Source: http/server.js

/*!
 * server.js - http server for bcoin
 * Copyright (c) 2014-2015, Fedor Indutny (MIT License)
 * Copyright (c) 2014-2017, Christopher Jeffrey (MIT License).
 * https://github.com/bcoin-org/bcoin
 */

'use strict';

/* jshint -W069 */
/* jshint noyield: true */

var assert = require('assert');
var EventEmitter = require('events').EventEmitter;
var HTTPBase = require('./base');
var util = require('../utils/util');
var co = require('../utils/co');
var IP = require('../utils/ip');
var base58 = require('../utils/base58');
var Amount = require('../btc/amount');
var Address = require('../primitives/address');
var Bloom = require('../utils/bloom');
var TX = require('../primitives/tx');
var KeyRing = require('../primitives/keyring');
var Outpoint = require('../primitives/outpoint');
var HD = require('../hd/hd');
var Script = require('../script/script');
var crypto = require('../crypto/crypto');
var Network = require('../protocol/network');
var pkg = require('../../package.json');
var cob = co.cob;
var RPC;

/**
 * HTTPServer
 * @alias module:http.Server
 * @constructor
 * @param {Object} options
 * @param {Fullnode} options.node
 * @see HTTPBase
 * @emits HTTPServer#websocket
 */

function HTTPServer(options) {
  if (!(this instanceof HTTPServer))
    return new HTTPServer(options);

  EventEmitter.call(this);

  this.options = new HTTPOptions(options);

  this.network = this.options.network;
  this.logger = this.options.logger;
  this.node = this.options.node;

  this.chain = this.node.chain;
  this.mempool = this.node.mempool;
  this.pool = this.node.pool;
  this.fees = this.node.fees;
  this.miner = this.node.miner;
  this.wallet = this.node.wallet;
  this.walletdb = this.node.walletdb;

  this.server = new HTTPBase(this.options);
  this.rpc = null;

  this._init();
}

util.inherits(HTTPServer, EventEmitter);

/**
 * Initialize routes.
 * @private
 */

HTTPServer.prototype._init = function _init() {
  var self = this;

  this.server.on('request', function(req, res) {
    if (req.method === 'POST' && req.pathname === '/')
      return;

    self.logger.debug('Request for method=%s path=%s (%s).',
      req.method, req.pathname, req.socket.remoteAddress);
  });

  this.server.on('listening', function(address) {
    self.logger.info('HTTP server listening on %s (port=%d).',
      address.address, address.port);
  });

  this.use(co(function* (req, res) {
    res.setHeader('Access-Control-Allow-Origin', '*');
    res.setHeader('Access-Control-Allow-Credentials', 'true');
    res.setHeader(
      'Access-Control-Allow-Methods',
      'GET,HEAD,PUT,PATCH,POST,DELETE');

    if (req.method === 'OPTIONS') {
      res.statusCode = 200;
      res.sent = true;
      res.end();
      return;
    }

    res.setHeader('X-Bcoin-Version', pkg.version);
    res.setHeader('X-Bcoin-Agent', this.pool.options.agent);
    res.setHeader('X-Bcoin-Network', this.network.type);
    res.setHeader('X-Bcoin-Height', this.chain.height + '');
    res.setHeader('X-Bcoin-Tip', this.chain.tip.rhash());
  }));

  this.use(co(function* (req, res) {
    var auth = req.headers['authorization'];
    var parts;

    if (!auth) {
      req.username = null;
      req.password = null;
      return;
    }

    parts = auth.split(' ');
    assert(parts.length === 2, 'Invalid auth token.');
    assert(parts[0] === 'Basic', 'Invalid auth token.');

    auth = new Buffer(parts[1], 'base64').toString('utf8');
    parts = auth.split(':');

    req.username = parts.shift();
    req.password = parts.join(':');
  }));

  this.use(co(function* (req, res) {
    var hash;

    if (this.options.noAuth) {
      req.admin = true;
      return;
    }

    hash = hash256(req.password);

    // Regular API key gives access to everything.
    if (crypto.ccmp(hash, this.options.apiHash)) {
      req.admin = true;
      return;
    }

    // If they're hitting the wallet services,
    // they can use the less powerful API key.
    if (isWalletPath(req)) {
      if (crypto.ccmp(hash, this.options.serviceHash))
        return;
    }

    res.setHeader('WWW-Authenticate', 'Basic realm="node"');

    if (req.method === 'POST'
        && req.pathname === '/') {
      res.send(401, {
        result: null,
        error: {
          message: 'Bad auth.',
          code: 1
        },
        id: req.body.id
      });
      return;
    }

    res.send(401, { error: 'Bad API key.' });
  }));

  this.hook(co(function* (req, res) {
    var i, params, options, censored, output, address;

    if (req.method === 'POST' && req.pathname === '/') {
      req.options = Object.create(null);
      return;
    }

    params = Object.create(null);
    options = Object.create(null);
    censored = Object.create(null);

    softMerge(params, req.params, true);
    softMerge(params, req.query, true);
    softMerge(params, req.body);
    softMerge(censored, params);

    this.logger.debug('Params:');

    // Censor sensitive data from logs.
    if (censored.passphrase != null)
      censored.passphrase = '<redacted>';

    if (censored.old != null)
      censored.old = '<redacted>';

    if (censored.privateKey != null)
      censored.privateKey = '<redacted>';

    if (censored.accountKey != null)
      censored.accountKey = '<redacted>';

    if (censored.master != null)
      censored.master = '<redacted>';

    if (censored.mnemonic != null)
      censored.mnemonic = '<redacted>';

    if (censored.token != null)
      censored.token = '<redacted>';

    this.logger.debug(censored);

    if (params.id) {
      enforce(typeof params.id === 'string', 'ID must be a string.');
      options.id = params.id;
    }

    if (params.block != null) {
      if (typeof params.block === 'number') {
        assert(util.isUInt32(params.block), 'Height must be a number.');
        options.height = params.block;
      } else {
        enforce(typeof params.block === 'string', 'Hash must be a string.');
        if (params.block.length !== 64) {
          options.height = Number(params.block);
          enforce(util.isUInt32(options.height), 'Height must be a number.');
        } else {
          options.hash = util.revHex(params.block);
        }
      }
    }

    if (params.hash) {
      enforce(typeof params.hash === 'string', 'Hash must be a string.');
      enforce(params.hash.length === 64, 'Hash must be a string.');
      options.hash = util.revHex(params.hash);
    }

    if (params.index != null) {
      options.index = Number(params.index);
      enforce(util.isUInt32(options.index), 'Index must be a number.');
    }

    if (params.height != null) {
      options.height = Number(params.height);
      enforce(util.isUInt32(options.height), 'Height must be a number.');
    }

    if (params.start != null) {
      options.start = Number(params.start);
      enforce(util.isUInt32(options.start), 'Start must be a number.');
    }

