pbxproj/lib/stage.js

parse & stringify xcode pbxproj format

'use strict';

/*
 * Module dependencies
 */

var _ = require('lodash');
var util = require('util');


/*
 * Stage of parsing process (parent constructor)
 */

var ParserStage = module.exports = function (ctx, data, cursor, line, back) {
  this.data = data;
  this.cursor = cursor || 0;
  this.expected = [];
  this.back = back || _.noop;
  this.ctx = ctx;
  this.line = line || 0;
};

/*
 * Error formater
 */

ParserStage.prototype.error = function () {
  throw new Error(
    [util.format('[%d:%d]', this.line, this.cursor), ':']
      .concat(_.toArray(arguments))
      .join(' ')
  );
};

/*
 * ExpectedError formater
 */

ParserStage.prototype.expectedError = function (found) {
  this.error('Expected :', this.expected.map(function(expect) {
    return '\'' + expect.pattern + '\'';
  }).join(' or '), 'found :', found);
};

/*
 * Register a new expect rule : pattern + cycle callback
 */

ParserStage.prototype.expect = function (pattern, cycle) {
  this.expected.push({pattern: pattern, cycle: cycle});
};

/*
 * Check if next caracter match any expect rule
 */

ParserStage.prototype.matchNext = function () {
  var stage = this;

  if (this.cursor >= this.data.length) return;  

  return _.find(this.expected, function (expect) {
    return stage.data[stage.cursor].match(expect.pattern);
  });
};

/*
 * Run one parsing cycle
 */

ParserStage.prototype.run = function () {
  var car;
  var nextStage;
  var match = this.matchNext();
  var cycle = !!match ? match.cycle : null;

  if (this.cursor >= this.data.length && this.expected.length) {
    this.expectedError('END');
  } else if (this.cursor < this.data.length && !!match) {
    car = this.data[this.cursor];
    this.cursor++;
    this.expected = [];
    cycle(car);
  } else if (this.data[this.cursor].match(/\s/)) {
    this.cursor++;
    this.run();
  } else if (this.cursor < this.data.length && !match) {
    this.expectedError(this.data[this.cursor]);
  }

  if (this.cursor < this.data.length && this.data[this.cursor] === '\n') this.line++;
};