"""카카오톡 채널 신원 연결.

여기서 지키는 것은 하나다 — **연결되지 않은 발화자는 어떤 사장님도 되지 못한다.**
나머지 검사(코드 일회성·만료·시도 제한·재발급)는 전부 그 한 줄을 지탱한다.
"""

import uuid
from datetime import datetime, timedelta, timezone

import pytest
from sqlalchemy import text

from services import kakao_link_service as service
from services.kakao_link_service import KakaoLinkError


@pytest.fixture(autouse=True)
def channel(monkeypatch):
    """KAKAO_CHANNEL_PUBLIC_ID 가 있어야 기능이 열린다. 없는 경우는 따로 검사한다."""
    monkeypatch.setenv("KAKAO_CHANNEL_PUBLIC_ID", "_testCh")
    monkeypatch.setenv("KAKAO_LINK_CODE_TTL_MIN", "10")
    monkeypatch.setenv("KAKAO_LINK_MAX_ATTEMPTS", "3")


async def test_채널_설정이_없으면_기능_자체가_꺼진다(db_engine, monkeypatch):
    monkeypatch.setenv("KAKAO_CHANNEL_PUBLIC_ID", "")
    assert service.enabled() is False
    with pytest.raises(KakaoLinkError, match="KAKAO_LINK_DISABLED"):
        await service.issue_code(uuid.uuid4())
    # 화면은 자리를 그리되 버튼을 죽인다 — 상태 조회 자체는 살아 있어야 한다.
    assert (await service.state(uuid.uuid4()))["connection_enabled"] is False


async def test_코드는_한_번만_먹는다(db_engine):
    user_id, key = uuid.uuid4(), "kakao-key-1"
    code = (await service.issue_code(user_id))["code"]

    assert await service.redeem(code, key) == user_id
    # ★ 두 번째는 실패해야 한다. 같은 코드로 다른 카톡 계정이 붙으면 연결의 의미가 없다.
    with pytest.raises(KakaoLinkError, match="KAKAO_LINK_CODE_INVALID"):
        await service.redeem(code, "kakao-key-2")


async def test_연결된_발화자만_사장님이_된다(db_engine):
    user_id, key = uuid.uuid4(), "kakao-key-3"
    # ★ 이게 이 기능의 전부다 — 연결 전에는 어떤 값도 돌려주지 않는다.
    assert await service.resolve(key) is None
    await service.redeem((await service.issue_code(user_id))["code"], key)
    assert await service.resolve(key) == user_id
    assert await service.resolve("모르는-키") is None


async def test_만료된_코드는_안_먹는다(db_engine):
    user_id = uuid.uuid4()
    code = (await service.issue_code(user_id))["code"]
    async with db_engine.begin() as c:
        await c.execute(
            text("UPDATE owner_kakao_links SET code_expires_at = now() - interval '1 minute' WHERE user_id=:u"),
            {"u": user_id},
        )
    with pytest.raises(KakaoLinkError, match="KAKAO_LINK_CODE_INVALID"):
        await service.redeem(code, "kakao-key-4")


async def test_오입력_시도는_상한에서_끊긴다(db_engine):
    """짧은 코드(6자리)라 무차별 대입이 가능하다. 시도 수가 유일한 방어다."""
    user_id = uuid.uuid4()
    code = (await service.issue_code(user_id))["code"]
    async with db_engine.begin() as c:
        await c.execute(
            text("UPDATE owner_kakao_links SET code_attempts = 3 WHERE user_id=:u"), {"u": user_id}
        )
    with pytest.raises(KakaoLinkError, match="KAKAO_LINK_CODE_INVALID"):
        await service.redeem(code, "kakao-key-5")


async def test_재발급은_행을_늘리지_않고_옛_코드를_죽인다(db_engine):
    user_id = uuid.uuid4()
    first = (await service.issue_code(user_id))["code"]
    second = (await service.issue_code(user_id))["code"]
    assert first != second

    async with db_engine.begin() as c:
        rows = (
            await c.execute(
                text("SELECT count(*) FROM owner_kakao_links WHERE user_id=:u AND deleted=false"),
                {"u": user_id},
            )
        ).scalar_one()
    assert rows == 1

