import pos from 'pos';
import _ from 'underscore';

export function getPartsOfSpeech (input) {
  try {
    const words = new pos.Lexer().lex(input);
    const tagger = new pos.Tagger();
    return tagger.tag(words);
  }
  catch (e) {
    return undefined;
  }
}

export function getPartsOfSpeechTags(input){
  const wordsTags = getPartsOfSpeech(input);
  if (wordsTags) {
    return wordsTags.map((b) => {
      return b[1]
    })
  }

}

export function getPartsOfSpeechWords(input){
  const wordsTags = getPartsOfSpeech(input);
  if (wordsTags) {
    return wordsTags.map((b) => {
      return b[0];
    })
  }
}

export function getPartsOfSpeechWordsWithTags(input){
  const wordsTags = getPartsOfSpeech(input);
  if (wordsTags) {
    return wordsTags.map((b) => {
      return [b[0], b[1]];
    })
  }
}

export function checkPOSEquivalancy (input, target) {
  const inputTags = getPartsOfSpeechTags(input);
  const targetTags = getPartsOfSpeechTags(target);
  return _.isEqual(inputTags,targetTags);
}

export function getPOSTagPairs (input, target) {
  const inputTags = getPartsOfSpeechTags(input);
  const targetTags = getPartsOfSpeechTags(target);
  return _.zip(inputTags, targetTags);
}

export function getPOSTransformations(input, target) {
  const arraytagger = getPOSTagPairs(input, target);
  const arrayDifference = arraytagger.filter((b) => {
    return b[0] !== b[1];
  });
  return arrayDifference.map((b) => {
    return b[0] + '|' + b[1];
  });
}