import json
from binascii import hexlify, unhexlify

from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.asymmetric import ec

from apps.cli.pisa_cli import build_appointment

from pisa import c_logger
from pisa.errors import *
from pisa.inspector import Inspector
from pisa.appointment import Appointment
from pisa.block_processor import BlockProcessor
from pisa.conf import MIN_DISPUTE_DELTA

from test.unit.conftest import get_random_value_hex

from common.constants import LOCATOR_LEN_BYTES, LOCATOR_LEN_HEX

c_logger.disabled = True

inspector = Inspector()
APPOINTMENT_OK = (0, None)

NO_HEX_STRINGS = [
    "R" * LOCATOR_LEN_HEX,
    get_random_value_hex(LOCATOR_LEN_BYTES - 1) + "PP",
    "$" * LOCATOR_LEN_HEX,
    " " * LOCATOR_LEN_HEX,
]
WRONG_TYPES = [
    [],
    "",
    get_random_value_hex(LOCATOR_LEN_BYTES),
    3.2,
    2.0,
    (),
    object,
    {},
    " " * LOCATOR_LEN_HEX,
    object(),
]
WRONG_TYPES_NO_STR = [[], unhexlify(get_random_value_hex(LOCATOR_LEN_BYTES)), 3.2, 2.0, (), object, {}, object()]


def sign_appointment(sk, appointment):
    data = json.dumps(appointment, sort_keys=True, separators=(",", ":")).encode("utf-8")
    return hexlify(sk.sign(data, ec.ECDSA(hashes.SHA256()))).decode("utf-8")


def test_check_locator():
    # Right appointment type, size and format
    locator = get_random_value_hex(LOCATOR_LEN_BYTES)
    assert Inspector.check_locator(locator) == APPOINTMENT_OK

    # Wrong size (too big)
    locator = get_random_value_hex(LOCATOR_LEN_BYTES + 1)
    assert Inspector.check_locator(locator)[0] == APPOINTMENT_WRONG_FIELD_SIZE

    # Wrong size (too small)
    locator = get_random_value_hex(LOCATOR_LEN_BYTES - 1)
    assert Inspector.check_locator(locator)[0] == APPOINTMENT_WRONG_FIELD_SIZE

    # Empty
    locator = None
    assert Inspector.check_locator(locator)[0] == APPOINTMENT_EMPTY_FIELD

    # Wrong type (several types tested, it should do for anything that is not a string)
    locators = [[], -1, 3.2, 0, 4, (), object, {}, object()]

    for locator in locators:
        assert Inspector.check_locator(locator)[0] == APPOINTMENT_WRONG_FIELD_TYPE

    # Wrong format (no hex)
    locators = NO_HEX_STRINGS
    for locator in locators:
        assert Inspector.check_locator(locator)[0] == APPOINTMENT_WRONG_FIELD_FORMAT


def test_check_start_time():
    # Time is defined in block height
    current_time = 100

    # Right format and right value (start time in the future)
    start_time = 101
    assert Inspector.check_start_time(start_time, current_time) == APPOINTMENT_OK

    # Start time too small (either same block or block in the past)
    start_times = [100, 99, 98, -1]
    for start_time in start_times:
        assert Inspector.check_start_time(start_time, current_time)[0] == APPOINTMENT_FIELD_TOO_SMALL

    # Empty field
    start_time = None
    assert Inspector.check_start_time(start_time, current_time)[0] == APPOINTMENT_EMPTY_FIELD

    # Wrong data type
    start_times = WRONG_TYPES
    for start_time in start_times:
        assert Inspector.check_start_time(start_time, current_time)[0] == APPOINTMENT_WRONG_FIELD_TYPE


def test_check_end_time():
    # Time is defined in block height
    current_time = 100
    start_time = 120

    # Right format and right value (start time before end and end in the future)
    end_time = 121
    assert Inspector.check_end_time(end_time, start_time, current_time) == APPOINTMENT_OK

    # End time too small (start time after end time)
    end_times = [120, 119, 118, -1]
    for end_time in end_times:
        assert Inspector.check_end_time(end_time, start_time, current_time)[0] == APPOINTMENT_FIELD_TOO_SMALL

    # End time too small (either same height as current block or in the past)
    current_time = 130
    end_times = [130, 129, 128, -1]
    for end_time in end_times:
        assert Inspector.check_end_time(end_time, start_time, current_time)[0] == APPOINTMENT_FIELD_TOO_SMALL

    # Empty field
    end_time = None
    assert Inspector.check_end_time(end_time, start_time, current_time)[0] == APPOINTMENT_EMPTY_FIELD

