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from virgil_crypto_lib._libs import *
from ctypes import *
from virgil_crypto_lib.common._c_bridge import vsc_buffer_t
from virgil_crypto_lib.common._c_bridge import vsc_data_t
from ._vscf_impl import vscf_impl_t


class vscf_key_material_rng_t(Structure):
    pass


class VscfKeyMaterialRng(object):
    """Random number generator that generate deterministic sequence based
    on a given seed.
    This RNG can be used to transform key material rial to the private key."""

    # Minimum length in bytes for the key material.
    KEY_MATERIAL_LEN_MIN = 32
    # Maximum length in bytes for the key material.
    KEY_MATERIAL_LEN_MAX = 512

    def __init__(self):
        """Create underlying C context."""
        self._ll = LowLevelLibs()
        self._lib = self._ll.foundation

    def vscf_key_material_rng_new(self):
        vscf_key_material_rng_new = self._lib.vscf_key_material_rng_new
        vscf_key_material_rng_new.argtypes = []
        vscf_key_material_rng_new.restype = POINTER(vscf_key_material_rng_t)
        return vscf_key_material_rng_new()

    def vscf_key_material_rng_delete(self, ctx):
        vscf_key_material_rng_delete = self._lib.vscf_key_material_rng_delete
        vscf_key_material_rng_delete.argtypes = [POINTER(vscf_key_material_rng_t)]
        vscf_key_material_rng_delete.restype = None
        return vscf_key_material_rng_delete(ctx)

    def vscf_key_material_rng_random(self, ctx, data_len, data):
        """Generate random bytes.
        All RNG implementations must be thread-safe."""
        vscf_key_material_rng_random = self._lib.vscf_key_material_rng_random
        vscf_key_material_rng_random.argtypes = [POINTER(vscf_key_material_rng_t), c_size_t, POINTER(vsc_buffer_t)]
        vscf_key_material_rng_random.restype = c_int
        return vscf_key_material_rng_random(ctx, data_len, data)

    def vscf_key_material_rng_reseed(self, ctx):
        """Retrieve new seed data from the entropy sources."""
        vscf_key_material_rng_reseed = self._lib.vscf_key_material_rng_reseed
        vscf_key_material_rng_reseed.argtypes = [POINTER(vscf_key_material_rng_t)]
        vscf_key_material_rng_reseed.restype = c_int
        return vscf_key_material_rng_reseed(ctx)

    def vscf_key_material_rng_reset_key_material(self, ctx, key_material):
        """Set a new key material."""
        vscf_key_material_rng_reset_key_material = self._lib.vscf_key_material_rng_reset_key_material
        vscf_key_material_rng_reset_key_material.argtypes = [POINTER(vscf_key_material_rng_t), vsc_data_t]
        vscf_key_material_rng_reset_key_material.restype = None
        return vscf_key_material_rng_reset_key_material(ctx, key_material)

    def vscf_key_material_rng_shallow_copy(self, ctx):
        vscf_key_material_rng_shallow_copy = self._lib.vscf_key_material_rng_shallow_copy
        vscf_key_material_rng_shallow_copy.argtypes = [POINTER(vscf_key_material_rng_t)]
        vscf_key_material_rng_shallow_copy.restype = POINTER(vscf_key_material_rng_t)
        return vscf_key_material_rng_shallow_copy(ctx)

    def vscf_key_material_rng_impl(self, ctx):
        vscf_key_material_rng_impl = self._lib.vscf_key_material_rng_impl
        vscf_key_material_rng_impl.argtypes = [POINTER(vscf_key_material_rng_t)]
        vscf_key_material_rng_impl.restype = POINTER(vscf_impl_t)
        return vscf_key_material_rng_impl(ctx)
