/**
 *
 *  Material Design Lite
 *  Copyright 2015 Google Inc. All rights reserved.
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License
 *
 */

// jscs:disable jsDoc

'use strict';

// Include Gulp & Tools We'll Use
import fs from 'fs';
import path from 'path';
import mergeStream from 'merge-stream';
import del from 'del';
import vinylPaths from 'vinyl-paths';
import runSequence from 'run-sequence';
import browserSync from 'browser-sync';
import through from 'through2';
import swig from 'swig';
import gulp from 'gulp';
import closureCompiler from 'gulp-closure-compiler';
import gulpLoadPlugins from 'gulp-load-plugins';
import uniffe from './utils/uniffe.js';
import pkg from './package.json';

const $ = gulpLoadPlugins();
const reload = browserSync.reload;
const hostedLibsUrlPrefix = 'https://code.getmdl.io';
const templateArchivePrefix = 'mdl-template-';
const bucketProd = 'gs://www.getmdl.io';
const bucketStaging = 'gs://mdl-staging';
const bucketCode = 'gs://code.getmdl.io';
const banner = ['/**',
  ' * <%= pkg.name %> - <%= pkg.description %>',
  ' * @version v<%= pkg.version %>',
  ' * @license <%= pkg.license %>',
  ' * @copyright 2015 Google, Inc.',
  ' * @link https://github.com/google/material-design-lite',
  ' */',
  ''].join('\n');

let codeFiles = '';

const AUTOPREFIXER_BROWSERS = [
  'ie >= 10',
  'ie_mob >= 10',
  'ff >= 30',
  'chrome >= 34',
  'safari >= 7',
  'opera >= 23',
  'ios >= 7',
  'android >= 4.4',
  'bb >= 10'
];

const SOURCES = [
  // Component handler
  'src/mdlComponentHandler.js',
  // Polyfills/dependencies
  'src/third_party/**/*.js',
  // Base components
  'src/button/button.js',
  'src/checkbox/checkbox.js',
  'src/icon-toggle/icon-toggle.js',
  'src/menu/menu.js',
  'src/progress/progress.js',
  'src/radio/radio.js',
  'src/slider/slider.js',
  'src/snackbar/snackbar.js',
  'src/spinner/spinner.js',
  'src/switch/switch.js',
  'src/tabs/tabs.js',
  'src/textfield/textfield.js',
  'src/tooltip/tooltip.js',
  // Complex components (which reuse base components)
  'src/layout/layout.js',
  'src/data-table/data-table.js',
  // And finally, the ripples
  'src/ripple/ripple.js'
];

// ***** Development tasks ****** //

// Lint JavaScript
gulp.task('lint', () => {
  return gulp.src([
      'src/**/*.js',
      'gulpfile.babel.js'
    ])
    .pipe(reload({stream: true, once: true}))
    .pipe($.jshint())
    .pipe($.jscs())
    .pipe($.jshint.reporter('jshint-stylish'))
    .pipe($.jscs.reporter())
    .pipe($.if(!browserSync.active, $.jshint.reporter('fail')))
    .pipe($.if(!browserSync.active, $.jscs.reporter('fail')));
});

// ***** Production build tasks ****** //

// Optimize Images
// TODO: Update image paths in final CSS to match root/images
gulp.task('images', () => {
  return gulp.src('src/**/*.{svg,png,jpg}')
    .pipe($.flatten())
    .pipe($.cache($.imagemin({
      progressive: true,
      interlaced: true
    })))
    .pipe(gulp.dest('dist/images'))
    .pipe($.size({title: 'images'}));
});

// Compile and Automatically Prefix Stylesheets (dev)
gulp.task('styles:dev', () => {
  return gulp.src('src/**/*.scss')
    .pipe($.sass({
      precision: 10,
      onError: console.error.bind(console, 'Sass error:')
    }))
    .pipe($.cssInlineImages({
      webRoot: 'src'
    }))
    .pipe($.autoprefixer(AUTOPREFIXER_BROWSERS))
    .pipe(gulp.dest('.tmp/styles'))
    .pipe($.size({title: 'styles'}));
});