    if (params.end != null) {
      options.end = Number(params.end);
      enforce(util.isUInt32(options.end), 'End must be a number.');
    }

    if (params.limit != null) {
      options.limit = Number(params.limit);
      enforce(util.isUInt32(options.limit), 'Limit must be a number.');
    }

    if (params.age != null) {
      options.age = Number(params.age);
      enforce(util.isUInt32(options.age), 'Age must be a number.');
    }

    if (params.confirmations != null) {
      options.depth = Number(params.confirmations);
      enforce(util.isNumber(options.depth),
        'Confirmations must be a number.');
    }

    if (params.depth != null) {
      options.depth = Number(params.depth);
      enforce(util.isNumber(options.depth),
        'Depth must be a number.');
    }

    if (params.fee)
      options.fee = Amount.value(params.fee);

    if (params.hardFee)
      options.hardFee = Amount.value(params.hardFee);

    if (params.maxFee)
      options.maxFee = Amount.value(params.maxFee);

    if (params.rate)
      options.rate = Amount.value(params.rate);

    if (params.m != null) {
      options.m = Number(params.m);
      enforce(util.isUInt32(options.m), 'm must be a number.');
    }

    if (params.n != null) {
      options.n = Number(params.n);
      enforce(util.isUInt32(options.n), 'n must be a number.');
    }

    if (params.blocks != null) {
      options.blocks = Number(params.blocks);
      enforce(util.isUInt32(options.blocks), 'Blocks must be a number.');
    }

    if (params.subtractFee != null) {
      if (typeof params.subtractFee === 'number') {
        options.subtractFee = params.subtractFee;
        enforce(util.isUInt32(options.subtractFee),
          'subtractFee must be a number.');
      } else {
        options.subtractFee = params.subtractFee;
        enforce(typeof options.subtractFee === 'boolean',
          'subtractFee must be a boolean.');
      }
    }

    if (params.watchOnly != null) {
      enforce(typeof params.watchOnly === 'boolean',
        'watchOnly must be a boolean.');
      options.watchOnly = params.watchOnly;
    }

    if (params.accountKey) {
      enforce(typeof params.accountKey === 'string',
        'accountKey must be a string.');
      options.accountKey = HD.fromBase58(params.accountKey);
    }

    if (params.timeout != null) {
      options.timeout = Number(params.timeout);
      enforce(util.isNumber(options.timeout), 'Timeout must be a number.');
    }

    if (params.witness != null) {
      enforce(typeof params.witness === 'boolean',
        'witness must be a boolean.');
      options.witness = params.witness;
    }

    if (params.outputs) {
      enforce(Array.isArray(params.outputs), 'Outputs must be an array.');
      options.outputs = [];
      for (i = 0; i < params.outputs.length; i++) {
        output = params.outputs[i];

        enforce(output && typeof output === 'object',
          'Output must be an object.');

        if (output.address) {
          enforce(typeof output.address === 'string',
            'Address must be a string.');
          output.address = Address.fromBase58(output.address);
          enforce(output.address.verifyNetwork(this.network),
            'Wrong network for address.');
        } else if (output.script) {
          enforce(typeof output.script === 'string',
            'Script must be a string.');
          output.script = Script.fromRaw(output.script, 'hex');
        } else {
          enforce(false, 'No address or script present.');
        }

        options.outputs.push({
          address: output.address || null,
          script: output.script || null,
          value: Amount.value(output.value)
        });
      }
    }

    if (params.address) {
      if (Array.isArray(options.address)) {
        options.address = [];
        for (i = 0; i < params.address.length; i++) {
          address = params.address[i];
          enforce(typeof address === 'string', 'Address must be a string.');
          address = Address.fromBase58(address);
          options.address.push(address);
        }
      } else {
        enforce(typeof params.address === 'string',
          'Address must be a string.');
        options.address = Address.fromBase58(params.address);
      }
    }

    if (params.tx) {
      if (typeof params.tx === 'object') {
        options.tx = TX.fromJSON(params.tx);
      } else {
        enforce(typeof params.tx === 'string',
          'TX must be a hex string.');
        options.tx = TX.fromRaw(params.tx, 'hex');
      }
    }

    if (params.account != null) {
      if (typeof params.account === 'number') {
        options.account = params.account;
        enforce(util.isUInt32(options.account), 'Account must be a number.');
      } else {
        enforce(typeof params.account === 'string',
          'Account must be a string.');
        options.account = params.account;
      }
    }

    if (params.type) {
      enforce(typeof params.type === 'string', 'Type must be a string.');
      options.type = params.type;
    }

    if (params.name) {
      enforce(typeof params.name === 'string', 'Name must be a string.');
      options.name = params.name;
    }

    if (params.privateKey) {
      enforce(typeof params.privateKey === 'string', 'Key must be a string.');
      options.privateKey = KeyRing.fromSecret(params.privateKey);
    }

    if (params.publicKey) {
      enforce(typeof params.publicKey === 'string', 'Key must be a string.');
      options.publicKey = new Buffer(params.publicKey, 'hex');
      options.publicKey = KeyRing.fromKey(options.publicKey, this.network);
    }

    if (params.master) {
      enforce(typeof params.master === 'string', 'Key must be a string.');
      options.master = HD.fromBase58(params.master);
    }

    if (params.mnemonic) {
      enforce(typeof params.mnemonic === 'string', 'Key must be a string.');
      options.master = HD.fromMnemonic(params.mnemonic, this.network);
    }

    if (params.old) {
      enforce(typeof params.old === 'string', 'Passphrase must be a string.');
      enforce(params.old.length > 0, 'Passphrase must be a string.');
      options.old = params.old;
    }

    if (params.passphrase) {
      enforce(typeof params.passphrase === 'string',
        'Passphrase must be a string.');
      enforce(params.passphrase.length > 0, 'Passphrase must be a string.');
      options.passphrase = params.passphrase;
    }

    if (params.token) {
      enforce(util.isHex(params.token), 'Wallet token must be a hex string.');
      enforce(params.token.length === 64, 'Wallet token must be 32 bytes.');
      options.token = new Buffer(params.token, 'hex');
    }

    if (params.path) {
      enforce(typeof params.path === 'string', 'Passphrase must be a string.');
      options.path = params.path;
    }

    req.options = options;
  }));

  this.hook(co(function* (req, res) {
    var options = req.options;
    var wallet;

    if (req.path.length < 2 || req.path[0] !== 'wallet')
      return;

    if (!this.options.walletAuth) {
      wallet = yield this.walletdb.get(options.id);

      if (!wallet) {
        res.send(404);
        return;
      }

      req.wallet = wallet;

      return;
    }

    try {
      wallet = yield this.walletdb.auth(options.id, options.token);
    } catch (err) {
      this.logger.info('Auth failure for %s: %s.',
        req.options.id, err.message);
      res.send(403, { error: err.message });
      return;
    }

    if (!wallet) {
      res.send(404);
      return;
    }

    req.wallet = wallet;

    this.logger.info('Successful auth for %s.', options.id);
  }));