    # Wrong data type
    end_times = WRONG_TYPES
    for end_time in end_times:
        assert Inspector.check_end_time(end_time, start_time, current_time)[0] == APPOINTMENT_WRONG_FIELD_TYPE


def test_check_delta():
    # Right value, right format
    deltas = [MIN_DISPUTE_DELTA, MIN_DISPUTE_DELTA + 1, MIN_DISPUTE_DELTA + 1000]
    for delta in deltas:
        assert Inspector.check_delta(delta) == APPOINTMENT_OK

    # Delta too small
    deltas = [MIN_DISPUTE_DELTA - 1, MIN_DISPUTE_DELTA - 2, 0, -1, -1000]
    for delta in deltas:
        assert Inspector.check_delta(delta)[0] == APPOINTMENT_FIELD_TOO_SMALL

    # Empty field
    delta = None
    assert Inspector.check_delta(delta)[0] == APPOINTMENT_EMPTY_FIELD

    # Wrong data type
    deltas = WRONG_TYPES
    for delta in deltas:
        assert Inspector.check_delta(delta)[0] == APPOINTMENT_WRONG_FIELD_TYPE


def test_check_blob():
    # Right format and length
    encrypted_blob = get_random_value_hex(120)
    assert Inspector.check_blob(encrypted_blob) == APPOINTMENT_OK

    # # Wrong content
    # # FIXME: There is not proper defined format for this yet. It should be restricted by size at least, and check it
    # #        is multiple of the block size defined by the encryption function.

    # Wrong type
    encrypted_blobs = WRONG_TYPES_NO_STR
    for encrypted_blob in encrypted_blobs:
        assert Inspector.check_blob(encrypted_blob)[0] == APPOINTMENT_WRONG_FIELD_TYPE

    # Empty field
    encrypted_blob = None
    assert Inspector.check_blob(encrypted_blob)[0] == APPOINTMENT_EMPTY_FIELD

    # Wrong format (no hex)
    encrypted_blobs = NO_HEX_STRINGS
    for encrypted_blob in encrypted_blobs:
        assert Inspector.check_blob(encrypted_blob)[0] == APPOINTMENT_WRONG_FIELD_FORMAT


def test_check_appointment_signature(generate_keypair):
    client_sk, client_pk = generate_keypair

    dummy_appointment_request = {
        "tx": get_random_value_hex(192),
        "tx_id": get_random_value_hex(32),
        "start_time": 1500,
        "end_time": 50000,
        "dispute_delta": 200,
    }
    dummy_appointment = build_appointment(**dummy_appointment_request)

    # Verify that an appointment signed by the client is valid
    signature = sign_appointment(client_sk, dummy_appointment)
    assert Inspector.check_appointment_signature(dummy_appointment, signature, client_pk)

    fake_sk = ec.generate_private_key(ec.SECP256K1, default_backend())

    # Create a bad signature to make sure inspector rejects it
    bad_signature = sign_appointment(fake_sk, dummy_appointment)
    assert (
        Inspector.check_appointment_signature(dummy_appointment, bad_signature, client_pk)[0]
        == APPOINTMENT_INVALID_SIGNATURE
    )


def test_inspect(run_bitcoind, generate_keypair):
    # At this point every single check function has been already tested, let's test inspect with an invalid and a valid
    # appointments.

    client_sk, client_pk = generate_keypair

    # Invalid appointment, every field is empty
    appointment_data = dict()
    signature = sign_appointment(client_sk, appointment_data)
    appointment = inspector.inspect(appointment_data, signature, client_pk)
    assert type(appointment) == tuple and appointment[0] != 0

    # Valid appointment
    locator = get_random_value_hex(LOCATOR_LEN_BYTES)
    start_time = BlockProcessor.get_block_count() + 5
    end_time = start_time + 20
    dispute_delta = MIN_DISPUTE_DELTA
    encrypted_blob = get_random_value_hex(64)

    appointment_data = {
        "locator": locator,
        "start_time": start_time,
        "end_time": end_time,
        "dispute_delta": dispute_delta,
        "encrypted_blob": encrypted_blob,
    }

    signature = sign_appointment(client_sk, appointment_data)

    appointment = inspector.inspect(appointment_data, signature, client_pk)

    assert (
        type(appointment) == Appointment
        and appointment.locator == locator
        and appointment.start_time == start_time
        and appointment.end_time == end_time
        and appointment.dispute_delta == dispute_delta
        and appointment.encrypted_blob.data == encrypted_blob
    )