prey/prey-node-client

"use strict";

var fs = require('fs'),
    exec = require('child_process').exec,
    _ = require('underscore');

var battery_fallback = function(callback) {

  var battery_path = '/proc/acpi/battery/BAT0',
      cmd  ='cat ' + battery_path + '/state';

  let exists = fs.existsSync(battery_path)
  if (!exists) return callback(new Error(battery_path + ' not found.'));

  exec(cmd, function(err, stdout) {
    if (err) return callback(err);

    var output = stdout.toString(),
        remaining = output.match(/remaining capacity:\s+(\d+)/)[1],
        state = output.match(/charging state:\s+(\w+)/)[1],
        cmdInfo = 'cat ' + battery_path + '/info';

    exec(cmdInfo, function(err, stdout){
      if(err) return callback(err);

      var full = stdout.toString().match(/last full capacity:\s+(\d+)/)[1];

      var data = {
        percentage_remaining: parseInt(remaining) * 100 / parseInt(full),
        time_remaining: null, // TODO
        state: state.toLowerCase()
      };

      callback(null, data);
    });
  });
};

/**
 * Try upower, then fallback to /proc/acpi if upower does not exist.
 **/
exports.get_battery_status = function(callback){

  var cmd = 'upower --dump';

  exec(cmd, function(err, stdout) {
    if (err) {
      if (err.code === 127) { // command not found
        return battery_fallback(callback);
      } else {
        return callback(err);
      }
    }

    var obj = _.chain(stdout.split('\n\n'))
      .map(function(block) {
      return block.split('\n');
    }).filter(function(blockarray) {
      return blockarray[0].match(/battery_BAT/);
    })
    .flatten()
    .reduce(function(o, el) {
      var m = el.match(/(percentage|state):\s+(\S+)/);
      if (m) {
        if (m[1] === "percentage")
          o.percentage_remaining = m[2].replace(/\%/g, '');
        else
          o[m[1]] = m[2].toLowerCase(); // o.state =
      }
      return o;
    }, {time_remaining: null}).value();

    if (obj.state)
      callback(null, obj)
    else
      callback(new Error('Unable to read battery info.'))

  });

};

exports.get_remaining_storage = function(callback) {

  exec("df -kh / | tail -1", function(err, stdout){
    if (err) return callback(err);

    var data = stdout.toString().trim().split(/\s+/);

    var info = {
      total_gb: data[1],
      free_gb : data[3],
      used    : data[4]
    };

    callback(null, info);
  });
};