/*
 * Project: MoleCuilder
 * Description: creates and alters molecular systems
 * Copyright (C)  2013 Frederik Heber. All rights reserved.
 * 
 *
 *   This file is part of MoleCuilder.
 *
 *    MoleCuilder 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 2 of the License, or
 *    (at your option) any later version.
 *
 *    MoleCuilder 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 MoleCuilder.  If not, see <http://www.gnu.org/licenses/>.
 */

/*
 * PythonScripting.cpp
 *
 *  Created on: Aug 26, 2013
 *      Author: heber
 */

// include config.h
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

// boost::python uses placement new which is incompatible with MemDebug.
#include "PythonScripting_impl.hpp"
#include "PythonScripting.hpp"

#include <string>

//#include "CodePatterns/MemDebug.hpp"

bool executePythonScriptFile(const boost::filesystem::path &pythonfilename)
{
  if (exists(pythonfilename)) {
    // parse file into a string
    std::ifstream pythonfile(pythonfilename.string().c_str());
    std::string pythonscript( std::istreambuf_iterator<char>(pythonfile),
        (std::istreambuf_iterator<char>()) );
    return executePythonScript(pythonscript, pythonfilename.string());
  }
  return false;
}

bool executePythonScript(const std::string &python_string, const std::string &python_scripttitle)
{
  std::stringstream input(python_string);
  std::stringstream buffer_import;
  std::stringstream buffer_else;
  // move all lines with "import" to the beginning
  std::string current_line;
  std::string moduleName;
  while(std::getline(input,current_line,'\n')){
    if (current_line.find("import ") != std::string::npos) {
      if (current_line.find(PYMOLECUILDER_MODULE_NAME) != std::string::npos) {
    	  // ignore a PyMoleCuilder import, use the AS however.
    	  const size_t lowerCaseAsPos = current_line.find("as");
    	  const size_t upperCaseAsPos = current_line.find("AS");
    	  size_t moduleNameStart = std::string::npos;
				if (lowerCaseAsPos != std::string::npos)
					moduleNameStart = lowerCaseAsPos+2+1;
				if (upperCaseAsPos != std::string::npos)
					moduleNameStart = upperCaseAsPos+2+1;
				if (moduleNameStart != std::string::npos) {
					const size_t moduleNameEnd = current_line.find(" ", moduleNameStart);
					moduleName = current_line.substr(
        	  moduleNameStart,
						moduleNameEnd == std::string::npos ? moduleNameEnd : moduleNameEnd  - moduleNameStart
					);
	      	ELOG(2, "Ignoring found " << PYMOLECUILDER_MODULE_NAME << " import, but keeping AS name " << moduleName << ".");
        } else {
        	ELOG(2, "Ignoring found " << PYMOLECUILDER_MODULE_NAME << " import.");
        }
      } else {
        buffer_import << current_line << std::endl;
      }
    } else {
      buffer_else << current_line << std::endl;
    }
  }
  std::string pythonscript_import( std::istreambuf_iterator<char>(buffer_import),
      (std::istreambuf_iterator<char>()) );
  std::string pythonscript_else( std::istreambuf_iterator<char>(buffer_else),
      (std::istreambuf_iterator<char>()) );

  try {
#ifdef HAVE_PYTHON2
    PyImport_AppendInittab( PYMOLECUILDER_MODULE_NAME.c_str(), &initpyMoleCuilder );
#else
    PyImport_AppendInittab( PYMOLECUILDER_MODULE_NAME.c_str(), &PyInit_pyMoleCuilder );
#endif

    Py_Initialize();

    boost::python::object main_module((
        boost::python::handle<>(boost::python::borrowed(PyImport_AddModule("__main__")))));

    boost::python::object main_namespace = main_module.attr("__dict__");

    boost::python::handle<> imported(( PyRun_String( pythonscript_import.c_str(),
        Py_file_input,
        main_namespace.ptr(),
        main_namespace.ptr() ) ));

    boost::python::object molecuilder_module( (boost::python::handle<>(PyImport_ImportModule("pyMoleCuilder"))) );
    main_namespace[PYMOLECUILDER_MODULE_NAME] = molecuilder_module;
    if (moduleName.size() > 0)
        main_namespace[moduleName] = molecuilder_module;

    std::string enveloped_script("print(\"BEGIN of "+python_scripttitle+":\")\n");
    enveloped_script += pythonscript_else+std::string("\n");
    enveloped_script += std::string("print(\"END of "+python_scripttitle+":\")\n");

    boost::python::handle<> ignored(( PyRun_String( enveloped_script.c_str(),
        Py_file_input,
        main_namespace.ptr(),
        main_namespace.ptr() ) ));

  } catch( boost::python::error_already_set ) {
    PyErr_Print();
    return false;
  }
  return true;
}