parse.js

/*jslint indent: 2, maxlen: 80, continue: false, unparam: false */
/* -*- tab-width: 2 -*- */
/*global define: true, module: true, require: true */
((typeof define === 'function') && define.amd ? define : function (factory) {
  'use strict';
  var m = ((typeof module === 'object') && module), e = (m && m.exports);
  if (e) { m.exports = (factory(require, e, m) || m.exports); }
})(function (require) {
  'use strict';

  //function debugp() { return console.warn.apply(console, arguments); }
  var EX, trim, parseJson = require('json-parse-pmb'),
    startCmt = /^([\s,\[\{\}\]]*)\/(\*|\/)/, endBlkCmt = /\*\/([\s,\]\}]*)$/;


  EX = function parseCeson(data, opts) {
    return parseJson(EX.ceson2json(data), opts);
  };


  trim = (''.trim ? function (s) { return s.trim(); } : function (s) {
    return (s && s.replace(/^\s+/, '').replace(/\s+$/, ''));
  });


  function chopPrevChar(lines, chop) {
    var prevIdx = lines.length - 1, prevLn = lines[prevIdx];
    if (!prevLn) { return; }
    if (prevLn.slice(-1) === chop) { lines[prevIdx] = prevLn.slice(0, -1); }
  }


  function wrapperCodeCompatAtEndOfLine(tx) {
    return tx.replace(/[\);]+(\n\s*|)$/, '$1');
  }


  function extractLineText(ln, lnIdx) {
    if (lnIdx === 0) {
      // Only in first line of input: strip BOM
      if (ln.slice(0, 1) === '\uFEFF') { ln = ln.slice(1); }

      // Only in first line of input: strip leading wrapper code
      ln = trim(ln
        ).replace(/^\s*export\s+\w+\s+/, ''
        ).replace(/^[A-Za-z].*?[\(=]/, '');
    }
    ln = trim(ln);
    return ln;
  }


  function ceson2json(ceson) {
    if (!ceson) { return false; }
    if (typeof ceson !== 'string') { return false; }
    var json = [], inBlockComment = false, strConcat = false, afterCmt;

    function parseLine(ln, lnIdx) {
      ln = extractLineText(ln, lnIdx);

      //debugp(lnIdx + 1, { trimmed: ln });
      if (!ln) { return lnIdx; }
      if (inBlockComment) {
        afterCmt = endBlkCmt.exec(ln);
        //debugp('    ', { inBlkEnd: (afterCmt && afterCmt[0]) });
        if (!afterCmt) { return; }
        inBlockComment = false;
        ln = trim(afterCmt[1]);
      }
      inBlockComment = startCmt.exec(ln);
      //debugp('    ', { startCmt: (inBlockComment && inBlockComment[0]) });
      if (inBlockComment) {
        if (inBlockComment[2] === '/') {
          // line comment. there can't be anything after it.
          ln = inBlockComment[1];
          inBlockComment = false;
        } else {
          // block comment. does it end in the same line?
          afterCmt = endBlkCmt.exec(ln);
          ln = inBlockComment[1];
          //debugp('    ', { oneLnBlk: (afterCmt && afterCmt[1]) });
          inBlockComment = !afterCmt;
          if (afterCmt) { ln += afterCmt[1]; }
        }
        ln = trim(ln);
      }
      //debugp('    ', { SWITCHING: ln, concat: strConcat });
      switch (ln[0]) {
      case undefined:
        return;
      case '}':
      case ']':
        chopPrevChar(json, ',');
        break;
      case '+':
        chopPrevChar(json, '"');
        ln = json.pop() + ln.replace(/^\+\s*"/, '');
        break;
      case '"':
        if (strConcat) { ln = json.pop() + ln.slice(1); }
        break;
      }
      strConcat = (ln.slice(-1) === '+');
      if (strConcat) { ln = ln.replace(/"\s*\+$/, ''); }
      //debugp('    ', { ln: ln }, (strConcat ? '+CONCAT+' : '-'));
      json.push(ln);
    }
    ceson.split(/\n/).forEach(parseLine);
    json = json.join('\n');
    json = wrapperCodeCompatAtEndOfLine(json);
    return json;
  }


  EX.startCmt = startCmt;
  EX.endBlkCmt = endBlkCmt;
  EX.ceson2json = ceson2json;


  return EX;
});