import os
from collections import namedtuple

from cffi import FFI

here = os.path.dirname(os.path.abspath(__file__))

Source = namedtuple('Source', ('h', 'include'))


def _mk_ffi(sources, name='_libsecp256k1', **kwargs):
    _ffi = FFI()
    code = []

    for source in sources:
        with open(os.path.join(here, source.h), 'rt') as h:
            _ffi.cdef(h.read())
        code.append(source.include)

    code.append('#define PY_USE_BUNDLED')
    _ffi.set_source(name, '\n'.join(code), **kwargs)

    return _ffi


modules = [
    Source('secp256k1.h', '#include <secp256k1.h>'),
    Source('secp256k1_ecdh.h', '#include <secp256k1_ecdh.h>'),
    Source('secp256k1_recovery.h', '#include <secp256k1_recovery.h>'),
]

ffi = _mk_ffi(modules, libraries=['secp256k1'])