// Compile and Automatically Prefix Stylesheet Templates (production)
gulp.task('styletemplates', () => {
  // For best performance, don't add Sass partials to `gulp.src`
  return gulp.src('src/template.scss')
    // Generate Source Maps
    .pipe($.sourcemaps.init())
    .pipe($.sass({
      precision: 10,
      onError: console.error.bind(console, 'Sass error:')
    }))
    .pipe($.cssInlineImages({webRoot: 'src'}))
    .pipe($.autoprefixer(AUTOPREFIXER_BROWSERS))
    .pipe(gulp.dest('.tmp'))
    // Concatenate Styles
    .pipe($.concat('material.css.template'))
    .pipe(gulp.dest('dist'))
    // Minify Styles
    .pipe($.if('*.css.template', $.csso()))
    .pipe($.concat('material.min.css.template'))
    .pipe($.header(banner, {pkg}))
    .pipe($.sourcemaps.write('.'))
    .pipe(gulp.dest('dist'))
    .pipe($.size({title: 'styles'}));
});

// Compile and Automatically Prefix Stylesheets (production)
gulp.task('styles', () => {
  // For best performance, don't add Sass partials to `gulp.src`
  return gulp.src('src/material-design-lite.scss')
    // Generate Source Maps
    .pipe($.sourcemaps.init())
    .pipe($.sass({
      precision: 10,
      onError: console.error.bind(console, 'Sass error:')
    }))
    .pipe($.cssInlineImages({webRoot: 'src'}))
    .pipe($.autoprefixer(AUTOPREFIXER_BROWSERS))
    .pipe(gulp.dest('.tmp'))
    // Concatenate Styles
    .pipe($.concat('material.css'))
    .pipe($.header(banner, {pkg}))
    .pipe(gulp.dest('dist'))
    // Minify Styles
    .pipe($.if('*.css', $.csso()))
    .pipe($.concat('material.min.css'))
    .pipe($.header(banner, {pkg}))
    .pipe($.sourcemaps.write('.'))
    .pipe(gulp.dest('dist'))
    .pipe($.size({title: 'styles'}));
});

// Only generate CSS styles for the MDL grid
gulp.task('styles-grid', () => {
  return gulp.src('src/material-design-lite-grid.scss')
    .pipe($.sass({
      precision: 10,
      onError: console.error.bind(console, 'Sass error:')
    }))
    .pipe($.autoprefixer(AUTOPREFIXER_BROWSERS))
    .pipe(gulp.dest('.tmp'))
    // Concatenate Styles
    .pipe($.concat('material-grid.css'))
    .pipe($.header(banner, {pkg}))
    .pipe(gulp.dest('dist'))
    // Minify Styles
    .pipe($.if('*.css', $.csso()))
    .pipe($.concat('material-grid.min.css'))
    .pipe($.header(banner, {pkg}))
    .pipe(gulp.dest('dist'))
    .pipe($.size({title: 'styles-grid'}));
});

// Build with Google's Closure Compiler, requires Java 1.7+ installed.
gulp.task('closure', () => {
  return gulp.src(SOURCES)
    .pipe(closureCompiler({
      compilerPath: 'node_modules/google-closure-compiler/compiler.jar',
      fileName: 'material.closure.min.js',
      compilerFlags: {
        // jscs:disable requireCamelCaseOrUpperCaseIdentifiers
        compilation_level: 'ADVANCED_OPTIMIZATIONS',
        language_in: 'ECMASCRIPT6_STRICT',
        language_out: 'ECMASCRIPT5_STRICT',
        warning_level: 'VERBOSE'
        // jscs:enable requireCamelCaseOrUpperCaseIdentifiers
      }
    }))
    .pipe(gulp.dest('./dist'));
});

// Concatenate And Minify JavaScript
gulp.task('scripts', ['lint'], () => {
  return gulp.src(SOURCES)
    .pipe($.if(/mdlComponentHandler\.js/, $.util.noop(), uniffe()))
    .pipe($.sourcemaps.init())
    // Concatenate Scripts
    .pipe($.concat('material.js'))
    .pipe($.iife({useStrict: true}))
    .pipe(gulp.dest('dist'))
    // Minify Scripts
    .pipe($.uglify({
      sourceRoot: '.',
      sourceMapIncludeSources: true
    }))
    .pipe($.header(banner, {pkg}))
    .pipe($.concat('material.min.js'))
    // Write Source Maps
    .pipe($.sourcemaps.write('.'))
    .pipe(gulp.dest('dist'))
    .pipe($.size({title: 'scripts'}));
});

// Clean Output Directory
gulp.task('clean', () => del(['dist', '.publish']));

