import { describe, expect, it } from "vitest";
import {
  importAegisBackup,
  importEncryptedAegisBackup,
  importAndOtpBackup,
  importFreeOtpBackup,
  importTwoFasBackup,
} from "../../src/otp/vendor-backups";
import { scrypt } from "@noble/hashes/scrypt.js";
import {
  bytesToArrayBuffer,
  bytesToHex,
  utf8ToBytes,
} from "../../src/crypto/encoding";

const secret = "JBSWY3DPEHPK3PXP";

async function encryptGcm(
  keyBytes: Uint8Array,
  plaintext: Uint8Array,
  nonce: Uint8Array,
): Promise<{ ciphertext: Uint8Array; tag: Uint8Array }> {
  const key = await crypto.subtle.importKey(
    "raw",
    bytesToArrayBuffer(keyBytes),
    "AES-GCM",
    false,
    ["encrypt"],
  );
  const output = new Uint8Array(
    await crypto.subtle.encrypt(
      { name: "AES-GCM", iv: bytesToArrayBuffer(nonce) },
      key,
      bytesToArrayBuffer(plaintext),
    ),
  );
  return { ciphertext: output.slice(0, -16), tag: output.slice(-16) };
}

function base64(bytes: Uint8Array): string {
  return btoa(String.fromCharCode(...bytes));
}

describe("vendor OTP backup importers", () => {
  it("imports Aegis plaintext entries and skips non-portable token types", () => {
    const result = importAegisBackup(
      JSON.stringify({
        db: {
          entries: [
            {
              type: "totp",
              name: "alice",
              issuer: "Example",
              info: { secret, algo: "SHA1", digits: 6, period: 30 },
            },
            { type: "steam", name: "game", issuer: "Steam", info: { secret } },
          ],
        },
      }),
    );
    expect(result.profiles[0]).toMatchObject({
      issuer: "Example",
      account: "alice",
    });
    expect(result.warnings[0]).toMatch(/steam/iu);
  });

  it("imports 2FAS, andOTP and FreeOTP field layouts", () => {
    expect(
      importTwoFasBackup(
        JSON.stringify({
          services: [
            {
              name: "Example",
              secret,
              otp: {
                account: "alice",
                issuer: "Issuer",
                tokenType: "TOTP",
                algorithm: "SHA1",
                digits: 6,
                period: 30,
              },
            },
          ],
        }),
      ).profiles[0],
    ).toMatchObject({ account: "alice", issuer: "Issuer" });
    expect(
      importAndOtpBackup(
        JSON.stringify([
          {
            secret,
            issuer: "Example",
            label: "bob",
            type: "TOTP",
            algorithm: "SHA1",
            digits: 6,
            period: 30,
          },
        ]),
      ).profiles[0]!.account,
    ).toBe("bob");
    expect(
      importFreeOtpBackup(
        JSON.stringify([
          {
            secret: [49, 50, 51, 52],
            issuerExt: "Example",
            label: "carol",
            type: "totp",
            algo: "SHA1",
            digits: 6,
            period: 30,
          },
        ]),
      ).profiles[0]!.account,
    ).toBe("carol");
  });

  it("refuses encrypted Aegis content instead of guessing", () => {
    expect(() =>
      importAegisBackup(JSON.stringify({ db: "ciphertext", header: {} })),
    ).toThrow(/encrypted/iu);
  });

  it("decrypts authenticated Aegis password vaults locally", async () => {
    const password = "correct horse battery staple";
    const salt = Uint8Array.from({ length: 16 }, (_, index) => index + 1);
    const masterKey = Uint8Array.from(
      { length: 32 },
      (_, index) => 255 - index,
    );
    const wrappingKey = scrypt(password, salt, {
      N: 16,
      r: 8,
      p: 1,
      dkLen: 32,
      maxmem: 1024 * 1024,
    });
    const slotNonce = Uint8Array.from({ length: 12 }, (_, index) => index + 20);
    const dbNonce = Uint8Array.from({ length: 12 }, (_, index) => index + 40);
    const wrapped = await encryptGcm(wrappingKey, masterKey, slotNonce);
    const database = utf8ToBytes(
      JSON.stringify({
        entries: [
          {
            type: "totp",
            name: "alice",
            issuer: "Example",
            info: { secret, algo: "SHA1", digits: 6, period: 30 },
          },
        ],
      }),
    );
    const encrypted = await encryptGcm(masterKey, database, dbNonce);
    const vault = JSON.stringify({
      version: 1,
      header: {
        slots: [
          {
            type: 1,
            n: 16,
            r: 8,
            p: 1,
            salt: bytesToHex(salt),
            key: bytesToHex(wrapped.ciphertext),
            key_params: {
              nonce: bytesToHex(slotNonce),
              tag: bytesToHex(wrapped.tag),
            },
          },
        ],
        params: { nonce: bytesToHex(dbNonce), tag: bytesToHex(encrypted.tag) },
      },
      db: base64(encrypted.ciphertext),
    });
    await expect(
      importEncryptedAegisBackup(vault, password),
    ).resolves.toMatchObject({
      profiles: [
        expect.objectContaining({ account: "alice", issuer: "Example" }),
      ],
    });
    await expect(importEncryptedAegisBackup(vault, "wrong")).rejects.toThrow(
      /incorrect/u,
    );
  });
});