import subprocess
import shlex
import re
from pathlib import Path
from typing import Literal

_marc_version = '2023.2'
_marc_root = '/opt/msc'
_damask_root = str(Path(__file__).parents[3])

class Marc:
    """Wrapper to run DAMASK with MSC Marc."""

    def __init__(self,
                 version: str = _marc_version,
                 marc_root: str = _marc_root,
                 damask_root: str = _damask_root):
        """
        Create a Marc solver object.

        Parameters
        ----------
        version : str, optional
            Marc version. Defaults to latest supported Marc version.
        marc_root : str, optional
            Marc root location. Defaults to /opt/msc.
        damask_root : str, optional
            DAMASK root location.
            Default is autodected based on location of the Python library.

        """
        self.marc_version = version
        self.marc_root = Path(marc_root)
        self.damask_root = Path(damask_root)

    @property
    def library_path(self):

        path_lib = self.marc_root/f'mentat{self.marc_version}/shlib/linux64'
        if not path_lib.is_dir():
            raise FileNotFoundError(f'library path "{path_lib}" not found')

        return path_lib


    @property
    def tools_path(self):

        path_tools = self.marc_root/f'marc{self.marc_version}/tools'
        if not path_tools.is_dir():
            raise FileNotFoundError(f'tools path "{path_tools}" not found')

        return path_tools


    def submit_job(self, model: str, job: str,
                   compile: bool = False,
                   optimization: Literal['', 'l', 'h'] = '',
                   env = None):
        """
        Assemble command line arguments and call Marc executable.

        Parameters
        ----------
        model : str
            Name of model.
        job : str
            Name of job.
        compile : bool, optional
            Compile DAMASK_Marc user subroutine (and save for future use).
            Defaults to False.
        optimization : {'', 'l', 'h'}, optional
            Optimization level '': -O0, 'l': -O1, or 'h': -O3.
            Defaults to ''.
        env : dict, optional
            Environment for execution.

        """
        usersub = (self.damask_root/'src/Marc/DAMASK_Marc').with_suffix('.f90' if compile else '.marc')
        if not usersub.is_file():
            raise FileNotFoundError(f'subroutine ({"source" if compile else "binary"}) "{usersub}" not found')

        # Define options [see Marc Installation and Operation Guide, pp 23]
        script = f'run_damask_{optimization}mp'

        cmd = f'{self.tools_path/script} -jid {model}_{job} -nprocd 1 -autorst 0 -ci n -cr n -dcoup 0 -b no -v no ' \
            + (f'-u {usersub} -save y' if compile else f'-prog {usersub.with_suffix("")}')
        print(cmd)

        ret = subprocess.run(shlex.split(cmd),capture_output=True,env=env)

        if (m := re.search('Exit number ([0-9]+)',ret.stderr.decode())) is not None:
            if 3004 != (v := int(m.group(1))):
                print(ret.stderr.decode())
                print(ret.stdout.decode())
                raise RuntimeError(f'Marc simulation failed ({v})')
        else:
            print(ret.stderr.decode())
            print(ret.stdout.decode())
            raise RuntimeError('Marc simulation failed (unknown return value)')