# Copyright 2013-2023 Lawrence Livermore National Security, LLC and other
# Spack Project Developers. See the top-level COPYRIGHT file for details.
#
# SPDX-License-Identifier: (Apache-2.0 OR MIT)

from spack.package import *
from spack.pkg.builtin.boost import Boost


class Channelflow(CMakePackage):
    """Channelflow is a software system for numerical analysis of the
    incompressible fluid flow in channel geometries, written in C++.
    """

    homepage = "https://github.com/epfl-ecps/channelflow"
    git = "https://github.com/epfl-ecps/channelflow.git"

    license("GPL-2.0-only")

    version("master", branch="master")

    variant("shared", default=True, description="Build shared libs")
    variant("mpi", default=True, description="Enable MPI parallelism")
    variant("hdf5", default=True, description="Enable support for HDF5 I/O")
    variant(
        "netcdf",
        default="serial",
        values=("none", "serial", "parallel"),
        multi=False,
        description="Level of support for NetCDF I/O",
    )
    variant("python", default=False, description="Build python bindings")

    depends_on("eigen")
    depends_on("fftw")

    # MPI related constraints
    depends_on("mpi", when="+mpi")
    depends_on("fftw+mpi", when="+mpi")

    # Support for different I/O formats
    depends_on("hdf5+cxx", when="+hdf5")
    depends_on("netcdf-c", when="netcdf=serial")
    depends_on("netcdf-c+mpi", when="netcdf=parallel")

    # Python bindings
    depends_on("boost+python", when="+python")

    # TODO: replace this with an explicit list of components of Boost,
    # for instance depends_on('boost +filesystem')
    # See https://github.com/spack/spack/pull/22303 for reference
    depends_on(Boost.with_default_variants, when="+python")

    conflicts("~mpi", when="netcdf=parallel", msg="Parallel NetCDF requires MPI")
    conflicts(
        "+mpi", when="+python", msg="Building python bindings is possible only for the serial code"
    )
    conflicts("~mpi", when="^mpi", msg="There should be no MPI in the DAG when ~mpi is active")

    def cmake_args(self):
        spec = self.spec

        on_or_off = lambda predicate: "ON" if predicate else "OFF"

        args = [
            "-DBUILD_SHARED_LIBS:BOOL={0}".format(on_or_off("+shared" in spec)),
            "-DUSE_MPI:BOOL={0}".format(on_or_off("+mpi" in spec)),
            "-DWITH_HDF5CXX:BOOL={0}".format(on_or_off("+hdf5" in spec)),
            "-DWITH_PYTHON:BOOL={0}".format(on_or_off("+python" in spec)),
        ]

        netcdf_str = {"none": "OFF", "serial": "Serial", "parallel": "Parallel"}

        args.append("-DWITH_NETCDF:STRING={0}".format(netcdf_str[spec.variants["netcdf"].value]))

        # Set an MPI compiler for parallel builds
        if "+mpi" in spec:
            args.append("-DCMAKE_CXX_COMPILER:PATH={0}".format(spec["mpi"].mpicxx))

        return args