@elderjs/shortcodes/lib/parser.js

An Shortcode parser with support of arguments, key-value attributes, nesting, and async.

/*
 * META Platform library
 * Shortcode parser
 *
 * @author META Platform <www.meta-platform.com>
 * @license See LICENSE file distributed with this source code
 */

var Tokenizer = require("./tokenizer.js");

/**
 * Parser constructor
 */
var ShortcodeParser = function (opts) {
  if (!opts) opts = {};

  this.shortcodes = {};

  this.options = {
    openPattern: opts.openPattern || "\\[",
    closePattern: opts.closePattern || "\\]",
  };
};

/**
 * Add shortcode
 *
 * @param string shortcode
 * @param function handler
 */
ShortcodeParser.prototype.add = function (shortcode, handler) {
  this.shortcodes[shortcode] = handler;
};

/**
 * Parse string and process shortcodes
 *
 * @param string input
 */
ShortcodeParser.prototype.parse = async function (input) {
  var self = this;

  var tokenizer = Tokenizer(input);

  await tokenizer.tokenize(ShortcodeParser.parsers.tagOpen, this);

  return tokenizer.getOutput();
};

/**
 * Tokenizers
 */
ShortcodeParser.parsers = {};

ShortcodeParser.parsers.error = function (t, ctx) {
  if (ctx && ctx.name) {
    if (ctx.name) t.toBuffer(this.options.openPattern.replace(/\\/g, "") + "!" + ctx.name);

    if (ctx.errorUnclosed) t.toBuffer("!" + this.options.closePattern.replace(/\\/g, "") + ctx.content);
    else if (ctx.content !== "")
      t.toBuffer(
        "!" +
          this.options.closePattern.replace(/\\/g, "") +
          ctx.content +
          this.options.openPattern.replace(/\\/g, "") +
          "/!" +
          ctx.name +
          "!" +
          this.options.closePattern.replace(/\\/g, "")
      );
    else t.toBuffer("!/" + this.options.closePattern.replace(/\\/g, ""));
  } else {
    t.toBuffer(this.options.openPattern.replace(/\\/g, "") + "^!" + this.options.closePattern.replace(/\\/g, ""));
  }

  t.closeContext();

  if (ctx.parentParser) {
    return ctx.parentParser;
  } else if (ctx.restoreOnError) {
    t.flushBuffer();
    return ShortcodeParser.parsers.tagOpen;
  } else {
    t.flushBuffer();
    t.flushRest();
  }

  return false;
};

ShortcodeParser.parsers.tagOpen = function (t) {
  if (!t.match(this.options.openPattern + "(?!\\/)", true)) {
    t.flushBuffer();
    t.flushRest();
    return false;
  }

  t.flushBuffer();

  t.openContext({
    name: null,
    args: {},
    content: "",
  });

  return ShortcodeParser.parsers.tagName;
};

ShortcodeParser.parsers.tagName = function (t, ctx) {
  if (!t.match("[a-zA-Z0-9\\-_]+", false, true)) return ShortcodeParser.parsers.error;

  //ctx.name = t.clearBuffer().toLowerCase();
  ctx.name = t.clearBuffer();

  return ShortcodeParser.parsers.tagBody;
};

ShortcodeParser.parsers.tagBody = function (t, ctx) {
  t.clearBuffer();

  if (t.isEnd()) return ShortcodeParser.parsers.error;

  //Attributes?
  if (t.match(".*?(?=(\\/)?" + this.options.closePattern + "|$)", false, false, false)) {
    t.skip(1);
    t.clearBuffer();
    return ShortcodeParser.parsers.params;

    //Self closing?
  } else if (t.match("^\\/" + this.options.closePattern, true)) {
    return ShortcodeParser.parsers.process;

    //Pair closing
  } else if (t.match("^" + this.options.closePattern, true)) {
    return ShortcodeParser.parsers.content;
  }

  return ShortcodeParser.parsers.error;
};