  // JSON RPC
  this.post('/', co(function* (req, res) {
    var out = [];
    var cmds = req.body;
    var array = true;
    var i, cmd, json;

    if (!this.rpc) {
      RPC = require('./rpc');
      this.rpc = new RPC(this.node);
    }

    if (!Array.isArray(cmds)) {
      cmds = [cmds];
      array = false;
    }

    for (i = 0; i < cmds.length; i++) {
      cmd = cmds[i];

      enforce(cmd && typeof cmd === 'object', 'Command must be an object.');
      enforce(typeof cmd.method === 'string', 'Method must be a string.');

      if (!cmd.params)
        cmd.params = [];

      enforce(Array.isArray(cmd.params), 'Params must be an array.');

      if (!cmd.id)
        cmd.id = 0;

      enforce(typeof cmd.id === 'number', 'ID must be a number.');
    }

    for (i = 0; i < cmds.length; i++) {
      cmd = cmds[i];

      if (cmd.method === 'getwork') {
        res.setHeader('X-Long-Polling', '/?longpoll=1');
        if (req.query.longpoll)
          cmd.method = 'getworklp';
      }

      if (cmd.method !== 'getblocktemplate' && cmd.method !== 'getwork') {
        this.logger.debug('Handling RPC call: %s.', cmd.method);
        if (cmd.method !== 'submitblock'
            && cmd.method !== 'getmemorypool') {
          this.logger.debug(cmd.params);
        }
      }

      try {
        json = yield this.rpc.execute(cmd);
      } catch (err) {
        this.logger.error(err);

        if (err.type === 'RPCError') {
          out.push({
            result: null,
            error: {
              message: err.message,
              code: -1
            },
            id: cmd.id
          });
          continue;
        }

        out.push({
          result: null,
          error: {
            message: err.message,
            code: 1
          },
          id: cmd.id
        });

        continue;
      }

      out.push({
        result: json != null ? json : null,
        error: null,
        id: cmd.id
      });
    }

    if (!array) {
      res.send(200, out[0]);
      return;
    }

    res.send(200, out);
  }));

  this.get('/', co(function* (req, res) {
    var totalTX = this.mempool ? this.mempool.totalTX : 0;
    var size = this.mempool ? this.mempool.getSize() : 0;

    res.send(200, {
      version: pkg.version,
      network: this.network.type,
      chain: {
        height: this.chain.height,
        tip: this.chain.tip.rhash(),
        progress: this.chain.getProgress()
      },
      pool: {
        host: this.pool.address.host,
        port: this.pool.address.port,
        agent: this.pool.options.agent,
        services: this.pool.address.services.toString(2),
        outbound: this.pool.peers.outbound,
        inbound: this.pool.peers.inbound
      },
      mempool: {
        tx: totalTX,
        size: size
      },
      time: {
        uptime: this.node.uptime(),
        system: util.now(),
        adjusted: this.network.now(),
        offset: this.network.time.offset
      },
      memory: getMemory()
    });
  }));

  // UTXO by address
  this.get('/coin/address/:address', co(function* (req, res) {
    var coins;

    enforce(req.options.address, 'Address is required.');

    coins = yield this.node.getCoinsByAddress(req.options.address);

    res.send(200, coins.map(function(coin) {
      return coin.getJSON(this.network);
    }, this));
  }));

  // UTXO by id
  this.get('/coin/:hash/:index', co(function* (req, res) {
    var coin;

    enforce(req.options.hash, 'Hash is required.');
    enforce(req.options.index != null, 'Index is required.');

    coin = yield this.node.getCoin(req.options.hash, req.options.index);

    if (!coin) {
      res.send(404);
      return;
    }

    res.send(200, coin.getJSON(this.network));
  }));

  // Bulk read UTXOs
  this.post('/coin/address', co(function* (req, res) {
    var coins;

    enforce(req.options.address, 'Address is required.');

    coins = yield this.node.getCoinsByAddress(req.options.address);

    res.send(200, coins.map(function(coin) {
      return coin.getJSON(this.network);
    }, this));
  }));

  // TX by hash
  this.get('/tx/:hash', co(function* (req, res) {
    var tx;

    enforce(req.options.hash, 'Hash is required.');

    tx = yield this.node.getMeta(req.options.hash);

    if (!tx) {
      res.send(404);
      return;
    }

    res.send(200, tx.getJSON(this.network));
  }));

  // TX by address
  this.get('/tx/address/:address', co(function* (req, res) {
    var txs;

    enforce(req.options.address, 'Address is required.');

    txs = yield this.node.getMetaByAddress(req.options.address);

    res.send(200, txs.map(function(tx) {
      return tx.getJSON(this.network);
    }, this));
  }));

  // Bulk read TXs
  this.post('/tx/address', co(function* (req, res) {
    var txs;

    enforce(req.options.address, 'Address is required.');

    txs = yield this.node.getMetaByAddress(req.options.address);

    res.send(200, txs.map(function(tx) {
      return tx.getJSON(this.network);
    }, this));
  }));

  // Block by hash/height
  this.get('/block/:block', co(function* (req, res) {
    var hash = req.options.hash || req.options.height;
    var block, view, height;

    enforce(hash != null, 'Hash or height required.');

    block = yield this.chain.db.getBlock(hash);

    if (!block) {
      res.send(404);
      return;
    }

    view = yield this.chain.db.getBlockView(block);

    if (!view) {
      res.send(404);
      return;
    }

    height = yield this.chain.db.getHeight(hash);

    res.send(200, block.getJSON(this.network, view, height));
  }));

  // Mempool snapshot
  this.get('/mempool', co(function* (req, res) {
    var txs;

    if (!this.mempool) {
      res.send(500, { error: 'No mempool available.' });
      return;
    }

    txs = this.mempool.getHistory();

    res.send(200, txs.map(function(tx) {
      return tx.getJSON(this.network);
    }, this));
  }));

  // Broadcast TX
  this.post('/broadcast', co(function* (req, res) {
    enforce(req.options.tx, 'TX is required.');
    yield this.node.sendTX(req.options.tx);
    res.send(200, { success: true });
  }));

  // Estimate fee
  this.get('/fee', function(req, res) {
    var fee;

    if (!this.fees) {
      res.send(200, { rate: Amount.btc(this.network.feeRate) });
      return;
    }

    fee = this.fees.estimateFee(req.options.blocks);

    res.send(200, { rate: Amount.btc(fee) });
  });

  // Reset chain
  this.post('/reset', co(function* (req, res) {
    var options = req.options;
    var hash = options.hash || options.height;

    enforce(hash != null, 'Hash or height is required.');

    yield this.chain.reset(hash);

    res.send(200, { success: true });
  }));

  // Rescan
  this.post('/rescan', co(function* (req, res) {
    var options = req.options;
    var height = options.height;

    res.send(200, { success: true });

    yield this.walletdb.rescan(height);
  }));

