# Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# pylint: disable=invalid-name, too-few-public-methods
# pylint: disable=too-many-instance-attributes

"""NetCDF building block"""

from __future__ import absolute_import
from __future__ import unicode_literals
from __future__ import print_function

import logging # pylint: disable=unused-import
import os
from copy import copy as _copy

import hpccm.config

from hpccm.building_blocks.packages import packages
from hpccm.common import linux_distro
from hpccm.primitives.comment import comment
from hpccm.primitives.copy import copy
from hpccm.primitives.environment import environment
from hpccm.primitives.shell import shell
from hpccm.templates.ConfigureMake import ConfigureMake
from hpccm.templates.ldconfig import ldconfig
from hpccm.templates.rm import rm
from hpccm.templates.tar import tar
from hpccm.templates.wget import wget
from hpccm.toolchain import toolchain

class netcdf(ConfigureMake, ldconfig, rm, tar, wget):
    """NetCDF building block"""

    def __init__(self, **kwargs):
        """The `netcdf` building block downloads, configures, builds, and
        installs the
        [NetCDF](https://www.unidata.ucar.edu/software/netcdf/)
        component.

        The [HDF5](#hdf5) building block should be installed prior to
        this building block.

        As a side effect, this building block modifies `PATH`
        to include the NetCDF build.

        # Parameters

        check: Boolean flag to specify whether the `make check` step
        should be performed.  The default is False.

        configure_opts: List of options to pass to `configure`.  The
        default value is an empty list.

        cxx: Boolean flag to specify whether the NetCDF C++ library
        should be installed.  The default is True.

        fortran: Boolean flag to specify whether the NetCDF Fortran
        library should be installed.  The default is True.

        hdf5_dir: Path to the location where HDF5 is installed in the
        container image.  The default value is `/usr/local/hdf5`.

        ldconfig: Boolean flag to specify whether the NetCDF library
        directory should be added dynamic linker cache.  If False, then
        `LD_LIBRARY_PATH` is modified to include the NetCDF library
        directory. The default value is False.

        ospackages: List of OS packages to install prior to
        configuring and building.  For Ubuntu, the default values are
        `ca-certificates`, `file`, `libcurl4-openssl-dev`, `m4`,
        `make`, `wget`, and `zlib1g-dev`.  For RHEL-based Linux
        distributions the default values are `ca-certificates`,
        `file`, `libcurl-devel` `m4`, `make`, `wget`, and
        `zlib-devel`.

        prefix: The top level install location.  The default location
        is `/usr/local/netcdf`.

        toolchain: The toolchain object.  This should be used if
        non-default compilers or other toolchain options are needed.
        The default is empty.

        version: The version of NetCDF to download.  The default value
        is `4.6.1`.

        version_cxx: The version of NetCDF C++ to download.  The
        default value is `4.3.0`.

        version_fortran: The version of NetCDF Fortran to download.
        The default value is `4.4.4`.

        # Examples

        ```python
        netcdf(prefix='/opt/netcdf/4.6.1', version='4.6.1')
        ```

        ```python
        p = pgi(eula=True)
        netcdf(toolchain=p.toolchain)
        ```
        """

        # Trouble getting MRO with kwargs working correctly, so just call
        # the parent class constructors manually for now.
        #super(netcdf, self).__init__(**kwargs)
        ConfigureMake.__init__(self, **kwargs)
        ldconfig.__init__(self, **kwargs)
        rm.__init__(self, **kwargs)
        tar.__init__(self, **kwargs)
        wget.__init__(self, **kwargs)

        self.configure_opts = kwargs.get('configure_opts', [])

        self.__baseurl = 'https://www.unidata.ucar.edu/downloads/netcdf/ftp'
        self.__check = kwargs.get('check', False)
        self.__cxx = kwargs.get('cxx', True)
        self.__fortran = kwargs.get('fortran', True)
        self.__hdf5_dir = kwargs.get('hdf5_dir', '/usr/local/hdf5')
        self.__ospackages = kwargs.get('ospackages', [])
        self.prefix = kwargs.get('prefix', '/usr/local/netcdf')
        self.__runtime_ospackages = [] # Filled in by __distro()
        self.__toolchain = kwargs.get('toolchain', toolchain())
        self.__version = kwargs.get('version', '4.6.1')
        self.__version_cxx = kwargs.get('version_cxx', '4.3.0')
        self.__version_fortran = kwargs.get('version_fortran', '4.4.4')
        self.__wd = '/var/tmp'

        self.__commands = [] # Filled in by __setup()
        self.__environment_variables = {
            'PATH': '{}:$PATH'.format(os.path.join(self.prefix, 'bin'))}

        # Set the Linux distribution specific parameters
        self.__distro()

        # C interface (required)
        self.__setup()

        # C++ interface (optional)
        if self.__cxx:
            self.__setup_optional(pkg='netcdf-cxx4',
                                  version=self.__version_cxx)

        # Fotran interface (optional)
        if self.__fortran:
            self.__setup_optional(pkg='netcdf-fortran',
                                  version=self.__version_fortran)

    def __str__(self):
        """String representation of the building block"""

        instructions = []

        comments = ['NetCDF version {}'.format(self.__version)]
        if self.__cxx:
            comments.append('NetCDF C++ version {}'.format(self.__version_cxx))
        if self.__fortran:
            comments.append('NetCDF Fortran version {}'.format(self.__version_fortran))
        instructions.append(comment(', '.join(comments)))

        if self.__ospackages:
            instructions.append(packages(ospackages=self.__ospackages))

        instructions.append(shell(commands=self.__commands))

        if self.__environment_variables:
            instructions.append(environment(
                variables=self.__environment_variables))

        return '\n'.join(str(x) for x in instructions)

    def __distro(self):
        """Based on the Linux distribution, set values accordingly.  A user
        specified value overrides any defaults."""