// Copy package manger and LICENSE files to dist
gulp.task('metadata', () => {
  return gulp.src([
      'package.json',
      'bower.json',
      'LICENSE'
    ])
    .pipe(gulp.dest('dist'));
});

// Build Production Files, the Default Task
gulp.task('default', ['clean'], cb => {
  runSequence(
    ['styles', 'styles-grid'],
    ['scripts'],
    ['mocha'],
    cb);
});

// Build production files and microsite
gulp.task('all', ['clean'], cb => {
  runSequence(
    ['styletemplates'],
    ['styles-grid', 'styles:gen'],
    ['scripts'],
    ['mocha'],
    ['assets', 'pages',
     'templates', 'images', 'metadata'],
    ['zip'],
    cb);
});

// ***** Testing tasks ***** //

gulp.task('mocha', ['styles'], () => {
  return gulp.src('test/index.html')
    .pipe($.mochaPhantomjs({reporter: 'tap'}));
});

gulp.task('mocha:closure', ['closure'], () => {
  return gulp.src('test/index.html')
    .pipe($.replace('src="../dist/material.js"',
        'src="../dist/material.closure.min.js"'))
    .pipe($.rename('temp.html'))
    .pipe(gulp.dest('test'))
    .pipe($.mochaPhantomjs({reporter: 'tap'}))
    .on('finish', () => del.sync('test/temp.html'))
    .on('error', () => del.sync('test/temp.html'));
});

gulp.task('test', [
  'lint',
  'mocha',
  'mocha:closure'
]);

gulp.task('test:visual', () => {
  browserSync({
    notify: false,
    server: '.',
    startPath: 'test/visual/index.html'
  });

  gulp.watch('test/visual/**', reload);
});

// ***** Landing page tasks ***** //

/**
 * Site metadata for use with templates.
 * @type {Object}
 */
const site = {};

/**
 * Generates an HTML file based on a template and file metadata.
 */
function applyTemplate() {
  return through.obj((file, enc, cb) => {
    const data = {
      site,
      page: file.page,
      content: file.contents.toString()
    };

    const templateFile = path.join(
        __dirname, 'docs', '_templates', `${file.page.layout}.html`);
    const tpl = swig.compileFile(templateFile, {cache: false});

    file.contents = new Buffer(tpl(data));
    cb(null, file);
  });
}

/**
 * Generates an index.html file for each README in MDL/src directory.
 */
gulp.task('components', ['demos'], () => {
  return gulp.src('src/**/README.md', {base: 'src'})
    // Add basic front matter.
    .pipe($.header('---\nlayout: component\nbodyclass: component\ninclude_prefix: ../../\n---\n\n'))
    .pipe($.frontMatter({
      property: 'page',
      remove: true
    }))
    .pipe($.marked())
    .pipe((() => {
      return through.obj((file, enc, cb) => {
        file.page.component = file.relative.split('/')[0];
        cb(null, file);
      });
    })())
    .pipe(applyTemplate())
    .pipe($.rename(path => path.basename = 'index'))
    .pipe(gulp.dest('dist/components'));
});

/**
 * Copies demo files from MDL/src directory.
 */
gulp.task('demoresources', () => {
  return gulp.src([
      'src/**/demos.css',
      'src/**/demo.css',
      'src/**/demo.js'
    ], {base: 'src'})
    .pipe($.if('*.scss', $.sass({
      precision: 10,
      onError: console.error.bind(console, 'Sass error:')
    })))
    .pipe($.cssInlineImages({webRoot: 'src'}))
    .pipe($.if('*.css', $.autoprefixer(AUTOPREFIXER_BROWSERS)))
    .pipe(gulp.dest('dist/components'));
});

/**
 * Generates demo files for testing made of all the snippets and the demo file
 * put together.
 */
gulp.task('demos', ['demoresources'], () => {
  /**
   * Retrieves the list of component folders.
   */
  function getComponentFolders() {
    return fs.readdirSync('src')
      .filter(file => fs.statSync(path.join('src', file)).isDirectory());
  }

  const tasks = getComponentFolders().map(component => {
    return gulp.src([
        path.join('src', component, 'snippets', '*.html'),
        path.join('src', component, 'demo.html')
      ])
      .pipe($.concat('/demo.html'))
      // Add basic front matter.
      .pipe($.header('---\nlayout: demo\nbodyclass: demo\ninclude_prefix: ../../\n---\n\n'))
      .pipe($.frontMatter({
        property: 'page',
        remove: true
      }))
      .pipe($.marked())
      .pipe((() => {
        return through.obj((file, enc, cb) => {
          file.page.component = component;
          cb(null, file);
        });
      })())
      .pipe(applyTemplate())
      .pipe(gulp.dest(path.join('dist', 'components', component)));
  });

  return mergeStream(tasks);
});

