# Copyright (C) 2012  Alex Nitz, Josh Willis
#
# 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
#
# =============================================================================
#
"""PyCBC contains a toolkit for CBC gravitational wave analysis

"""
import subprocess, os, sys, tempfile
import logging
import signal

try:
    # This will fail when pycbc is imported during the build process,
    # before version.py has been generated.
    from version import git_hash
    from version import version as pycbc_version
except:
    git_hash = 'none'
    pycbc_version = 'none'

def init_logging(verbose=False):
    """
    Common utility for setting up logging in PyCBC. Installs a signal handler
    such that verbosity can be activated at run-time by sending a SIGUSR1 to
    the process.
    """
    def sig_handler(signum, frame):
        logger = logging.getLogger()
        log_level = logger.level
        if log_level == logging.DEBUG:
            log_level = logging.WARN
        else:
            log_level = logging.DEBUG
        logging.warn('Got signal %d, setting log level to %d',
                     signum, log_level)
        logger.setLevel(log_level)

    signal.signal(signal.SIGUSR1, sig_handler)

    if verbose:
        initial_level = logging.DEBUG
    else:
        initial_level = logging.WARN
    logging.basicConfig(format='%(asctime)s %(message)s', level=initial_level)


# Check for optional components of the PyCBC Package
try:
    # This is a crude check to make sure that the driver is installed
    try:
        err = subprocess.call(["nvidia-smi"], stdout=open(os.devnull, 'wb'), stderr=open(os.devnull, 'wb'))
        if err != 0:
            raise ImportError("Cannot access 'nvidia-smi', driver may not be installed correctly")
    except OSError:
        pass

    # Check that pycuda is installed and can talk to the driver
    import pycuda.driver as _pycudadrv

    HAVE_CUDA=True 
except ImportError:
    HAVE_CUDA=False
    
# Check for openmp suppport, currently we pressume it exists, unless on 
# platforms (mac) that are silly and don't use the standard gcc. 
if sys.platform == 'darwin':
    HAVE_OMP = False
else:
    HAVE_OMP = True

# PyCBC-Specific Constants

# Set the value we want any aligned memory calls to use
# N.B.: *Not* all pycbc memory will be aligned to multiples
# of this value

PYCBC_ALIGNMENT = 32

# Dynamic range factor: a large constant for rescaling
# GW strains.  This is 2**69 rounded to 17 sig.fig.

DYN_RANGE_FAC =  5.9029581035870565e+20


# Make sure we use a user specific, machine specific compiled cache location
_python_name =  "python%d%d_compiled" % tuple(sys.version_info[:2])
_tmp_dir = tempfile.gettempdir()
_cache_dir_name = repr(os.getuid()) + '_' + _python_name
_cache_dir_path = os.path.join(_tmp_dir, _cache_dir_name)
# Append the git hash to the cache path.  This will ensure that cached 
# files are correct even in cases where weave currently doesn't realize
# that a recompile is needed.
# FIXME: It would be better to find a way to trigger a recompile off
# of all the arguments to weave.
_cache_dir_path = os.path.join(_cache_dir_path, pycbc_version)
_cache_dir_path = os.path.join(_cache_dir_path, git_hash)
try: os.makedirs(_cache_dir_path)
except OSError: pass
os.environ['PYTHONCOMPILED'] = _cache_dir_path

# Check for MKL capability
try:
    import pycbc.fft.mkl
    HAVE_MKL=True
except ImportError as e:
    print e
    HAVE_MKL=False