text: /*
   Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
   This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
   The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
   The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
   Code distributed by Google as part of the polymer project is also
   subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
   */
  
  'use strict';
  
  // Include Gulp & tools we'll use
  var gulp = require('gulp');
  var $ = require('gulp-load-plugins')();
  var del = require('del');
  var runSequence = require('run-sequence');
  var browserSync = require('browser-sync');
  var reload = browserSync.reload;
  var merge = require('merge-stream');
  var path = require('path');
  var fs = require('fs');
  var glob = require('glob-all');
  var historyApiFallback = require('connect-history-api-fallback');
  var packageJson = require('./package.json');
  var crypto = require('crypto');
  var ensureFiles = require('./tasks/ensure-files.js');
  
  // var ghPages = require('gulp-gh-pages');
  
  var AUTOPREFIXER_BROWSERS = [
    'ie >= 10',
    'ie_mob >= 10',
    'ff >= 30',
    'chrome >= 34',
    'safari >= 7',
    'opera >= 23',
    'ios >= 7',
    'android >= 4.4',
    'bb >= 10'
  ];
  
  var DIST = 'dist';
  
  var dist = function(subpath) {
    return !subpath ? DIST : path.join(DIST, subpath);
  };
  
  var styleTask = function(stylesPath, srcs) {
    return gulp.src(srcs.map(function(src) {
          return path.join('app', stylesPath, src);
        }))
        .pipe($.changed(stylesPath, {extension: '.css'}))
        .pipe($.autoprefixer(AUTOPREFIXER_BROWSERS))
        .pipe(gulp.dest('.tmp/' + stylesPath))
        .pipe($.minifyCss())
        .pipe(gulp.dest(dist(stylesPath)))
        .pipe($.size({title: stylesPath}));
  };
  
  var imageOptimizeTask = function(src, dest) {
    return gulp.src(src)
        .pipe($.imagemin({
          progressive: true,
          interlaced: true
        }))
        .pipe(gulp.dest(dest))
        .pipe($.size({title: 'images'}));
  };
  
  var optimizeHtmlTask = function(src, dest) {
    var assets = $.useref.assets({
      searchPath: ['.tmp', 'app']
    });
  
    return gulp.src(src)
        .pipe(assets)
        // Concatenate and minify JavaScript
        .pipe($.if('*.js', $.uglify({
          preserveComments: 'some'
        })))
        // Concatenate and minify styles
        // In case you are still using useref build blocks
        .pipe($.if('*.css', $.minifyCss()))
        .pipe(assets.restore())
        .pipe($.useref())
        // Minify any HTML
        .pipe($.if('*.html', $.minifyHtml({
          quotes: true,
          empty: true,
          spare: true
        })))
        // Output files
        .pipe(gulp.dest(dest))
        .pipe($.size({
          title: 'html'
        }));
  };
  
  // Compile and automatically prefix stylesheets
  gulp.task('styles', function() {
    return styleTask('styles', ['**/*.css']);
  });
  
  gulp.task('elements', function() {
    return styleTask('elements', ['**/*.css']);
  });
  
  // Ensure that we are not missing required files for the project
  // "dot" files are specifically tricky due to them being hidden on
  // some systems.
  gulp.task('ensureFiles', function(cb) {
    var requiredFiles = ['.jscsrc', '.jshintrc', '.bowerrc'];
  
    ensureFiles(requiredFiles.map(function(p) {
      return path.join(__dirname, p);
    }), cb);
  });
  
  // Lint JavaScript
  gulp.task('lint', ['ensureFiles'], function() {
    return gulp.src([
          'app/scripts/**/*.js',
          'app/elements/**/*.js',
          'app/elements/**/*.html',
          'gulpfile.js'
        ])
        .pipe(reload({
          stream: true,
          once: true
        }))
  
        // JSCS has not yet a extract option
        .pipe($.if('*.html', $.htmlExtract({strip: true})))
        .pipe($.jshint())
        .pipe($.jscs())
        .pipe($.jscsStylish.combineWithHintResults())
        .pipe($.jshint.reporter('jshint-stylish'))
        .pipe($.if(!browserSync.active, $.jshint.reporter('fail')));
  });
  
  // Optimize images
  gulp.task('images', function() {
    return imageOptimizeTask('app/images/**/*', dist('images'));
  });
  
  // Copy all files at the root level (app)
  gulp.task('copy', function() {
    var app = gulp.src([
      'app/*',
      '!app/test',
      '!app/elements',
      '!app/bower_components',
      '!app/cache-config.json',
      '!**/.DS_Store'
    ], {
      dot: true
    }).pipe(gulp.dest(dist()));
  
