"""Unit tests for oracle_commands' pure rune-draw logic.

Heavy imports (discord, ai_functions) are stubbed only when genuinely absent,
matching the pytest-only unit CI job.
"""
import random
import sys
import types


def _stub_if_missing(name, build):
    if name in sys.modules:
        return
    try:
        __import__(name)
    except ImportError:
        sys.modules[name] = build()


def _build_discord():
    mod = types.ModuleType("discord")

    class Object:
        def __init__(self, id=None):  # noqa: A002
            self.id = id

    mod.Object = Object
    ext = types.ModuleType("discord.ext")
    commands = types.ModuleType("discord.ext.commands")

    class Cog:
        pass

    commands.Cog = Cog
    commands.hybrid_command = lambda **_k: (lambda fn: fn)
    ext.commands = commands
    mod.ext = ext
    sys.modules["discord.ext"] = ext
    sys.modules["discord.ext.commands"] = commands
    return mod


def _build_ai_functions():
    mod = types.ModuleType("ai_functions")

    async def handle_response(*_a, **_k):
        return ("stub reading", [])

    mod.handle_response = handle_response
    return mod


_stub_if_missing("discord", _build_discord)
_stub_if_missing("ai_functions", _build_ai_functions)

import oracle_commands  # noqa: E402  (after stubbing)


def test_full_elder_futhark_present():
    assert len(oracle_commands.RUNES) == 24
    # every rune has the required fields
    for r in oracle_commands.RUNES:
        assert {"symbol", "nazwa", "znaczenie", "odwrocone"} <= set(r)


def test_draw_returns_distinct_runes():
    drawn = oracle_commands.draw_runes(3, random.Random(1))
    names = [r["nazwa"] for r, _ in drawn]
    assert len(names) == 3
    assert len(set(names)) == 3  # distinct


def test_non_invertible_runes_are_never_reversed():
    # Run many draws of the whole deck; any rune with empty 'odwrocone' must
    # never come up reversed.
    for seed in range(200):
        for rune, reversed_ in oracle_commands.draw_runes(24, random.Random(seed)):
            if not rune["odwrocone"]:
                assert reversed_ is False, f"{rune['nazwa']} was reversed but is non-invertible"


def test_runa_dnia_is_stable_per_user_per_day():
    # Same user + same day -> identical draw; different day -> RNG differs.
    r1 = oracle_commands.draw_runes(1, oracle_commands._rng_for_day(42, "2026-07-31"))[0]
    r2 = oracle_commands.draw_runes(1, oracle_commands._rng_for_day(42, "2026-07-31"))[0]
    assert r1[0]["nazwa"] == r2[0]["nazwa"] and r1[1] == r2[1]

    seeds = {
        oracle_commands._rng_for_day(uid, "2026-07-31").random()
        for uid in range(50)
    }
    assert len(seeds) > 1  # different users get different streams


def test_meaning_falls_back_to_upright_for_non_invertible():
    gebo = next(r for r in oracle_commands.RUNES if r["nazwa"] == "Gebo")
    # even if asked "reversed", a non-invertible rune yields its upright meaning
    assert oracle_commands._meaning(gebo, True) == gebo["znaczenie"]