Lewerow/Zurvan

'use strict';
var assert = require('assert');
var FieldOverrider = require('./utils/FieldOverrider');
var TimeUnit = require('../TimeUnit');

function ProcessTimerInterceptor(timeServer) {
  this.timeServer = timeServer;
}

ProcessTimerInterceptor.prototype.intercept = function() {
  this.uptimeOverrider = new FieldOverrider(
    process,
    'uptime',
    this.uptime.bind(this)
  );
  this.hrtimeOverrider = new FieldOverrider(
    process,
    'hrtime',
    this.hrtime.bind(this)
  );
};

ProcessTimerInterceptor.prototype.release = function() {
  var currentProcessTime = process.hrtime();
  this.uptimeOverrider.restore();
  this.hrtimeOverrider.restore();
  return currentProcessTime;
};

ProcessTimerInterceptor.prototype.uptime = function() {
  return this.timeServer.currentTime.toSeconds();
};

function toHrtimeFormat(time) {
  return [
    Math.floor(time.toSeconds()),
    time.toNanoseconds() %
      (TimeUnit.seconds.coefficient / TimeUnit.nanoseconds.coefficient)
  ];
}

ProcessTimerInterceptor.prototype.hrtime = function(previousValue) {
  if (previousValue !== undefined) {
    assert(previousValue.length === 2);
    var previousTime = TimeUnit.seconds(previousValue[0]).extended(
      TimeUnit.nanoseconds(previousValue[1])
    );
    return toHrtimeFormat(this.timeServer.currentTime.shortened(previousTime));
  }

  return toHrtimeFormat(this.timeServer.currentTime);
};

module.exports = ProcessTimerInterceptor;