SOURCE CODE: Uize.Parse.Code.StringLiteral

/*______________
|       ______  |   U I Z E    J A V A S C R I P T    F R A M E W O R K
|     /      /  |   ---------------------------------------------------
|    /    O /   |    MODULE : Uize.Parse.Code.StringLiteral Object
|   /    / /    |
|  /    / /  /| |    ONLINE : http://uize.com
| /____/ /__/_| | COPYRIGHT : (c)2014 UIZE
|          /___ |   LICENSE : Available under MIT License or GNU General Public License
|_______________|             http://uize.com/license.html
*/

/* Module Meta Data
  type: Object
  importance: 1
  codeCompleteness: 100
  docCompleteness: 5
*/

/*?
  Introduction
    The =Uize.Parse.Code.StringLiteral= module defines a parser object for string literals.

    *DEVELOPERS:* `Chris van Rensburg`
*/

Uize.module ({
  name:'Uize.Parse.Code.StringLiteral',
  required:'Uize.Str.Replace',
  builder:function () {
    'use strict';

    var
      /*** General Variables ***/
        _escapedCharsLookup = {
          '\\':'\\\\',
          '\n':'\\n',
          '\r':'\\r',
          '"':'\\"',
          '\'':'\\\''
        },
        _escapeReplacer = Uize.Str.Replace.replacerByLookup (_escapedCharsLookup),
        _unescapeReplacer = Uize.Str.Replace.replacerByLookup (Uize.reverseLookup (_escapedCharsLookup))
    ;

    return Uize.mergeInto (
      function (_source,_index) {
        this.parse (_source,_index);
      },

      {
        prototype:{
          source:'',
          index:0,
          length:0,
          isValid:false,
          value:'',

          parse:function (_source,_index) {
            var
              m = this,
              _sourceLength = (m.source = _source = _source || '').length
            ;
            m.index = _index || (_index = 0);
            var _currentChar = _source.charAt (_index);
            if (m.isValid = _currentChar == '"' || _currentChar == '\'') {
              _index++;
              var _inEscape = false;
              while (_index < _sourceLength) {
                var _char = _source.charAt (_index);
                if (_char == '"' && !_inEscape) {
                  m.isValid = true;
                  m.value = _unescapeReplacer (_source.slice (m.index + 1,_index));
                  m.length = ++_index - m.index;
                  break;
                } else {
                  _inEscape = _inEscape ? false : _char == '\\';
                  _index++;
                }
              }
            } else {
              m.value = '';
              m.length = 0;
            }
          },

          serialize:function () {return this.isValid ? '"' + _escapeReplacer (this.value) + '"' : ''}
        }
      }
    );
  }
});