sclass RuleEngine1 {

  int minScore = 50; // minimal percentage score for rule matching

  LPair<S> rules;

  bool printMappings, printGroupedData, printRejectedVars;

  Map<PairS, Set<S>> ruleVariables = new Map;

  O preprocess = f id; // f ai_groupSimplestNounPhrases

  *() {}

  *(S _rules) { addRules(_rules); }

  void addRules(S _rules) {

    _rules = mapEachLine(preprocess, _rules);

    if (printGroupedData) print(_rules);

    rules = ai_findDoubleArrowRulesAsPairs(_rules);

    for (PairS rule : rules)

      ruleVariables.put(rule, ai_wordsInBothSidesOfPair_uncurly(rule));

  }

  void processInput(S input) {

    print("\nInput: " + tok_dropCurlyBrackets(input));

    temp tempIndent();

    for (S in : interpretations(input)) {

      print("\nInterpretation: " + formatForUser(in));

      Set<S> out = litciset();

      interpretRecursively(in, 5, out);

    }

  }

  void interpretRecursively(S input, int level, Set<S> out) {

    if (level <= 0) ret;

    LS interpretations = interpretations((S) callF(preprocess, input));

    temp tempIndent();

    for (S in : addAllAndReturnNew(out, interpretations)) {

      print(" => " + formatForUser(in));

      for (S s : lithashset(in, ai_superSimpleVerbCorrector(in)))

        interpretRecursively(s, level-1, out);

    }

  }

  LS defaultParse(S s) {

    ret codeTokens_lazy_uncurly(javaTokNPunctuationWithBrackets_cached(s));

  }

  LS interpretations(S input) {

    LS tokI = defaultParse(input);

    //print("Raw parse: " + tokI);

    new LS interpretations;

    for (PairS rule : rules) {

      LS tokR = defaultParse(rule.a);

      final SS map = zipTwoListsToCIMap_strict_withoutEquals(tokR, tokI);

      if (map == null) continue;

      // Found matching rule

      int score = l(tokR)-l(map);

      L<S> nonVars = withoutDollarVars(listMinusSet(keys(map), ruleVariables.get(rule)));

      if (printRejectedVars && nempty(nonVars)) print("Rejected vars: " + nonVars);

      if (nempty(nonVars)) score = 0;

      int percentScore = ratioToIntPercent(score, l(tokR));

      if (printMappings) print("  " + percentScore + "% " + reverseMapCI_joinDuplicatesWithPlus(map) + " | " + rule.a);

      if (percentScore < minScore) continue;

      // Make consequence

      S c = rule.b;

      c = join(mapCodeTokens(javaTok(c), func(S s) -> S { getOrKeep_tryUncurlied(map, s) }));

      c = join(mapCodeTokens(javaTokWithBrackets(c), func(S s) -> S { getOrKeep_tryUncurlied(map, s) }));

      //c = javaTokWithBrackets_recursiveTransform(func(S s) -> S { getOrKeep(map, s) }, c);

      interpretations.add(c);

    }

    ret interpretations;

  }

  S formatForUser(S s) {

    ret ai_superSimpleVerbCorrector(tok_dropCurlyBrackets(s));

  }

}