import rpc_pb2 as ln
import rpc_pb2_grpc as lnrpc
import grpc
import os
import codecs

# Due to updated ECDSA generated tls.cert we need to let gprc know that
# we need to use that cipher suite otherwise there will be a handhsake
# error when we communicate with the lnd rpc server.
os.environ["GRPC_SSL_CIPHER_SUITES"] = 'HIGH+ECDSA'

cert = open(os.path.expanduser('~/.config/lightning-app/lnd/tls.cert'), 'rb').read()

with open(os.path.expanduser('~/.config/lightning-app/lnd/data/chain/bitcoin/mainnet/admin.macaroon'), 'rb') as f:
    macaroon_bytes = f.read()
    macaroon = codecs.encode(macaroon_bytes, 'hex')


def metadata_callback(context, callback):
    # for more info see grpc docs
    callback([('macaroon', macaroon)], None)


# build ssl credentials using the cert the same as before
cert_creds = grpc.ssl_channel_credentials(cert)

# now build meta data credentials
auth_creds = grpc.metadata_call_credentials(metadata_callback)

# combine the cert credentials and the macaroon auth credentials
# such that every call is properly encrypted and authenticated
combined_creds = grpc.composite_channel_credentials(cert_creds, auth_creds)

# finally pass in the combined credentials when creating a channel
channel = grpc.secure_channel('localhost:10006', combined_creds)
stub = lnrpc.LightningStub(channel)

# now every call will be made with the macaroon already included
print(stub.GetInfo(ln.GetInfoRequest()))