    // Copy over only the bower_components we need
    // These are things which cannot be vulcanized
    var bower = gulp.src([
      'app/bower_components/{webcomponentsjs,platinum-sw,sw-toolbox,promise-polyfill}/**/*'
    ]).pipe(gulp.dest(dist('bower_components')));
  
    return merge(app, bower)
        .pipe($.size({
          title: 'copy'
        }));
  });
  
  // Copy web fonts to dist
  gulp.task('fonts', function() {
    return gulp.src(['app/fonts/**'])
        .pipe(gulp.dest(dist('fonts')))
        .pipe($.size({
          title: 'fonts'
        }));
  });
  
  // Scan your HTML for assets & optimize them
  gulp.task('html', function() {
    return optimizeHtmlTask(
        ['app/**/*.html', '!app/{elements,test,bower_components}/**/*.html'],
        dist());
  });
  
  // Vulcanize granular configuration
  gulp.task('vulcanize', function() {
    return gulp.src('app/elements/elements.html')
        .pipe($.vulcanize({
          stripComments: true,
          inlineCss: true,
          inlineScripts: true
        }))
        .pipe(gulp.dest(dist('elements')))
        .pipe($.size({title: 'vulcanize'}));
  });
  
  // Generate config data for the <sw-precache-cache> element.
  // This include a list of files that should be precached, as well as a (hopefully unique) cache
  // id that ensure that multiple PSK projects don't share the same Cache Storage.
  // This task does not run by default, but if you are interested in using service worker caching
  // in your project, please enable it within the 'default' task.
  // See https://github.com/PolymerElements/polymer-starter-kit#enable-service-worker-support
  // for more context.
  gulp.task('cache-config', function(callback) {
    var dir = dist();
    var config = {
      cacheId: packageJson.name || path.basename(__dirname),
      disabled: false
    };
  
    glob([
          'index.html',
          './',
          'bower_components/webcomponentsjs/webcomponents-lite.min.js',
          '{elements,scripts,styles}/**/*.*'],
        {cwd: dir}, function(error, files) {
          if (error) {
            callback(error);
          } else {
            config.precache = files;
  
            var md5 = crypto.createHash('md5');
            md5.update(JSON.stringify(config.precache));
            config.precacheFingerprint = md5.digest('hex');
  
            var configPath = path.join(dir, 'cache-config.json');
            fs.writeFile(configPath, JSON.stringify(config), callback);
          }
        });
  });
  
  // Clean output directory
  gulp.task('clean', function(cb) {
    del(['.tmp', 'dist'], cb);
  });
  
  // Watch files for changes & reload
  gulp.task('serve', ['lint', 'styles', 'elements', 'images'], function() {
    browserSync({
      port: 3000,
      notify: false,
      logPrefix: 'PSK',
      snippetOptions: {
        rule: {
          match: '<span id="browser-sync-binding"></span>',
          fn: function(snippet) {
            return snippet;
          }
        }
      },
      // Run as an https by uncommenting 'https: true'
      // Note: this uses an unsigned certificate which on first access
      //       will present a certificate warning in the browser.
      // https: true,
      server: {
        baseDir: ['.tmp', 'app'],
        middleware: [historyApiFallback()],
        routes: {
          '/bower_components': 'bower_components'
        }
      }
    });
  
    gulp.watch(['app/**/*.html'], reload);
    gulp.watch(['app/styles/**/*.css'], ['styles', reload]);
    gulp.watch(['app/elements/**/*.css'], ['elements', reload]);
    gulp.watch(['app/{scripts,elements}/**/{*.js,*.html}'], ['lint']);
    gulp.watch(['app/images/**/*'], reload);
  });
  
  // Build and serve the output from the dist build
  gulp.task('serve:dist', ['default'], function() {
    browserSync({
      port: 3001,
      notify: false,
      logPrefix: 'PSK',
      snippetOptions: {
        rule: {
          match: '<span id="browser-sync-binding"></span>',
          fn: function(snippet) {
            return snippet;
          }
        }
      },
      // Run as an https by uncommenting 'https: true'
      // Note: this uses an unsigned certificate which on first access
      //       will present a certificate warning in the browser.
      // https: true,
      server: dist(),
      middleware: [historyApiFallback()]
    });
  });
  
  // Build production files, the default task
  gulp.task('default', ['clean'], function(cb) {
    // Uncomment 'cache-config' if you are going to use service workers.
    runSequence(
        ['copy', 'styles'],
        'elements',
        ['lint', 'images', 'fonts', 'html'],
        'vulcanize', // 'cache-config',
        cb);
  });
  
  // Load tasks for web-component-tester
  // Adds tasks for `gulp test:local` and `gulp test:remote`
  require('web-component-tester').gulp.init(gulp);
  
  // Load custom tasks from the `tasks` directory
  try {
    require('require-dir')('tasks');
  } catch (err) {
  }
  