"""Parallel workflow execution via LSF
"""

import os

from .base import (SGELikeBatchManagerBase, logger, iflogger, logging)

from nipype.interfaces.base import CommandLine

from time import sleep

import re


class LSFPlugin(SGELikeBatchManagerBase):
    """Execute using LSF Cluster Submission

    The plugin_args input to run can be used to control the LSF execution.
    Currently supported options are:

    - template : template to use for batch job submission
    - bsub_args : arguments to be prepended to the job execution script in the
                  bsub call

    """

    def __init__(self, **kwargs):
        template = """
#$ -S /bin/sh
        """
        self._retry_timeout = 2
        self._max_tries = 2
        self._bsub_args = ''
        if 'plugin_args' in kwargs and kwargs['plugin_args']:
            if 'retry_timeout' in kwargs['plugin_args']:
                self._retry_timeout = kwargs['plugin_args']['retry_timeout']
            if  'max_tries' in kwargs['plugin_args']:
                self._max_tries = kwargs['plugin_args']['max_tries']
        super(LSFPlugin, self).__init__(template, **kwargs)

    def _is_pending(self, taskid):
        """LSF lists a status of 'PEND' when a job has been submitted but is waiting to be picked up,
        and 'RUN' when it is actively being processed. But _is_pending should return True until a job has
        finished and is ready to be checked for completeness. So return True if status is either 'PEND'
        or 'RUN'"""
        cmd = CommandLine('bjobs',
                          terminal_output='allatonce')
        cmd.inputs.args = '%d' % taskid
        # check lsf task
        oldlevel = iflogger.level
        iflogger.setLevel(logging.getLevelName('CRITICAL'))
        result = cmd.run(ignore_exception=True)
        iflogger.setLevel(oldlevel)
        # logger.debug(result.runtime.stdout)
        if 'PEND' in result.runtime.stdout or 'RUN' in result.runtime.stdout:
            return True
        else:
            return False

    def _submit_batchtask(self, scriptfile, node):
        cmd = CommandLine('bsub', environ=os.environ.data,
                          terminal_output='allatonce')
        path = os.path.dirname(scriptfile)
        bsubargs = ''
        if self._bsub_args:
            bsubargs = self._bsub_args
        if 'bsub_args' in node.plugin_args:
            if 'overwrite' in node.plugin_args and\
               node.plugin_args['overwrite']:
                bsubargs = node.plugin_args['bsub_args']
            else:
                bsubargs += (" " + node.plugin_args['bsub_args'])
        if '-o' not in bsubargs:  # -o outfile
            bsubargs = '%s -o %s' % (bsubargs, path)
        if '-e' not in bsubargs:
            bsubargs = '%s -e %s' % (bsubargs, path)  # -e error file
        if node._hierarchy:
            jobname = '.'.join((os.environ.data['LOGNAME'],
                                node._hierarchy,
                                node._id))
        else:
            jobname = '.'.join((os.environ.data['LOGNAME'],
                                node._id))
        jobnameitems = jobname.split('.')
        jobnameitems.reverse()
        jobname = '.'.join(jobnameitems)
        cmd.inputs.args = '%s -J %s sh %s' % (bsubargs,
                                              jobname,
                                              scriptfile)  # -J job_name_spec
        logger.debug('bsub ' + cmd.inputs.args)
        oldlevel = iflogger.level
        iflogger.setLevel(logging.getLevelName('CRITICAL'))
        tries = 0
        while True:
            try:
                result = cmd.run()
            except Exception, e:
                if tries < self._max_tries:
                    tries += 1
                    sleep(
                        self._retry_timeout)  # sleep 2 seconds and try again.
                else:
                    iflogger.setLevel(oldlevel)
                    raise RuntimeError('\n'.join((('Could not submit lsf task'
                                                   ' for node %s') % node._id,
                                                  str(e))))
            else:
                break
        iflogger.setLevel(oldlevel)
        # retrieve lsf taskid
        match = re.search('<(\d*)>', result.runtime.stdout)
        if match:
            taskid = int(match.groups()[0])
        else:
            raise ScriptError("Can't parse submission job output id: %s" %
                              result.runtime.stdout)
        self._pending[taskid] = node.output_dir()
        logger.debug('submitted lsf task: %d for node %s' % (taskid, node._id))
        return taskid
