# Copyright (C) 2015-2020 Virgil Security, Inc.
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#     (2) Redistributions in binary form must reproduce the above copyright
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#     contributors may be used to endorse or promote products derived from
#     this software without specific prior written permission.
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# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ''AS IS'' AND ANY EXPRESS OR
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# Lead Maintainer: Virgil Security Inc. <support@virgilsecurity.com>


from virgil_crypto_lib._libs import *
from ._vsc_data import vsc_data_t
from ctypes import *


class vsc_buffer_t(Structure):
    pass


class VscBuffer(object):
    """Encapsulates fixed byte array with variable effective data length."""

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

    def vsc_buffer_new(self):
        # vsc_buffer_new C function wrapper
        vsc_buffer_new = self._lib.vsc_buffer_new
        vsc_buffer_new.restype = POINTER(vsc_buffer_t)
        return vsc_buffer_new()

    def vsc_buffer_new_with_data(self, data):
        # vsc_buffer_new_with_data C function wrapper
        vsc_buffer_new_with_data = self._lib.vsc_buffer_new_with_data
        vsc_buffer_new_with_data.argtypes = [vsc_data_t]
        vsc_buffer_new_with_data.restype = POINTER(vsc_buffer_t)
        return vsc_buffer_new_with_data(data)

    def vsc_buffer_destroy(self, buffer):
        # vsc_buffer_destroy C function wrapper
        vsc_buffer_destroy = self._lib.vsc_buffer_destroy
        vsc_buffer_destroy.argtypes = [POINTER(POINTER(vsc_buffer_t))]
        return vsc_buffer_destroy(buffer)

    def vsc_buffer_equal(self, buffer, rhs):
        vsc_buffer_equal = self._lib.vsc_buffer_equal
        vsc_buffer_equal.argtypes = [POINTER(vsc_buffer_t), POINTER(vsc_buffer_t)]
        vsc_buffer_equal.restype = c_bool
        return vsc_buffer_equal(buffer, rhs)

    def vsc_buffer_use(self, buffer, bytes_, bytes_len):
        # vsc_buffer_use C function wrapper
        vsc_buffer_use = self._lib.vsc_buffer_use
        vsc_buffer_use.argtypes = [
            POINTER(vsc_buffer_t),
            POINTER(c_byte),
            c_size_t
        ]
        return vsc_buffer_use(buffer, bytes_, bytes_len)

    def vsc_buffer_len(self, buffer):
        vsc_buffer_len = self._lib.vsc_buffer_len
        vsc_buffer_len.argtypes = [POINTER(vsc_buffer_t)]
        vsc_buffer_len.restype = c_size_t
        return vsc_buffer_len(buffer)

    def vsc_buffer_shallow_copy(self, buffer):
        vsc_buffer_shallow_copy = self._lib.vsc_buffer_shallow_copy
        vsc_buffer_shallow_copy.argtypes = [POINTER(vsc_buffer_t)]
        vsc_buffer_shallow_copy.restype = POINTER(vsc_buffer_t)
        return vsc_buffer_shallow_copy(buffer)
