"""知识库消费指标单元测试（mock 数据，不依赖数据库）。"""
from types import SimpleNamespace
from unittest.mock import patch

from app.kb_metrics import kb_metrics, kb_metrics_overview


def _usage(agent_id, kb_id, chunk_id, segment_id, status="consumed"):
    return SimpleNamespace(agent_id=agent_id, kb_id=kb_id, chunk_id=chunk_id,
                           segment_id=segment_id, status=status, file_name="f.md",
                           heading="h", excerpt="e")


def _segment(sid, references=None, status="approved"):
    return SimpleNamespace(id=sid, status=status, references=references or [])


def _session(usage_rows, segments, kbs=()):
    def exec(*_a, **_k):
        # 简化：按调用顺序不可靠，直接用鸭子类型区分——这里用闭包计数不必要，
        # kb_metrics_overview 内部按顺序 exec 三次：usage / kbs / segments，
        # kb_metrics 内部两次：usage / segments。用可迭代队列处理。
        raise AssertionError("请使用带计划的 mock")

    return SimpleNamespace(exec=exec)


class _PlannedSession:
    def __init__(self, queues):
        self.queues = list(queues)

    def exec(self, *_a, **_k):
        return SimpleNamespace(all=lambda: self.queues.pop(0) if self.queues else [])

    def get(self, model, row_id):
        return None


def test_metrics_empty():
    session = _PlannedSession([[], []])
    report = kb_metrics(session)
    assert report["hit_rate"] == 0.0
    assert report["repeat_rate"] == 0.0
    assert report["reference_coverage"] == 0.0


def test_hit_rate_and_repeat_rate():
    usage = [
        _usage(1, 1, "c1", 101), _usage(1, 1, "c2", 101),
        _usage(2, 1, "c1", 102),
        # 重复消费：agent1 再次用 c1（segment 103）→ pair (1, c1) 两条
        _usage(1, 1, "c1", 103),
    ]
    session = _PlannedSession([usage, []])
    report = kb_metrics(session)
    assert report["detail"]["hit_requests"] == 3          # (1,101)(2,102)(1,103)
    assert report["detail"]["repeated_pairs"] == 1
    assert report["repeat_rate"] == round(1 / 3, 4)
    assert report["reference_coverage"] == 0.0            # 没有 segment 数据


def test_reference_coverage():
    usage = [_usage(1, 1, "c1", 101)]
    segments = [_segment(101, references=[{"file": "f"}]), _segment(102, references=[])]
    session = _PlannedSession([usage, segments])
    report = kb_metrics(session)
    assert report["reference_coverage"] == 0.5


def test_miss_requests_lower_hit_rate():
    usage = [_usage(1, 1, "c1", 101)]
    # 段 102 是已完成的生产段但完全没有消费记录 → 记一次未命中
    segments = [_segment(101, references=[{"x": 1}]), _segment(102)]
    session = _PlannedSession([usage, segments])
    report = kb_metrics(session)
    assert report["detail"]["search_requests"] == 2
    assert report["detail"]["miss_requests"] == 1
    assert report["hit_rate"] == 0.5


def test_overview_by_kb_sorted():
    usage = [
        _usage(1, 1, "c1", 101), _usage(1, 1, "c2", 101),
        _usage(1, 2, "c3", 102),
    ]
    kbs = [
        SimpleNamespace(id=1, name="主库", file_count=2, chunk_count=10),
        SimpleNamespace(id=2, name="副库", file_count=1, chunk_count=10),
    ]
    # kb_metrics_overview 先调 kb_metrics（usage, segments），再查 usage 和 kbs
    session = _PlannedSession([usage, [], usage, kbs])
    report = kb_metrics_overview(session)
    assert report["by_kb"][0]["kb_id"] == 1               # 消费比 0.2 > 0.1
    assert report["by_kb"][0]["consumed"] == 2
    assert report["top_chunks"][0]["chunk_id"] == "c1"    # c1 有 2 条记录（同 agent 两段）