!include once #1027630 // Msg

static transformable record LogicRule(lhs, rhs) {}

cmodule NewEngineSpike > DynPrintLog {
  L<Msg> msgs;
  bool verbose = true, printNonMatches = true;
  
  start-thread {
    if (empty(msgs))
      setField(msgs := mainCruddieLog());
    print("Have " + nMessages(msgs));
    pnlStruct(takeFirst(2, msgs));
    L<Msg> msgs2 = whereFieldIsTrue fromUser(msgs);
    new L props;
    for (Msg msg : takeFirst(5, msgs2))
      print(addAndReturn(props, ll(msg, "was understood correctly")));
    props.add(print(ll(get(msgs2, 5), "is a wrong recognition")));

    LogicRule rule = new(
      ll("$x", "is a wrong recognition"),
      ll("$x", "should be corrected"));

    for (O prop : props)
      applyLogicRuleToFact(rule, prop);
  }

  // use standard deep-zip & replace utils
  Map deepZip(O a, O b) { ret newGazelle_deepZip1(a, b); }
  O replaceVars(O o, Map map) { ret replaceVars_understandsTransformableAndList(o, map); }

  // define what a variable is
  bool isVar(O o) { ret o instanceof S && isDollarVar(o/S); }

  void applyLogicRuleToFact(LogicRule rule, O fact) {
    O cond = rule.lhs, rhs = rule.rhs;
    
    // now we match the fact to our condition
    Map map = deepZip(cond, fact);

    // Discard unless all keys are variables
    if (map != null && !all(keys(map), s -> isVar(s))) map = null;
    
    if (map == null)
      ret with if (printNonMatches) print("Non-match: " + quote(cond) + " / " + quote(fact));

    // Now we have a proper mapping with the keys being variables!
    if (verbose) print("Match: " + quote(cond) + " / " + quote(fact));

    // Apply mapping to right hand side
    O rhs_replaced = replaceVars(rhs, map);
    if (verbose) print(+rhs_replaced);
    
    Map trail = litorderedmap(op := "applyLogicRuleToFact",
      +rule, +fact, +rhs_replaced);

    addRewrittenRHS(rhs_replaced, trail);
  }

  void addRewrittenRHS(O rhs, O trail) {
    print("Derived: " + rhs);
  }
}