/**
 * End-to-end tests for the vault.
 *
 * The client talks to the REAL route handlers through Hono's `fetch`, not to a
 * mock. A mock transport would agree with the client by construction and prove
 * nothing about the wire contract — which is exactly the surface a phone and a
 * daemon have to share.
 */
import { describe, test, expect } from 'bun:test';
import { SubtleCryptoProvider } from '@shade/crypto-web';
import { createVaultRoutes } from '../src/server.js';
import { MemoryVaultStore } from '../src/store.js';
import { HttpVaultTransport } from '../src/http-transport.js';
import { VaultClient, deriveVaultKeys } from '../src/client.js';
import { objectHash } from '../src/crypto.js';

const crypto = new SubtleCryptoProvider();
const AT = 1_786_600_000_000;

function enc(s: string): Uint8Array {
  return new TextEncoder().encode(s);
}
function dec(b: Uint8Array): string {
  return new TextDecoder().decode(b);
}

/** A client wired to a fresh in-memory relay. */
async function harness(masterKey = new Uint8Array(32).fill(7), app = 'scaffold') {
  const store = new MemoryVaultStore();
  const routes = createVaultRoutes(store, crypto);
  const transport = new HttpVaultTransport('http://vault.test', (input, init) =>
    routes.fetch(new Request(input, init)),
  );
  const keys = await deriveVaultKeys(masterKey, app);
  return { store, keys, client: new VaultClient(crypto, keys, transport) };
}

describe('round trip', () => {
  test('files pushed can be pulled back byte-for-byte', async () => {
    const { client } = await harness();
    const files = [
      { path: '.scaffold/plan.md', bytes: enc('# Plan\n\n## Nå\n- [ ] noe\n') },
      { path: '.scaffold/tasks.yaml', bytes: enc('tasks: []\n') },
    ];

    const res = await client.push(files, AT, 'første backup');
    expect(res.seq).toBe(1);
    expect(res.uploaded).toBe(2);

    const { manifest, files: back } = await client.pull();
    expect(manifest.seq).toBe(1);
    expect(manifest.message).toBe('første backup');
    expect(dec(back.get('.scaffold/plan.md')!)).toBe('# Plan\n\n## Nå\n- [ ] noe\n');
    expect(dec(back.get('.scaffold/tasks.yaml')!)).toBe('tasks: []\n');
  });

  test('a fresh device with only the credentials can restore', async () => {
    // The recovery story: same master key, nothing else carried over.
    const master = new Uint8Array(32).fill(11);
    const { client, store } = await harness(master);
    await client.push([{ path: 'notes.yaml', bytes: enc('notes: [en, to]\n') }], AT);

    const routes = createVaultRoutes(store, crypto);
    const transport = new HttpVaultTransport('http://vault.test', (i, init) =>
      routes.fetch(new Request(i, init)),
    );
    const keys = await deriveVaultKeys(master, 'scaffold');
    const fresh = new VaultClient(crypto, keys, transport);

    const { files } = await fresh.pull();
    expect(dec(files.get('notes.yaml')!)).toBe('notes: [en, to]\n');
  });

  test('a different master key cannot read the vault', async () => {
    const { store } = await harness(new Uint8Array(32).fill(1));
    const routes = createVaultRoutes(store, crypto);
    const transport = new HttpVaultTransport('http://vault.test', (i, init) =>
      routes.fetch(new Request(i, init)),
    );
    const wrong = await deriveVaultKeys(new Uint8Array(32).fill(2), 'scaffold');
    const intruder = new VaultClient(crypto, wrong, transport);
    // A different master derives a different vaultId, so there is nothing
    // there to read in the first place — the id is itself a secret.
    await expect(intruder.pull()).rejects.toThrow();
  });
});

describe('versioning', () => {
  test('each push is a new version and old ones stay readable', async () => {
    const { client } = await harness();
    await client.push([{ path: 'plan.md', bytes: enc('versjon 1') }], AT);
    await client.push([{ path: 'plan.md', bytes: enc('versjon 2') }], AT + 1000);
    await client.push([{ path: 'plan.md', bytes: enc('versjon 3') }], AT + 2000);

    const log = await client.history();
    expect(log.head).toBe(3);
    expect(log.entries.map((e) => e.seq)).toEqual([1, 2, 3]);

