from datetime import datetime, timedelta, timezone

import pytest
from libervia.backend.core import exceptions

try:
    from libervia.backend.plugins.plugin_xep_0373 import XEP_0373, NS_OX
except exceptions.MissingModule as e:
    pytest.skip(f"Can't test XEP-0373: {e}", allow_module_level=True)
from libervia.backend.tools.xmpp_datetime import parse_datetime
from twisted.words.protocols.jabber import jid

a = jid.JID("foo@example.com")
b = jid.JID("bar@example.com")


def test_signcrypt_element_args() -> None:
    with pytest.raises(ValueError):
        XEP_0373.build_signcrypt_element([])


def test_signcrypt_element() -> None:
    signcrypt_elt, payload_elt = XEP_0373.build_signcrypt_element([a, b])
    payload_elt.addElement("signcrypt-test-content", content="signcrypt test content")

    rpad_elt = next(signcrypt_elt.elements(NS_OX, "rpad"))
    time_elt = next(signcrypt_elt.elements(NS_OX, "time"))

    rpad = str(rpad_elt)
    timestamp = parse_datetime(time_elt["stamp"])

    signcrypt_elt.children.remove(rpad_elt)
    signcrypt_elt.children.remove(time_elt)

    # Our implementation uses a minimum of 50 characters for security
    assert len(rpad) >= 50
    assert (datetime.now(timezone.utc) - timestamp) < timedelta(seconds=10)
    assert signcrypt_elt.toXml() == (
        "<signcrypt xmlns='urn:xmpp:openpgp:0'>"
        "<to jid='foo@example.com'/>"
        "<to jid='bar@example.com'/>"
        "<payload>"
        "<signcrypt-test-content>signcrypt test content</signcrypt-test-content>"
        "</payload>"
        "</signcrypt>"
    )


def test_sign_element_args() -> None:
    with pytest.raises(ValueError):
        XEP_0373.build_sign_element([], True)


def test_sign_element_with_rpad() -> None:
    sign_elt, payload_elt = XEP_0373.build_sign_element([a, b], True)
    payload_elt.addElement("sign-test-content", content="sign test content")

    rpad_elt = next(sign_elt.elements(NS_OX, "rpad"))
    time_elt = next(sign_elt.elements(NS_OX, "time"))

    rpad = str(rpad_elt)
    timestamp = parse_datetime(time_elt["stamp"])

    sign_elt.children.remove(rpad_elt)
    sign_elt.children.remove(time_elt)

    # Our implementation uses a minimum of 50 characters for security
    assert len(rpad) >= 50
    assert (datetime.now(timezone.utc) - timestamp) < timedelta(seconds=10)
    assert sign_elt.toXml() == (
        "<sign xmlns='urn:xmpp:openpgp:0'>"
        "<to jid='foo@example.com'/>"
        "<to jid='bar@example.com'/>"
        "<payload>"
        "<sign-test-content>sign test content</sign-test-content>"
        "</payload>"
        "</sign>"
    )


def test_sign_element_without_rpad() -> None:
    sign_elt, payload_elt = XEP_0373.build_sign_element([a, b], False)
    payload_elt.addElement("sign-test-content", content="sign test content")

    rpad_elt = next(sign_elt.elements(NS_OX, "rpad"), None)
    time_elt = next(sign_elt.elements(NS_OX, "time"))

    timestamp = parse_datetime(time_elt["stamp"])

    sign_elt.children.remove(time_elt)

    assert rpad_elt is None
    assert (datetime.now(timezone.utc) - timestamp) < timedelta(seconds=10)
    assert sign_elt.toXml() == (
        "<sign xmlns='urn:xmpp:openpgp:0'>"
        "<to jid='foo@example.com'/>"
        "<to jid='bar@example.com'/>"
        "<payload>"
        "<sign-test-content>sign test content</sign-test-content>"
        "</payload>"
        "</sign>"
    )


def test_crypt_element_with_recipients() -> None:
    crypt_elt, payload_elt = XEP_0373.build_crypt_element([a, b])
    payload_elt.addElement("crypt-test-content", content="crypt test content")

    rpad_elt = next(crypt_elt.elements(NS_OX, "rpad"))
    time_elt = next(crypt_elt.elements(NS_OX, "time"))

    rpad = str(rpad_elt)
    timestamp = parse_datetime(time_elt["stamp"])

    crypt_elt.children.remove(rpad_elt)
    crypt_elt.children.remove(time_elt)

    # Our implementation uses a minimum of 50 characters for security
    assert len(rpad) >= 50
    assert (datetime.now(timezone.utc) - timestamp) < timedelta(seconds=10)
    assert crypt_elt.toXml() == (
        "<crypt xmlns='urn:xmpp:openpgp:0'>"
        "<to jid='foo@example.com'/>"
        "<to jid='bar@example.com'/>"
        "<payload>"
        "<crypt-test-content>crypt test content</crypt-test-content>"
        "</payload>"
        "</crypt>"
    )


def test_crypt_element_without_recipients() -> None:
    crypt_elt, payload_elt = XEP_0373.build_crypt_element([])
    payload_elt.addElement("crypt-test-content", content="crypt test content")

    rpad_elt = next(crypt_elt.elements(NS_OX, "rpad"))
    time_elt = next(crypt_elt.elements(NS_OX, "time"))

    rpad = str(rpad_elt)
    timestamp = parse_datetime(time_elt["stamp"])

    crypt_elt.children.remove(rpad_elt)
    crypt_elt.children.remove(time_elt)

    # Our implementation uses a minimum of 50 characters for security
    assert len(rpad) >= 50
    assert (datetime.now(timezone.utc) - timestamp) < timedelta(seconds=10)
    assert crypt_elt.toXml() == (
        "<crypt xmlns='urn:xmpp:openpgp:0'>"
        "<payload>"
        "<crypt-test-content>crypt test content</crypt-test-content>"
        "</payload>"
        "</crypt>"
    )
