import assert from 'node:assert/strict';
import test from 'node:test';

import {
  parseSubscriptionBody,
  selectRefreshedServer,
} from '../../dist/server/subscription.js';
import { createServerId } from '../../dist/shared/serverIdentity.js';

const parse = (outbounds) => parseSubscriptionBody(JSON.stringify({ outbounds }));
const outbound = (tag, server, server_port = 443) => ({
  type: 'vless',
  tag,
  server,
  server_port,
});

test('duplicate labels remain independently addressable by stable ID', () => {
  const { config, servers } = parse([
    outbound('Amsterdam', 'nl-1.example'),
    outbound('Amsterdam', 'nl-2.example'),
  ]);

  assert.equal(servers.length, 2);
  assert.equal(servers[0].label, 'Amsterdam');
  assert.equal(servers[1].label, 'Amsterdam');
  assert.notEqual(servers[0].id, servers[1].id);
  assert.deepEqual(config.outbounds.map((item) => item.tag), servers.map((server) => server.id));
});

test('provider reorder does not change server IDs or selection', () => {
  const before = parse([outbound('DE', 'de.example'), outbound('NL', 'nl.example')]).servers;
  const after = parse([outbound('NL', 'nl.example'), outbound('DE', 'de.example')]).servers;
  const selectedId = before[1].id;

  assert.deepEqual(
    new Map(after.map((server) => [server.host, server.id])),
    new Map(before.map((server) => [server.host, server.id])),
  );
  assert.equal(selectRefreshedServer(selectedId, before, after), selectedId);
});

test('cosmetic rename keeps selection for the same endpoint', () => {
  const before = parse([outbound('Old name', 'nl.example')]).servers;
  const after = parse([outbound('New name', 'nl.example')]).servers;

  assert.equal(after[0].id, before[0].id);
  assert.equal(selectRefreshedServer(before[0].id, before, after), before[0].id);
});

test('removed selected server requires an explicit new choice', () => {
  const before = parse([outbound('DE', 'de.example'), outbound('NL', 'nl.example')]).servers;
  const after = parse([outbound('DE', 'de.example')]).servers;

  assert.equal(selectRefreshedServer(before[1].id, before, after), '');
  assert.equal(selectRefreshedServer('', before, after), '');
});

test('provider placeholders never become selectable servers', () => {
  const disabled = outbound('🚫 Subscription disabled', '0.0.0.0', 1);
  const trafficExhausted = outbound('🚫 Traffic limit exceeded', '0.0.0.0', 1);

  assert.throws(
    () => parse([disabled]),
    (error) => error.code === 'SUBSCRIPTION_DISABLED',
  );
  assert.throws(
    () => parse([outbound('Account error', '::', 1)]),
    (error) => error.code === 'SUBSCRIPTION_REJECTED',
  );
  assert.throws(
    () => parse([trafficExhausted]),
    (error) => error.code === 'SUBSCRIPTION_TRAFFIC_EXHAUSTED',
  );

  const parsed = parse([disabled, outbound('Amsterdam', 'nl.example')]);
  assert.deepEqual(parsed.servers.map((server) => server.label), ['Amsterdam']);
  assert.equal(parsed.config.outbounds.length, 1);
});

test('subscription parser rejects JSON primitives and arrays', () => {
  for (const value of [null, [], 42, true, 'provider rejected']) {
    assert.throws(
      () => parseSubscriptionBody(JSON.stringify(value)),
      (error) => error.code === 'SUBSCRIPTION_INVALID',
      `expected ${JSON.stringify(value)} to be rejected`,
    );
  }
});

