import pyldpc
import scipy.sparse
import numpy as np
import test_decoder
import os, sys
import ctypes as C
import argparse

if __name__ != '__main__':
    raise RuntimeError("Please don't import this module, this is a command-line program.")

parser = argparse.ArgumentParser()
parser.add_argument('-r', '--reference', action='store_true', default=False, help='Run reference decoder instead of C implemention')
args = parser.parse_args()

lib = C.CDLL('./ldpc_decoder_test.so')

n = 5*19
nodes, bits = 17, 19
H, G = pyldpc.make_ldpc(n, nodes, bits, systematic=False, seed=0)
_1, bits_pos, _2 = scipy.sparse.find(H)
_, k = G.shape

st = np.random.RandomState(seed=0)
test_data = st.randint(0, 2, k)
d = np.dot(G, test_data) % 2
x = (-1) ** d
x[29:] = 0

bits_pos = bits_pos.astype(np.uint32)
x = x.astype(np.int8)

lib.decode.argtypes = [C.c_size_t, C.c_size_t, C.c_size_t, C.POINTER(C.c_size_t), C.POINTER(C.c_int8), C.POINTER(C.c_int8), C.c_uint]
lib.get_message.argtypes = [C.c_size_t, C.c_size_t, C.POINTER(C.c_int8), C.POINTER(C.c_int8), C.POINTER(C.c_int8)]

if args.reference:
    ref_out = test_decoder.decode(H, x, 3)
    print('decoder output:', ref_out, flush=True)
    print('msg reconstruction:', test_decoder.get_message(G, ref_out))
    print('reference decoder: ', np.all(np.equal(test_decoder.get_message(G, ref_out), test_data)), flush=True)
    np.set_printoptions(linewidth=220)
    print(test_data)
    print(test_decoder.get_message(G, ref_out))
    print(test_decoder.get_message(G, ref_out) ^ test_data)

else:
    out = np.zeros(n, dtype=np.uint8)
    # print('python data:', x, flush=True)
    print('decoder iterations:', lib.decode(n, nodes, bits,
        bits_pos.ctypes.data_as(C.POINTER(C.c_ulong)),
        x.ctypes.data_as(C.POINTER(C.c_int8)),
        out.ctypes.data_as(C.POINTER(C.c_int8)),
        25), flush=True)
    print('decoder output:', out)
    print('msg reconstruction:', test_decoder.get_message(G, out.astype(np.int64)))
    print('decoder under test:', np.all(np.equal(test_decoder.get_message(G, out.astype(np.int64)), test_data)))
    np.set_printoptions(linewidth=220)
    print(test_data)
    print(test_decoder.get_message(G, out.astype(np.int64)))
    G = G.astype(np.int8)
    msg = np.zeros(k, dtype=np.int8)
    lib.get_message(
            n, k,
            G.ctypes.data_as(C.POINTER(C.c_int8)),
            out.astype(np.int8).ctypes.data_as(C.POINTER(C.c_int8)),
            msg.ctypes.data_as(C.POINTER(C.c_int8)))
    print(msg)
    print(msg ^ test_data)

print('codeword length:', len(x))
print('data length:', len(test_data))