"""adapters/telemetry.py 单元测试 — SQLiteTelemetryRecorder。"""

from __future__ import annotations

import sqlite3
import uuid

import pytest

from adapters.telemetry import SQLiteTelemetryRecorder
from core.protocols import TelemetryRecorder

# ---------------------------------------------------------------------------
# Fixtures
# ---------------------------------------------------------------------------


@pytest.fixture()
def db_path(tmp_path):
    """返回临时数据库路径。"""
    return tmp_path / "telemetry_test.db"


@pytest.fixture()
def recorder(db_path):
    """构造 SQLiteTelemetryRecorder 实例。"""
    return SQLiteTelemetryRecorder(db_path=db_path)


def _make_call_kwargs(*, cache_hit: bool = False, error: str | None = None):
    """构造 record_llm_call 的标准参数字典。"""
    return dict(
        call_id=str(uuid.uuid4()),
        parent_call_id=None,
        session_id="sess-001",
        model_name="gpt-4o",
        provider="openai",
        messages='[{"role":"user","content":"hi"}]',
        response="hello",
        thinking="",
        prompt_tokens=10,
        completion_tokens=5,
        latency_ms=120,
        ttft_ms=45.2,
        max_inter_token_ms=12.3,
        cache_hit=cache_hit,
        error=error,
    )


# ---------------------------------------------------------------------------
# Tests
# ---------------------------------------------------------------------------


def test_satisfies_protocol(recorder):
    """SQLiteTelemetryRecorder 满足 TelemetryRecorder Protocol。"""
    assert isinstance(recorder, TelemetryRecorder)


@pytest.mark.asyncio
async def test_record_creates_table_and_inserts(recorder, db_path):
    """首次写入应懒创建表并成功插入一条记录。"""
    kwargs = _make_call_kwargs()
    await recorder.record_llm_call(**kwargs)

    conn = sqlite3.connect(str(db_path))
    conn.row_factory = sqlite3.Row
    rows = conn.execute("SELECT * FROM llm_calls").fetchall()
    conn.close()

    assert len(rows) == 1
    row = rows[0]
    assert row["call_id"] == kwargs["call_id"]
    assert row["model_name"] == "gpt-4o"
    assert row["prompt_tokens"] == 10
    assert row["completion_tokens"] == 5
    assert row["cache_hit"] == 0  # False → INTEGER 0
    assert row["error"] is None
    assert row["created_at"] is not None


@pytest.mark.asyncio
async def test_record_with_error(recorder, db_path):
    """error 字段非 None 时应正确存储。"""
    kwargs = _make_call_kwargs(error="RateLimitError: 429")
    await recorder.record_llm_call(**kwargs)

    conn = sqlite3.connect(str(db_path))
    conn.row_factory = sqlite3.Row
    row = conn.execute(
        "SELECT error FROM llm_calls WHERE call_id = ?", (kwargs["call_id"],)
    ).fetchone()
    conn.close()

    assert row["error"] == "RateLimitError: 429"


@pytest.mark.asyncio
async def test_record_cache_hit(recorder, db_path):
    """cache_hit=True 时应存储为 INTEGER 1。"""
    kwargs = _make_call_kwargs(cache_hit=True)
    await recorder.record_llm_call(**kwargs)

    conn = sqlite3.connect(str(db_path))
    conn.row_factory = sqlite3.Row
    row = conn.execute(
        "SELECT cache_hit FROM llm_calls WHERE call_id = ?", (kwargs["call_id"],)
    ).fetchone()
    conn.close()

    assert row["cache_hit"] == 1


@pytest.mark.asyncio
async def test_duplicate_call_id_does_not_raise(recorder, db_path):
    """重复 call_id 写入应静默忽略（INSERT OR IGNORE），不抛异常。"""
    kwargs = _make_call_kwargs()
    await recorder.record_llm_call(**kwargs)
    await recorder.record_llm_call(**kwargs)
    conn = sqlite3.connect(str(db_path))
    rows = conn.execute("SELECT COUNT(*) FROM llm_calls").fetchone()
    conn.close()
    assert rows[0] == 1


@pytest.mark.asyncio
async def test_db_error_does_not_propagate(tmp_path):
    """SQLite 写入失败时 record_llm_call 应静默降级，不抛异常。"""
    bad_recorder = SQLiteTelemetryRecorder(db_path=tmp_path / "nonexistent_dir" / "bad.db")
    kwargs = _make_call_kwargs()
    await bad_recorder.record_llm_call(**kwargs)


@pytest.mark.asyncio
async def test_concurrent_writes_no_lock_error(recorder, db_path):
    """16 路并发 record_llm_call 应全部成功，无 database is locked 错误。"""
    import asyncio

    tasks = []
    for _ in range(16):
        kwargs = _make_call_kwargs()
        tasks.append(recorder.record_llm_call(**kwargs))
    await asyncio.gather(*tasks)
    conn = sqlite3.connect(str(db_path))
    count = conn.execute("SELECT COUNT(*) FROM llm_calls").fetchone()[0]
    conn.close()
    assert count == 16


def test_high_concurrency_writes_zero_loss(recorder, db_path):
    """64 路线程并发直压 _write 应零丢失——复现生产 concurrency 下 database is locked 丢失。

    直接压同步 _write（不经 to_thread 排队），最大化并发连接数以逼出锁竞争；
    单连接 + threading.Lock 串行化模式下应全部落库、零丢失（对齐 HarnessLog）。
    """
    import concurrent.futures

    n = 64
    kwargs_list = [_make_call_kwargs() for _ in range(n)]
    with concurrent.futures.ThreadPoolExecutor(max_workers=n) as executor:
        list(executor.map(lambda kw: recorder._write(**kw), kwargs_list))

    conn = sqlite3.connect(str(db_path))
    count = conn.execute("SELECT COUNT(*) FROM llm_calls").fetchone()[0]
    conn.close()
    assert count == n, f"并发写丢失 {n - count} 条（database is locked 降级丢弃）: 落库 {count}/{n}"


def test_uses_single_persistent_connection(db_path, monkeypatch):
    """对齐 HarnessLog：单持久连接（构造时建一次），写入复用而非每次新建。

    每次写新建连接是并发锁竞争根源（多连接争 SQLite 写锁，撑爆 busy_timeout）；
    单连接 + 进程内 Lock 串行化把并发控制拉到进程内，消除 SQLite 层锁竞争。
    """
    connect_calls = {"n": 0}
    real_connect = sqlite3.connect

    def _counting_connect(*args, **kwargs):
        connect_calls["n"] += 1
        return real_connect(*args, **kwargs)

    monkeypatch.setattr(sqlite3, "connect", _counting_connect)

    recorder = SQLiteTelemetryRecorder(db_path=db_path)
    after_init = connect_calls["n"]
    for _ in range(10):
        recorder._write(**_make_call_kwargs())
    after_writes = connect_calls["n"]

    assert after_init >= 1, "构造时应建立持久连接（对齐 HarnessLog）"
    assert after_writes == after_init, (
        f"写入期间新建了 {after_writes - after_init} 个连接（应复用单持久连接，"
        "每次新连接是并发锁竞争根源）"
    )