import base64
import json
import os
import unittest
import time
from typing import cast, Union, Dict
from unittest.mock import patch, Mock, AsyncMock

import http_ece
import py_vapid
import requests
from cryptography.hazmat.primitives.asymmetric import ec
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.backends import default_backend

from pywebpush import (
    WebPusher,
    NoData,
    WebPushException,
    CaseInsensitiveDict,
    webpush,
    webpush_async,
)


class WebpushTestUtils(unittest.TestCase):
    # This is a exported DER formatted string of an ECDH public key
    # This was lifted from the py_vapid tests.
    vapid_key = (
        "MHcCAQEEIPeN1iAipHbt8+/KZ2NIF8NeN24jqAmnMLFZEMocY8RboAoGCCqGSM49"
        "AwEHoUQDQgAEEJwJZq/GN8jJbo1GGpyU70hmP2hbWAUpQFKDByKB81yldJ9GTklB"
        "M5xqEwuPM7VuQcyiLDhvovthPIXx+gsQRQ=="
    )

    def _gen_subscription_info(self, recv_key=None, endpoint="https://example.com/"):
        if not recv_key:
            recv_key = ec.generate_private_key(ec.SECP256R1(), default_backend())
        return {
            "endpoint": endpoint,
            "keys": {
                "auth": base64.urlsafe_b64encode(os.urandom(16)).strip(b"="),
                "p256dh": self._get_pubkey_str(recv_key),
            },
        }

    def _get_pubkey_str(self, priv_key):
        return base64.urlsafe_b64encode(
            priv_key.public_key().public_bytes(
                encoding=serialization.Encoding.X962,
                format=serialization.PublicFormat.UncompressedPoint,
            )
        ).strip(b"=")

    def test_init(self):
        # use static values so we know what to look for in the reply
        subscription_info = {
            "endpoint": "https://example.com/",
            "keys": {
                "p256dh": (
                    "BOrnIslXrUow2VAzKCUAE4sIbK00daEZCswOcf8m3T"
                    "F8V82B-OpOg5JbmYLg44kRcvQC1E2gMJshsUYA-_zMPR8"
                ),
                "auth": "k8JV6sjdbhAi1n3_LDBLvA",
            },
        }
        rk_decode = (
            b'\x04\xea\xe7"\xc9W\xadJ0\xd9P3(%\x00\x13\x8b'
            b"\x08l\xad4u\xa1\x19\n\xcc\x0eq\xff&\xdd1"
            b"|W\xcd\x81\xf8\xeaN\x83\x92[\x99\x82\xe0\xe3"
            b"\x89\x11r\xf4\x02\xd4M\xa00\x9b!\xb1F\x00"
            b"\xfb\xfc\xcc=\x1f"
        )
        self.assertRaises(
            WebPushException, WebPusher, {"keys": {"p256dh": "AAA=", "auth": "AAA="}}
        )
        self.assertRaises(
            WebPushException,
            WebPusher,
            {"endpoint": "https://example.com", "keys": {"p256dh": "AAA="}},
        )
        self.assertRaises(
            WebPushException,
            WebPusher,
            {"endpoint": "https://example.com", "keys": {"auth": "AAA="}},
        )
        self.assertRaises(
            WebPushException,
            WebPusher,
            {
                "endpoint": "https://example.com",
                "keys": {"p256dh": "AAA=", "auth": "AAA="},
            },
        )

        push = WebPusher(subscription_info)
        assert push.subscription_info != subscription_info
        assert push.subscription_info["keys"] != subscription_info["keys"]
        assert push.subscription_info["endpoint"] == subscription_info["endpoint"]
        assert push.receiver_key == rk_decode
        assert push.auth_key == b'\x93\xc2U\xea\xc8\xddn\x10"\xd6}\xff,0K\xbc'