    // Rollback: the whole point of keeping the log.
    expect(dec((await client.pull(1)).files.get('plan.md')!)).toBe('versjon 1');
    expect(dec((await client.pull(2)).files.get('plan.md')!)).toBe('versjon 2');
    expect(dec((await client.pull()).files.get('plan.md')!)).toBe('versjon 3');
  });

  test('unchanged files are not re-uploaded', async () => {
    // The property that makes backing up a 9 MB workspace on every change
    // affordable: only what actually moved goes over the wire.
    const { client } = await harness();
    const stable = { path: 'stor-logg.md', bytes: enc('x'.repeat(50_000)) };

    const first = await client.push([stable, { path: 'plan.md', bytes: enc('en') }], AT);
    expect(first.uploaded).toBe(2);

    const second = await client.push([stable, { path: 'plan.md', bytes: enc('to') }], AT + 1);
    expect(second.uploaded).toBe(1);
    expect(second.reused).toBe(1);
    expect(second.bytesUploaded).toBeLessThan(1000);

    // And the reused file is still intact in the new version.
    const { files } = await client.pull();
    expect(files.get('stor-logg.md')!.length).toBe(50_000);
  });

  test('a deleted file is absent from the new version but present in the old', async () => {
    const { client } = await harness();
    await client.push(
      [
        { path: 'a.md', bytes: enc('A') },
        { path: 'b.md', bytes: enc('B') },
      ],
      AT,
    );
    await client.push([{ path: 'a.md', bytes: enc('A') }], AT + 1);

    expect((await client.pull()).files.has('b.md')).toBe(false);
    expect(dec((await client.pull(1)).files.get('b.md')!)).toBe('B');
  });
});

describe('the relay is blind', () => {
  test('stored objects contain no plaintext', async () => {
    const { client, store } = await harness();
    await client.push([{ path: 'hemmelig/plan.md', bytes: enc('SENSITIVT INNHOLD') }], AT);

    const log = await store.log(client.vaultId);
    const manifestBytes = await store.getObject(client.vaultId, log[0]!.manifest);
    const asText = dec(manifestBytes!);
    // Neither the contents nor the path leaks: paths live inside the
    // encrypted manifest, not in object names.
    expect(asText).not.toContain('SENSITIVT');
    expect(asText).not.toContain('hemmelig');
  });

  test('object names are the hash of the ciphertext, so the relay can verify', async () => {
    const { client, store } = await harness();
    await client.push([{ path: 'x', bytes: enc('hei') }], AT);
    const log = await store.log(client.vaultId);
    const bytes = await store.getObject(client.vaultId, log[0]!.manifest);
    expect(objectHash(bytes!)).toBe(log[0]!.manifest);
  });

  test('an object whose bytes do not match its name is rejected', async () => {
    const store = new MemoryVaultStore();
    const routes = createVaultRoutes(store, crypto);
    const keys = await deriveVaultKeys(new Uint8Array(32).fill(3), 'scaffold');
    const { signPayload } = await import('@shade/server');
    const { toBase64 } = await import('@shade/core');

    const body = await signPayload(crypto, keys.signingSeed, {
      data: toBase64(enc('juks')),
      publicKey: toBase64(keys.publicKey),
    });
    const res = await routes.fetch(
      new Request(`http://v/v1/vault/${keys.vaultId}/object/${'0'.repeat(64)}`, {
        method: 'PUT',
        headers: { 'content-type': 'application/json' },
        body: JSON.stringify(body),
      }),
    );
    expect(res.status).toBe(400);
    expect((await res.json()).error.code).toBe('BAD_REQUEST');
  });
});

describe('concurrent writers', () => {
  test('a commit from a stale head is refused', async () => {
    // Two devices push from the same version. The second must not be able to
    // overwrite a sequence number that is already history.
    const { client, keys, store } = await harness();
    await client.push([{ path: 'plan.md', bytes: enc('en')}], AT);

    const routes = createVaultRoutes(store, crypto);
    const { signPayload } = await import('@shade/server');
    const { toBase64 } = await import('@shade/core');
    const log = await store.log(keys.vaultId);
    const body = await signPayload(crypto, keys.signingSeed, {
      manifest: log[0]!.manifest,
      seq: 1, // already taken
      at: AT,
      hashes: [],
      publicKey: toBase64(keys.publicKey),
    });

