# Copyright (C) 2015  Ian Harry, Alex Nitz
#
# This program 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 3 of the License, or (at your
# option) any later version.
#
# This program 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 this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

#
# =============================================================================
#
#                                   Preamble
#
# =============================================================================
#
"""
This module is responsible for setting up the part of a pycbc workflow that
will generate the injection files to be used for assessing the workflow's
ability to detect predicted signals.
Full documentation for this module can be found here:
https://ldas-jobs.ligo.caltech.edu/~cbc/docs/pycbc/NOTYETCREATED.html
"""

import logging
import os.path
import configparser as ConfigParser
from pycbc.workflow.core import FileList, make_analysis_dir, Node
from pycbc.workflow.core import Executable, resolve_url_to_file
from pycbc.workflow.jobsetup import (LalappsInspinjExecutable,
        PycbcCreateInjectionsExecutable, select_generic_executable)

def veto_injections(workflow, inj_file, veto_file, veto_name, out_dir, tags=None):
    tags = [] if tags is None else tags
    make_analysis_dir(out_dir)

    node = Executable(workflow.cp, 'strip_injections', ifos=workflow.ifos,
                          out_dir=out_dir, tags=tags).create_node()
    node.add_opt('--segment-name', veto_name)
    node.add_input_opt('--veto-file', veto_file)
    node.add_input_opt('--injection-file', inj_file)
    node.add_opt('--ifos', ' '.join(workflow.ifos))
    node.new_output_file_opt(workflow.analysis_time, '.xml', '--output-file')
    workflow += node
    return node.output_files[0]


class PyCBCOptimalSNRExecutable(Executable):
    """Compute optimal SNR for injections"""
    current_retention_level = Executable.ALL_TRIGGERS

    def create_node(self, workflow, inj_file, precalc_psd_files, group_str):
        node = Node(self)
        _, ext = os.path.splitext(inj_file.name)
        node.add_input_opt('--input-file', inj_file)
        node.add_opt('--injection-fraction-range', group_str)
        node.add_input_list_opt('--time-varying-psds', precalc_psd_files)
        node.new_output_file_opt(workflow.analysis_time, ext,
                                 '--output-file')
        return node


class PyCBCMergeHDFExecutable(Executable):
    """Merge HDF injection files executable class"""
    current_retention_level = Executable.MERGED_TRIGGERS

    def create_node(self, workflow, input_files):
        node = Node(self)
        node.add_input_list_opt('--injection-files', input_files)
        node.new_output_file_opt(workflow.analysis_time, '.hdf',
                                 '--output-file')
        return node


def compute_inj_optimal_snr(workflow, inj_file, precalc_psd_files, out_dir,
                            tags=None):
    "Set up a job for computing optimal SNRs of a sim_inspiral file."
    if tags is None:
        tags = []

    try:
        factor = int(workflow.cp.get_opt_tags('workflow-optimal-snr',
                                              'parallelization-factor',
                                              tags))
    except Exception as e:
        logging.warning(e)
        factor = 1

    if factor == 1:
        # parallelization factor not given - default to single optimal snr job
        opt_snr_exe = PyCBCOptimalSNRExecutable(workflow.cp, 'optimal_snr',
                                                ifos=workflow.ifos,
                                                out_dir=out_dir, tags=tags)
        node = opt_snr_exe.create_node(workflow, inj_file,
                                       precalc_psd_files, '0/1')
        workflow += node

        return node.output_files[0]

    opt_snr_split_files = []
    for i in range(factor):
        group_str = '%s/%s' % (i, factor)
        opt_snr_exe = PyCBCOptimalSNRExecutable(workflow.cp, 'optimal_snr',
                                                ifos=workflow.ifos,
                                                out_dir=out_dir,
                                                tags=tags + [str(i)])
        opt_snr_exe.update_current_retention_level(
            Executable.INTERMEDIATE_PRODUCT)
        node = opt_snr_exe.create_node(workflow, inj_file, precalc_psd_files,
                                       group_str)
        opt_snr_split_files += [node.output_files[0]]
        workflow += node

    hdfcombine_exe = PyCBCMergeHDFExecutable(
        workflow.cp,
        'optimal_snr_merge',
        ifos=workflow.ifos,
        out_dir=out_dir,
        tags=tags
    )

    hdfcombine_node = hdfcombine_exe.create_node(
        workflow,
        opt_snr_split_files
    )
    workflow += hdfcombine_node