    def test_encode(self):
        for content_encoding in ["aesgcm", "aes128gcm"]:
            recv_key = ec.generate_private_key(ec.SECP256R1(), default_backend())
            subscription_info = self._gen_subscription_info(recv_key)
            data = "Mary had a little lamb, with some nice mint jelly"
            push = WebPusher(subscription_info)
            encoded = push.encode(data.encode(), content_encoding=content_encoding)
            """
            crypto_key = base64.urlsafe_b64encode(
                self._get_pubkey_str(recv_key)
            ).strip(b'=')
            """
            # Convert these b64 strings into their raw, binary form.
            raw_salt = None
            if "salt" in encoded:
                raw_salt = base64.urlsafe_b64decode(push._repad(encoded["salt"]))
            raw_dh = None
            if content_encoding != "aes128gcm":
                raw_dh = base64.urlsafe_b64decode(push._repad(encoded["crypto_key"]))
            raw_auth = base64.urlsafe_b64decode(
                push._repad(subscription_info["keys"]["auth"])
            )
            decoded = http_ece.decrypt(
                encoded["body"],
                salt=raw_salt,
                dh=raw_dh,
                private_key=recv_key,
                auth_secret=raw_auth,
                version=content_encoding,
            )
            assert decoded.decode("utf8") == data

    def test_bad_content_encoding(self):
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb, with some nice mint jelly"
        push = WebPusher(subscription_info)
        self.assertRaises(
            WebPushException, push.encode, data, content_encoding="aesgcm128"
        )

    @patch("requests.post")
    def test_send(self, mock_post):
        subscription_info = self._gen_subscription_info()
        headers = {"Crypto-Key": "pre-existing", "Authentication": "bearer vapid"}
        data = "Mary had a little lamb"
        WebPusher(subscription_info).send(data, headers)
        assert subscription_info.get("endpoint") == mock_post.call_args[0][0]
        pheaders = mock_post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"
        assert pheaders.get("AUTHENTICATION") == headers.get("Authentication")
        ckey = pheaders.get("crypto-key")
        assert "pre-existing" in ckey
        assert pheaders.get("content-encoding") == "aes128gcm"

    @patch("requests.post")
    def test_send_vapid(self, mock_post):
        mock_post.return_value.status_code = 200
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        webpush(
            subscription_info=subscription_info,
            data=data,
            vapid_private_key=self.vapid_key,
            vapid_claims={"sub": "mailto:ops@example.com"},
            content_encoding="aesgcm",
            headers={"Test-Header": "test-value"},
        )
        assert subscription_info.get("endpoint") == mock_post.call_args[0][0]
        pheaders = mock_post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"

        def repad(str):
            return str + "===="[: len(str) % 4]

        auth = json.loads(
            base64.urlsafe_b64decode(
                repad(pheaders["authorization"].split(".")[1])
            ).decode("utf8")
        )
        assert subscription_info.get("endpoint", "").startswith(auth["aud"])
        assert "vapid" in pheaders.get("authorization")
        ckey = pheaders.get("crypto-key")
        assert "dh=" in ckey
        assert pheaders.get("content-encoding") == "aesgcm"
        assert pheaders.get("test-header") == "test-value"

    @patch.object(WebPusher, "send")
    @patch.object(py_vapid.Vapid, "sign")
    def test_webpush_vapid_instance(self, vapid_sign, pusher_send):
        pusher_send.return_value.status_code = 200
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        vapid_key = py_vapid.Vapid.from_string(self.vapid_key)
        claims: Dict[str, Union[str, int]] = dict(
            sub="mailto:ops@example.com", aud="https://example.com"
        )
        webpush(
            subscription_info=subscription_info,
            data=data,
            vapid_private_key=vapid_key,
            vapid_claims=claims,
        )
        vapid_sign.assert_called_once_with(claims)
        pusher_send.assert_called_once()

    @patch.object(WebPusher, "send")
    @patch.object(py_vapid.Vapid, "sign")
    def test_webpush_vapid_exp(self, vapid_sign, pusher_send):
        pusher_send.return_value.status_code = 200
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        vapid_key = py_vapid.Vapid.from_string(self.vapid_key)
        claims = dict(
            sub="mailto:ops@example.com",
            aud="https://example.com",
            exp=int(time.time() - 48600),
        )
        webpush(
            subscription_info=subscription_info,
            data=data,
            vapid_private_key=vapid_key,
            vapid_claims=claims,
        )
        vapid_sign.assert_called_once_with(claims)
        pusher_send.assert_called_once()
        assert int(claims["exp"]) > int(time.time())

    @patch("requests.post")
    def test_send_bad_vapid_no_key(self, mock_post):
        mock_post.return_value.status_code = 200

        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        self.assertRaises(
            WebPushException,
            webpush,
            subscription_info=subscription_info,
            data=data,
            vapid_claims={
                "aud": "https://example.com",
                "sub": "mailto:ops@example.com",
            },
        )

