index.js

'use strict';

var path                 = require('path')
  , fs                   = require('fs')
  , semver               = require('semver')
  , injectNodeGyp        = require('./lib/inject-node_gyp')
  , injectNodeExtensions = require('./lib/inject-node_extensions')
  , copyFileSync         = require('./lib/copy-file-sync')

var node_0_10         = semver.Range('>= 0.10.0 < 0.11')
  , node_greater_0_10 = semver.Range('>= 0.11.13')

function getFiles(nodeDir) {
  return  { node_gyp_file           : path.join(nodeDir, 'node.gyp')
          , node_extensions_h_file  : path.join(nodeDir, 'src', 'node_extensions.h')
          , node_extensions_cc_file : path.join(nodeDir, 'src', 'node_extensions.cc') }
}

function backup(file) {
  var copy = file + '.orig'
  if (!fs.existsSync(copy)) copyFileSync(file, copy);
}

function restore(file) {
  var copy = file + '.orig'
  if (fs.existsSync(copy)) copyFileSync(copy, file);
}

function inject_0_10(projectDir, nodeDir, cb) {
  var files = getFiles(nodeDir);

  backup(files.node_gyp_file)
  backup(files.node_extensions_h_file)
  backup(files.node_extensions_cc_file)

  injectNodeGyp(projectDir, nodeDir, onnodegyped);

  function onnodegyped(err, res) {
    if (err) return cb(err);

    injectNodeExtensions(
        files.node_extensions_h_file
      , files.node_extensions_cc_file
      , res.extensions
      , cb)
  }
}

function inject_greater_0_10(projectDir, nodeDir, cb) {
  var files = getFiles(nodeDir);

  backup(files.node_gyp_file)
  injectNodeGyp(projectDir, nodeDir, cb);
}

function restore_0_10(nodeDir) {
  var files = getFiles(nodeDir);
  restore(files.node_gyp_file)
  restore(files.node_extensions_h_file)
  restore(files.node_extensions_cc_file)
}

function restore_greater_0_10(nodeDir) {
  var files = getFiles(nodeDir);
  restore(files.node_gyp_file)
}

exports.inject = function inject(nodeVersion, projectDir, nodeDir, cb) {
  if (node_0_10.test(nodeVersion)) return inject_0_10(projectDir, nodeDir, cb);
  if (node_greater_0_10.test(nodeVersion)) return inject_greater_0_10(projectDir, nodeDir, cb);
  cb(new Error('nad only works for node 0.10 and greater'));
}

exports.restore = function restore(nodeVersion, nodeDir) {
  if (node_0_10.test(nodeVersion)) return restore_0_10(nodeDir);
  if (node_greater_0_10.test(nodeVersion)) return restore_greater_0_10(nodeDir);
  throw new Error('nad only works for node 0.10 and greater');
}

exports.injectNodeGyp = injectNodeGyp;
exports.injectNodeExtensions = injectNodeExtensions;