/**
 * Generates an HTML file for each md file in _pages directory.
 */
gulp.task('pages', ['components'], () => {
  return gulp.src('docs/_pages/*.md')
    .pipe($.frontMatter({
      property: 'page',
      remove: true
    }))
    .pipe($.marked())
    .pipe(applyTemplate())
    .pipe($.replace('$$version$$', pkg.version))
    .pipe($.replace('$$hosted_libs_prefix$$', hostedLibsUrlPrefix))
    .pipe($.replace('$$template_archive_prefix$$', templateArchivePrefix))
    /* Replacing code blocks class name to match Prism's. */
    .pipe($.replace('class="lang-', 'class="language-'))
    /* Translate html code blocks to "markup" because that's what Prism uses. */
    .pipe($.replace('class="language-html', 'class="language-markup'))
    .pipe($.rename(path => {
      if (path.basename !== 'index') {
        path.dirname = path.basename;
        path.basename = 'index';
      }
    }))
    .pipe(gulp.dest('dist'));
});

/**
 * Copies assets from MDL and _assets directory.
 */
gulp.task('assets', () => {
  return gulp.src([
      'docs/_assets/**/*',
      'node_modules/clippy/build/clippy.swf',
      'node_modules/swfobject-npm/swfobject/src/swfobject.js',
      'node_modules/prismjs/prism.js',
      'node_modules/prismjs/components/prism-markup.min.js',
      'node_modules/prismjs/components/prism-javascript.min.js',
      'node_modules/prismjs/components/prism-css.min.js',
      'node_modules/prismjs/components/prism-bash.min.js',
      'node_modules/prismjs/dist/prism-default/prism-default.css'
    ])
    .pipe($.if(/\.js/i, $.replace('$$version$$', pkg.version)))
    .pipe($.if(/\.js/i, $.replace('$$hosted_libs_prefix$$', hostedLibsUrlPrefix)))
    .pipe($.if(/\.(svg|jpg|png)$/i, $.imagemin({
      progressive: true,
      interlaced: true
    })))
    .pipe($.if(/\.css/i, $.autoprefixer(AUTOPREFIXER_BROWSERS)))
    .pipe($.if(/\.css/i, $.csso()))
    .pipe($.if(/\.js/i, $.uglify({
      preserveComments: 'some',
      sourceRoot: '.',
      sourceMapIncludeSources: true
    })))
    .pipe(gulp.dest('dist/assets'));
});

/**
 * Defines the list of resources to watch for changes.
 */
function watch() {
  gulp.watch(['src/**/*.js', '!src/**/README.md'],
    ['scripts', 'demos', 'components', reload]);
  gulp.watch(['src/**/*.{scss,css}'],
    ['styles', 'styles-grid', 'styletemplates', reload]);
  gulp.watch(['src/**/*.html'], ['pages', reload]);
  gulp.watch(['src/**/*.{svg,png,jpg}'], ['images', reload]);
  gulp.watch(['src/**/README.md'], ['pages', reload]);
  gulp.watch(['templates/**/*'], ['templates', reload]);
  gulp.watch(['docs/**/*'], ['pages', 'assets', reload]);
  gulp.watch(['package.json', 'bower.json', 'LICENSE'], ['metadata']);
}

/**
 * Serves the landing page from "out" directory.
 */
gulp.task('serve:browsersync', () => {
  browserSync({
    notify: false,
    server: {
      baseDir: ['dist']
    }
  });

  watch();
});

gulp.task('serve', () => {
  $.connect.server({
    root: 'dist',
    port: 5000,
    livereload: true
  });

  watch();

  gulp.src('dist/index.html')
    .pipe($.open({uri: 'http://localhost:5000'}));
});

// Generate release archive containing just JS, CSS, Source Map deps
gulp.task('zip:mdl', () => {
  return gulp.src([
      'dist/material?(.min)@(.js|.css)?(.map)',
      'LICENSE',
      'bower.json',
      'package.json'
    ])
    .pipe($.zip('mdl.zip'))
    .pipe(gulp.dest('dist'));
});

