import test from 'node:test';
import assert from 'node:assert/strict';
import { generateKeyPairSync } from 'node:crypto';
import {
  assertLoadedNodeRegistrationSnapshot,
  NodeRegistrationSnapshotLoader,
} from './node-registration-snapshot.js';

const COMMIT = 'a'.repeat(40);
const ANCHOR_URL = 'https://guanghulab.com/api/ai/v1/anchor';
const REGISTRY_URL = `https://guanghulab.com/code/bingshuo/guanghu-ice-heart/raw/commit/${COMMIT}/routing/node-registration-endpoints.json`;
const { publicKey } = generateKeyPairSync('ed25519');

function anchor(includeMap = true) {
  return {
    schema: 'guanghu.public-navigation-anchor/v1',
    anchor_id: 'GLW-PUBLIC-NAV-ANCHOR-001',
    state: 'CURRENT_CANONICAL',
    repository_id: 'REPO-012',
    branch: 'main',
    public_entry: ANCHOR_URL,
    code_entry: 'https://guanghulab.com/code/bingshuo/guanghu-ice-heart',
    maps: includeMap ? {
      node_registration_endpoints: {
        path: 'routing/node-registration-endpoints.json',
        id: 'GH-AIOS-NODE-REGISTRATION-ENDPOINTS-001',
        version: '1.0.0',
      },
    } : {},
    navigation_source: {
      anchor_id: 'GLW-PUBLIC-NAV-ANCHOR-001',
      source_commit: COMMIT,
      source_mode: 'REPO-012_MAIN_GIT_SNAPSHOT',
      source_degraded: false,
    },
  };
}

function registry(version = '1.0.0') {
  return {
    endpoints: [{
      algorithm: 'Ed25519',
      domainIds: ['DOM-FIFTH-0001'],
      endpointId: 'GH-NODE-REG-001',
      nodeTypes: ['local-terminal'],
      publicKeyPem: publicKey.export({ format: 'pem', type: 'spki' }).toString(),
      signerId: 'GH-NODE-REG-SIGNER-001',
      status: 'ACTIVE',
      url: 'https://guanghulab.com/api/ai/v1/node-registrations/claims',
    }],
    registryId: 'GH-AIOS-NODE-REGISTRATION-ENDPOINTS-001',
    schema: 'gh-aios.node-registration-endpoints/v1',
    state: 'CURRENT',
    version,
  };
}

function loader(readAnchor: () => unknown, readRegistry: () => unknown) {
  return new NodeRegistrationSnapshotLoader({
    async fetchJson(url) {
      if (url === ANCHOR_URL) return readAnchor();
      if (url === REGISTRY_URL) return readRegistry();
      throw new Error('unexpected_url');
    },
  });
}

test('loads one exact registry from the anchor source commit', async () => {
  const snapshot = await loader(() => anchor(), () => registry()).refresh();
  assert.equal(snapshot.receipt.status, 'CURRENT');
  assert.equal(snapshot.receipt.sourceCommit, COMMIT);
  assert.equal(snapshot.receipt.endpointCount, 1);
  assert.equal(assertLoadedNodeRegistrationSnapshot(snapshot), snapshot);
});

test('the current public anchor without a registration map is explicitly unavailable', async () => {
  const snapshot = await loader(() => anchor(false), () => registry()).refresh();
  assert.deepEqual(snapshot.receipt, {
    endpointCount: 0,
    reason: 'REGISTRY_UNREGISTERED',
    registryVersion: null,
    sourceCommit: null,
    status: 'UNAVAILABLE',
  });
  assert.equal(snapshot.registry, null);
});

test('source and registry mismatches fail closed', async () => {
  const unavailable = await loader(() => { throw new Error('offline'); }, () => registry()).refresh();
  assert.equal(unavailable.receipt.reason, 'SOURCE_UNAVAILABLE');
  const invalid = await loader(() => anchor(), () => registry('2.0.0')).refresh();
  assert.equal(invalid.receipt.reason, 'REGISTRY_INVALID');
});

test('last-known-good state is reported degraded and cannot be mistaken for current', async () => {
  let currentAnchor: unknown = anchor();
  const snapshotLoader = loader(() => currentAnchor, () => registry());
  await snapshotLoader.refresh();
  currentAnchor = anchor(false);
  const degraded = await snapshotLoader.refresh();
  assert.equal(degraded.receipt.status, 'DEGRADED_LAST_KNOWN_GOOD');
  assert.equal(degraded.receipt.reason, 'REGISTRY_UNREGISTERED');
  assert.equal(degraded.receipt.sourceCommit, COMMIT);
});

test('caller-created snapshots are rejected', () => {
  assert.throws(() => assertLoadedNodeRegistrationSnapshot({
    receipt: { endpointCount: 0, registryVersion: null, sourceCommit: null, status: 'UNAVAILABLE' },
    registry: null,
  }), /snapshot_unregistered/);
});