"""Tests für die Highscore-API: Lesen, Einreichen, Validierung, Tokens, Rate-Limit."""

from __future__ import annotations

from collections.abc import Callable

import pytest
from flask import Flask
from flask.testing import FlaskClient

from app.models import get_db, insert_score


def _seed(app: Flask, entries: list[tuple[str, int]]) -> None:
    with app.app_context():
        db = get_db()
        for name, score in entries:
            insert_score(db, name, score, wave=1, duration_s=60)


# ------------------------------------------------------------------ GET /api/highscores


def test_highscores_empty(client: FlaskClient) -> None:
    response = client.get("/api/highscores")
    assert response.status_code == 200
    assert response.get_json() == {"highscores": []}
    assert response.headers["Cache-Control"] == "no-store"


def test_highscores_sorted_and_limited_to_top_10(app: Flask, client: FlaskClient) -> None:
    _seed(app, [(f"Spieler {i}", i * 100) for i in range(15)])
    scores = client.get("/api/highscores").get_json()["highscores"]
    assert len(scores) == 10
    assert [entry["score"] for entry in scores] == [1400 - i * 100 for i in range(10)]
    assert [entry["rank"] for entry in scores] == list(range(1, 11))
    assert set(scores[0]) == {"rank", "name", "score", "wave", "created_at"}


def test_highscore_ties_keep_older_entry_first(app: Flask, client: FlaskClient) -> None:
    _seed(app, [("Erster", 500), ("Zweiter", 500)])
    names = [entry["name"] for entry in client.get("/api/highscores").get_json()["highscores"]]
    assert names == ["Erster", "Zweiter"]


# ----------------------------------------------------------------- POST /api/runs


def test_start_run_returns_token(client: FlaskClient) -> None:
    response = client.post("/api/runs")
    assert response.status_code == 201
    token = response.get_json()["run_token"]
    assert isinstance(token, str) and len(token) > 20
    assert client.post("/api/runs").get_json()["run_token"] != token


# ----------------------------------------------------------- POST /api/highscores: Erfolg


def test_submit_valid_highscore(client: FlaskClient, valid_payload: Callable[..., dict]) -> None:
    response = client.post("/api/highscores", json=valid_payload())
    assert response.status_code == 201
    body = response.get_json()
    assert body["rank"] == 1
    assert body["name"] == "Kadettin Ada"
    assert body["highscores"][0]["score"] == 1234

    listed = client.get("/api/highscores").get_json()["highscores"]
    assert listed[0]["name"] == "Kadettin Ada"
    assert listed[0]["wave"] == 3


def test_submit_returns_rank_below_existing(
    app: Flask, client: FlaskClient, valid_payload: Callable[..., dict]
) -> None:
    _seed(app, [("Profi", 5000), ("Mittel", 1500), ("Anfänger", 100)])
    body = client.post("/api/highscores", json=valid_payload(score=1000)).get_json()
    assert body["rank"] == 3


def test_submit_sanitizes_name(client: FlaskClient, valid_payload: Callable[..., dict]) -> None:
    payload = valid_payload(name="  <b>Jürg</b>\u200b   Größli \x00 ")
    body = client.post("/api/highscores", json=payload).get_json()
    assert body["name"] == "bJürgb Größli"


# ------------------------------------------------------ POST /api/highscores: Validierung


@pytest.mark.parametrize(
    ("overrides", "field"),
    [
        ({"name": ""}, "name"),
        ({"name": "   "}, "name"),
        ({"name": "<>{}"}, "name"),
        ({"name": "A" * 17}, "name"),
        ({"name": "A" * 500}, "name"),
        ({"name": 42}, "name"),
        ({"name": None}, "name"),
        ({"score": -1}, "score"),
        ({"score": "1000"}, "score"),
        ({"score": 12.5}, "score"),
        ({"score": True}, "score"),
        ({"score": None}, "score"),
        ({"score": 10**12}, "score"),
        ({"wave": 0}, "wave"),
        ({"wave": "3"}, "wave"),
        ({"wave": 100_000}, "wave"),
        ({"duration_s": -5}, "duration_s"),
        ({"duration_s": 10**9}, "duration_s"),
        ({"run_token": ""}, "run_token"),
        ({"run_token": 123}, "run_token"),
        ({"run_token": "x" * 2000}, "run_token"),
    ],
)
def test_submit_rejects_invalid_fields(
    client: FlaskClient, valid_payload: Callable[..., dict], overrides: dict, field: str
) -> None:
    response = client.post("/api/highscores", json=valid_payload(**overrides))
    assert response.status_code == 400
    body = response.get_json()
    assert body["error"] == "validation_failed"
    assert field in body["fields"]


def test_submit_reports_all_invalid_fields_at_once(client: FlaskClient) -> None:
    response = client.post("/api/highscores", json={})
    assert response.status_code == 400
    assert set(response.get_json()["fields"]) == {
        "name",
        "score",
        "wave",
        "duration_s",
        "run_token",
    }


@pytest.mark.parametrize(
    "kwargs",
    [
        {"data": "kein json", "content_type": "application/json"},
        {"data": "name=Ada&score=5", "content_type": "application/x-www-form-urlencoded"},
        {"json": ["liste", "statt", "objekt"]},
        {"json": "nur ein string"},
    ],
)
def test_submit_rejects_non_object_bodies(client: FlaskClient, kwargs: dict) -> None:
    response = client.post("/api/highscores", **kwargs)
    assert response.status_code == 400
    assert response.get_json()["error"] == "invalid_json"


def test_submit_rejects_oversized_body(client: FlaskClient) -> None:
    response = client.post("/api/highscores", data="x" * 20_000, content_type="application/json")
    assert response.status_code == 413
    assert response.is_json