/**
 * Returns the list of children directories inside the given directory.
 * @param {string} dir the parent directory
 * @return {Array<string>} list of child directories
 */
function getSubDirectories(dir) {
  return fs.readdirSync(dir)
    .filter(file => fs.statSync(path.join(dir, file)).isDirectory());
}

// Generate release archives containing the templates and assets for templates.
gulp.task('zip:templates', () => {
  const templates = getSubDirectories('dist/templates');

  // Generate a zip file for each template.
  const generateZips = templates.map(template => {
    return gulp.src([
        `dist/templates/${template}/**/*.*`,
        'LICENSE'
      ])
      .pipe($.rename(path => {
        path.dirname = path.dirname.replace(`dist/templates/${template}`, '');
      }))
      .pipe($.zip(`${templateArchivePrefix}${template}.zip`))
      .pipe(gulp.dest('dist'));
  });

  return mergeStream(generateZips);
});

gulp.task('zip', [
  'zip:templates',
  'zip:mdl'
]);

gulp.task('genCodeFiles', () => {
  return gulp.src([
      'dist/material.*@(js|css)?(.map)',
      'dist/mdl.zip',
      `dist/${templateArchivePrefix}*.zip`
    ], {read: false})
    .pipe($.tap(file => {
      codeFiles += ` dist/${path.basename(file.path)}`;
    }));
});

// Push the latest version of code resources (CSS+JS) to Google Cloud Storage.
// Public-read objects in GCS are served by a Google provided and supported
// global, high performance caching/content delivery network (CDN) service.
// This task requires gsutil to be installed and configured.
// For info on gsutil: https://cloud.google.com/storage/docs/gsutil.
gulp.task('pushCodeFiles', () => {
  const dest = bucketCode;
  console.log(`Publishing ${pkg.version} to CDN (${dest})`);

  // Build cache control and gsutil cmd to copy
  // each object into a GCS bucket. The dest is a version specific path.
  // The gsutil -m option requests parallel copies.
  // The gsutil -h option is used to set metadata headers
  // (cache control, in this case).
  // Code files should NEVER be touched after uploading, therefore
  // 30 days caching is a safe value.
  const cacheControl = '-h "Cache-Control:public,max-age=2592000"';
  const gsutilCpCmd = 'gsutil -m cp -z js,css,map ';
  const gsutilCacheCmd = `gsutil -m setmeta -R ${cacheControl}`;

  // Upload the goodies to a separate GCS bucket with versioning.
  // Using a sep bucket avoids the risk of accidentally blowing away
  // old versions in the microsite bucket.
  return gulp.src('')
    .pipe($.shell([
      `${gsutilCpCmd}${codeFiles} ${dest}/${pkg.version}`,
      `${gsutilCacheCmd} ${dest}/${pkg.version}`
    ]));
});

gulp.task('publish:code', cb => {
  runSequence(
    ['zip:mdl', 'zip:templates'],
    'genCodeFiles',
    'pushCodeFiles',
    cb);
});

/**
 * Function to publish staging or prod version from local tree,
 * or to promote staging to prod, per passed arg.
 * @param {string} pubScope the scope to publish to.
 */
function mdlPublish(pubScope) {
  let cacheTtl = null;
  let src = null;
  let dest = null;

  if (pubScope === 'staging') {
    // Set staging specific vars here.
    cacheTtl = 0;
    src = 'dist/*';
    dest = bucketStaging;
  } else if (pubScope === 'prod') {
    // Set prod specific vars here.
    cacheTtl = 60;
    src = 'dist/*';
    dest = bucketProd;
  } else if (pubScope === 'promote') {
    // Set promote (essentially prod) specific vars here.
    cacheTtl = 60;
    src = `${bucketStaging}/*`;
    dest = bucketProd;
  }

  let infoMsg = `Publishing ${pubScope}/${pkg.version} to GCS (${dest})`;
  if (src) {
    infoMsg += ` from ${src}`;
  }
  console.log(infoMsg);

  // Build gsutil commands:
  // The gsutil -h option is used to set metadata headers.
  // The gsutil -m option requests parallel copies.
  // The gsutil -R option is used for recursive file copy.
  const cacheControl = `-h "Cache-Control:public,max-age=${cacheTtl}"`;
  const gsutilCacheCmd = `gsutil -m setmeta ${cacheControl} ${dest}/**`;
  const gsutilCpCmd = `gsutil -m cp -r -z html,css,js,svg ${src} ${dest}`;

  gulp.src('').pipe($.shell([gsutilCpCmd, gsutilCacheCmd]));
}

// Push the local build of the MDL microsite and release artifacts to the
// production Google Cloud Storage bucket for general serving to the web.
// Public-read objects in GCS are served by a Google provided and supported
// global, high performance caching/content delivery network (CDN) service.
// This task requires gsutil to be installed and configured.
// For info on gsutil: https://cloud.google.com/storage/docs/gsutil.
//
gulp.task('publish:prod', () => {
  mdlPublish('prod');
});