  // Resend
  this.post('/resend', co(function* (req, res) {
    yield this.walletdb.resend();
    res.send(200, { success: true });
  }));

  // Backup WalletDB
  this.post('/backup', co(function* (req, res) {
    var options = req.options;
    var path = options.path;

    enforce(path, 'Path is required.');

    yield this.walletdb.backup(path);

    res.send(200, { success: true });
  }));

  // List wallets
  this.get('/wallets', co(function* (req, res) {
    var wallets = yield this.walletdb.getWallets();
    res.send(200, wallets);
  }));

  // Get wallet
  this.get('/wallet/:id', function(req, res) {
    res.send(200, req.wallet.toJSON());
  });

  // Get wallet master key
  this.get('/wallet/:id/master', function(req, res) {
    if (!req.admin) {
      res.send(403, { error: 'Admin access required.' });
      return;
    }

    res.send(200, req.wallet.master.toJSON(true));
  });

  // Create wallet
  this.post('/wallet/:id?', co(function* (req, res) {
    var wallet = yield this.walletdb.create(req.options);
    res.send(200, wallet.toJSON());
  }));

  // List accounts
  this.get('/wallet/:id/account', co(function* (req, res) {
    var accounts = yield req.wallet.getAccounts();
    res.send(200, accounts);
  }));

  // Get account
  this.get('/wallet/:id/account/:account', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var account;

    enforce(acct != null, 'Account is required.');

    account = yield req.wallet.getAccount(acct);

    if (!account) {
      res.send(404);
      return;
    }

    res.send(200, account.toJSON());
  }));

  // Create account
  this.post('/wallet/:id/account/:account?', co(function* (req, res) {
    var options = req.options;
    var passphrase = options.passphrase;
    var account;

    if (typeof options.account === 'string') {
      options.name = options.account;
      options.account = null;
    }

    account = yield req.wallet.createAccount(options, passphrase);

    if (!account) {
      res.send(404);
      return;
    }

    res.send(200, account.toJSON());
  }));

  // Change passphrase
  this.post('/wallet/:id/passphrase', co(function* (req, res) {
    var options = req.options;
    var old = options.old;
    var new_ = options.passphrase;
    enforce(old || new_, 'Passphrase is required.');
    yield req.wallet.setPassphrase(old, new_);
    res.send(200, { success: true });
  }));

  // Unlock wallet
  this.post('/wallet/:id/unlock', co(function* (req, res) {
    var options = req.options;
    var passphrase = options.passphrase;
    var timeout = options.timeout;
    enforce(passphrase, 'Passphrase is required.');
    yield req.wallet.unlock(passphrase, timeout);
    res.send(200, { success: true });
  }));

  // Lock wallet
  this.post('/wallet/:id/lock', co(function* (req, res) {
    yield req.wallet.lock();
    res.send(200, { success: true });
  }));

  // Import key
  this.post('/wallet/:id/import', co(function* (req, res) {
    var options = req.options;
    var acct = req.options.name || req.options.account;
    var key = options.privateKey || options.publicKey;

    if (key) {
      yield req.wallet.importKey(acct, key);
      res.send(200, { success: true });
      return;
    }

    if (options.address) {
      enforce(options.address instanceof Address, 'Address is required.');
      yield req.wallet.importAddress(acct, options.address);
      res.send(200, { success: true });
      return;
    }

    enforce(false, 'Key or address is required.');
  }));

  // Generate new token
  this.post('/wallet/:id/retoken', co(function* (req, res) {
    var options = req.options;
    var token = yield req.wallet.retoken(options.passphrase);
    res.send(200, { token: token.toString('hex') });
  }));

  // Send TX
  this.post('/wallet/:id/send', co(function* (req, res) {
    var options = req.options;
    var passphrase = options.passphrase;
    var tx = yield req.wallet.send(options, passphrase);
    var details = yield req.wallet.getDetails(tx.hash('hex'));
    res.send(200, details.toJSON());
  }));

  // Create TX
  this.post('/wallet/:id/create', co(function* (req, res) {
    var options = req.options;
    var passphrase = options.passphrase;
    var tx = yield req.wallet.createTX(options);
    yield req.wallet.sign(tx, passphrase);
    res.send(200, tx.getJSON(this.network));
  }));

  // Sign TX
  this.post('/wallet/:id/sign', co(function* (req, res) {
    var options = req.options;
    var passphrase = options.passphrase;
    var tx = req.options.tx;
    enforce(tx, 'TX is required.');
    yield req.wallet.sign(tx, passphrase);
    res.send(200, tx.getJSON(this.network));
  }));

  // Zap Wallet TXs
  this.post('/wallet/:id/zap', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var age = options.age;
    enforce(age, 'Age is required.');
    yield req.wallet.zap(acct, age);
    res.send(200, { success: true });
  }));

  // Abandon Wallet TX
  this.del('/wallet/:id/tx/:hash', co(function* (req, res) {
    var hash = req.options.hash;
    enforce(hash, 'Hash is required.');
    yield req.wallet.abandon(hash);
    res.send(200, { success: true });
  }));

  // List blocks
  this.get('/wallet/:id/block', co(function* (req, res) {
    var heights = yield req.wallet.getBlocks();
    res.send(200, heights);
  }));

  // Get Block Record
  this.get('/wallet/:id/block/:height', co(function* (req, res) {
    var height = req.options.height;
    var block;

    enforce(height != null, 'Height is required.');

    block = yield req.wallet.getBlock(height);

    if (!block) {
      res.send(404);
      return;
    }

    res.send(200, block.toJSON());
  }));

  // Add key
  this.put('/wallet/:id/shared-key', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var key = options.accountKey;
    enforce(key, 'Key is required.');
    yield req.wallet.addSharedKey(acct, key);
    res.send(200, { success: true });
  }));

  // Remove key
  this.del('/wallet/:id/shared-key', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var key = options.accountKey;
    enforce(key, 'Key is required.');
    yield req.wallet.removeSharedKey(acct, key);
    res.send(200, { success: true });
  }));

  // Get key by address
  this.get('/wallet/:id/key/:address', co(function* (req, res) {
    var options = req.options;
    var address = options.address;
    var key;

    enforce(address instanceof Address, 'Address is required.');

    key = yield req.wallet.getKey(address);

    if (!key) {
      res.send(404);
      return;
    }

    res.send(200, key.toJSON());
  }));

  // Get private key
  this.get('/wallet/:id/wif/:address', co(function* (req, res) {
    var options = req.options;
    var address = options.address;
    var passphrase = options.passphrase;
    var key;

    enforce(address instanceof Address, 'Address is required.');

    key = yield req.wallet.getPrivateKey(address, passphrase);

    if (!key) {
      res.send(404);
      return;
    }

    res.send(200, { privateKey: key.toSecret() });
  }));

  // Create address
  this.post('/wallet/:id/address', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var address = yield req.wallet.createReceive(acct);
    res.send(200, address.toJSON());
  }));

