"""A3 三分法流失 + B2 该回未回。"""
from __future__ import annotations

import pytest

from app.analytics import metrics
from app.db.models import Customer, MsgDailyStats, Staff

_NOW = 1756950000000  # 相对时间基准(绝对日期无关紧要,断言全部相对此值自洽)


def _cust(friend_id, *, last_chat=None, user_id="u1", delete=0, block=None):
    return Customer(friend_id=friend_id, channel="wechat",
                    owner_account_id="wx1", user_id=user_id,
                    last_chat_time=last_chat, delete_flag=delete, is_block=block)


async def _seed_churn(session):
    now = _NOW
    day_ms = 86_400_000
    session.add(Staff(user_id="u9", name="离职的", is_on_job=False))
    session.add(Staff(user_id="u1", name="在职的", is_on_job=True))
    # 真流失:45 天没聊 + 历史消息 ≥5
    session.add(_cust("c_real", last_chat=now - 45 * day_ms))
    # 历史消息不足 5 → 不算真流失
    session.add(_cust("c_few", last_chat=now - 45 * day_ms))
    # 只沉默 10 天 → 不入 30 档
    session.add(_cust("c_recent", last_chat=now - 10 * day_ms))
    # 从未激活
    session.add(_cust("c_null", last_chat=None))
    # 待交接:归属离职员工
    session.add(_cust("c_hand", user_id="u9", last_chat=now - 3 * day_ms))
    # 已删好友 → 全部剔除
    session.add(_cust("c_del", last_chat=now - 45 * day_ms, delete=1))
    # 历史消息量:real=6(≥5),few=2
    for peer, n in (("c_real", 6), ("c_few", 2)):
        session.add(MsgDailyStats(channel="wechat", owner_account_id="wx1",
                                  peer_kind="friend", peer_id=peer, day=20260601,
                                  send_cnt=n, recv_cnt=0, last_ts=now - 50 * day_ms,
                                  last_is_send=True))
    await session.commit()


async def test_churn_real_tier30(make_client, monkeypatch):
    monkeypatch.setattr(metrics, "_now_ms", lambda: _NOW)
    async def seed(session):
        await _seed_churn(session)
        page = await metrics.churn(session, channel="wechat", kind="real",
                                   tier=30, min_msgs=5, page=1, page_size=20)
        ids = [r["friend_id"] for r in page["items"]]
        assert "c_real" in ids and "c_few" not in ids
        assert "c_recent" not in ids and "c_del" not in ids
        real = next(r for r in page["items"] if r["friend_id"] == "c_real")
        assert real["hist_msgs"] == 6 and real["active_days"] == 1

    await make_client(seed)


async def test_churn_inactive_and_handover(make_client, monkeypatch):
    monkeypatch.setattr(metrics, "_now_ms", lambda: _NOW)
    async def seed(session):
        await _seed_churn(session)
        p1 = await metrics.churn(session, channel="wechat", kind="inactive",
                                 tier=30, min_msgs=5, page=1, page_size=20)
        assert {r["friend_id"] for r in p1["items"]} == {"c_null"}
        p2 = await metrics.churn(session, channel="wechat", kind="handover",
                                 tier=30, min_msgs=5, page=1, page_size=20)
        assert {r["friend_id"] for r in p2["items"]} == {"c_hand"}

    await make_client(seed)


async def test_churn_endpoint_422(make_client):
    async def seed(session):
        ...

    client = await make_client(seed)
    r = await client.get("/api/analytics/churn", params={"tier": 45})
    assert r.status_code == 422
    r2 = await client.get("/api/analytics/churn", params={"channel": "sms"})
    assert r2.status_code == 422


async def test_churn_tier_membership_and_min_msgs_boundary(make_client, monkeypatch):
    """tier60/90 会员资格([tier, next) 区间)+ min_msgs 恰等阈值的包含边界。"""
    monkeypatch.setattr(metrics, "_now_ms", lambda: _NOW)
    day_ms = 86_400_000

    async def seed(session):
        # 沉默 75 天:∈[60,90) → tier60 含、tier30 不含
        session.add(_cust("c75", last_chat=_NOW - 75 * day_ms))
        # 沉默 100 天:≥90 → tier90 含、tier60 不含
        session.add(_cust("c100", last_chat=_NOW - 100 * day_ms))
        # 历史消息恰好 5 条(=min_msgs,含边界)+ 沉默 45 天 → 入 tier30
        session.add(_cust("c5", last_chat=_NOW - 45 * day_ms))
        for peer, n in (("c75", 6), ("c100", 6), ("c5", 5)):
            session.add(MsgDailyStats(channel="wechat", owner_account_id="wx1",
                                      peer_kind="friend", peer_id=peer, day=20260601,
                                      send_cnt=n, recv_cnt=0,
                                      last_ts=_NOW - 110 * day_ms,
                                      last_is_send=True))
        await session.commit()

        t30 = await metrics.churn(session, channel="wechat", kind="real",
                                  tier=30, min_msgs=5, page=1, page_size=20)
        assert {r["friend_id"] for r in t30["items"]} == {"c5"}
        t60 = await metrics.churn(session, channel="wechat", kind="real",
                                  tier=60, min_msgs=5, page=1, page_size=20)
        assert {r["friend_id"] for r in t60["items"]} == {"c75"}
        t90 = await metrics.churn(session, channel="wechat", kind="real",
                                  tier=90, min_msgs=5, page=1, page_size=20)
        assert {r["friend_id"] for r in t90["items"]} == {"c100"}

    await make_client(seed)


async def test_churn_handover_excludes_null_user(make_client, monkeypatch):
    """user_id NULL(未映射归属)的客户不进待交接名单。"""
    monkeypatch.setattr(metrics, "_now_ms", lambda: _NOW)
    async def seed(session):
        session.add(Staff(user_id="u9", name="离职的", is_on_job=False))
        session.add(_cust("c_hand", user_id="u9"))
        session.add(_cust("c_nouser", user_id=None))
        await session.commit()
        p = await metrics.churn(session, channel="wechat", kind="handover",
                                tier=30, min_msgs=5, page=1, page_size=20)
        assert {r["friend_id"] for r in p["items"]} == {"c_hand"}

    await make_client(seed)


def test_next_tier_bad_tier_raises_value_error():
    """非法 tier 报 ValueError(与 churn 的 kind 分支报错类型一致)。"""
    with pytest.raises(ValueError):
        metrics._next_tier(45)
    assert metrics._next_tier(90) == 10_000  # 90 档=≥90 的开区间上限