# ------------------------------------------------------ POST /api/highscores: Run-Token


def test_submit_rejects_forged_token(
    client: FlaskClient, valid_payload: Callable[..., dict]
) -> None:
    response = client.post("/api/highscores", json=valid_payload(run_token="gefälscht.token.xyz"))
    assert response.status_code == 422
    assert response.get_json()["error"] == "run_token_invalid"


def test_submit_rejects_token_signed_with_other_key(
    client: FlaskClient, valid_payload: Callable[..., dict], db_path
) -> None:
    from app import create_app

    other = create_app(
        {"TESTING": True, "SECRET_KEY": "anderer-key", "DATABASE_PATH": str(db_path)}
    ).test_client()
    foreign_token = other.post("/api/runs").get_json()["run_token"]
    response = client.post("/api/highscores", json=valid_payload(run_token=foreign_token))
    assert response.get_json()["error"] == "run_token_invalid"


def test_submit_rejects_expired_token(
    app: Flask,
    client: FlaskClient,
    issue_token: Callable[..., str],
    valid_payload: Callable[..., dict],
) -> None:
    token = issue_token(started_ago=app.config["RUN_TOKEN_MAX_AGE_SECONDS"] + 60)
    response = client.post("/api/highscores", json=valid_payload(run_token=token))
    assert response.status_code == 422
    assert response.get_json()["error"] == "run_token_expired"


def test_submit_rejects_reused_token(
    client: FlaskClient, issue_token: Callable[..., str], valid_payload: Callable[..., dict]
) -> None:
    token = issue_token(started_ago=200)
    assert client.post("/api/highscores", json=valid_payload(run_token=token)).status_code == 201
    response = client.post("/api/highscores", json=valid_payload(run_token=token))
    assert response.status_code == 409
    assert response.get_json()["error"] == "run_token_used"


# -------------------------------------------------- POST /api/highscores: Plausibilität


def test_submit_rejects_duration_longer_than_run(
    client: FlaskClient, issue_token: Callable[..., str], valid_payload: Callable[..., dict]
) -> None:
    token = issue_token(started_ago=60)
    response = client.post(
        "/api/highscores", json=valid_payload(run_token=token, duration_s=600, score=10)
    )
    assert response.status_code == 422
    assert response.get_json()["error"] == "implausible_score"


def test_submit_rejects_score_too_high_for_duration(
    client: FlaskClient, valid_payload: Callable[..., dict]
) -> None:
    response = client.post("/api/highscores", json=valid_payload(score=5_000_000, duration_s=60))
    assert response.status_code == 422
    assert response.get_json()["error"] == "implausible_score"


def test_submit_rejects_wave_unreachable_in_duration(
    client: FlaskClient, valid_payload: Callable[..., dict]
) -> None:
    response = client.post("/api/highscores", json=valid_payload(wave=80, duration_s=30, score=10))
    assert response.status_code == 422


def test_implausible_submission_does_not_burn_token(
    client: FlaskClient, issue_token: Callable[..., str], valid_payload: Callable[..., dict]
) -> None:
    token = issue_token(started_ago=120)
    bad = client.post("/api/highscores", json=valid_payload(run_token=token, score=9_999_999))
    assert bad.status_code == 422
    good = client.post("/api/highscores", json=valid_payload(run_token=token))
    assert good.status_code == 201


# ------------------------------------------------------------------------ Rate-Limit


def test_rate_limit_blocks_after_max_attempts(
    client: FlaskClient, valid_payload: Callable[..., dict]
) -> None:
    for _ in range(5):
        assert client.post("/api/highscores", json=valid_payload()).status_code == 201
    response = client.post("/api/highscores", json=valid_payload())
    assert response.status_code == 429
    body = response.get_json()
    assert body["error"] == "rate_limited"
    retry_after = int(response.headers["Retry-After"])
    assert 1 <= retry_after <= 600
    assert body["retry_after"] == retry_after


def test_rate_limit_counts_invalid_requests_too(client: FlaskClient) -> None:
    for _ in range(5):
        assert client.post("/api/highscores", json={}).status_code == 400
    assert client.post("/api/highscores", json={}).status_code == 429


def test_rate_limit_is_per_client(client: FlaskClient, valid_payload: Callable[..., dict]) -> None:
    for _ in range(5):
        client.post("/api/highscores", json={}, environ_base={"REMOTE_ADDR": "10.0.0.1"})
    blocked = client.post("/api/highscores", json={}, environ_base={"REMOTE_ADDR": "10.0.0.1"})
    assert blocked.status_code == 429
    other = client.post(
        "/api/highscores", json=valid_payload(), environ_base={"REMOTE_ADDR": "10.0.0.2"}
    )
    assert other.status_code == 201


def test_rate_limit_window_expires(
    app: Flask, client: FlaskClient, monkeypatch: pytest.MonkeyPatch
) -> None:
    import app.api as api_module

    fake_now = [1_000_000.0]
    monkeypatch.setattr(api_module, "_now", lambda: fake_now[0])
    for _ in range(5):
        client.post("/api/highscores", json={})
    assert client.post("/api/highscores", json={}).status_code == 429

    fake_now[0] += app.config["RATE_LIMIT_WINDOW_SECONDS"] + 1
    assert client.post("/api/highscores", json={}).status_code == 400


def test_rate_limit_does_not_store_plain_ip(app: Flask, client: FlaskClient) -> None:
    client.post("/api/highscores", json={}, environ_base={"REMOTE_ADDR": "203.0.113.7"})
    with app.app_context():
        hashes = [row[0] for row in get_db().execute("SELECT client_hash FROM submission_log")]
    assert hashes
    assert all("203.0.113.7" not in value for value in hashes)