test('mixed Base64 VLESS feed keeps Reality TCP and TLS WebSocket servers', () => {
  const reality = 'vless://00000000-0000-4000-8000-000000000001@reality.example.test:443?security=reality&type=tcp&pbk=public-key&sid=short-id&sni=cover.example.test&fp=chrome#Reality';
  const websocket = 'vless://00000000-0000-4000-8000-000000000002@ws.example.test:8443?encryption=none&security=tls&sni=edge.example.test&fp=firefox&alpn=h2%2Chttp%2F1.1&type=ws&host=edge.example.test&path=%2Fsocket%3Fed%3D2048#TLS%20WS';
  const websocketVariant = 'vless://00000000-0000-4000-8000-000000000002@ws.example.test:8443?encryption=none&security=tls&sni=edge.example.test&fp=firefox&alpn=h2%2Chttp%2F1.1&type=ws&host=edge.example.test&path=%2Fsecond#TLS%20WS%202';
  const { config, servers } = parseSubscriptionBody(
    Buffer.from(`${reality}\n${websocket}\n${websocketVariant}`).toString('base64'),
  );
  const [realityOutbound, websocketOutbound, websocketVariantOutbound] = config.outbounds;
  const singleton = parseSubscriptionBody(Buffer.from(websocket).toString('base64'));
  const reordered = parseSubscriptionBody(
    Buffer.from(`${websocketVariant.replace('TLS%20WS%202', 'Renamed')}\n${websocket.replace('TLS%20WS', 'Also%20renamed')}\n${reality}`).toString('base64'),
  );
  const idsByPath = (outbounds) => Object.fromEntries(outbounds
    .filter((outbound) => outbound.transport?.type === 'ws')
    .map((outbound) => [outbound.transport.path, outbound.tag]));

  assert.equal(servers.length, 3);
  assert.notEqual(websocketOutbound.tag, websocketVariantOutbound.tag);
  assert.equal(singleton.servers[0].id, websocketOutbound.tag);
  assert.notEqual(singleton.servers[0].id, createServerId(singleton.config.outbounds[0]));
  assert.deepEqual(idsByPath(reordered.config.outbounds), idsByPath(config.outbounds));
  assert.deepEqual(realityOutbound.tls.reality, {
    enabled: true,
    public_key: 'public-key',
    short_id: 'short-id',
  });
  assert.equal(realityOutbound.transport, undefined);
  assert.deepEqual(websocketOutbound.tls, {
    enabled: true,
    server_name: 'edge.example.test',
    alpn: ['h2', 'http/1.1'],
    utls: { enabled: true, fingerprint: 'firefox' },
  });
  assert.deepEqual(websocketOutbound.transport, {
    type: 'ws',
    path: '/socket?ed=2048',
    headers: { Host: 'edge.example.test' },
  });
  assert.equal(websocketOutbound.packet_encoding, 'xudp');
  assert.equal(websocketVariantOutbound.transport.path, '/second');
  const legacyWebsocketId = createServerId(singleton.config.outbounds[0]);
  const legacyWebsocket = [{ ...singleton.servers[0], id: legacyWebsocketId }];
  assert.equal(selectRefreshedServer(
    legacyWebsocketId,
    legacyWebsocket,
    singleton.servers,
  ), singleton.servers[0].id);
  assert.equal(selectRefreshedServer(
    legacyWebsocketId,
    legacyWebsocket,
    servers.slice(1),
  ), '');
  assert.equal(selectRefreshedServer(
    legacyWebsocketId,
    legacyWebsocket,
    [legacyWebsocket[0], singleton.servers[0]],
  ), '');
  assert.equal(selectRefreshedServer(
    websocketOutbound.tag,
    servers,
    [servers[0], servers[2]],
  ), '');
  assert.throws(
    () => parseSubscriptionBody('vless://00000000-0000-4000-8000-000000000003@grpc.example.test:443?security=tls&type=grpc&pbk=public-key&sid=short-id'),
    (error) => error.code === 'SUBSCRIPTION_INVALID',
  );
  assert.equal(
    parseSubscriptionBody(reality.replace('type=tcp', 'type=raw')).config.outbounds[0].transport,
    undefined,
  );
});