  // Create change address
  this.post('/wallet/:id/change', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var address = yield req.wallet.createChange(acct);
    res.send(200, address.toJSON());
  }));

  // Create nested address
  this.post('/wallet/:id/nested', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var address = yield req.wallet.createNested(acct);
    res.send(200, address.toJSON());
  }));

  // Wallet Balance
  this.get('/wallet/:id/balance', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var balance = yield req.wallet.getBalance(acct);

    if (!balance) {
      res.send(404);
      return;
    }

    res.send(200, balance.toJSON());
  }));

  // Wallet UTXOs
  this.get('/wallet/:id/coin', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var coins = yield req.wallet.getCoins(acct);

    sortCoins(coins);

    res.send(200, coins.map(function(coin) {
      return coin.getJSON(this.network);
    }, this));
  }));

  // Locked coins
  this.get('/wallet/:id/coin/locked', co(function* (req, res) {
    var locked = this.wallet.getLocked();
    res.send(200, locked.map(function(outpoint) {
      return outpoint.toJSON();
    }));
  }));

  // Lock coin
  this.put('/wallet/:id/coin/locked', co(function* (req, res) {
    var options = req.options.hash;
    var outpoint;

    enforce(options.hash, 'Hash is required.');
    enforce(options.index != null, 'Index is required.');

    outpoint = new Outpoint(options.hash, options.index);

    this.wallet.lockCoin(outpoint);
  }));

  // Unlock coin
  this.del('/wallet/:id/coin/locked', co(function* (req, res) {
    var options = req.options.hash;
    var outpoint;

    enforce(options.hash, 'Hash is required.');
    enforce(options.index != null, 'Index is required.');

    outpoint = new Outpoint(options.hash, options.index);

    this.wallet.unlockCoin(outpoint);
  }));

  // Wallet Coin
  this.get('/wallet/:id/coin/:hash/:index', co(function* (req, res) {
    var hash = req.options.hash;
    var index = req.options.index;
    var coin;

    enforce(hash, 'Hash is required.');
    enforce(index != null, 'Index is required.');

    coin = yield req.wallet.getCoin(hash, index);

    if (!coin) {
      res.send(404);
      return;
    }

    res.send(200, coin.getJSON(this.network));
  }));

  // Wallet TXs
  this.get('/wallet/:id/tx/history', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var txs = yield req.wallet.getHistory(acct);
    var details;

    sortTX(txs);

    details = yield req.wallet.toDetails(txs);

    res.send(200, details.map(function(tx) {
      return tx.toJSON();
    }));
  }));

  // Wallet Pending TXs
  this.get('/wallet/:id/tx/unconfirmed', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var txs = yield req.wallet.getPending(acct);
    var details;

    sortTX(txs);

    details = yield req.wallet.toDetails(txs);

    res.send(200, details.map(function(tx) {
      return tx.toJSON();
    }));
  }));

  // Wallet TXs within time range
  this.get('/wallet/:id/tx/range', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var txs = yield req.wallet.getRange(acct, options);
    var details = yield req.wallet.toDetails(txs);
    res.send(200, details.map(function(tx) {
      return tx.toJSON();
    }));
  }));

  // Last Wallet TXs
  this.get('/wallet/:id/tx/last', co(function* (req, res) {
    var options = req.options;
    var acct = options.name || options.account;
    var limit = options.limit;
    var txs = yield req.wallet.getLast(acct, limit);
    var details = yield req.wallet.toDetails(txs);
    res.send(200, details.map(function(tx) {
      return tx.toJSON();
    }));
  }));

  // Wallet TX
  this.get('/wallet/:id/tx/:hash', co(function* (req, res) {
    var hash = req.options.hash;
    var tx, details;

    enforce(hash, 'Hash is required.');

    tx = yield req.wallet.getTX(hash);

    if (!tx) {
      res.send(404);
      return;
    }

    details = yield req.wallet.toDetails(tx);

    res.send(200, details.toJSON());
  }));

  // Resend
  this.post('/wallet/:id/resend', co(function* (req, res) {
    yield req.wallet.resend();
    res.send(200, { success: true });
  }));

  this.server.on('error', function(err) {
    self.emit('error', err);
  });

  this._initIO();
};

/**
 * Initialize websockets.
 * @private
 */

HTTPServer.prototype._initIO = function _initIO() {
  var self = this;

  if (!this.server.io)
    return;

  this.server.on('websocket', function(ws) {
    var socket = new ClientSocket(self, ws);

    socket.start();

    socket.on('error', function(err) {
      self.emit('error', err);
    });

    socket.on('disconnect', function() {
      socket.destroy();
    });

    socket.on('auth', cob(function* (args) {
      var key = args[0];
      var hash, api, service;

      if (socket.auth)
        throw { error: 'Already authed.' };

      socket.stop();

      if (!self.options.noAuth) {
        hash = hash256(key);
        api = crypto.ccmp(hash, self.options.apiHash);
        service = crypto.ccmp(hash, self.options.serviceHash);

        if (!api && !service)
          throw { error: 'Bad key.' };

        socket.api = api;
      }

      socket.auth = true;

      self.logger.info('Successful auth from %s.', socket.host);

      self.emit('websocket', socket);
    }));

    socket.emit('version', {
      version: pkg.version,
      agent: self.pool.options.agent,
      network: self.network.type
    });
  });

  this.on('websocket', function(socket) {
    socket.on('wallet join', cob(function* (args) {
      var id = args[0];
      var token = args[1];
      var wallet;

      if (typeof id !== 'string')
        throw { error: 'Invalid parameter.' };

      if (!self.options.walletAuth) {
        socket.join(id);
        return;
      }

      if (!util.isHex256(token))
        throw { error: 'Invalid parameter.' };

      token = new Buffer(token, 'hex');

      if (socket.api && id === '!all') {
        socket.join(id);
        return;
      }

      try {
        wallet = yield self.walletdb.auth(id, token);
      } catch (e) {
        self.logger.info('Wallet auth failure for %s: %s.', id, e.message);
        throw { error: 'Bad token.' };
      }

      if (!wallet)
        throw { error: 'Wallet does not exist.' };

      self.logger.info('Successful wallet auth for %s.', id);

      socket.join(id);
    }));

    socket.on('wallet leave', cob(function* (args) {
      var id = args[0];

      if (typeof id !== 'string')
        throw { error: 'Invalid parameter.' };

      socket.leave(id);
    }));

    socket.on('options', cob(function* (args) {
      var options = args[0];
      try {
        socket.setOptions(options);
      } catch (e) {
        throw { error: e.message };
      }
    }));

    socket.on('watch chain', cob(function* (args) {
      if (!socket.api)
        throw { error: 'Not authorized.' };

      try {
        socket.watchChain();
      } catch (e) {
        throw { error: e.message };
      }
    }));

    socket.on('unwatch chain', cob(function* (args) {
      if (!socket.api)
        throw { error: 'Not authorized.' };