    const res = await routes.fetch(
      new Request(`http://v/v1/vault/${keys.vaultId}/commit`, {
        method: 'POST',
        headers: { 'content-type': 'application/json' },
        body: JSON.stringify(body),
      }),
    );
    expect(res.status).toBe(409);
    const err = await res.json();
    expect(err.error.code).toBe('SEQ_CONFLICT');
    expect(err.head).toBe(1);
  });

  test('a commit referencing a missing object is refused', async () => {
    // Otherwise the log would publish a version that cannot be restored.
    const { client, keys, store } = await harness();
    await client.push([{ path: 'plan.md', bytes: enc('en') }], AT);

    const routes = createVaultRoutes(store, crypto);
    const { signPayload } = await import('@shade/server');
    const { toBase64 } = await import('@shade/core');
    const log = await store.log(keys.vaultId);
    const body = await signPayload(crypto, keys.signingSeed, {
      manifest: log[0]!.manifest,
      seq: 2,
      at: AT,
      hashes: ['a'.repeat(64)],
      publicKey: toBase64(keys.publicKey),
    });

    const res = await routes.fetch(
      new Request(`http://v/v1/vault/${keys.vaultId}/commit`, {
        method: 'POST',
        headers: { 'content-type': 'application/json' },
        body: JSON.stringify(body),
      }),
    );
    expect(res.status).toBe(409);
    expect((await res.json()).error.code).toBe('MISSING_OBJECTS');
  });
});

describe('authorisation', () => {
  test('a second key cannot write to a vault another key pinned', async () => {
    const { client, keys, store } = await harness();
    await client.push([{ path: 'plan.md', bytes: enc('mitt') }], AT);

    const routes = createVaultRoutes(store, crypto);
    const { signPayload } = await import('@shade/server');
    const { toBase64 } = await import('@shade/core');
    const attacker = await deriveVaultKeys(new Uint8Array(32).fill(9), 'scaffold');

    // Signed correctly — but by the wrong key, and asserting its own pubkey.
    const body = await signPayload(crypto, attacker.signingSeed, {
      data: toBase64(enc('tull')),
      publicKey: toBase64(attacker.publicKey),
    });
    const res = await routes.fetch(
      new Request(
        `http://v/v1/vault/${keys.vaultId}/object/${objectHash(enc('tull'))}`,
        {
          method: 'PUT',
          headers: { 'content-type': 'application/json' },
          body: JSON.stringify(body),
        },
      ),
    );
    expect(res.status).toBe(401);
  });

  test('an unsigned write is refused', async () => {
    const store = new MemoryVaultStore();
    const routes = createVaultRoutes(store, crypto);
    const res = await routes.fetch(
      new Request(`http://v/v1/vault/${'a'.repeat(64)}/object/${'b'.repeat(64)}`, {
        method: 'PUT',
        headers: { 'content-type': 'application/json' },
        body: JSON.stringify({ data: 'aGk=' }),
      }),
    );
    expect(res.status).toBe(401);
  });
});

describe('key derivation', () => {
  test('the same credentials derive the same vault, different ones do not', async () => {
    const a = await deriveVaultKeys(new Uint8Array(32).fill(4), 'scaffold');
    const b = await deriveVaultKeys(new Uint8Array(32).fill(4), 'scaffold');
    const c = await deriveVaultKeys(new Uint8Array(32).fill(5), 'scaffold');
    expect(a.vaultId).toBe(b.vaultId);
    expect(a.vaultId).not.toBe(c.vaultId);
  });

  test('two apps under one master do not share a vault', async () => {
    const master = new Uint8Array(32).fill(6);
    const scaffold = await deriveVaultKeys(master, 'scaffold');
    const mail = await deriveVaultKeys(master, 'mail');
    expect(scaffold.vaultId).not.toBe(mail.vaultId);
    expect(scaffold.contentKey).not.toEqual(mail.contentKey);
  });

  test('the vault branch is separate from the profile-blob branch', async () => {
    // A vault key reads every file; a profile-blob key reads a host list.
    // Sharing a derivation would make one compromise into the other.
    const master = new Uint8Array(32).fill(8);
    const { deriveBlobKey } = await import('@shade/storage-encrypted');
    const vault = await deriveVaultKeys(master, 'prism');
    expect(vault.contentKey).not.toEqual(deriveBlobKey(master, 'prism'));
  });
});