import { describe, expect, it } from "vitest";

import { decodeSyncMessage, encodeSyncMessage, isSyncMessage } from "./sync-wire";
import type { SyncMessage } from "./sync-types";

describe("sync wire codec", () => {
  it("round-trips sync messages through base64url JSON", () => {
    const message: SyncMessage = {
      type: "SYNC_HELLO",
      deviceId: "phone-\u2603",
      clockMs: 1_778_000_000_000,
      vaultVersion: 4,
    };

    const encoded = encodeSyncMessage(message);

    expect(encoded).toMatch(/^[A-Za-z0-9_-]+$/);
    expect(encoded).not.toMatch(/[+/=]/);
    expect(decodeSyncMessage(encoded)).toEqual(message);
  });

  it("round-trips manifest and encrypted entry payloads", () => {
    const messages: SyncMessage[] = [
      {
        type: "SYNC_MANIFEST",
        entries: [{ id: "entry-1", modifiedAt: 42, deletedAt: 45, hash: "abc123" }],
      },
      {
        type: "SYNC_ENTRIES",
        entries: [
          {
            id: "entry-1",
            modifiedAt: 42,
            ciphertext: "ciphertext",
            nonce: "nonce",
            tag: "tag",
          },
        ],
      },
    ];

    for (const message of messages) {
      expect(decodeSyncMessage(encodeSyncMessage(message))).toEqual(message);
    }
  });

  it("validates message-specific required fields", () => {
    expect(isSyncMessage({ type: "SYNC_REQUEST", ids: ["a", "b"] })).toBe(true);
    expect(isSyncMessage({ type: "PAIR_ACCEPT", edPublicKey: "key", name: "Laptop" })).toBe(
      true
    );
    expect(isSyncMessage({ type: "SYNC_REQUEST", ids: [7] })).toBe(false);
    expect(isSyncMessage({ type: "SYNC_HELLO", deviceId: "phone", clockMs: "now" })).toBe(
      false
    );
    expect(isSyncMessage({ type: "SYNC_MANIFEST", entries: [{ id: "a" }] })).toBe(false);
    expect(isSyncMessage({ type: "UNKNOWN" })).toBe(false);
  });

  it("rejects malformed wire payloads with a stable error", () => {
    const malformedJson = btoa("{").replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/g, "");
    const unknownType = btoa(JSON.stringify({ type: "BOGUS" }))
      .replace(/\+/g, "-")
      .replace(/\//g, "_")
      .replace(/=+$/g, "");

    expect(() => decodeSyncMessage("@@@")).toThrow("invalid sync message");
    expect(() => decodeSyncMessage("A")).toThrow("invalid sync message");
    expect(() => decodeSyncMessage(malformedJson)).toThrow("invalid sync message");
    expect(() => decodeSyncMessage(unknownType)).toThrow("invalid sync message");
  });
});