# -*- coding: utf-8 -*-
"""Run objsim simulations from python.  
"""

import os
import subprocess
import shutil
class ObjsimRunner(object):
    
    """Run objsim simulations from python.
    """
    
    def __init__(self, binary):
        self.binary = binary
        self.working_dir = os.path.dirname(self.binary)
        self.process = None
        
    def run(self, datadir, fname_default_settings, mod_settings):
        """Run objsim simulation.
        
        Args:
        datadir: dir for simulation data
        fname_default_settings: file name for .cfg file with default settings
        mod_settings: list with modifications to default settings (see example) 
        
        Example:
          >>> from objsimpy.config import SIMDATA_BASE_DIR, OBJSIM_DIR
          >>> datadir = os.path.join(SIMDATA_BASE_DIR, 'csim', 'som02', 'tune_map_0')
          >>> changed_settings = ['--NTrials', '2',
                                  '--NSteps', '50',
                                  '--StimFileName', 'gauss20x20'
                                  ]
          >>> som02_binary = os.path.join(OBJSIM_DIR, 'install', 'bin', 'som02', 'som02')
          >>> som02 = ObjsimRunner(som02_binary)
          >>> som02.run(datadir, default_settings_file, changed_settings)
        """
        if not os.path.isdir(datadir):
            os.mkdir(datadir)
        self.datadir = datadir
        fname_settings = os.path.join(self.working_dir, 'settings_' + os.path.basename(self.binary) + '.cfg')
        shutil.copy(fname_default_settings, fname_settings)
        fname_outfile = os.path.join(datadir, 'output.txt')
        fname_errfile = os.path.join(datadir, 'error.txt')
        with open(fname_outfile, 'w') as fout, open(fname_errfile, 'w') as ferr:
            cmd = [self.binary, 
                   '--DataDirectory', datadir]
            cmd += mod_settings
            self.process = subprocess.Popen(cmd, stdout=fout, stderr=ferr, cwd=self.working_dir)
    
    def is_running(self):
        return self.process.poll() is None
            
    def stop(self):
        """Kill simulation."""
        self.process.kill()