    @patch("requests.post")
    def test_send_bad_vapid_bad_return(self, mock_post):
        mock_post.return_value.status_code = 410

        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        self.assertRaises(
            WebPushException,
            webpush,
            subscription_info=subscription_info,
            data=data,
            vapid_claims={
                "aud": "https://example.com",
                "sub": "mailto:ops@example.com",
            },
            vapid_private_key=self.vapid_key,
        )

    @patch("requests.post")
    def test_send_empty(self, mock_post):
        subscription_info = self._gen_subscription_info()
        headers = {"Crypto-Key": "pre-existing", "Authentication": "bearer vapid"}
        WebPusher(subscription_info).send("", headers)
        assert subscription_info.get("endpoint") == mock_post.call_args[0][0]
        pheaders = mock_post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"
        assert "encryption" not in pheaders
        assert pheaders.get("AUTHENTICATION") == headers.get("Authentication")
        ckey = pheaders.get("crypto-key")
        assert "pre-existing" in ckey

    def test_encode_empty(self):
        subscription_info = self._gen_subscription_info()
        headers = {"Crypto-Key": "pre-existing", "Authentication": "bearer vapid"}
        pusher = WebPusher(subscription_info)
        self.assertRaises(NoData, pusher.encode, "", headers)

    def test_encode_no_crypto(self):
        subscription_info = self._gen_subscription_info()
        del subscription_info["keys"]
        headers = {"Crypto-Key": "pre-existing", "Authentication": "bearer vapid"}
        data = "Something"
        pusher = WebPusher(subscription_info)
        self.assertRaises(WebPushException, pusher.encode, data, headers)

    @patch("requests.post")
    def test_send_no_headers(self, mock_post):
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        WebPusher(subscription_info).send(data)
        assert subscription_info.get("endpoint") == mock_post.call_args[0][0]
        pheaders = mock_post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"
        assert pheaders.get("content-encoding") == "aes128gcm"

    @patch("pywebpush.open")
    def test_as_curl(self, opener):
        subscription_info = self._gen_subscription_info()
        result = webpush(
            subscription_info,
            data="Mary had a little lamb",
            vapid_claims={
                "aud": "https://example.com",
                "sub": "mailto:ops@example.com",
            },
            vapid_private_key=self.vapid_key,
            curl=True,
        )
        result = cast(str, result)
        for s in [
            "curl -vX POST https://example.com",
            '-H "content-encoding: aes128gcm"',
            '-H "authorization: vapid ',
            '-H "ttl: 0"',
            '-H "content-length:',
        ]:
            assert s in result, f"missing: {s}"

    def test_ci_dict(self):
        ci = CaseInsensitiveDict({"Foo": "apple", "bar": "banana"})
        assert "apple" == ci["foo"]
        assert "apple" == ci.get("FOO")
        assert "apple" == ci.get("Foo")
        del ci["FOO"]
        assert ci.get("Foo") is None

    @patch("requests.post")
    def test_timeout(self, mock_post):
        mock_post.return_value.status_code = 200
        subscription_info = self._gen_subscription_info()
        WebPusher(subscription_info).send(timeout=5.2)
        assert mock_post.call_args[1].get("timeout") == 5.2
        webpush(subscription_info, timeout=10.001)
        assert mock_post.call_args[1].get("timeout") == 10.001

    @patch("requests.Session")
    def test_send_using_requests_session(self, mock_session):
        subscription_info = self._gen_subscription_info()
        headers = {"Crypto-Key": "pre-existing", "Authentication": "bearer vapid"}
        data = "Mary had a little lamb"
        WebPusher(subscription_info, requests_session=mock_session).send(data, headers)
        assert subscription_info.get("endpoint") == mock_session.post.call_args[0][0]
        pheaders = mock_session.post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"
        assert pheaders.get("AUTHENTICATION") == headers.get("Authentication")
        ckey = pheaders.get("crypto-key")
        assert "pre-existing" in ckey
        assert pheaders.get("content-encoding") == "aes128gcm"


class WebPusherAsyncTestCase(WebpushTestUtils, unittest.IsolatedAsyncioTestCase):
    @patch("aiohttp.ClientSession.post", new_callable=AsyncMock)
    async def test_send(self, mock_post):
        subscription_info = self._gen_subscription_info()
        headers = {"Crypto-Key": "pre-existing", "Authentication": "bearer vapid"}
        data = "Mary had a little lamb"
        await WebPusher(subscription_info).send_async(data, headers)
        assert subscription_info.get("endpoint") == mock_post.call_args[0][0]
        pheaders = mock_post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"
        assert pheaders.get("AUTHENTICATION") == headers.get("Authentication")
        ckey = pheaders.get("crypto-key")
        assert "pre-existing" in ckey
        assert pheaders.get("content-encoding") == "aes128gcm"