// Promote the staging version of the MDL microsite and release artifacts
// to the production Google Cloud Storage bucket for general serving.
// Public-read objects in GCS are served by a Google provided and supported
// global, high performance caching/content delivery network (CDN) service.
// This task requires gsutil to be installed and configured.
// For info on gsutil: https://cloud.google.com/storage/docs/gsutil.
//
gulp.task('publish:promote', () => {
  mdlPublish('promote');
});

// Push the staged version of the MDL microsite and release artifacts
// to a production Google Cloud Storage bucket for staging and pre-production testing.
//
// This task requires gsutil to be installed and configured.
// For info on gsutil: https://cloud.google.com/storage/docs/gsutil.
//
gulp.task('publish:staging', () => {
  mdlPublish('staging');
});

gulp.task('_release', () => {
  return gulp.src([
      'dist/material?(.min)@(.js|.css)?(.map)',
      'LICENSE',
      'README.md',
      'bower.json',
      'package.json',
      '.jscsrc',
      '.jshintrc',
      './sr?/**/*',
      'gulpfile.babel.js',
      './util?/**/*'
    ])
    .pipe(gulp.dest('_release'));
});

gulp.task('publish:release', ['_release'], () => {
  return gulp.src('_release')
    .pipe($.subtree({
      remote: 'origin',
      branch: 'release'
    }))
    .pipe(vinylPaths(del));
});

gulp.task('templates:styles', () => {
  return gulp.src('templates/**/*.css')
    .pipe($.autoprefixer(AUTOPREFIXER_BROWSERS))
    // FIXME: This crashes. It's a bug in gulp-csso,
    // not csso itself.
    //.pipe($.csso())
    .pipe(gulp.dest('dist/templates'));
});

gulp.task('templates:static', () => {
  return gulp.src('templates/**/*.html')
  .pipe($.replace('$$version$$', pkg.version))
  .pipe($.replace('$$hosted_libs_prefix$$', hostedLibsUrlPrefix))
  .pipe(gulp.dest('dist/templates'));
});

// This task can be used if you want to test the templates against locally
// built version of the MDL libraries.
gulp.task('templates:localtestingoverride', () => {
  return gulp.src('templates/**/*.html')
    .pipe($.replace('$$version$$', '.'))
    .pipe($.replace('$$hosted_libs_prefix$$', ''))
    .pipe(gulp.dest('dist/templates'));
});

gulp.task('templates:images', () => {
  return gulp.src('templates/*/images/**/*')
    .pipe($.imagemin({
      progressive: true,
      interlaced: true
    }))
    .pipe(gulp.dest('dist/templates'));
});

gulp.task('templates:fonts', () => {
  return gulp.src('templates/*/fonts/**/*')
    .pipe(gulp.dest('dist/templates/'));
});

gulp.task('templates', [
  'templates:static',
  'templates:images',
  'templates:fonts',
  'templates:styles'
]);

gulp.task('styles:gen', ['styles'], () => {
  const MaterialCustomizer = require('./docs/_assets/customizer.js');
  const templatePath = path.join(__dirname, 'dist', 'material.min.css.template');
  // TODO: This task needs refactoring once we turn MaterialCustomizer
  // into a proper Node module.
  const mc = new MaterialCustomizer();
  mc.template = fs.readFileSync(templatePath).toString();

  let stream = gulp.src('');

  mc.paletteIndices.forEach(primary => {
    mc.paletteIndices.forEach(accent => {
      if (primary === accent) {
        return;
      }

      if (mc.forbiddenAccents.indexOf(accent) !== -1) {
        return;
      }

      const primaryName = primary.toLowerCase().replace(' ', '_');
      const accentName = accent.toLowerCase().replace(' ', '_');

      stream = stream.pipe($.file(
        `material.${primaryName}-${accentName}.min.css`,
        mc.processTemplate(primary, accent)
      ));
    });
  });

  stream.pipe(gulp.dest('dist'));
});