/* global hexo */

'use strict';

const crypto = require('crypto');
const nextFont = require('./font');
const nextUrl = require('./next-url');

hexo.extend.helper.register('next_font', nextFont);
hexo.extend.helper.register('next_url', nextUrl);

hexo.extend.helper.register('next_inject', function(point) {
  return this.theme.injects[point]
    .map(item => this.partial(item.layout, item.locals, item.options))
    .join('');
});

hexo.extend.helper.register('next_js', function(file, pjax = false) {
  const { next_version } = this;
  const { internal } = this.theme.vendors;
  const minified_file = file.endsWith('.js') && !file.endsWith('.min.js') ? file.slice(0, -3) + '.min.js' : file;
  const links = {
    local   : this.url_for(`${this.theme.js}/${file}`),
    jsdelivr: `https://cdn.jsdelivr.net/npm/hexo-theme-next@${next_version}/source/js/${minified_file}`,
    unpkg   : `https://unpkg.com/hexo-theme-next@${next_version}/source/js/${file}`,
    cdnjs   : `https://cdnjs.cloudflare.com/ajax/libs/hexo-theme-next/${next_version}/${minified_file}`
  };
  const src = links[internal] || links.local;
  return `<script ${pjax ? 'data-pjax ' : ''}src="${src}"></script>`;
});

hexo.extend.helper.register('next_vendors', function(name) {
  const { url, integrity } = this.theme.vendors[name];
  const type = url.endsWith('css') ? 'css' : 'js';
  if (type === 'css') {
    if (integrity) return `<link rel="stylesheet" href="${url}" integrity="${integrity}" crossorigin="anonymous">`;
    return `<link rel="stylesheet" href="${url}">`;
  }
  if (integrity) return `<script src="${url}" integrity="${integrity}" crossorigin="anonymous"></script>`;
  return `<script src="${url}"></script>`;
});

hexo.extend.helper.register('next_data', function(name, ...data) {
  const json = data.length === 1 ? data[0] : Object.assign({}, ...data);
  return `<script class="next-config" data-name="${name}" type="application/json">${
    JSON.stringify(json).replace(/</g, '\\u003c')
  }</script>`;
});

hexo.extend.helper.register('next_pre', function() {
  const { preconnect } = this.theme;
  if (!preconnect) return '';
  const { enable, host } = this.theme.font;
  const { internal, plugins } = this.theme.vendors;
  const links = {
    local   : '',
    jsdelivr: 'https://cdn.jsdelivr.net',
    unpkg   : 'https://unpkg.com',
    cdnjs   : 'https://cdnjs.cloudflare.com'
  };
  const h = enable ? host || 'https://fonts.googleapis.com' : '';
  const i = links[internal];
  const p = links[plugins];
  const results = [...new Set([h, i, p].filter(origin => origin))].map(
    origin => `<link rel="preconnect" href="${origin}" crossorigin>`
  );
  return results.join('\n');
});

hexo.extend.helper.register('post_gallery', function(photos) {
  if (!photos || !photos.length) return '';
  const content = photos.map(photo => `
    <div class="post-gallery-image">
      <img src="${this.url_for(photo)}" itemprop="contentUrl">
    </div>`).join('');
  return `<div class="post-gallery" itemscope itemtype="http://schema.org/ImageGallery">
    ${content}
    </div>`;
});

hexo.extend.helper.register('post_edit', function(src) {
  const { post_edit } = this.theme;
  if (!post_edit.enable) return '';
  return this.next_url(post_edit.url + src, '<i class="fa fa-pen-nib"></i>', {
    class: 'post-edit-link',
    title: this.__('post.edit')
  });
});

hexo.extend.helper.register('gitalk_md5', function(path) {
  const str = this.url_for(path);
  return crypto.createHash('md5').update(str).digest('hex');
});

/**
 * Get page path given a certain language tag
 */
hexo.extend.helper.register('i18n_path', function(language) {
  const { path, lang } = this.page;
  const base = path.startsWith(lang) ? path.slice(lang.length + 1) : path;
  return this.url_for(`${this.languages.indexOf(language) === 0 ? '' : '/' + language}/${base}`);
});

/**
 * Get the language name
 */
hexo.extend.helper.register('language_name', function(language) {
  const name = hexo.theme.i18n.__(language)('name');
  return name === 'name' ? language : name;
});