install.js
function install() {
  if (!fs.existsSync(path.resolve(__dirname, 'vendor', 'pdfcrop_v0.4b', 'pdfcrop'))) {
    var url = 'http://downloads.sourceforge.net/project/pdfcrop/pdfcrop/PDFCrop%20v0.4b/pdfcrop_v0.4b.tar.gz'
    var write = targz().createWriteStream(path.resolve(__dirname, 'vendor'));
    var req = http.request(url, function(res) {
      res.pipe(write)
      write.on('finish', function(){
        console.log('pdfcrop installed')
      })
    })
  }

  if (process.platform == 'linux') {
    if (!spawnSync('apt-get', ['-v']).error) {
      console.log("apt-get install plotutils perl ghostscript plotutils pdf2svg")
      p = exec("apt-get install plotutils perl ghostscript plotutils pdf2svg")
      p.stderr.pipe(process.stderr)
      p.stdout.pipe(process.stdout)

    } else {
      console.log("sorry only apt-get supported right now for automatic install")
      console.log("You have to install the following packages:")
      console.log("  - perl")
      console.log("  - ghostscript")
      console.log("  - plotutils")
      console.log("  - pdf2svg")
    }
  } else if (process.platform == 'darwin') {
    if (!spawnSync('brew', ['-v']).error) {
      console.log("brew install plotutils perl ghostscript plotutils pdf2svg")
      p = exec("brew install plotutils perl ghostscript plotutils pdf2svg")
      p.stderr.pipe(process.stderr)
      p.stdout.pipe(process.stdout)
    } else {
      console.log("You have to install Homebrew from http://brew.sh first")
    }
  } else {
    console.log("Sorry, your system is not supported for automatic install")
    console.log("You have to install the following packages:")
    console.log("  - perl")
    console.log("  - ghostscript")
    console.log("  - plotutils")
    console.log("  - pdf2svg")
  }
}
function install() {
  if (!fs.existsSync(path.resolve(__dirname, 'vendor', 'pdfcrop_v0.4b', 'pdfcrop'))) {
    var url = 'http://downloads.sourceforge.net/project/pdfcrop/pdfcrop/PDFCrop%20v0.4b/pdfcrop_v0.4b.tar.gz'
    var write = targz().createWriteStream(path.resolve(__dirname, 'vendor'));
    var req = http.request(url, function(res) {
      res.pipe(write)
      write.on('finish', function(){
        console.log('pdfcrop installed')
      })
    })
  }

  if (process.platform == 'linux') {
    if (!spawnSync('apt-get', ['-v']).error) {
      console.log("apt-get install plotutils perl ghostscript plotutils pdf2svg")
      p = exec("apt-get install plotutils perl ghostscript plotutils pdf2svg")
      p.stderr.pipe(process.stderr)
      p.stdout.pipe(process.stdout)

    } else {
      console.log("sorry only apt-get supported right now for automatic install")
      console.log("You have to install the following packages:")
      console.log("  - perl")
      console.log("  - ghostscript")
      console.log("  - plotutils")
      console.log("  - pdf2svg")
    }
  } else if (process.platform == 'darwin') {
    if (!spawnSync('brew', ['-v']).error) {
      console.log("brew install plotutils perl ghostscript plotutils pdf2svg")
      p = exec("brew install plotutils perl ghostscript plotutils pdf2svg")
      p.stderr.pipe(process.stderr)
      p.stdout.pipe(process.stdout)
    } else {
      console.log("You have to install Homebrew from http://brew.sh first")
    }
  } else {
    console.log("Sorry, your system is not supported for automatic install")
    console.log("You have to install the following packages:")
    console.log("  - perl")
    console.log("  - ghostscript")
    console.log("  - plotutils")
    console.log("  - pdf2svg")
  }
}
/*
Press Command+Space and type Terminal and press enter/return key.
Run in Terminal app:
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)" < /dev/null 2> /dev/null
and press enter/return key. Wait for the command to finish.
Run:
brew install plotutils perl ghostscript