"""Integration regression for NK-WP-0041; needs requests, PyYAML, cryptography."""

import argparse
import base64
import json
import pathlib
import socket
import subprocess
import tempfile
import time
import urllib.parse

import requests
import yaml
from cryptography.hazmat.primitives import hashes, serialization
from cryptography.hazmat.primitives.asymmetric import padding, rsa


def decode(value):
    return base64.urlsafe_b64decode(value + "=" * (-len(value) % 4))

parser = argparse.ArgumentParser(
    description="Exercise real Authelia ID tokens with and without the KeyCape claims policy; scratch data only."
)
parser.add_argument("--authelia-bin", required=True)
binary = str(pathlib.Path(parser.parse_args().authelia_bin).resolve())
key = rsa.generate_private_key(public_exponent=65537, key_size=2048)
pem = key.private_bytes(
    serialization.Encoding.PEM,
    serialization.PrivateFormat.PKCS8,
    serialization.NoEncryption(),
).decode()
source = yaml.safe_load(
    yaml.safe_load(
        (pathlib.Path(__file__).resolve().parents[1] / "configmap.yaml").read_text()
    )["data"]["configuration.yml"]
)["identity_providers"]["oidc"]
for enabled in (False, True):
    with tempfile.TemporaryDirectory(prefix="nk-claims-") as tmp:
        p = pathlib.Path(tmp)
        with socket.socket() as s:
            s.bind(("127.0.0.1", 0))
            port = s.getsockname()[1]
        password = "scratch-password-only"
        digest = (
            subprocess.check_output(
                [
                    binary,
                    "crypto",
                    "hash",
                    "generate",
                    "argon2",
                    "--password",
                    password,
                ],
                text=True,
            )
            .strip()
            .split("Digest: ")[1]
        )
        (p / "users.yml").write_text(
            yaml.safe_dump(
                {
                    "users": {
                        "nk-probe": {
                            "displayname": "Scratch User",
                            "password": digest,
                            "email": "nk-probe+x@example.com",
                            "groups": [],
                        }
                    }
                }
            )
        )
        client = dict(source["clients"][0])
        client.update(
            secret="scratch-client-secret-only",
            redirect_uris=["https://client.example.com/callback"],
        )
        if not enabled:
            client.pop("claims_policy")
        oidc = {
            "hmac_secret": "h" * 64,
            "jwks": [{"key": pem, "algorithm": "RS256", "use": "sig"}],
            "clients": [client],
        }
        if enabled:
            oidc["claims_policies"] = source["claims_policies"]
        cfg = {
            "ntp": {"disable_startup_check": True},
            "server": {"address": f"tcp://127.0.0.1:{port}/"},
            "log": {"level": "info"},
            "authentication_backend": {"file": {"path": str(p / "users.yml")}},
            "session": {
                "secret": "s" * 64,
                "cookies": [
                    {
                        "domain": "example.com",
                        "authelia_url": "https://auth.example.com",
                    }
                ],
            },
            "storage": {
                "encryption_key": "e" * 64,
                "local": {"path": str(p / "db.sqlite3")},
            },
            "notifier": {"filesystem": {"filename": str(p / "notifications")}},
            "access_control": {"default_policy": "one_factor"},
            "identity_validation": {"reset_password": {"jwt_secret": "j" * 64}},
            "identity_providers": {"oidc": oidc},
        }
        (p / "config.yml").write_text(yaml.safe_dump(cfg))
        with (p / "log").open("w") as log:
            proc = subprocess.Popen(
                [binary, "--config", str(p / "config.yml")], stdout=log, stderr=log
            )
            try:
                session = requests.Session()
                session.trust_env = False
                base = f"http://127.0.0.1:{port}"
                session.headers.update(
                    {
                        "Host": "auth.example.com",
                        "X-Forwarded-Proto": "https",
                        "X-Forwarded-Host": "auth.example.com",
                    }
                )
                for _ in range(100):
                    if proc.poll() is not None:
                        raise RuntimeError((p / "log").read_text())
                    try:
                        if (
                            session.get(base + "/api/health", timeout=1).status_code
                            == 200
                        ):
                            break
                    except requests.ConnectionError:
                        pass
                    time.sleep(0.1)
                else:
                    raise RuntimeError("Scratch Authelia did not become healthy")
                r = session.post(
                    base + "/api/firstfactor",
                    json={
                        "username": "nk-probe",
                        "password": password,
                        "keepMeLoggedIn": False,
                    },
                    timeout=5,
                )
                assert r.status_code == 200, (r.status_code, r.text)
                session.headers["Cookie"] = "; ".join(
                    c.name + "=" + c.value for c in session.cookies
                )
                r = session.get(
                    base + "/api/oidc/authorization",
                    params={
                        "client_id": "keycape",
                        "redirect_uri": "https://client.example.com/callback",
                        "response_type": "code",
                        "scope": "openid profile email groups",
                        "state": "scratch-state-long-enough",
                        "nonce": "scratch-nonce-long-enough",
                    },
                    allow_redirects=False,
                    timeout=5,
                )
                loc = r.headers.get("Location", "")
                query = urllib.parse.parse_qs(urllib.parse.urlparse(loc).query)
                assert "code" in query, (
                    r.status_code,
                    loc,
                    r.text,
                    (p / "log").read_text(),
                )
                r = session.post(
                    base + "/api/oidc/token",
                    auth=("keycape", "scratch-client-secret-only"),
                    data={
                        "grant_type": "authorization_code",
                        "code": query["code"][0],
                        "redirect_uri": "https://client.example.com/callback",
                    },
                    timeout=5,
                )
                assert r.status_code == 200, (r.status_code, r.text)
                parts = r.json()["id_token"].split(".")
                key.public_key().verify(
                    decode(parts[2]),
                    (".".join(parts[:2])).encode(),
                    padding.PKCS1v15(),
                    hashes.SHA256(),
                )
                claims = json.loads(decode(parts[1]))
                assert claims["iss"] == "https://auth.example.com"
                assert "keycape" in claims["aud"]
                assert claims["nonce"] == "scratch-nonce-long-enough"
                assert claims["exp"] > time.time()
                assert (claims.get("preferred_username") == "nk-probe") == enabled
                assert claims["sub"] != "nk-probe"
                print(
                    json.dumps(
                        {
                            "claims_policy": enabled,
                            "signed_id_token_verified": True,
                            "preferred_username_present": "preferred_username"
                            in claims,
                            "subject_is_directory_username": False,
                        }
                    )
                )
            finally:
                proc.terminate()
                proc.wait(timeout=10)