider keeps this one out of the token and behind its own door, which
     is what a lean provider does — so this passing means both the second
     question to /userinfo and the token sent with the picture request. */
  check(drawn.width > 0, "the profile picture from the provider is drawn", JSON.stringify(drawn));
  check(
    drawn.src.startsWith("blob:"),
    "from bytes this server handed over, not from the provider's address",
    drawn.src.slice(0, 40)
  );
  await page.keyboard.press("Escape");
  await page.waitForTimeout(500);

  await adminPage.getByTitle("Account").click();
  await adminPage.waitForTimeout(700);
  await adminPage.getByRole("button", { name: "Administration" }).click();
  await adminPage.waitForTimeout(1500);
  const ssoRow = adminPage.locator(`text=${newcomer}`).locator("xpath=ancestor::div[1]");
  check(
    (await adminPage.locator("[data-user-sso]").count()) >= 1,
    "the administrator sees which accounts come from the provider",
    `${await adminPage.locator("[data-user-sso]").count()} marked`
  );
  check(
    (await ssoRow.innerText()).includes("SSO"),
    "on the row of the account itself",
    (await ssoRow.innerText()).replace(/\n/g, " ").slice(0, 100)
  );
  check(
    (await adminPage.locator("body").innerText()).includes("Give a password"),
    "and is offered to give it a password rather than to reset one"
  );
  check(
    (await adminPage.locator(`[data-avatar="${created.id}"]`).count()) === 1,
    "and sees their picture beside the name"
  );
  await adminPage.keyboard.press("Escape");
  await adminPage.waitForTimeout(400);
  await adminPage.keyboard.press("Escape");
  await adminPage.waitForTimeout(600);

  /* The address is cleaned, and what was in it was a ticket, not the token. */
  const returned = seen.find((u) => u.includes("oidc="));
  check(!!returned, "the provider sent the browser home with something in the URL");
  check(
    !!returned && !returned.includes(await page.evaluate(() => localStorage.getItem("inknote_token"))),
    "which was not the session token"
  );
  check(!page.url().includes("oidc"), "and the address was cleaned afterwards", page.url());

  /* A session lives in two places — IndexedDB and localStorage — so "signed out
     again" means a browser that never saw this one. Every case below gets one. */
  const signedOutBrowser = () => newPage(browser);

  /* ── the ticket is single use ── */
  const replay = await signedOutBrowser();
  await replay.goto(returned, { waitUntil: "networkidle" });
  await replay.waitForTimeout(2000);
  check(
    (await replay.getByPlaceholder("Password").count()) === 1,
    "the same ticket a second time is worth nothing",
    replay.url()
  );
  await replay.context().close();

  /* ── the same person again is the same account ── */
  const again = await signedOutBrowser();
  await again.goto(BASE, { waitUntil: "networkidle" });
  await again.locator("[data-oidc-signin]").click();
  await again.waitForLoadState("networkidle");
  await again.locator("[data-idp-approve]").click();
  await again.waitForSelector("text=Dashboard", { timeout: 20000 });
  await again.waitForTimeout(1200);
  const afterSecond = (await accounts()).filter((u) => u.username.startsWith(`sso-newcomer-${unique}`));
  check(afterSecond.length === 1, "signing in again does not make a second account", `${afterSecond.length}`);
  await again.context().close();

  /* ── an account that already existed here ── */
  const existing = `sso-existing-${unique}`;
  const madeByAdmin = await api(adminPage, "POST", "/admin/users", {
    username: existing,
    password: "e2epass123",
    displayName: "Already Here",
  });
  madeUsers.push(madeByAdmin.body?.id);
  check(madeByAdmin.status === 201, "an ordinary account exists under that name");

  await idp.setNext({
    identity: { sub: `subject-existing-${unique}`, preferred_username: existing, name: "Already Here" },
  });
  const second = await signedOutBrowser();
  await second.goto(BASE, { waitUntil: "networkidle" });
  await second.locator("[data-oidc-signin]").click();
  await second.waitForLoadState("networkidle");
  await second.locator("[data-idp-approve]").click();
  await second.waitForSelector("text=Dashboard", { timeout: 20000 });
  await second.waitForTimeout(1200);

  /* An account that had a password and was then linked: it keeps the password,
     and still manages it nowhere but through an administrator. */
  await second.getByTitle("Account").click();
  await second.waitForTimeout(900);
  check(
    !(await second.getByRole("button", { name: "Password", exact: true }).count()),
    "an account linked to the provider is offered no password tab either"
  );
  check(
    (await second.locator("[data-account-sso]").innerText()).includes("administrator"),
    "and is told who changes the one it has",
    await second.locator("[data-account-sso]").innerText()
  );
  await second.keyboard.press("Escape");
  await second.waitForTimeout(400);

  const linked = (await accounts()).filter((u) => u.username === existing);
  check(linked.length === 1, "the identity is linked to it rather than duplicated", `${linked.length}`);
  check(
    linked[0]?.signsInWithProvider === false,
    "and it keeps the password it already had — one way in does not close the other"
  );
  check(
    linked[0]?.linkedToProvider === true,
    "while still being shown as one that can use the provider"
  );
  await second.context().close();

  /* ── the ways it must fail ── */
  const signedOut = async (page) => (await page.getByPlaceholder("Password").count()) === 1;

  const denied = await signedOutBrowser();
  await denied.goto(BASE, { waitUntil: "networkidle" });
  await denied.locator("[data-oidc-signin]").click();
  await denied.waitForLoadState("networkidle");
  await denied.locator("[data-idp-deny]").click();
  await denied.waitForTimeout(2000);
  check(await signedOut(denied), "a refusal at the provider ends signed out");
  check(
    (await denied.locator("body").innerText()).includes("did not allow"),
    "and says so on the sign-in screen",
    (await denied.locator("body").innerText()).slice(0, 120)
  );
  await denied.context().close();

  const refusedBy = async (label, misbehave) => {
    await idp.setNext({
      identity: { sub: `subject-forged-${unique}`, preferred_username: `sso-forged-${unique}`, name: "Forged" },
      misbehave,
    });
    const forged = await signedOutBrowser();
    await forged.goto(BASE, { waitUntil: "networkidle" });
    await forged.locator("[data-oidc-signin]").click();
    await forged.waitForLoadState("networkidle");
    await forged.locator("[data-idp-approve]").click();
    await forged.waitForTimeout(2000);
    check(await signedOut(forged), label);
    check(
      !(await accounts()).some((u) => u.username === `sso-forged-${unique}`),
      `${label} — and no account was made from it`
    );
    await forged.context().close();
  };
  await refusedBy("a token signed with a key the provider does not publish is refused", { wrongKey: true });
  await refusedBy("a token addressed to another client is refused", { wrongAudience: true });

  /* ── an account made this way has no password ── */
  const tryPassword = await adminPage.evaluate(async (name) => {
    const r = await fetch("/api/auth/login", {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ username: name, password: "" }),
    });
    return r.status;
  }, newcomer);
  check(tryPassword === 401, "and cannot be signed into with a password", `${tryPassword}`);
} catch (e) {
  check(false, "suite ran to the end", e.stack || e.message);
} finally {
  /* Tidy up whatever the run made, including the accounts the provider caused. */
  try {
    for (const id of madeUsers.filter(Boolean)) await api(adminPage, "DELETE", `/admin/users/${id}`);
    await adminPage?.context().close();
  } catch {
    /* the report matters more than the cleanup */
  }
  await browser.close();
  await idp.stop();
  process.exit(report());
}