/*
 * Copyright (C) 2010-2011 Dynare Team
 *
 * This file is part of Dynare.
 *
 * Dynare is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Dynare is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Dynare.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <cassert>
#include <algorithm>

#include "SteadyStateModel.hh"

SteadyStateModel::SteadyStateModel(SymbolTable &symbol_table_arg, NumericalConstants &num_constants, ExternalFunctionsTable &external_functions_table_arg, const StaticModel &static_model_arg) :
  DataTree(symbol_table_arg, num_constants, external_functions_table), static_model(static_model_arg)
{
}

void
SteadyStateModel::addDefinition(int symb_id, expr_t expr)
{
  AddVariable(symb_id); // Create the variable node to be used in write method

  assert(symbol_table.getType(symb_id) == eEndogenous
         || symbol_table.getType(symb_id) == eModFileLocalVariable
         || symbol_table.getType(symb_id) == eParameter);

  // Add the variable
  vector<int> v;
  v.push_back(symb_id);
  recursive_order.push_back(v);
  def_table[v] = expr;
}

void
SteadyStateModel::addMultipleDefinitions(const vector<int> &symb_ids, expr_t expr)
{
  for (size_t i = 0; i < symb_ids.size(); i++)
    {
      AddVariable(symb_ids[i]); // Create the variable nodes to be used in write method
      assert(symbol_table.getType(symb_ids[i]) == eEndogenous
             || symbol_table.getType(symb_ids[i]) == eModFileLocalVariable
             || symbol_table.getType(symb_ids[i]) == eParameter);
    }
  recursive_order.push_back(symb_ids);
  def_table[symb_ids] = expr;
}

void
SteadyStateModel::checkPass(bool ramsey_policy) const
{
  vector<int> so_far_defined;

  for (size_t i = 0; i < recursive_order.size(); i++)
    {
      const vector<int> &symb_ids = recursive_order[i];

      // Check that symbols are not already defined
      for (size_t j = 0; j < symb_ids.size(); j++)
        if (find(so_far_defined.begin(), so_far_defined.end(), symb_ids[j])
            != so_far_defined.end())
          {
            cerr << "ERROR: in the 'steady_state' block, variable '" << symbol_table.getName(symb_ids[j]) << "' is declared twice" << endl;
            exit(EXIT_FAILURE);
          }

      // Check that expression has no undefined symbol
      if (!ramsey_policy)
        {
          set<pair<int, int> > used_symbols;
          expr_t expr = def_table.find(symb_ids)->second;
          expr->collectVariables(eEndogenous, used_symbols);
          expr->collectVariables(eModFileLocalVariable, used_symbols);
          for (set<pair<int, int> >::const_iterator it = used_symbols.begin();
               it != used_symbols.end(); ++it)
            if (find(so_far_defined.begin(), so_far_defined.end(), it->first)
                == so_far_defined.end())
              {
                cerr << "ERROR: in the 'steady_state' block, variable '" << symbol_table.getName(it->first)
                     << "' is undefined in the declaration of variable '" << symbol_table.getName(symb_ids[0]) << "'" << endl;
                exit(EXIT_FAILURE);
              }
        }

      copy(symb_ids.begin(), symb_ids.end(), back_inserter(so_far_defined));
    }
}

void
SteadyStateModel::writeSteadyStateFile(const string &basename, bool ramsey_policy) const
{
  if (recursive_order.size() == 0)
    return;

  string filename = basename + "_steadystate2.m";

  ofstream output;
  output.open(filename.c_str(), ios::out | ios::binary);
  if (!output.is_open())
    {
      cerr << "ERROR: Can't open file " << filename << " for writing" << endl;
      exit(EXIT_FAILURE);
    }

  output << "function [ys_, params, info] = " << basename << "_steadystate2("
	 << "ys_, exo_, params)" << endl
         << "% Steady state generated by Dynare preprocessor" << endl
         << "    info = 0;" << endl;

  for (size_t i = 0; i < recursive_order.size(); i++)
    {
      const vector<int> &symb_ids = recursive_order[i];
      output << "    ";
      if (symb_ids.size() > 1)
        output << "[";
      for (size_t j = 0; j < symb_ids.size(); j++)
        {
          variable_node_map_t::const_iterator it = variable_node_map.find(make_pair(symb_ids[j], 0));
          assert(it != variable_node_map.end());
          dynamic_cast<ExprNode *>(it->second)->writeOutput(output, oSteadyStateFile);
          if (j < symb_ids.size()-1)
            output << ",";
        }
      if (symb_ids.size() > 1)
        output << "]";

      output << "=";
      def_table.find(symb_ids)->second->writeOutput(output, oSteadyStateFile);
      output << ";" << endl;
    }
  output << "    % Auxiliary equations" << endl;
  static_model.writeAuxVarInitval(output, oSteadyStateFile);
  output << "    check_=0;" << endl
         << "end" << endl;
}