# ============================================================
# 审计 append-only 守护黄金测试（plan.md §3.6 / 矩阵 116 行剩余项）
# 覆盖：跨进程锁并发写不丢行、清理策略（保留窗口归档不删除证据）。
# ============================================================
from __future__ import annotations

import json
import threading
from pathlib import Path

from server.agent_core.audit_filelock import locked_append
from server.agent_core.audit_ledger import AnchorLedger
from server.agent_core.audit_mirror import AuditMirror


def _event(i: int) -> dict:
    return {"id": i, "at": "2026-08-01T00:00:00+08:00", "actor": "tester",
            "category": "TEST", "action": f"test.{i}", "target": {"type": "TEST"},
            "power": "P0", "rationale": {}, "evidenceRefs": [], "beforeSnapshot": None,
            "result": "SUCCESS", "prevHash": "GENESIS", "hash": "0" * 64}


def test_locked_append_concurrent_no_lost_lines(tmp_path: Path):
    """跨进程锁：4 线程×50 次并发 append 同一 JSONL，200 行全保留、无交错损坏。"""
    target = tmp_path / "shared.jsonl"

    def worker(n: int) -> None:
        for i in range(50):
            with locked_append(target) as fh:
                fh.write(json.dumps({"n": n, "i": i}, sort_keys=True) + "\n")

    threads = [threading.Thread(target=worker, args=(n,)) for n in range(4)]
    for t in threads:
        t.start()
    for t in threads:
        t.join()
    lines = target.read_text(encoding="utf-8").splitlines()
    assert len(lines) == 200, f"expected 200 lines, got {len(lines)}"
    for ln in lines:
        assert json.loads(ln), "行应为合法 JSON（无交错损坏）"


def test_ledger_archive_old_keeps_window_and_evidence(tmp_path: Path):
    """清理策略：超过保留窗口的旧锚定记录移入归档目录，主文件保留窗口；证据不丢失。"""
    ledger = AnchorLedger("tenant-a", "world-1", ledger_dir=str(tmp_path))
    evs = []
    for i in range(5):
        evs.append(_event(i + 1))
        ledger.append(evs, reason="test")
    assert ledger.status(evs)["records"] == 5

    r = ledger.archive_old(keep_last=2)
    assert r["archived"] == 3
    assert r["kept"] == 2
    assert len(ledger.read()) == 2

    archive = Path(r["archive"])
    assert archive.exists()
    archived_lines = archive.read_text(encoding="utf-8").splitlines()
    assert len(archived_lines) == 3
    # 归档记录仍是合法 JSON（分级存储，非删除）
    for ln in archived_lines:
        rec = json.loads(ln)
        assert rec.get("root") and rec.get("count")


def test_ledger_archive_under_window_is_noop(tmp_path: Path):
    """保留窗口内不归档（no-op），主文件不变。"""
    ledger = AnchorLedger("tenant-a", "world-1", ledger_dir=str(tmp_path))
    evs = []
    for i in range(3):
        evs.append(_event(i + 1))
        ledger.append(evs, reason="test")
    r = ledger.archive_old(keep_last=10)
    assert r["archived"] == 0
    assert r["kept"] == 3
    assert len(ledger.read()) == 3


def test_mirror_append_uses_cross_process_lock(tmp_path: Path):
    """镜像 append 经 locked_append 落盘：并发下仍完整（回归保护）。"""
    m = AuditMirror("tenant-a", "world-1", mirror_dir=str(tmp_path))
    threads = [
        threading.Thread(target=m.append_event, args=(_event(i + 1),))
        for i in range(5)
    ]
    for t in threads:
        t.start()
    for t in threads:
        t.join()
    assert m.count() == 5