"""Tests for api.telegram_auth.validate_init_data."""

import hashlib
import hmac
import json
from urllib.parse import quote, unquote


from api.telegram_auth import validate_init_data


def _make_init_data(
    user: dict | None,
    bot_token: str,
    auth_date: int | None = None,
) -> str:
    """Build initData string with valid HMAC for testing."""
    params = {}
    if user is not None:
        params["user"] = quote(json.dumps(user))
    if auth_date is not None:
        params["auth_date"] = str(auth_date)
    pairs = sorted(params.items())
    data_string = "\n".join(f"{k}={unquote(v)}" for k, v in pairs)
    secret_key = hmac.new(
        b"WebAppData",
        msg=bot_token.encode(),
        digestmod=hashlib.sha256,
    ).digest()
    computed = hmac.new(
        secret_key,
        msg=data_string.encode(),
        digestmod=hashlib.sha256,
    ).hexdigest()
    params["hash"] = computed
    return "&".join(f"{k}={v}" for k, v in sorted(params.items()))


def test_valid_payload_returns_username():
    bot_token = "123:ABC"
    user = {"id": 123, "username": "testuser", "first_name": "Test"}
    init_data = _make_init_data(user, bot_token)
    assert validate_init_data(init_data, bot_token) == "testuser"


def test_valid_payload_username_lowercase():
    bot_token = "123:ABC"
    user = {"id": 123, "username": "TestUser", "first_name": "Test"}
    init_data = _make_init_data(user, bot_token)
    assert validate_init_data(init_data, bot_token) == "testuser"


def test_invalid_hash_returns_none():
    bot_token = "123:ABC"
    user = {"id": 123, "username": "testuser"}
    init_data = _make_init_data(user, bot_token)
    # Tamper with hash
    init_data = init_data.replace("hash=", "hash=x")
    assert validate_init_data(init_data, bot_token) is None


def test_wrong_bot_token_returns_none():
    bot_token = "123:ABC"
    user = {"id": 123, "username": "testuser"}
    init_data = _make_init_data(user, bot_token)
    assert validate_init_data(init_data, "other:token") is None


def test_missing_user_returns_none():
    bot_token = "123:ABC"
    init_data = _make_init_data(None, bot_token)  # no user key
    assert validate_init_data(init_data, bot_token) is None


def test_user_without_username_returns_none():
    bot_token = "123:ABC"
    user = {"id": 123, "first_name": "Test"}  # no username
    init_data = _make_init_data(user, bot_token)
    assert validate_init_data(init_data, bot_token) is None


def test_empty_init_data_returns_none():
    assert validate_init_data("", "token") is None
    assert validate_init_data("   ", "token") is None


def test_empty_bot_token_returns_none():
    user = {"id": 1, "username": "u"}
    init_data = _make_init_data(user, "token")
    assert validate_init_data(init_data, "") is None


def test_auth_date_expiry_rejects_old_init_data():
    """When max_age_seconds is set, initData older than that is rejected."""
    import time as t

    bot_token = "123:ABC"
    user = {"id": 1, "username": "testuser"}
    # auth_date 100 seconds ago
    old_ts = int(t.time()) - 100
    init_data = _make_init_data(user, bot_token, auth_date=old_ts)
    assert validate_init_data(init_data, bot_token, max_age_seconds=60) is None
    assert validate_init_data(init_data, bot_token, max_age_seconds=200) == "testuser"


def test_auth_date_expiry_accepts_fresh_init_data():
    """Fresh auth_date within max_age_seconds is accepted."""
    import time as t

    bot_token = "123:ABC"
    user = {"id": 1, "username": "testuser"}
    fresh_ts = int(t.time()) - 10
    init_data = _make_init_data(user, bot_token, auth_date=fresh_ts)
    assert validate_init_data(init_data, bot_token, max_age_seconds=60) == "testuser"


def test_auth_date_expiry_requires_auth_date_when_max_age_set():
    """When max_age_seconds is set but auth_date is missing, return None."""
    bot_token = "123:ABC"
    user = {"id": 1, "username": "testuser"}
    init_data = _make_init_data(user, bot_token)  # no auth_date
    assert validate_init_data(init_data, bot_token, max_age_seconds=86400) is None
    assert validate_init_data(init_data, bot_token) == "testuser"