      try {
        socket.unwatchChain();
      } catch (e) {
        throw { error: e.message };
      }
    }));

    socket.on('set filter', cob(function* (args) {
      var data = args[0];
      var filter;

      if (!util.isHex(data) && !Buffer.isBuffer(data))
        throw { error: 'Invalid parameter.' };

      if (!socket.api)
        throw { error: 'Not authorized.' };

      try {
        filter = Bloom.fromRaw(data, 'hex');
        socket.setFilter(filter);
      } catch (e) {
        throw { error: e.message };
      }
    }));

    socket.on('get tip', cob(function* (args) {
      return socket.frameEntry(self.chain.tip);
    }));

    socket.on('get entry', cob(function* (args) {
      var block = args[0];
      var entry;

      if (typeof block === 'string') {
        if (!util.isHex256(block))
          throw { error: 'Invalid parameter.' };
        block = util.revHex(block);
      } else {
        if (!util.isUInt32(block))
          throw { error: 'Invalid parameter.' };
      }

      try {
        entry = yield self.chain.db.getEntry(block);
        if (!(yield entry.isMainChain()))
          entry = null;
      } catch (e) {
        throw { error: e.message };
      }

      if (!entry)
        return null;

      return socket.frameEntry(entry);
    }));

    socket.on('add filter', cob(function* (args) {
      var chunks = args[0];

      if (!Array.isArray(chunks))
        throw { error: 'Invalid parameter.' };

      if (!socket.api)
        throw { error: 'Not authorized.' };

      try {
        socket.addFilter(chunks);
      } catch (e) {
        throw { error: e.message };
      }
    }));

    socket.on('reset filter', cob(function* (args) {
      if (!socket.api)
        throw { error: 'Not authorized.' };

      try {
        socket.resetFilter();
      } catch (e) {
        throw { error: e.message };
      }
    }));

    socket.on('estimate fee', cob(function* (args) {
      var blocks = args[0];
      var rate;

      if (blocks != null && !util.isNumber(blocks))
        throw { error: 'Invalid parameter.' };

      if (!self.fees) {
        rate = self.network.feeRate;
        rate = Amount.btc(rate);
        return rate;
      }

      rate = self.fees.estimateFee(blocks);
      rate = Amount.btc(rate);

      return rate;
    }));

    socket.on('send', cob(function* (args) {
      var data = args[0];
      var tx;

      if (!util.isHex(data) && !Buffer.isBuffer(data))
        throw { error: 'Invalid parameter.' };

      try {
        tx = TX.fromRaw(data, 'hex');
      } catch (e) {
        throw { error: 'Invalid parameter.' };
      }

      self.node.send(tx);
    }));

    socket.on('rescan', cob(function* (args) {
      var start = args[0];

      if (!util.isHex256(start) && !util.isUInt32(start))
        throw { error: 'Invalid parameter.' };

      if (!socket.api)
        throw { error: 'Not authorized.' };

      if (typeof start === 'string')
        start = util.revHex(start);

      try {
        yield socket.scan(start);
      } catch (e) {
        throw { error: e.message };
      }
    }));
  });

  this.walletdb.on('tx', function(id, tx, details) {
    var json = details.toJSON();
    self.server.io.to(id).emit('wallet tx', json);
    self.server.io.to('!all').emit('wallet tx', id, json);
  });

  this.walletdb.on('confirmed', function(id, tx, details) {
    var json = details.toJSON();
    self.server.io.to(id).emit('wallet confirmed', json);
    self.server.io.to('!all').emit('wallet confirmed', id, json);
  });

  this.walletdb.on('unconfirmed', function(id, tx, details) {
    var json = details.toJSON();
    self.server.io.to(id).emit('wallet unconfirmed', json);
    self.server.io.to('!all').emit('wallet unconfirmed', id, json);
  });

  this.walletdb.on('conflict', function(id, tx, details) {
    var json = details.toJSON();
    self.server.io.to(id).emit('wallet conflict', json);
    self.server.io.to('!all').emit('wallet conflict', id, json);
  });

  this.walletdb.on('balance', function(id, balance) {
    var json = balance.toJSON();
    self.server.io.to(id).emit('wallet balance', json);
    self.server.io.to('!all').emit('wallet balance', id, json);
  });

  this.walletdb.on('address', function(id, receive) {
    receive = receive.map(function(address) {
      return address.toJSON();
    });
    self.server.io.to(id).emit('wallet address', receive);
    self.server.io.to('!all').emit('wallet address', id, receive);
  });
};

/**
 * Open the server, wait for socket.
 * @returns {Promise}
 */

HTTPServer.prototype.open = co(function* open() {
  yield this.server.open();

  this.logger.info('HTTP server loaded.');

  if (this.options.noAuth) {
    this.logger.warning('WARNING: Your http server is open to the world.');
    return;
  }

  this.logger.info('HTTP API key: %s', this.options.apiKey);
  this.logger.info('HTTP Service API key: %s', this.options.serviceKey);

  this.options.apiKey = null;
  this.options.serviceKey = null;
});

/**
 * Close the server, wait for server socket to close.
 * @returns {Promise}
 */

HTTPServer.prototype.close = function close() {
  return this.server.close();
};

/**
 * Add a middleware to the stack.
 * @param {String?} path
 * @param {Function} handler
 */

HTTPServer.prototype.use = function use(path, handler) {
  if (!handler) {
    handler = path;
    path = null;
  }
  return this.server.use(path, handler, this);
};

/**
 * Add a hook to the stack.
 * @param {String?} path
 * @param {Function} handler
 */

HTTPServer.prototype.hook = function hook(path, handler) {
  if (!handler) {
    handler = path;
    path = null;
  }
  return this.server.hook(path, handler, this);
};

/**
 * Add a GET route.
 * @param {String} path
 * @param {Function} handler
 */

HTTPServer.prototype.get = function get(path, handler) {
  return this.server.get(path, handler, this);
};

/**
 * Add a POST route.
 * @param {String} path
 * @param {Function} handler
 */

HTTPServer.prototype.post = function post(path, handler) {
  return this.server.post(path, handler, this);
};

/**
 * Add a PUT route.
 * @param {String} path
 * @param {Function} handler
 */

HTTPServer.prototype.put = function put(path, handler) {
  return this.server.put(path, handler, this);
};

/**
 * Add a DEL route.
 * @param {String} path
 * @param {Function} handler
 */

HTTPServer.prototype.del = function del(path, handler) {
  return this.server.del(path, handler, this);
};

/**
 * Listen on port and host.
 * @param {Number} port
 * @param {String} host
 * @returns {Promise}
 */

HTTPServer.prototype.listen = function listen(port, host) {
  return this.server.listen(port, host);
};

