SOURCE CODE: Uize.Loc.Util.LocModuleCompiler (view docs)

/*______________
|       ______  |   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.Loc.Util.LocModuleCompiler Package
|   /    / /    |
|  /    / /  /| |    ONLINE : http://uize.com
| /____/ /__/_| | COPYRIGHT : (c)2014-2016 UIZE
|          /___ |   LICENSE : Available under MIT License or GNU General Public License
|_______________|             http://uize.com/license.html
*/

/* Module Meta Data
  type: Package
  importance: 3
  codeCompleteness: 100
  docCompleteness: 100
*/

/*?
  Introduction
    The =Uize.Loc.Util.LocModuleCompiler= module provides a method for compiling UIZE loc modules (=.loc= files) to JavaScript modules.

    *DEVELOPERS:* `Chris van Rensburg`
*/

Uize.module ({
  name:'Uize.Loc.Util.LocModuleCompiler',
  required:[
    'Uize.Build.Util',
    'Uize.Json',
    'Uize.Str.Split'
  ],
  builder:function () {
    'use strict';

    var
      /*** Variables for Performance Optimization ***/
        _split = Uize.Str.Split.split,

      /*** General Variables ***/
        _tokenRegExp = /\[\[([^\[\]]+)\]\]/
    ;

    return Uize.package ({
      compile:function (_moduleName,_source,_locale) {
        function _compileTokenizedStringExpression (_string) {
          var _expressionParts = [];
          Uize.forEach (
            _split (_string,_tokenRegExp),
            function (_segment,_segmentNo) {
              var _segmentIsToken = _segmentNo % 2;
              if (_segmentIsToken || _segment)
                _expressionParts.push (
                  (_segmentIsToken ? 'i [' : '') +
                  Uize.Json.to (_segment) +
                  (_segmentIsToken ? ']' : '')
                )
              ;
            }
          );
          return _expressionParts.join (' + ');
        }
        var
          _strings = Uize.Build.Util.readSimpleDataFile (_source),
          _required = [],
          _pluralsModuleRequired,
          _pluralsModuleName = 'Uize.Loc.Plurals.Langs.' + Uize.capFirstChar (_locale.replace (/[\-_].+$/,'')),
          _builder = [
            'function () {',
            '  return {',
              Uize.map (
                Uize.keys (_strings),
                function (_key) {
                  var _stringValue = _strings [_key];
                  if (Uize.isPlainObject (_stringValue)) {
                    var
                      _pluralCategories = Uize.keys (_stringValue),
                      _specialCasesLookup = {}
                    ;
                    Uize.forEach (
                      _pluralCategories,
                      function (_pluralCategory) {
                        if (Uize.isNumber (+_pluralCategory))
                          _specialCasesLookup [_pluralCategory] = 1
                        ;
                      }
                    );
                    _stringValue = [].concat (
                      'function (i) {',
                      '      var n = Uize.Loc.Plurals.Util.resolveValue (i);',
                      '      switch (' + Uize.Json.to (_specialCasesLookup,'mini') + '.hasOwnProperty (n) ? n + \'\' : ' + _pluralsModuleName + '.getPluralCategory (n)) {',
                      Uize.map (
                        _pluralCategories,
                        function (_pluralCategory) {
                          return (
                            '        ' +
                            '\'' + _pluralCategory + '\': return ' +
                            _compileTokenizedStringExpression (_stringValue [_pluralCategory]) + ';'
                          );
                        }
                      ),
                      '      }',
                      '    }'
                    ).join ('\n');
                    if (!_pluralsModuleRequired) {
                      _required.push ('Uize.Loc.Plurals.Util',_pluralsModuleName);
                      _pluralsModuleRequired = true;
                    }
                  } else if (_tokenRegExp.test (_stringValue)) {
                    _stringValue =
                      'function (i) {return ' + _compileTokenizedStringExpression (_stringValue) + '}'
                    ;
                  } else {
                    _stringValue = Uize.Json.to (_stringValue);
                  }
                  return '    ' + Uize.Json.to ('loc_' + _key) + ':' + _stringValue;
                }
              ).join (',\n'),
            '  };',
            '}'
          ].join ('\n')
        ;

        return Uize.Build.Util.moduleAsText ({
          name:_moduleName,
          required:_required,
          builder:_builder
        });
      }
    });
  }
});