    return hdfcombine_node.output_files[0]

def cut_distant_injections(workflow, inj_file, out_dir, tags=None):
    "Set up a job for removing injections that are too distant to be seen"
    if tags is None:
        tags = []

    node = Executable(workflow.cp, 'inj_cut', ifos=workflow.ifos,
                      out_dir=out_dir, tags=tags).create_node()
    node.add_input_opt('--input', inj_file)
    node.new_output_file_opt(workflow.analysis_time, '.xml', '--output-file')
    workflow += node
    return node.output_files[0]

def inj_to_hdf(workflow, inj_file, out_dir, tags=None):
    """ Convert injection file to hdf format if not already one
    """
    _, ext = os.path.splitext(inj_file.name)
    if ext == '.hdf':
        return inj_file

    if tags is None:
        tags = []

    node = Executable(workflow.cp, 'inj2hdf', ifos=workflow.ifos,
                      out_dir=out_dir, tags=tags).create_node()
    node.add_input_opt('--injection-file', inj_file)
    node.new_output_file_opt(workflow.analysis_time, '.hdf', '--output-file')
    workflow += node
    return node.output_file

def setup_injection_workflow(workflow, output_dir=None,
                             inj_section_name='injections', tags=None):
    """
    This function is the gateway for setting up injection-generation jobs in a
    workflow. It should be possible for this function to support a number
    of different ways/codes that could be used for doing this, however as this
    will presumably stay as a single call to a single code (which need not be
    inspinj) there are currently no subfunctions in this moudle.

    Parameters
    -----------
    workflow : pycbc.workflow.core.Workflow
        The Workflow instance that the coincidence jobs will be added to.
    output_dir : path
        The directory in which injection files will be stored.
    inj_section_name : string (optional, default='injections')
        The string that corresponds to the option describing the exe location
        in the [executables] section of the .ini file and that corresponds to
        the section (and sub-sections) giving the options that will be given to
        the code at run time.
    tags : list of strings (optional, default = [])
        A list of the tagging strings that will be used for all jobs created
        by this call to the workflow. This will be used in output names.

    Returns
    --------
    inj_files : pycbc.workflow.core.FileList
        The list of injection files created by this call.
    inj_tags : list of strings
        The tag corresponding to each injection file and used to uniquely
        identify them. The FileList class contains functions to search
        based on tags.
    """
    if tags is None:
        tags = []
    logging.info("Entering injection module.")
    make_analysis_dir(output_dir)

    # Get full analysis segment for output file naming
    full_segment = workflow.analysis_time

    # Identify which injections to do by presence of sub-sections in
    # the configuration file
    inj_tags = []
    inj_files = FileList([])

    for section in  workflow.cp.get_subsections(inj_section_name):
        inj_tag = section.upper()
        curr_tags = tags + [inj_tag]

        # Parse for options in ini file
        injection_method = workflow.cp.get_opt_tags("workflow-injections",
                                                    "injections-method",
                                                    curr_tags)

        if injection_method in ["IN_WORKFLOW", "AT_RUNTIME"]:
            exe = select_generic_executable(workflow, 'injections')
            inj_job = exe(workflow.cp, inj_section_name,
                          out_dir=output_dir, ifos='HL',
                          tags=curr_tags)
            if exe is PycbcCreateInjectionsExecutable:
                config_url = workflow.cp.get('workflow-injections',
                                             section+'-config-file')
                config_file = resolve_url_to_file(config_url)
                node, inj_file = inj_job.create_node(config_file)
            else:
                node = inj_job.create_node(full_segment)
            if injection_method == "AT_RUNTIME":
                workflow.execute_node(node)
            else:
                workflow.add_node(node)
            inj_file = node.output_files[0]
            inj_files.append(inj_file)
        elif injection_method == "PREGENERATED":
            file_attrs = {
                'ifos': ['HL'],
                'segs': full_segment,
                'tags': curr_tags
            }
            injection_path = workflow.cp.get_opt_tags(
                "workflow-injections",
                "injections-pregenerated-file",
                curr_tags
            )
            curr_file = resolve_url_to_file(injection_path, attrs=file_attrs)
            inj_files.append(curr_file)
        else:
            err = "Injection method must be one of IN_WORKFLOW, "
            err += "AT_RUNTIME or PREGENERATED. Got %s." % (injection_method)
            raise ValueError(err)

        inj_tags.append(inj_tag)

    logging.info("Leaving injection module.")
    return inj_files, inj_tags