        if hpccm.config.g_linux_distro == linux_distro.UBUNTU:
            if not self.__ospackages:
                self.__ospackages = ['ca-certificates', 'file',
                                     'libcurl4-openssl-dev', 'm4', 'make',
                                     'wget', 'zlib1g-dev']
            self.__runtime_ospackages = ['zlib1g']
        elif hpccm.config.g_linux_distro == linux_distro.CENTOS:
            if not self.__ospackages:
                self.__ospackages = ['ca-certificates', 'file',
                                     'libcurl-devel', 'm4', 'make',
                                     'wget', 'zlib-devel']
            self.__runtime_ospackages = ['zlib']
        else: # pragma: no cover
            raise RuntimeError('Unknown Linux distribution')

    def __setup(self):
        """Construct the series of shell commands, i.e., fill in
           self.__commands"""

        # Create a copy of the toolchain so that it can be modified
        # without impacting the original.
        toolchain = _copy(self.__toolchain)

        # Need to tell it where to find HDF5
        if not toolchain.CPPFLAGS:
            toolchain.CPPFLAGS = '-I{}/include'.format(self.__hdf5_dir)
        if not toolchain.LDFLAGS:
            toolchain.LDFLAGS = '-L{}/lib'.format(self.__hdf5_dir)

        tarball = 'netcdf-{}.tar.gz'.format(self.__version)
        url = '{0}/{1}'.format(self.__baseurl, tarball)

        # Download source from web
        self.__commands.append(self.download_step(url=url,
                                                  directory=self.__wd))
        self.__commands.append(self.untar_step(
            tarball=os.path.join(self.__wd, tarball), directory=self.__wd))

        self.__commands.append(self.configure_step(
            directory=os.path.join(self.__wd,
                                   'netcdf-{}'.format(self.__version)),
            toolchain=toolchain))

        self.__commands.append(self.build_step())

        # Check the build
        if self.__check:
            self.__commands.append(self.check_step())

        self.__commands.append(self.install_step())

        # Set library path
        libpath = os.path.join(self.prefix, 'lib')
        if self.ldconfig:
            self.__commands.append(self.ldcache_step(directory=libpath))
        else:
            self.__environment_variables['LD_LIBRARY_PATH'] = '{}:$LD_LIBRARY_PATH'.format(libpath)

        self.__commands.append(self.cleanup_step(
            items=[os.path.join(self.__wd, tarball),
                   os.path.join(self.__wd,
                                'netcdf-{}'.format(self.__version))]))

    def __setup_optional(self, pkg='', version=''):
        # Create a copy of the toolchain so that it can be modified
        # without impacting the original.
        toolchain = _copy(self.__toolchain)

        # Need to tell it where to find NetCDF
        if not toolchain.CPPFLAGS:
            toolchain.CPPFLAGS = '-I{}/include'.format(self.prefix)
        if not toolchain.LDFLAGS:
            toolchain.LDFLAGS = '-L{}/lib'.format(self.prefix)
        if not toolchain.LD_LIBRARY_PATH:
            toolchain.LD_LIBRARY_PATH = '{}/lib:$LD_LIBRARY_PATH'.format(self.prefix)

        tarball = '{0}-{1}.tar.gz'.format(pkg, version)
        url = '{0}/{1}'.format(self.__baseurl, tarball)

        # Download source from web
        self.__commands.append(self.download_step(url=url,
                                                  directory=self.__wd))
        self.__commands.append(self.untar_step(
            tarball=os.path.join(self.__wd, tarball), directory=self.__wd))

        self.__commands.append(self.configure_step(
            directory=os.path.join(self.__wd,
                                   '{0}-{1}'.format(pkg, version)),
            toolchain=toolchain))

        self.__commands.append(self.build_step())

        # Check the build
        if self.__check:
            # Checks fail when using parallel make.  Disable it
            # temporarily.
            _parallel = self.parallel
            self.parallel = 1
            self.__commands.append(self.check_step())
            self.parallel = _parallel

        self.__commands.append(self.install_step())

        self.__commands.append(self.cleanup_step(
            items=[os.path.join(self.__wd, tarball),
                   os.path.join(self.__wd,
                                '{0}-{1}'.format(pkg, version))]))

    def runtime(self, _from='0'):
        """Generate the set of instructions to install the runtime specific
        components from a build in a previous stage.

        # Examples

        ```python
        n = netcdf(...)
        Stage0 += n
        Stage1 += n.runtime()
        ```
        """
        instructions = []
        instructions.append(comment('NetCDF'))
        instructions.append(packages(ospackages=self.__runtime_ospackages))
        instructions.append(copy(_from=_from, src=self.prefix,
                                 dest=self.prefix))
        if self.ldconfig:
            instructions.append(shell(
                commands=[self.ldcache_step(
                    directory=os.path.join(self.prefix, 'lib'))]))
        if self.__environment_variables:
            instructions.append(environment(
                variables=self.__environment_variables))
        return '\n'.join(str(x) for x in instructions)
