/**
 * Config section
 * Define the math symbols list below
 */

var characters = ['+', '-', '±', '=', '≠', '≈', '≅', '≡', '*', '×', '÷', '/', '<', '>', '≤', '≥', '∑', '∏', '∫', '∩', '∀', '∃', '∅', '∂', '∇', '⊂', '⊃', '∪', '∈', '∉', '∋', '∠', '∴', '⊕', '⊗', '⊥', '√', '∝', '∞'];

/**
 * Code section
 */

var result = {
  success: false
};

if (crowdin.contentType === 'application/vnd.crowdin.text+plural') {
  var obj = JSON.parse(crowdin.source);

  if (obj[crowdin.context.pluralForm] != null) {
    source = obj[crowdin.context.pluralForm]
  } else {
    source = obj.other
  }
} else {
  source = crowdin.source
}

var translation = crowdin.translation;
characters.indexOf('-') !== -1 ? characters[characters.indexOf('-')] = '\\-' : null;
regex = new RegExp('[' + characters.join('') + ']', 'g');

sourceMatch = source.match(regex);
translationMatch = translation.match(regex);

function UnionArrays (firstArray, secondArray) {
  var outputArray = [];

  if (firstArray.length && secondArray.length) {
    var tempArray = firstArray.concat(secondArray);

    tempArray.sort();
    outputArray = [tempArray[0]];

    for (var i = 1; i < tempArray.length; i++) {
      if (tempArray[i] !== tempArray[i - 1]) {
        outputArray.push(tempArray[i])
      }
    }

    return outputArray
  } else if (!firstArray.length) {
    secondArray.length ? outputArray = secondArray : null
  } else if (!secondArray.length) {
    firstArray.length ? outputArray = firstArray : null
  }

  return outputArray
}

/**
 * @return {string}
 */
function JoinWithQuotes (array, slice) {
  return slice ? array.slice(0, 5).join('", "') + '" and others.' : '"' + array.join('", "') + '".'
}

var sourceResult = {};
var translationResult = {};
var sourceProps = [];
var translationProps = [];
var mergedProps = [];
var solution = [];

if (sourceMatch != null) {
  for (var i = 0; i < sourceMatch.length; ++i) {
    var currentCharacter = sourceMatch[i];

    sourceResult[currentCharacter] !== undefined ? ++sourceResult[currentCharacter] : sourceResult[currentCharacter] = 1
  }

  sourceProps = Object.getOwnPropertyNames(sourceResult)
}

if (translationMatch != null) {
  for (var j = 0; j < translationMatch.length; ++j) {
    currentCharacter = translationMatch[j];

    translationResult[currentCharacter] !== undefined ? ++translationResult[currentCharacter] : translationResult[currentCharacter] = 1
  }

  translationProps = Object.getOwnPropertyNames(translationResult)
}

mergedProps = UnionArrays(sourceProps, translationProps);

if (mergedProps.length) {
  var replacementArray = [];
  var missingArray = [];
  var extraArray = [];

  for (var u = 0; u < mergedProps.length; u++) { // Sort extra/missing and add to array
    if (sourceProps.indexOf(mergedProps[u]) !== -1 && translationProps.indexOf(mergedProps[u]) !== -1) {
      if (sourceResult[mergedProps[u]] === translationResult[mergedProps[u]]) {
      } else {
        if (sourceResult[mergedProps[u]] >= translationResult[mergedProps[u]]) {
          missingArray.push(mergedProps[u])
        } else if (sourceResult[mergedProps[u]] <= translationResult[mergedProps[u]]) {
          extraArray.push(mergedProps[u])
        }
      }
    } else if (sourceProps.indexOf(mergedProps[u]) !== -1 && translationProps.indexOf(mergedProps[u]) === -1) {
      missingArray.push(mergedProps[u])
    } else if ((sourceProps.indexOf(mergedProps[u]) === -1 && translationProps.indexOf(mergedProps[u]) !== -1)) {
      extraArray.push(mergedProps[u]);
      replacementArray.push(mergedProps[u])
    }
  }

  if (replacementArray != null) { // Add fixes for extra symbols
    var tempIndex;
    var repRegex = new RegExp('[' + replacementArray.join('') + ']', 'g');

    for (i = 0; i < replacementArray.length; i++) {
      for (j = 0; j < translationResult[replacementArray[i]]; j++) {
        tempIndex = repRegex.exec(translation).index;
        solution.push({
          from_pos: tempIndex,
          to_pos: tempIndex + 1,
          replacement: ''
        })
      }
    }
  }

  if (!extraArray.length && !missingArray.length) {
    result.success = true
  } else {
    result.fixes = solution;
    result.message = 'Math symbols.';

    if (missingArray.length) {
      result.message += ' Missing in translation: ';
      missingArray.length < 6 ? result.message += JoinWithQuotes(missingArray, false) : result.message += JoinWithQuotes(missingArray, true)
    }

    if (extraArray.length) {
      result.message += ' Extra in translation: ';
      extraArray.length < 6 ? result.message += JoinWithQuotes(extraArray, false) : result.message += JoinWithQuotes(extraArray, true)
    }
  }
} else {
  result.success = true
}

return result;