# Copyright (c) 2026 Krzysztof Rudnicki. MIT licence.
"""The crown: who holds it, for how long, and what a tie does to a run."""

from __future__ import annotations

from typing import TYPE_CHECKING

from signal_bot.stats.streaks import (
    current_streaks,
    daily_winners,
    held_days,
    longest_ever,
    names_of,
)
from tests.stats_seed import ALA, BASIA, GROUP, KUHY, wrote

if TYPE_CHECKING:
    from signal_bot.store import Store


def test_no_history_has_no_crown(store: Store) -> None:
    winners = daily_winners(store.events, GROUP)
    assert winners == {}
    assert current_streaks(winners) == []
    assert longest_ever(winners) is None
    assert held_days(winners, "u-kuhy") == 0


def test_the_busiest_person_holds_the_day(store: Store) -> None:
    wrote(store, "2026-09-01", ALA, 10)
    wrote(store, "2026-09-01", KUHY, 5)
    winners = daily_winners(store.events, GROUP)
    assert names_of(winners["2026-09-01"]) == ["Ala"]


def test_a_tie_shares_the_crown(store: Store) -> None:
    """kuhy's call: shared, because the alternative starts arguments."""
    wrote(store, "2026-09-01", ALA, 4)
    wrote(store, "2026-09-01", KUHY, 4)
    wrote(store, "2026-09-01", BASIA, 1)
    winners = daily_winners(store.events, GROUP)
    assert names_of(winners["2026-09-01"]) == ["Ala", "kuhy"]


def test_a_tie_keeps_every_tied_run_alive(store: Store) -> None:
    """Three days, both tied throughout: both hold a three-day streak."""
    for day in ("2026-09-01", "2026-09-02", "2026-09-03"):
        wrote(store, day, ALA, 3)
        wrote(store, day, KUHY, 3)
    streaks = current_streaks(daily_winners(store.events, GROUP))
    assert [(s.display_name, s.length) for s in streaks] == [("Ala", 3), ("kuhy", 3)]


def test_a_run_survives_a_day_nobody_spoke(store: Store) -> None:
    """There was no crown to lose on a silent day, so the run continues."""
    wrote(store, "2026-09-01", KUHY, 5)
    # 09-02 and 09-03 silent.
    wrote(store, "2026-09-04", KUHY, 5)
    streaks = current_streaks(daily_winners(store.events, GROUP))
    assert [(s.display_name, s.length) for s in streaks] == [("kuhy", 2)]


def test_losing_a_day_ends_a_run_but_keeps_what_it_reached(store: Store) -> None:
    """The bug this test exists for reported every streak as zero."""
    wrote(store, "2026-09-01", ALA, 10)
    wrote(store, "2026-09-02", ALA, 10)
    wrote(store, "2026-09-03", ALA, 4)
    wrote(store, "2026-09-03", KUHY, 4)
    wrote(store, "2026-09-06", KUHY, 9)
    streaks = current_streaks(daily_winners(store.events, GROUP))
    assert [(s.display_name, s.length) for s in streaks] == [("kuhy", 2)]
    assert streaks[0].last_day == "2026-09-06"


def test_longest_ever_survives_the_run_that_set_it_ending(store: Store) -> None:
    wrote(store, "2026-09-01", ALA, 10)
    wrote(store, "2026-09-02", ALA, 10)
    wrote(store, "2026-09-03", ALA, 10)
    wrote(store, "2026-09-04", KUHY, 10)
    best = longest_ever(daily_winners(store.events, GROUP))
    assert (best.display_name, best.length, best.last_day) == ("Ala", 3, "2026-09-03")


def test_held_days_counts_shared_days_for_everyone_tied(store: Store) -> None:
    wrote(store, "2026-09-01", ALA, 10)
    wrote(store, "2026-09-02", ALA, 4)
    wrote(store, "2026-09-02", KUHY, 4)
    winners = daily_winners(store.events, GROUP)
    assert held_days(winners, "u-ala") == 2
    assert held_days(winners, "u-kuhy") == 1
    assert held_days(winners, "u-basia") == 0


def test_somebody_who_merely_took_part_holds_nothing(store: Store) -> None:
    """Neither leader nor tied: the common case, and the one worth pinning."""
    wrote(store, "2026-09-01", ALA, 10)
    wrote(store, "2026-09-01", KUHY, 4)
    wrote(store, "2026-09-01", BASIA, 1)
    winners = daily_winners(store.events, GROUP)
    assert names_of(winners["2026-09-01"]) == ["Ala"]
    assert held_days(winners, "u-basia") == 0


def test_streak_order_is_stable(store: Store) -> None:
    """Longest first, then by name -- not whichever the dict happened to yield."""
    wrote(store, "2026-09-01", ALA, 3)
    wrote(store, "2026-09-01", KUHY, 3)
    wrote(store, "2026-09-01", BASIA, 3)
    streaks = current_streaks(daily_winners(store.events, GROUP))
    assert [s.display_name for s in streaks] == ["Ala", "Basia", "kuhy"]


def test_the_backfilled_day_can_be_left_out(store: Store) -> None:
    wrote(store, "2026-08-30", ALA, 98)
    wrote(store, "2026-09-01", KUHY, 5)
    winners = daily_winners(store.events, GROUP, exclude="2026-08-30")
    assert "2026-08-30" not in winners
    assert [s.display_name for s in current_streaks(winners)] == ["kuhy"]