    # ★ 옛 코드가 살아 있으면 둘 중 어느 것이 먹을지 화면이 말해 줄 수 없다.
    with pytest.raises(KakaoLinkError, match="KAKAO_LINK_CODE_INVALID"):
        await service.redeem(first, "kakao-key-6")
    assert await service.redeem(second, "kakao-key-6") == user_id


async def test_이미_연결된_사장님은_코드를_다시_받지_않는다(db_engine):
    user_id = uuid.uuid4()
    await service.redeem((await service.issue_code(user_id))["code"], "kakao-key-7")
    with pytest.raises(KakaoLinkError, match="KAKAO_LINK_ALREADY"):
        await service.issue_code(user_id)


async def test_한_카카오_계정은_한_사장님에만_묶인다(db_engine):
    """없으면 같은 카톡 계정이 여러 사장님에 걸려 '어느 가게 이야기냐' 가 DB 에서 갈라진다."""
    first, second, key = uuid.uuid4(), uuid.uuid4(), "kakao-key-8"
    await service.redeem((await service.issue_code(first))["code"], key)
    code = (await service.issue_code(second))["code"]
    with pytest.raises(Exception):  # 부분 유니크 위반 — 연결 자체가 성립하지 않는다
        await service.redeem(code, key)
    assert await service.resolve(key) == first


async def test_해제하면_그_발화자는_다시_아무도_아니다(db_engine):
    user_id, key = uuid.uuid4(), "kakao-key-9"
    await service.redeem((await service.issue_code(user_id))["code"], key)
    await service.disconnect(user_id)
    assert await service.resolve(key) is None
    # 행은 남는다 — 지우면 누가 언제 연결했는지가 사라진다.
    async with db_engine.begin() as c:
        status = (
            await c.execute(
                text("SELECT status FROM owner_kakao_links WHERE user_id=:u"), {"u": user_id}
            )
        ).scalar_one()
    assert status == "REVOKED"
    # 해제한 뒤에는 다시 연결할 수 있어야 한다.
    await service.redeem((await service.issue_code(user_id))["code"], key)
    assert await service.resolve(key) == user_id


async def test_해제할_연결이_없으면_거절한다(db_engine):
    with pytest.raises(KakaoLinkError, match="KAKAO_LINK_NOT_FOUND"):
        await service.disconnect(uuid.uuid4())


async def test_상태는_코드_평문을_돌려주지_않는다(db_engine):
    user_id = uuid.uuid4()
    await service.issue_code(user_id)
    snapshot = await service.state(user_id)
    assert snapshot["status"] == "PENDING"
    assert snapshot["code_expires_at"]
    assert "code" not in snapshot


async def test_저장되는_것은_해시뿐이다(db_engine):
    user_id = uuid.uuid4()
    code = (await service.issue_code(user_id))["code"]
    async with db_engine.begin() as c:
        stored = (
            await c.execute(
                text("SELECT code_sha FROM owner_kakao_links WHERE user_id=:u"), {"u": user_id}
            )
        ).scalar_one()
    assert stored != code
    assert len(stored) == 64


async def test_라우터는_로그인_없이_열리지_않는다(client):
    for method, path in [
        ("get", "/v1/agent/kakao/link"),
        ("post", "/v1/agent/kakao/link/code"),
        ("post", "/v1/agent/kakao/link/disconnect"),
    ]:
        res = await getattr(client, method)(path)
        assert res.status_code in (401, 403), path


async def test_코드는_응답에서_한_번만_나가고_캐시되지_않는다(client, auth_headers):
    h = await auth_headers("kakao-owner")
    res = await client.post("/v1/agent/kakao/link/code", headers=h)
    assert res.status_code == 200
    assert res.json()["code"]
    assert res.headers["Cache-Control"] == "no-store"
    assert res.headers["Referrer-Policy"] == "no-referrer"

    state = await client.get("/v1/agent/kakao/link", headers=h)
    assert "code" not in state.json()


def test_코드에는_헷갈리는_글자가_없다():
    """잘못 읽어 실패하면 원인이 화면에 안 보이고 '연결이 안 된다' 로만 보인다."""
    assert not set("01OILl") & set(service._CODE_ALPHABET)
    assert len(service._new_code()) == service._CODE_LENGTH