snmp = require('snmp-native')

snmpTypes = require('./snmp-types').snmpTypes

typeStr = require('./snmp-types').typeStr

###

Converts TimeTicks value to easy-to-use structure.

###

convertTimeTicks = (v) ->

  intDiv = (a, b) -> Math.floor(a / b)

  msec = v % 100

  v = intDiv(v, 100)

  secs = v % 60

  v = intDiv(v, 60)

  mins = v % 60

  v = intDiv(v, 60)

  hours = v % 24

  days = intDiv(v, 24)

  days: days

  hours: hours

  mins: mins

  secs: secs

  msecs: msec

###

Processes SNMP result value.

###

processVarBind = (vb) ->

  rv =

    oid: "." + vb.oid.reduce (x,y) -> x+"."+y

    value: vb.value

    type: vb.type

    typeStr: typeStr[vb.type] ? 'Unknown'

    ts: Date.now() / 1000

  if (rv.type == snmpTypes.TimeTicks)

    rv.timeTicks = convertTimeTicks(vb.value)

  rv

###

Creates SNMP session and retrieves values for the supplied OIDs.

###

snmpget = (opts, cb) ->

  sess = new snmp.Session(opts)

  res = []

  snmpgetOne = (i) ->

    if (i < opts.oids.length)

      oid = opts.oids[i]

      sess.get({oid: oid}, (err, vbs) ->

        if (err)

          res.push { error: err, oid: oid }

          if (opts.abortOnError)

            i = opts.oids.length

        else

          res.push vbs.map(processVarBind)...

        snmpgetOne ++i

      )

    else

      sess.close()

      cb(res)

  snmpgetOne 0

exports.snmpget = snmpget