'use strict'

var flatstr = require('flatstr')
var format = require('quick-format-unescaped')
var util = require('util')
var pid = process.pid
var os = require('os')
var hostname = os.hostname()
var baseLog = flatstr('{"pid":' + pid + ',"hostname":"' + hostname + '",')
var levels = require('./levels')
var serializers = require('./serializers')
var time = require('./time')

function noop () {}

function copy (a, b) {
  for (var k in b) { a[k] = b[k] }
  return a
}

// Must be invoked via .call() to retain speed of inlining into the
// Pino constructor.
function applyOptions (opts) {
  this.serializers = opts.serializers
  this.stringify = opts.stringify
  this.end = opts.end
  this.name = opts.name
  this.timestamp = opts.timestamp
  this.slowtime = opts.slowtime
  this.chindings = opts.chindings
  this.cache = opts.cache
  this.formatOpts = opts.formatOpts
  this.onTerminated = opts.onTerminated
  this.messageKey = opts.messageKey
  this.messageKeyString = opts.messageKeyString

  if (opts.level && opts.levelVal) {
    var levelIsStandard = levels.isStandardLevel(opts.level)
    var valIsStandard = levels.isStandardLevelVal(opts.levelVal)
    if (valIsStandard) throw Error('level value is already used: ' + opts.levelVal)
    if (levelIsStandard === false && valIsStandard === false) this.addLevel(opts.level, opts.levelVal)
  }
  this._setLevel(opts.level)
  this._baseLog = flatstr(baseLog +
    (this.name === undefined ? '' : '"name":' + this.stringify(this.name) + ','))

  if (opts.timestamp === false) {
    this.time = time.getNoTime
  } else if (opts.slowtime) {
    this.time = time.getSlowTime
  } else {
    this.time = time.getTime
  }
}

function defineLevelsProperty (onObject) {
  Object.defineProperty(onObject, 'levels', {
    value: {
      values: copy({}, levels.levels),
      labels: copy({}, levels.nums)
    },
    enumerable: true
  })
  Object.defineProperty(onObject.levels.values, 'silent', {value: Infinity})
  Object.defineProperty(onObject.levels.labels, Infinity, {value: 'silent'})
}

function streamIsBlockable (s) {
  if (s.hasOwnProperty('_handle') && s._handle.hasOwnProperty('fd') && s._handle.fd) return true
  if (s.hasOwnProperty('fd') && s.fd) return true
  return false
}

function countInterp (s, i) {
  var n = 0
  var pos = 0
  while (true) {
    pos = s.indexOf(i, pos)
    if (pos >= 0) {
      ++n
      pos += 2
    } else break
  }
  return n
}

function genLog (z) {
  return function LOG (a, b, c, d, e, f, g, h, i, j, k) {
    var l = 0
    var m = null
    var n = null
    var o
    var p
    if (typeof a === 'object' && a !== null) {
      m = a
      n = [b, c, d, e, f, g, h, i, j, k]
      l = 1

      if (m.method && m.headers && m.socket) {
        m = serializers.mapHttpRequest(m)
      } else if (typeof m.setHeader === 'function') {
        m = serializers.mapHttpResponse(m)
      }
    } else {
      n = [a, b, c, d, e, f, g, h, i, j, k]
    }
    p = n.length = arguments.length - l
    if (p > 1) {
      l = typeof a === 'string' ? countInterp(a, '%j') : 0
      if (l) {
        n.length = l + countInterp(a, '%d') + countInterp(a, '%s') + 1
        o = `${util.format.apply(null, n)}`
      } else {
        o = format(n, this.formatOpts)
      }
    } else if (p) {
      o = n[0]
    }
    this.write(m, o, z)
  }
}

module.exports = {
  noop: noop,
  copy: copy,
  applyOptions: applyOptions,
  defineLevelsProperty: defineLevelsProperty,
  streamIsBlockable: streamIsBlockable,
  genLog: genLog
}