import numpy as np
import pyopencl as cl
import loopy as lp
import sys

from pyopencl.tools import (  # noqa
        pytest_generate_tests_for_pyopencl
        as pytest_generate_tests)


_WENO_PRG = []


def get_weno_program():
    if _WENO_PRG:
        return _WENO_PRG[0]

    fn = "WENO.F90"

    with open(fn, "r") as infile:
        infile_content = infile.read()

    prg = lp.parse_transformed_fortran(infile_content, filename=fn)
    _WENO_PRG.append(prg)
    return prg


def with_root_kernel(prg, name):
    # FIXME This is a little less beautiful than it could be
    new_prg = prg.copy(name=name)
    for name in prg:
        clbl = new_prg[name]
        if isinstance(clbl, lp.LoopKernel) and clbl.is_called_from_host:
            new_prg = new_prg.with_kernel(clbl.copy(is_called_from_host=False))

    new_prg = new_prg.with_kernel(prg[name].copy(is_called_from_host=True))
    return new_prg


def test_matvec(ctx_factory):
    ctx = ctx_factory()
    queue = cl.CommandQueue(ctx)

    prg = get_weno_program()
    prg = with_root_kernel(prg, "mult_mat_vec")
    print(prg)

    a = np.random.randn(10, 10)
    b = np.random.randn(10)
    c = np.zeros(10)

    prg(queue, a=a, b=b, c=c, alpha=1.0)


# This lets you run 'python test.py test_case(cl._csc)' without pytest.

if __name__ == "__main__":
    if len(sys.argv) > 1:
        exec(sys.argv[1])
    else:
        from pytest import main
        main([__file__])