toloframework/lib/boilerplate.js

Javascript/HTML/CSS compiler for Firefox OS or nodewebkit apps using modules in the nodejs style.

"use strict";

var ToloframeworkPermissiveJson = require("toloframework-permissive-json");
var Preprocessor = require("./boilerplate.preprocessor");
var Fatal = require("./fatal");


var codeGenerators = {
  View: require("./boilerplate.view"),
  Global: require("./boilerplate.global")
};


exports.registerCodeGenerator = function(name, generator) {
  codeGenerators[name] = generator;
};


exports.generateCodeFrom = function( src ) {
  var xjs = src.clone("xjs");
  if( false == xjs.exists() ) return src.read();

  debugger;
  try {
    var rawDef = parseXJS( xjs );
    var def = Preprocessor( rawDef );
    
    var boilerplate = codeGenerators[def[0]];
    if( !boilerplate ) {
      throw "Unknown code generator \"" + def[0] + "\"!\n"
        + "Registred generators are: " + Object.keys(codeGenerators).join(", ") + ".";
    }
    var output = boilerplate.generateCodeFrom( def, src.read(), src.name() );
    return output;
  }
  catch( ex ) {
    Fatal.fire(
      "Fatal error in " + xjs.getAbsoluteFilePath() + "!\n" + ex,
      src.name(),
      xjs.getAbsoluteFilePath());
  }
};


function parseXJS( xjs ) {
  var xjsFileContent = xjs.read();
  try {
    return ToloframeworkPermissiveJson.parse( xjsFileContent );
  }
  catch( ex ) {
    throw "Invalid permissive JSON syntax:\n" + ex.message + "\n\n"
      + getFewLinesOfCode( xjsFileContent, ex.index, 3 );
  }
}


function getFewLinesOfCode( code, issuePosition, linesToDisplay ) {
  if( typeof linesToDisplay === 'undefined' ) linesToDisplay = 3;
  var lineCount = 1;
  var currentIndex = 0;
  var previousIndex = 0;
  var lines = [];
  issuePosition = Math.min( issuePosition, code.length -1 );
  while( currentIndex < code.length ) {
    if( code.charAt( currentIndex ) === '\n' ) {
      lines.push({ line: lineCount, begin: previousIndex, end: currentIndex });
      if( lines.length > linesToDisplay )
        lines.shift();
      previousIndex = currentIndex + 1;
      lineCount++;
      if( currentIndex >= issuePosition ) break;
    }
    currentIndex++;
  }

  debugger;
  var columnsSeparator = ": ";
  var lineNumbersLengths = lines.map(x => ("" + x.line).length);
  var spaceForLineNumbers = lineNumbersLengths.reduce((a,v) => Math.max(a, v), 0);
  var output = lines.map(
    x => padStart(x.line, spaceForLineNumbers)
      + columnsSeparator + code.substring(x.begin, x.end) ).join("\n");
  var lastLineBegin = lines.pop().begin;
  output += "\n" + padStart("^",
    spaceForLineNumbers + columnsSeparator.length + issuePosition - lastLineBegin - 1);
  return output;
}

function padStart( text, targetLength, padString ) {
  if( typeof padString === 'undefined' ) padString = ' ';
  text = "" + text;
  while( text.length < targetLength )
    text = padString + text;
  return text;
}