"""Рейтинг в витринах (#23): Elo по упорядоченной истории, общая и групповая цепочки."""
from __future__ import annotations

from fastapi.testclient import TestClient

from app.services.scoring import RatedMatch, RatedSeat, replay
from tests.conftest import add_group_member, create_finished_match, csrf_headers, login


def _group(client: TestClient, name: str = "Группа") -> tuple[int, list[int]]:
    gid = client.post(
        "/api/groups", json={"name": name, "expansion_ids": []}, headers=csrf_headers(client)
    ).json()["id"]
    fids = [f["id"] for f in client.get(f"/api/groups/{gid}/factions").json()]
    return gid, fids


def _duel(client: TestClient, gid: int, fids: list[int], winner: int, loser: int) -> dict:
    return create_finished_match(
        client, gid,
        [
            {"user_id": winner, "faction_id": fids[0], "place": 1},
            {"user_id": loser, "faction_id": fids[1], "place": 2},
        ],
    )


def _board(client: TestClient, path: str = "/api/stats/leaderboard") -> dict[int, dict]:
    data = client.get(path).json()
    rows = data["entries"] + data["provisional"] if "entries" in data else (
        data["leaderboard"] + data["provisional"]
    )
    return {e["user_id"]: e for e in rows}


def test_newcomer_duel_moves_rating_by_32(client: TestClient, engine):
    """Первая дуэль новичков на 1500: K = 64, ожидание 0.5, деталей нет → ±32."""
    me = login(client, "Хозяин")
    gid, fids = _group(client)
    b = add_group_member(engine, gid, "Гость")
    _duel(client, gid, fids, me["id"], b)

    board = client.get("/api/stats/leaderboard").json()
    by_id = {e["user_id"]: e for e in board["entries"] + board["provisional"]}
    assert by_id[me["id"]]["score"] == 1532
    assert by_id[b]["score"] == 1468
    # 1 игра < MIN_GAMES=10 → оба пока «Новички», ранжированный топ пуст.
    assert board["entries"] == []
    assert board["min_games"] == 10

    prof = client.get("/api/users/me/stats").json()
    assert prof["overall"]["score"] == 1532
    # Фракционная метрика — S − E: победа при шансах 0.5 даёт +0.5 → 50.0.
    assert prof["factions"][0]["score"] == 50.0


def test_ranked_after_min_games(client: TestClient, engine):
    me = login(client, "Чемпион")
    gid, fids = _group(client)
    b = add_group_member(engine, gid, "Спарринг")
    for _ in range(10):
        _duel(client, gid, fids, me["id"], b)
    board = client.get("/api/stats/leaderboard").json()
    ranks = {e["user_id"]: (e["rank"], e["score"]) for e in board["entries"]}
    assert ranks[me["id"]][0] == 1 and ranks[b][0] == 2
    assert ranks[me["id"]][1] > 1500 > ranks[b][1]
    assert isinstance(ranks[me["id"]][1], int)


def test_editing_past_match_recalculates_later_ones(client: TestClient, engine):
    """Рейтинг — функция истории: правка первой партии меняет итог после второй."""
    me = login(client, "А")
    gid, fids = _group(client)
    b = add_group_member(engine, gid, "Б")
    first = _duel(client, gid, fids, me["id"], b)
    _duel(client, gid, fids, me["id"], b)

    def expected(first_winner: int, first_loser: int) -> dict[int, int]:
        rep = replay([
            RatedMatch((RatedSeat(first_winner, 1), RatedSeat(first_loser, 2)), "objectives", id=1),
            RatedMatch((RatedSeat(me["id"], 1), RatedSeat(b, 2)), "objectives", id=2),
        ])
        return {uid: round(r) for uid, r in rep.ratings.items()}

    before = expected(me["id"], b)
    assert {uid: e["score"] for uid, e in _board(client).items()} == before