    @patch("aiohttp.ClientSession.post", new_callable=AsyncMock)
    async def test_send_empty(self, mock_post):
        subscription_info = self._gen_subscription_info()
        headers = {"Crypto-Key": "pre-existing", "Authentication": "bearer vapid"}
        await WebPusher(subscription_info).send_async("", headers)
        assert subscription_info.get("endpoint") == mock_post.call_args[0][0]
        pheaders = mock_post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"
        assert "encryption" not in pheaders
        assert pheaders.get("AUTHENTICATION") == headers.get("Authentication")
        ckey = pheaders.get("crypto-key")
        assert "pre-existing" in ckey

    @patch("aiohttp.ClientSession.post", new_callable=AsyncMock)
    async def test_send_no_headers(self, mock_post):
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        await WebPusher(subscription_info).send_async(data)
        assert subscription_info.get("endpoint") == mock_post.call_args[0][0]
        pheaders = mock_post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"
        assert pheaders.get("content-encoding") == "aes128gcm"

    @patch("aiohttp.ClientSession.post", new_callable=AsyncMock)
    async def test_timeout(self, mock_post):
        mock_post.return_value.status_code = 200
        subscription_info = self._gen_subscription_info()
        await WebPusher(subscription_info).send_async(timeout=5.2)
        assert mock_post.call_args[1].get("timeout") == 5.2

    @patch("aiohttp.ClientSession", new_callable=AsyncMock)
    async def test_send_using_requests_session(self, mock_session):
        subscription_info = self._gen_subscription_info()
        headers = {"Crypto-Key": "pre-existing", "Authentication": "bearer vapid"}
        data = "Mary had a little lamb"
        await WebPusher(subscription_info, aiohttp_session=mock_session).send_async(
            data, headers
        )
        assert subscription_info.get("endpoint") == mock_session.post.call_args[0][0]
        pheaders = mock_session.post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"
        assert pheaders.get("AUTHENTICATION") == headers.get("Authentication")
        ckey = pheaders.get("crypto-key")
        assert "pre-existing" in ckey
        assert pheaders.get("content-encoding") == "aes128gcm"

    @patch("aiohttp.ClientSession.post", new_callable=AsyncMock)
    async def test_webpush_async_vapid(self, mock_post):
        mock_post.return_value.status = 200
        mock_post.return_value.text = AsyncMock(return_value="")
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        await webpush_async(
            subscription_info=subscription_info,
            data=data,
            vapid_private_key=self.vapid_key,
            vapid_claims={"sub": "mailto:ops@example.com"},
            content_encoding="aesgcm",
            headers={"Test-Header": "test-value"},
        )
        assert subscription_info.get("endpoint") == mock_post.call_args[0][0]
        pheaders = mock_post.call_args[1].get("headers")
        assert pheaders.get("ttl") == "0"

        def repad(str):
            return str + "===="[: len(str) % 4]

        auth = json.loads(
            base64.urlsafe_b64decode(
                repad(pheaders["authorization"].split(".")[1])
            ).decode("utf8")
        )
        assert subscription_info.get("endpoint", "").startswith(auth["aud"])
        assert "vapid" in pheaders.get("authorization")
        ckey = pheaders.get("crypto-key")
        assert "dh=" in ckey
        assert pheaders.get("content-encoding") == "aesgcm"
        assert pheaders.get("test-header") == "test-value"

    @patch.object(WebPusher, "send_async")
    @patch.object(py_vapid.Vapid, "sign")
    async def test_webpush_async_vapid_instance(self, vapid_sign, pusher_send):
        mock_response = Mock()
        mock_response.status = 200
        pusher_send.return_value = mock_response
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        vapid_key = py_vapid.Vapid.from_string(self.vapid_key)
        claims: Dict[str, Union[str, int]] = dict(
            sub="mailto:ops@example.com", aud="https://example.com"
        )
        await webpush_async(
            subscription_info=subscription_info,
            data=data,
            vapid_private_key=vapid_key,
            vapid_claims=claims,
        )
        vapid_sign.assert_called_once_with(claims)
        pusher_send.assert_called_once()