/**
 * HTTPOptions
 * @alias module:http.HTTPOptions
 * @constructor
 * @param {Object} options
 */

function HTTPOptions(options) {
  if (!(this instanceof HTTPOptions))
    return new HTTPOptions(options);

  this.network = Network.primary;
  this.logger = null;
  this.node = null;
  this.apiKey = base58.encode(crypto.randomBytes(20));
  this.apiHash = hash256(this.apiKey);
  this.serviceKey = this.apiKey;
  this.serviceHash = this.apiHash;
  this.noAuth = false;
  this.walletAuth = false;
  this.sockets = true;
  this.host = '127.0.0.1';
  this.port = this.network.rpcPort;
  this.key = null;
  this.cert = null;
  this.ca = null;

  this.fromOptions(options);
}

/**
 * Inject properties from object.
 * @private
 * @param {Object} options
 * @returns {HTTPOptions}
 */

HTTPOptions.prototype.fromOptions = function fromOptions(options) {
  assert(options);
  assert(options.node && typeof options.node === 'object',
    'HTTP Server requires a Node.');

  this.node = options.node;
  this.network = options.node.network;
  this.logger = options.node.logger;

  this.port = this.network.rpcPort;

  if (options.logger != null) {
    assert(typeof options.logger === 'object');
    this.logger = options.logger;
  }

  if (options.apiKey != null) {
    assert(typeof options.apiKey === 'string',
      'API key must be a string.');
    assert(options.apiKey.length <= 200,
      'API key must be under 200 bytes.');
    this.apiKey = options.apiKey;
    this.apiHash = hash256(this.apiKey);
    this.serviceKey = this.apiKey;
    this.serviceHash = this.apiHash;
  }

  if (options.serviceKey != null) {
    assert(typeof options.serviceKey === 'string',
      'API key must be a string.');
    assert(options.serviceKey.length <= 200,
      'API key must be under 200 bytes.');
    this.serviceKey = options.serviceKey;
    this.serviceHash = hash256(this.serviceKey);
  }

  if (options.noAuth != null) {
    assert(typeof options.noAuth === 'boolean');
    this.noAuth = options.noAuth;
  }

  if (options.walletAuth != null) {
    assert(typeof options.walletAuth === 'boolean');
    this.walletAuth = options.walletAuth;
  }

  if (options.host != null) {
    assert(typeof options.host === 'string');
    this.host = IP.normalize(options.host);
  }

  if (options.port != null) {
    assert(typeof options.port === 'number', 'Port must be a number.');
    assert(options.port > 0 && options.port <= 0xffff);
    this.port = options.port;
  }

  if (options.key != null) {
    assert(typeof options.key === 'string' || Buffer.isBuffer(options.key));
    this.key = options.key;
  }

  if (options.cert != null) {
    assert(typeof options.cert === 'string' || Buffer.isBuffer(options.cert));
    this.cert = options.cert;
  }

  if (options.ca != null) {
    assert(Array.isArray(options.ca));
    this.ca = options.ca;
  }

  // Allow no-auth implicitly
  // if we're listening locally.
  if (!options.apiKey && !options.serviceKey && options.noAuth == null) {
    if (this.host === '127.0.0.1' || this.host === '::1')
      this.noAuth = true;
  }

  return this;
};

/**
 * Instantiate http options from object.
 * @param {Object} options
 * @returns {HTTPOptions}
 */

HTTPOptions.fromOptions = function fromOptions(options) {
  return new HTTPOptions().fromOptions(options);
};

/**
 * ClientSocket
 * @constructor
 * @ignore
 * @param {HTTPServer} server
 * @param {SocketIO.Socket}
 */

function ClientSocket(server, socket) {
  if (!(this instanceof ClientSocket))
    return new ClientSocket(server, socket);

  EventEmitter.call(this);

  this.server = server;
  this.socket = socket;
  this.host = socket.conn.remoteAddress;
  this.timeout = null;
  this.auth = false;
  this.filter = null;
  this.api = false;
  this.raw = false;
  this.watching = false;

  this.network = this.server.network;
  this.node = this.server.node;
  this.chain = this.server.chain;
  this.mempool = this.server.mempool;
  this.pool = this.server.pool;
  this.logger = this.server.logger;
  this.events = [];

  this._init();
}

util.inherits(ClientSocket, EventEmitter);

ClientSocket.prototype._init = function _init() {
  var self = this;
  var socket = this.socket;
  var emit = EventEmitter.prototype.emit;
  var onevent = socket.onevent.bind(socket);

  socket.onevent = function(packet) {
    var result = onevent(packet);
    var args = packet.data || [];
    var event = args.shift();
    var ack;

    if (typeof args[args.length - 1] === 'function')
      ack = args.pop();
    else
      ack = self.socket.ack(packet.id);

    emit.call(self, event, args, ack);

    return result;
  };

  socket.on('error', function(err) {
    emit.call(self, 'error', err);
  });

  socket.on('disconnect', function() {
    emit.call(self, 'disconnect');
  });
};

ClientSocket.prototype.setOptions = function setOptions(options) {
  assert(options && typeof options === 'object', 'Invalid parameter.');

  if (options.raw != null) {
    assert(typeof options.raw === 'boolean', 'Invalid parameter.');
    this.raw = options.raw;
  }
};

ClientSocket.prototype.setFilter = function setFilter(filter) {
  this.filter = filter;
};

ClientSocket.prototype.addFilter = function addFilter(chunks) {
  var i, data;

  if (!this.filter)
    throw new Error('No filter set.');

  for (i = 0; i < chunks.length; i++) {
    data = chunks[i];

    if (!util.isHex(data) && !Buffer.isBuffer(data))
      throw new Error('Not a hex string.');

    this.filter.add(data, 'hex');

    if (this.pool.options.spv)
      this.pool.watch(data, 'hex');
  }
};

ClientSocket.prototype.resetFilter = function resetFilter() {
  if (!this.filter)
    throw new Error('No filter set.');

  this.filter.reset();
};

ClientSocket.prototype.bind = function bind(obj, event, listener) {
  this.events.push([obj, event, listener]);
  obj.on(event, listener);
};

ClientSocket.prototype.unbind = function unbind(obj, event) {
  var i, item;

  for (i = this.events.length - 1; i >= 0; i--) {
    item = this.events[i];
    if (item[0] === obj && item[1] === event) {
      obj.removeListener(event, item[2]);
      this.events.splice(i, 1);
    }
  }
};

ClientSocket.prototype.unbindAll = function unbindAll() {
  var i, event;

  for (i = 0; i < this.events.length; i++) {
    event = this.events[i];
    event[0].removeListener(event[1], event[2]);
  }

  this.events.length = 0;
};

ClientSocket.prototype.watchChain = function watchChain() {
  var self = this;
  var pool = this.mempool || this.pool;

  if (this.watching)
    throw new Error('Already watching chain.');

  this.watching = true;

  this.bind(this.chain, 'connect', function(entry, block, view) {
    self.connectBlock(entry, block, view);
  });

  this.bind(this.chain, 'disconnect', function(entry, block, view) {
    self.disconnectBlock(entry, block, view);
  });

  this.bind(this.chain, 'reset', function(tip) {
    self.emit('chain reset', self.frameEntry(tip));
  });

  this.bind(pool, 'tx', function(tx) {
    self.sendTX(tx);
  });
};