    rows = [
        {"user_id": b, "faction_id": fids[1], "place": 1},
        {"user_id": me["id"], "faction_id": fids[0], "place": 2},
    ]
    r = client.patch(
        f"/api/matches/{first['id']}",
        json={"participants": rows, "win_reason": "objectives"},
        headers=csrf_headers(client),
    )
    assert r.status_code == 200, r.text
    after = expected(b, me["id"])
    assert after != before
    assert {uid: e["score"] for uid, e in _board(client).items()} == after


def test_group_rating_is_its_own_chain(client: TestClient, engine):
    """Групповой рейтинг проигрывает только партии группы, общий — все партии."""
    me = login(client, "Путешественник")
    g1, f1 = _group(client, "Первая")
    g2, f2 = _group(client, "Вторая")
    b = add_group_member(engine, g1, "Сосед")
    c = add_group_member(engine, g2, "Соседка")
    _duel(client, g1, f1, me["id"], b)  # в первой группе — победа
    _duel(client, g2, f2, c, me["id"])  # во второй — поражение

    assert _board(client, f"/api/groups/{g1}/stats")[me["id"]]["score"] == 1532
    assert _board(client, f"/api/groups/{g2}/stats")[me["id"]]["score"] == 1468
    overall = _board(client)[me["id"]]["score"]
    assert overall not in (1532, 1468)
    assert overall == round(
        replay([
            RatedMatch((RatedSeat(me["id"], 1), RatedSeat(b, 2)), "objectives", id=1),
            RatedMatch((RatedSeat(c, 1), RatedSeat(me["id"], 2)), "objectives", id=2),
        ]).ratings[me["id"]]
    )


def test_best_match_is_biggest_rating_gain(client: TestClient, engine):
    """Лучшая партия — наибольший прирост рейтинга, а не свежая из равных побед.

    Обе партии — победы в дуэли. Первая — новичком над равным (+32), вторая — уже
    с рейтингом 1532 и меньшим K над новичком (≈ +28): лучше первая."""
    me = login(client, "Лучший")
    gid, fids = _group(client)
    x = add_group_member(engine, gid, "Икс")
    y = add_group_member(engine, gid, "Игрек")
    first = _duel(client, gid, fids, me["id"], x)
    _duel(client, gid, fids, me["id"], y)

    client.patch("/api/users/me/profile", json={"history_mode": "best"}, headers=csrf_headers(client))
    data = client.get(f"/api/users/{me['id']}/matches").json()
    assert data["total"] == 1
    assert data["items"][0]["id"] == first["id"]


def test_history_shows_rating_delta_of_its_owner(client: TestClient, engine):
    """История игрока несёт изменение его общего рейтинга за каждую партию (#77)."""
    me = login(client, "Историк")
    gid, fids = _group(client)
    b = add_group_member(engine, gid, "Оппонент")
    _duel(client, gid, fids, me["id"], b)  # новички на 1500: ±32
    _duel(client, gid, fids, b, me["id"])  # реванш: 1468 обыгрывает 1532

    mine = client.get(f"/api/users/{me['id']}/matches").json()["items"]
    theirs = client.get(f"/api/users/{b}/matches").json()["items"]
    # Свежие сверху: реванш первым.
    assert (mine[1]["rating_delta"], theirs[1]["rating_delta"]) == (32.0, -32.0)
    assert mine[0]["rating_delta"] == -theirs[0]["rating_delta"] < 0
    # Изменения складываются в рейтинг (с точностью округления до десятых).
    score = _board(client)[me["id"]]["score"]
    assert abs(1500 + sum(i["rating_delta"] for i in mine) - score) <= 0.6

    # В списке партий группы дельты нет — непонятно, чья она была бы.
    group_items = client.get(f"/api/groups/{gid}/matches").json()["items"]
    assert [i["rating_delta"] for i in group_items] == [None, None]

    # Режим «лучшая партия» тоже её отдаёт.
    client.patch("/api/users/me/profile", json={"history_mode": "best"}, headers=csrf_headers(client))
    best = client.get(f"/api/users/{me['id']}/matches").json()["items"]
    assert best[0]["rating_delta"] == 32.0