    @patch.object(WebPusher, "send_async")
    @patch.object(py_vapid.Vapid, "sign")
    async def test_webpush_async_vapid_exp(self, vapid_sign, pusher_send):
        mock_response = Mock()
        mock_response.status = 200
        pusher_send.return_value = mock_response
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        vapid_key = py_vapid.Vapid.from_string(self.vapid_key)
        claims = dict(
            sub="mailto:ops@example.com",
            aud="https://example.com",
            exp=int(time.time() - 48600),
        )
        await webpush_async(
            subscription_info=subscription_info,
            data=data,
            vapid_private_key=vapid_key,
            vapid_claims=claims,
        )
        vapid_sign.assert_called_once_with(claims)
        pusher_send.assert_called_once()
        assert int(claims["exp"]) > int(time.time())

    async def test_webpush_async_bad_vapid_no_key(self):
        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        with self.assertRaises(WebPushException):
            await webpush_async(
                subscription_info=subscription_info,
                data=data,
                vapid_claims={
                    "aud": "https://example.com",
                    "sub": "mailto:ops@example.com",
                },
            )

    @patch("aiohttp.ClientSession.post", new_callable=AsyncMock)
    async def test_webpush_async_bad_vapid_bad_return(self, mock_post):
        mock_post.return_value.status = 410
        mock_post.return_value.reason = "Gone"
        mock_post.return_value.text = AsyncMock(return_value="Subscription expired")

        subscription_info = self._gen_subscription_info()
        data = "Mary had a little lamb"
        with self.assertRaises(WebPushException):
            await webpush_async(
                subscription_info=subscription_info,
                data=data,
                vapid_claims={
                    "aud": "https://example.com",
                    "sub": "mailto:ops@example.com",
                },
                vapid_private_key=self.vapid_key,
            )

    @patch("aiohttp.ClientSession.post", new_callable=AsyncMock)
    async def test_webpush_async_timeout(self, mock_post):
        mock_response = Mock()
        mock_response.status = 200
        mock_response.text = AsyncMock(return_value="")
        mock_post.return_value = mock_response
        subscription_info = self._gen_subscription_info()
        await webpush_async(subscription_info, timeout=10.001)
        assert mock_post.call_args[1].get("timeout") == 10.001

    async def test_webpush_async_as_curl(self):
        subscription_info = self._gen_subscription_info()
        result = await webpush_async(
            subscription_info,
            data="Mary had a little lamb",
            vapid_claims={
                "aud": "https://example.com",
                "sub": "mailto:ops@example.com",
            },
            vapid_private_key=self.vapid_key,
            curl=True,
        )
        result = cast(str, result)
        for s in [
            "curl -vX POST https://example.com",
            '-H "content-encoding: aes128gcm"',
            '-H "authorization: vapid ',
            '-H "ttl: 0"',
            '-H "content-length:',
        ]:
            assert s in result, f"missing: {s}"


class WebpushExceptionTestCase(unittest.TestCase):
    def test_exception(self):
        from requests import Response

        exp = WebPushException("foo")
        assert f"{exp}" == "WebPushException: foo"
        # Really should try to load the response to verify, but this mock
        # covers what we need.
        response = Mock(spec=Response)
        response.text = (
            '{"code": 401, "errno": 109, "error": '
            '"Unauthorized", "more_info": "http://'
            "autopush.readthedocs.io/en/latest/htt"
            'p.html#error-codes", "message": "Requ'
            "est did not validate missing authoriz"
            'ation header"}'
        )
        response.json.return_value = json.loads(response.text)
        response.status_code = 401
        response.reason = "Unauthorized"
        exp = WebPushException("foo", response)
        assert f"{exp}" == "WebPushException: foo, Response {}".format(
            response.text
        )
        assert f"{exp.response}", "<Response [401]>"
        assert cast(requests.Response, exp.response).json().get("errno") == 109
        exp = WebPushException("foo", [1, 2, 3])
        assert f"{exp}" == "WebPushException: foo, Response [1, 2, 3]"