Refactored some exchange code

lib/plugins/exchange/itbit/itbit.js

@@ -1,45 +0,0 @@
-const common = require('../../common/itbit')
-const coinUtils = require('../../../coin-utils')
-
-exports.buy = function (account, cryptoAtoms, fiatCode, cryptoCode) {
-  return trade('buy', account, cryptoAtoms, fiatCode, cryptoCode)
-}
-
-exports.sell = function (account, cryptoAtoms, fiatCode, cryptoCode) {
-  return trade('sell', account, cryptoAtoms, fiatCode, cryptoCode)
-}
-
-function trade (type, account, cryptoAtoms, fiatCode, cryptoCode) {
-  try {
-    const instrument = common.buildMarket(fiatCode, cryptoCode)
-    const cryptoAmount = coinUtils.toUnit(cryptoAtoms, cryptoCode)
-
-    return calculatePrice(type, instrument, cryptoAmount)
-      .then(price => {
-        const args = {
-          side: type,
-          type: 'limit',
-          currency: cryptoCode,
-          amount: cryptoAmount.toFixed(4),
-          price: price.toFixed(2),
-          instrument: instrument
-        }
-        return common.authRequest(account, 'POST', '/wallets/' + account.walletId + '/orders', args)
-      })
-  } catch (e) {
-    return Promise.reject(e)
-  }
-}
-
-function calculatePrice (type, tickerSymbol, amount) {
-  return common.request('GET', '/markets/' + tickerSymbol + '/order_book')
-    .then(orderBook => {
-      const book = type == 'buy' ? 'asks' : 'bids'
-      let collected = 0.0
-      for (const entry of orderBook[book]) {
-        collected += parseFloat(entry[1])
-        if (collected >= amount) return parseFloat(entry[0])
-      }
-      throw new Error('Insufficient market depth')
-    })
-}