ShortcodeParser.parsers.params = function (t, ctx) {
  var addParam = function () {
    if (t.getBuffer().trim() !== "") {
      if (ctx.argKey) {
        ctx.args[ctx.argKey] = t.clearBuffer() || undefined;
      } else {
        const v = t.clearBuffer();
        ctx.args[v] = v;
      }
    }
    // if (t.getBuffer().trim() !== "") {
    //   if (!ctx.argKey && !Array.isArray(ctx.args) && Object.keys(ctx.args).length === 0) {
    //     ctx.args = [];
    //   }
    //   if (ctx.argKey) {
    //     const v = {};
    //     v[ctx.argKey] = t.clearBuffer();
    //     ctx.args.push(v);
    //   } else {
    //     ctx.args.push(t.clearBuffer());
    //   }
    // } else {
    //   if (ctx.argKey) ctx.args[ctx.argKey] = t.clearBuffer();
    // }

    delete ctx.argKey;
  };

  if (
    !t.match("^\\/" + this.options.closePattern, false, false, false) &&
    !t.match("^" + this.options.closePattern, false, false, false) &&
    !t.isEnd()
  ) {
    //Escape
    if (t.match("^\\\\")) {
      t.next(true, true);

      //Quotes?
    } else if (t.match("^(\"|'|&quot;)", false, true)) {
      ctx.quoteType = t.clearBuffer();

      return ShortcodeParser.parsers.quote;

      //Space?
    } else if (t.match("^ ")) {
      addParam();

      //key?
    } else if (t.match("^=")) {
      if (ctx.argKey) t.toBuffer("=");
      else ctx.argKey = t.clearBuffer();
    } else {
      t.next(true, true);
    }

    return ShortcodeParser.parsers.params;
  }

  addParam();

  return ShortcodeParser.parsers.tagBody;
};

ShortcodeParser.parsers.quote = function (t, ctx) {
  while (!t.match("^" + ctx.quoteType) && !t.isEnd()) {
    t.match("^\\\\");
    t.next(true, true);
  }

  delete ctx.quoteType;

  return ShortcodeParser.parsers.params;
};

ShortcodeParser.parsers.content = function (t, ctx) {
  //Subtag?
  if (t.match(this.options.openPattern, true)) {
    //Close
    if (t.match("^\\/", false, false, false)) {
      if (t.match("^\\/" + ctx.name + this.options.closePattern, true)) {
        ctx.content += t.getBuffer();
        t.skip(-this.options.closePattern.replace(/\\/g, "").length);

        return ShortcodeParser.parsers.close;
      } else {
        t.skip(-this.options.openPattern.replace(/\\/g, "").length);
        t.eat(this.options.openPattern.replace(/\\/g, "").length + 1);

        return ShortcodeParser.parsers.content;
      }

      //Open
    } else {
      ctx.content += t.clearBuffer();

      t.openContext({
        name: null,
        args: {},
        content: "",
        parentParser: ShortcodeParser.parsers.content,
      });

      return ShortcodeParser.parsers.tagName;
    }

    return ShortcodeParser.parsers.content;
  }

  ctx.content += t.clearBuffer();
  ctx.errorUnclosed = true;

  return ShortcodeParser.parsers.error;
};

ShortcodeParser.parsers.close = function (t, ctx) {
  t.clearBuffer();

  if (!t.match(this.options.closePattern, true)) {
    return ShortcodeParser.parsers.error;
  }

  //if(t.getBuffer() != ctx.name)
  //	return ShortcodeParser.parsers.error;

  return ShortcodeParser.parsers.process;
};

ShortcodeParser.parsers.process = async function (t, ctx) {
  //if not shortchode
  if (!ctx || !ctx.name || ctx.name === "") return false;

  t.clearBuffer();

  //if shortcode not registered
  if (!this.shortcodes[ctx.name]) {
    ctx.restoreOnError = true;
    return ShortcodeParser.parsers.error;
  }

  const shortcodeOutput = await this.shortcodes[ctx.name].call(ctx, ctx.args, ctx.content);
  t.toBuffer(shortcodeOutput);

  t.closeContext();

  if (ctx.parentParser) {
    return ctx.parentParser;
  } else {
    t.flushBuffer();
    return ShortcodeParser.parsers.tagOpen;
  }
};

//Export
module.exports = function (opts) {
  return new ShortcodeParser(opts);
};