index.js

var fs          = require('fs'),
    pathFn      = require('path'),
    ejs         = require('ejs'),
    requestCard = require('mtg-card-sync');

var cardTmplThemeSrc = pathFn.join(hexo.theme_dir, 'plugins/mtg-card-jp/card.ejs');
var cardTmplOriginalSrc = pathFn.join(__dirname, './card.ejs');
var cardTmplSrc = (fs.existsSync(cardTmplThemeSrc)? cardTmplThemeSrc: cardTmplOriginalSrc);

var cardTmpl = ejs.compile(
  fs.readFileSync(cardTmplSrc, 'utf8'),
  {});

var cardNameRegex = /《([^/(》]*)(\/[^(》]*)?(?:\(([^)]+)\))?》/g

hexo.extend.filter.register('before_post_render', function(data) {
  data.content = data.content.replace(
    cardNameRegex,
    function(content, cardNameA, cardNameB, cardSet) {
      var enCardName = (cardNameB? cardNameB.substring(1): cardNameA);

      if (!enCardName) {
        return content;
      }

      var card = requestCard(enCardName, cardSet) || {};

      return cardTmpl({card: card, content: content}).replace(/(?:\r|\n)/g, '');
    });
});

hexo.extend.tag.register('mtg_card', function(args) {
  var source = args.join(' ');
  var enCardName, cardSet;
  var result;

  source.replace(cardNameRegex, function(content, cardNameA, cardNameB, cardSet) {
    var enCardName = (cardNameB? cardNameB.substring(1): cardNameA);

    if (!enCardName || !cardSet) {
      return '';
    }

    var card = requestCard(enCardName, cardSet);

    if (!card || !card.multiverseid) {
      return '';
    }

    var imageUrl = 'http://gatherer.wizards.com/Handlers/Image.ashx?multiverseid=' + card.multiverseid + '&type=card';

    result = '<img class="mtg_card" src="' + imageUrl + '"/>';

    return '';
  });

  return result;
})