CompositeAssignmentNode.cpp

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/* -*- C++ -*- */

#ifndef _ASSIGNMENT_NODE_CPP_
#define _ASSIGNMENT_NODE_CPP_

#ifndef _MADARA_NO_KARL_

#include <iostream>

#include "madara/expression/ComponentNode.h"
#include "madara/expression/Visitor.h"
#include "madara/expression/CompositeAssignmentNode.h"
#include "madara/expression/LeafNode.h"


// Ctor

madara::expression::CompositeAssignmentNode::CompositeAssignmentNode (
  logger::Logger & logger,
  ComponentNode *left, ComponentNode *right)
: CompositeUnaryNode (logger, right)
{
  var_ = dynamic_cast <VariableNode *> (left);

  if (!var_)
    array_ = dynamic_cast <CompositeArrayReference *> (left);
}

madara::knowledge::KnowledgeRecord
madara::expression::CompositeAssignmentNode::item (void) const
{
  return knowledge::KnowledgeRecord ("=");
}


madara::knowledge::KnowledgeRecord
madara::expression::CompositeAssignmentNode::prune (bool & can_change)
{
  bool left_child_can_change = false;
  bool right_child_can_change = false;
  madara::knowledge::KnowledgeRecord right_value;

  if (this->var_ != 0 || this->array_ != 0)
    left_child_can_change = true;
  else
  {
    madara_logger_ptr_log (logger_, logger::LOG_ERROR,
      "CompositeAssignmentNode: "
      "KARL COMPILE ERROR (=): "
      "Assignments must have a variable left hand side.\n");

    throw KarlException ("CompositeAssignmentNode: "
      "KARL COMPILE ERROR (=): "
      "Assignments must have a variable left hand side");
  }

  if (this->right_)
  {
    right_value = this->right_->prune (right_child_can_change);
    if (!right_child_can_change && dynamic_cast <LeafNode *> (right_) == 0)
    {
      delete this->right_;
      this->right_ = new LeafNode (*(this->logger_), right_value);
    }
  }
  else
  {
    // we should never be able to get here but whatever
    madara_logger_ptr_log (logger_, logger::LOG_ERROR,
      "CompositeAssignmentNode: KARL COMPILE ERROR: "
      "Assignment has no right expression\n");

    throw KarlException (
      "CompositeAssignmentNode: KARL COMPILE ERROR: "
      "Assignment has no right expression\n"); 
  }

  can_change = left_child_can_change || right_child_can_change;

  return right_value;
}

madara::knowledge::KnowledgeRecord 
madara::expression::CompositeAssignmentNode::evaluate (
  const madara::knowledge::KnowledgeUpdateSettings & settings)
{
  madara::knowledge::KnowledgeRecord rhs = right_->evaluate (settings);

  // get the value from the right side and set the variable's value with it
  //madara::knowledge::KnowledgeRecord value = right_->evaluate ();
  if (var_)
  {
    madara_logger_ptr_log (logger_, logger::LOG_MINOR,
      "CompositeAssignmentNode::evaluate: "
      "Attempting to set variable %s to %s.\n",
      var_->expand_key ().c_str (),
      rhs.to_string ().c_str ());

    var_->set (rhs, settings);
  }
  else if (array_)
  {
    madara_logger_ptr_log (logger_, logger::LOG_MINOR,
      "CompositeAssignmentNode::evaluate: "
      "Attempting to set index of var %s to %s.\n",
      array_->expand_key ().c_str (),
      rhs.to_string ().c_str ());

    array_->set (rhs, settings);
  }
  else
  {
    madara_logger_ptr_log (logger_, logger::LOG_MINOR,
      "left hand side was neither a variable nor an array reference. "
      "Check your expression for errors.\n");
  }

  // return the value
  return rhs;
}


// accept a visitor
void 
madara::expression::CompositeAssignmentNode::accept (Visitor &visitor) const
{
  visitor.visit (*this);
}

#endif // _MADARA_NO_KARL_

#endif /* _ASSIGNMENT_NODE_CPP_ */