/*!
 * Bootstrap Grunt task for generating npm-shrinkwrap.canonical.json
 * http://getbootstrap.com
 * Copyright 2014 Twitter, Inc.
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
 */
/*
This Grunt task updates the npm-shrinkwrap.canonical.json file that's used as the key for Bootstrap's npm packages cache.
This task should be run and the updated file should be committed whenever Bootstrap's dependencies change.
*/
'use strict';
var canonicallyJsonStringify = require('canonical-json');
var NON_CANONICAL_FILE = 'npm-shrinkwrap.json';
var DEST_FILE = 'test-infra/npm-shrinkwrap.canonical.json';


function cleanup(shrinkwrap) {
  // Remove `resolved` property to avoid irrelevant changes
  // See https://github.com/npm/npm/issues/3581
  if (typeof shrinkwrap === 'string') {
    return shrinkwrap;
  }
  delete shrinkwrap.resolved;
  for (var key in shrinkwrap) {
    shrinkwrap[key] = cleanup(shrinkwrap[key]);
  }
  return shrinkwrap;
}

function updateShrinkwrap(grunt) {
  // Assumption: Non-canonical shrinkwrap already generated by prerequisite Grunt task
  var shrinkwrapData = grunt.file.readJSON(NON_CANONICAL_FILE);
  grunt.log.writeln('Deleting ' + NON_CANONICAL_FILE.cyan + '...');
  grunt.file.delete(NON_CANONICAL_FILE);
  // Output as Canonical JSON in correct location
  grunt.file.write(DEST_FILE, canonicallyJsonStringify(cleanup(shrinkwrapData)));
  grunt.log.writeln('File ' + DEST_FILE.cyan + ' updated.');
}


module.exports = updateShrinkwrap;