ClientSocket.prototype.onError = function onError(err) {
  var emit = EventEmitter.prototype.emit;
  emit.call(this, 'error', err);
};

ClientSocket.prototype.unwatchChain = function unwatchChain() {
  var pool = this.mempool || this.pool;

  if (!this.watching)
    throw new Error('Not watching chain.');

  this.watching = false;

  this.unbind(this.chain, 'connect');
  this.unbind(this.chain, 'disconnect');
  this.unbind(this.chain, 'reset');
  this.unbind(pool, 'tx');
};

ClientSocket.prototype.connectBlock = function connectBlock(entry, block, view) {
  var raw = this.frameEntry(entry);
  var txs;

  this.emit('entry connect', raw);

  if (!this.filter)
    return;

  txs = this.filterBlock(entry, block, view);

  this.emit('block connect', raw, txs);
};

ClientSocket.prototype.disconnectBlock = function disconnectBlock(entry, block, view) {
  var raw = this.frameEntry(entry);

  this.emit('entry disconnect', raw);

  if (!this.filter)
    return;

  this.emit('block disconnect', raw);
};

ClientSocket.prototype.sendTX = function sendTX(tx) {
  var raw;

  if (!this.filterTX(tx))
    return;

  raw = this.frameTX(tx);

  this.emit('tx', raw);
};

ClientSocket.prototype.rescanBlock = function rescanBlock(entry, txs) {
  var self = this;
  return new Promise(function(resolve, reject) {
    var cb = TimedCB.wrap(resolve, reject);
    self.emit('block rescan', entry, txs, cb);
  });
};

ClientSocket.prototype.filterBlock = function filterBlock(entry, block, view) {
  var txs = [];
  var i, tx;

  if (!this.filter)
    return;

  for (i = 0; i < block.txs.length; i++) {
    tx = block.txs[i];
    if (this.filterTX(tx))
      txs.push(this.frameTX(tx, view, entry, i));
  }

  return txs;
};

ClientSocket.prototype.filterTX = function filterTX(tx) {
  var found = false;
  var i, hash, input, prevout, output;

  if (!this.filter)
    return false;

  for (i = 0; i < tx.outputs.length; i++) {
    output = tx.outputs[i];
    hash = output.getHash();

    if (!hash)
      continue;

    if (this.filter.test(hash)) {
      prevout = Outpoint.fromTX(tx, i);
      this.filter.add(prevout.toRaw());
      found = true;
    }
  }

  if (found)
    return true;

  if (!tx.isCoinbase()) {
    for (i = 0; i < tx.inputs.length; i++) {
      input = tx.inputs[i];
      prevout = input.prevout;
      if (this.filter.test(prevout.toRaw()))
        return true;
    }
  }

  return false;
};

ClientSocket.prototype.scan = co(function* scan(start) {
  var scanner = this.scanner.bind(this);
  yield this.node.scan(start, this.filter, scanner);
});

ClientSocket.prototype.scanner = function scanner(entry, txs) {
  var block = this.frameEntry(entry);
  var raw = new Array(txs.length);
  var i;

  for (i = 0; i < txs.length; i++)
    raw[i] = this.frameTX(txs[i], null, entry, i);

  return this.rescanBlock(block, raw);
};

ClientSocket.prototype.frameEntry = function frameEntry(entry) {
  if (this.raw)
    return entry.toRaw();
  return entry.toJSON();
};

ClientSocket.prototype.frameTX = function frameTX(tx, view, entry, index) {
  if (this.raw)
    return tx.toRaw();
  return tx.getJSON(this.network, view, entry, index);
};

ClientSocket.prototype.join = function join(id) {
  this.socket.join(id);
};

ClientSocket.prototype.leave = function leave(id) {
  this.socket.leave(id);
};

ClientSocket.prototype.emit = function emit() {
  this.socket.emit.apply(this.socket, arguments);
};

ClientSocket.prototype.start = function start() {
  var self = this;
  this.stop();
  this.timeout = setTimeout(function() {
    self.timeout = null;
    self.destroy();
  }, 60000);
};

ClientSocket.prototype.stop = function stop() {
  if (this.timeout != null) {
    clearTimeout(this.timeout);
    this.timeout = null;
  }
};

ClientSocket.prototype.destroy = function() {
  this.unbindAll();
  this.stop();
  this.socket.disconnect();
};

/*
 * Helpers
 */

function hash256(data) {
  if (typeof data !== 'string')
    return new Buffer(0);
  if (data.length > 200)
    return new Buffer(0);
  return crypto.hash256(new Buffer(data, 'utf8'));
}

function softMerge(a, b, soft) {
  var keys = Object.keys(b);
  var i, key, value;
  for (i = 0; i < keys.length; i++) {
    key = keys[i];
    value = b[key];
    if (!soft || value)
      a[key] = value;
  }
}

function enforce(value, msg) {
  var err;

  if (!value) {
    err = new Error(msg);
    err.statusCode = 400;
    throw err;
  }
}

function sortTX(txs) {
  return txs.sort(function(a, b) {
    return a.ps - b.ps;
  });
}

function sortCoins(coins) {
  return coins.sort(function(a, b) {
    a = a.height === -1 ? 0x7fffffff : a.height;
    b = b.height === -1 ? 0x7fffffff : b.height;
    return a - b;
  });
}

function isWalletPath(req) {
  if (req.path.length >= 1 && req.path[0] === 'wallet')
    return true;

  if (req.method === 'GET' && req.pathname === '/')
    return true;

  return false;
}

function getMemory() {
  var mem;

  if (!process.memoryUsage)
    return {};

  mem = process.memoryUsage();

  return {
    rss: util.mb(mem.rss),
    jsHeap: util.mb(mem.heapUsed),
    jsHeapTotal: util.mb(mem.heapTotal),
    nativeHeap: util.mb(mem.rss - mem.heapTotal)
  };
}

/**
 * TimedCB
 * @constructor
 * @ignore
 */

function TimedCB(resolve, reject) {
  this.resolve = resolve;
  this.reject = reject;
  this.done = false;
}

TimedCB.wrap = function wrap(resolve, reject) {
  return new TimedCB(resolve, reject).start();
};

TimedCB.prototype.start = function start() {
  var self = this;
  var timeout;

  timeout = setTimeout(function() {
    self.cleanup(timeout);
    self.reject(new Error('Callback timed out.'));
  }, 5000);

  return function(err) {
    self.cleanup(timeout);
    if (err) {
      self.reject(err);
      return;
    }
    self.resolve();
  };
};

TimedCB.prototype.cleanup = function cleanup(timeout) {
  assert(!this.done);
  this.done = true;
  clearTimeout(timeout);
};

/*
 * Expose
 */

module.exports = HTTPServer;