chore: refactor main code into smaller parts

lib/replyHandler.js

@@ -0,0 +1,78 @@
+'use strict'
+
+const Buffer = require('buffer').Buffer
+const utils = require('./utils')
+const pubsub = require('./pubsub')
+
+function onError (client, err) {
+  const commandObj = client.commandQueue.shift()
+  if (commandObj.error) {
+    err.stack = commandObj.error.stack.replace(/^Error.*?\n/, `ReplyError: ${err.message}\n`)
+  }
+  err.command = commandObj.command.toUpperCase()
+  if (commandObj.args && commandObj.args.length) {
+    err.args = commandObj.args
+  }
+
+  // Count down pub sub mode if in entering modus
+  if (client.pubSubMode > 1) {
+    client.pubSubMode--
+  }
+
+  const match = err.message.match(utils.errCode)
+  // LUA script could return user errors that don't behave like all other errors!
+  if (match) {
+    err.code = match[1]
+  }
+
+  commandObj.callback(err)
+}
+
+function normalReply (client, reply) {
+  const command = client.commandQueue.shift()
+  if (client._multi === false) {
+    reply = utils.handleReply(client, reply, command)
+  }
+  command.callback(null, reply)
+}
+
+function onResult (client, reply) {
+  // If in monitor mode, all normal commands are still working and we only want to emit the streamlined commands
+  // As this is not the average use case and monitor is expensive anyway, let's change the code here, to improve
+  // the average performance of all other commands in case of no monitor mode
+  if (client.monitoring) {
+    var replyStr
+    if (client.buffers && Buffer.isBuffer(reply)) {
+      replyStr = reply.toString()
+    } else {
+      replyStr = reply
+    }
+    // While reconnecting the redis server does not recognize the client as in monitor mode anymore
+    // Therefore the monitor command has to finish before it catches further commands
+    if (typeof replyStr === 'string' && utils.monitorRegex.test(replyStr)) {
+      const timestamp = replyStr.slice(0, replyStr.indexOf(' '))
+      const args = replyStr.slice(replyStr.indexOf('"') + 1, -1).split('" "').map((elem) => {
+        return elem.replace(/\\"/g, '"')
+      })
+      client.emit('monitor', timestamp, args, replyStr)
+      return
+    }
+  }
+  if (client.pubSubMode === 0) {
+    normalReply(client, reply)
+  } else if (client.pubSubMode !== 1) {
+    client.pubSubMode--
+    normalReply(client, reply)
+  } else if (!(reply instanceof Array) || reply.length <= 2) {
+    // Only PING and QUIT are allowed in this context besides the pub sub commands
+    // Ping replies with ['pong', null|value] and quit with 'OK'
+    normalReply(client, reply)
+  } else {
+    pubsub(client, reply)
+  }
+}
+
+module.exports = {
+  onError,
+  onResult
+}