import sys
import shutil
import argparse
import logging
import configparser

from time import time
from datetime import timedelta

from pathlib import Path

from .grafana import Silencer
from .stl import copy_stl
from .run import run


_t0 = time()
parser = argparse.ArgumentParser(
    prog='run',
    description='Run the OpenFoam simulation',
)
parser.add_argument('-c', '--config', default='config.ini', type=Path,
    help='Configuration file')
parser.add_argument('-l', '--log-level', default='INFO', type=str,
    help='Log level')

args = parser.parse_args()

config = configparser.ConfigParser()
config.read(args.config)

logging.basicConfig(
    filename=config.get('main', 'log_file', fallback=None),
    level=args.log_level
)
log = logging.getLogger('openfoam')

log.info('Starting program')


if config.getboolean('grafana', 'pause', fallback=False):
    log.info('Silencing Grafana alert')
    grafana = Silencer(
        url=config.get('grafana', 'url'),
        apikey=config.get('grafana', 'apikey'),
    )
    grafana.silence_alert()

input_dir = Path(config.get('main', 'input_dir'), config.get('main', 'case'))\
    .expanduser()
work_dir = Path(config.get('main', 'work_dir')).expanduser()

if not work_dir.exists():
    log.error(f'Work directory ({work_dir}) not found')
    sys.exit(1)
    
case_dir = work_dir.joinpath(config.get('main', 'case'))
if case_dir.exists():
    log.info(f'Deleting case ({case_dir})')
    shutil.rmtree(case_dir)

log.info(f'Copying case ({input_dir} -> {case_dir})')
shutil.copytree(input_dir, case_dir)


def step(command, alias=None):
    if alias == None: alias = command
    log.info(f'Running {alias}')
    code = run(command, case_dir, alias)
    if code != 0:
        log.error(f'{alias} failed')
        sys.exit(code)
    log.info(f'{alias} finished successfully')


if config.getboolean('stl', 'copy', fallback=False):
    stl_in = Path(config.get('stl', 'from')).expanduser()
    if not stl_in.exists():
        log.error(f'STL from directory does not exist ({stl_in})')
        sys.exit(1)

    log.info(f'Copying stl directory ({stl_in})')
    copy_stl(stl_in, case_dir)

if config.getboolean('blockMesh', 'enable', fallback=False):
    step(('blockMesh'))

if config.getboolean('snappyHexMesh', 'enable', fallback=False):
    step(('snappyHexMesh', '-overwrite'), 'snappyHexMesh')

log.info('Copying 0.org -> 0')
shutil.copytree(
    case_dir.joinpath('0.org'),
    case_dir.joinpath('0'),
)

if config.getboolean('setFields', 'enable', fallback=False):
    step(('setFields'))

if config.getboolean('olaFlow', 'enable', fallback=False):
    cmd = ('olaFlow')
    if config.getboolean('parallel', 'enable', fallback=False):
        cmd = (
            'mpirun',
            '-np', config.get('parallel', 'threads'),
            'olaFlow', '-parallel'
        )
        step(('decomposePar'))

    step(cmd, 'olaFlow')

    if config.getboolean('parallel', 'enable', fallback=False) \
            and config.getboolean('reconstructPar', 'enable', fallback=False):
        step(('reconstructPar'))

        log.info(f'Deleting processor directories')
        for proc_dir in case_dir.glob(r'processor*'):
            log.info(f'Deleting {proc_dir}')
            shutil.rmtree(proc_dir)

if config.getboolean('grafana', 'pause', fallback=False):
    log.info('Unsilencing Grafana alert')
    grafana.unsilence_alert()

_t1 = time()
log.info(f'Program ended successfully after {timedelta(seconds=_t1-_t0)}')