# ============================================================
# round-39 黄金测试：trace 断链检测 + 可视化暴露（矩阵 114 剩余项）
# 覆盖：
#   1) verify_audit_trace：构造断链（哈希篡改/计数不一致/条目非法/格式非法）→ 检出 expected/actual
#   2) 端到端：schedule.run 真实审计 → 校验通过；篡改 traceChainHash → 检出
#   3) API：/api/gov/audit traceAlerts（断链列表/空数组）+ /api/gov/trace/verify 汇总
# ============================================================
from __future__ import annotations

import asyncio
import hashlib
import json

import pytest
from fastapi.testclient import TestClient

from server.agent_core.evidence import EvidenceItem, trace_chain, verify_audit_trace
from server.aps_domain.workflow import handle_intent
from server.contracts import IntentResult
from server.state.seed import seed_world


class _MemStore:
    def __init__(self, data):
        self.data = data

    def next_id(self, kind: str) -> int:
        key = "_c_" + kind
        self.data[key] = self.data.get(key, 0) + 1
        return self.data[key]

    def save(self):
        pass


def _mk_items():
    return [
        EvidenceItem(kind="schedule-version", ref="1", version="1"),
        EvidenceItem(kind="run", ref="run-1", runId="1", engine="RULE",
                     meta={"strategy": "COMPREHENSIVE", "solveStatus": "OPTIMAL", "gap": 0.0}),
        EvidenceItem(kind="algorithm", ref="RULE", version="RULE", inputsHash="abc123"),
    ]


def _trace_rationale(items, **overrides):
    chain = trace_chain(items)
    rat = {
        "traceChainHash": chain["chainHash"],
        "traceCount": chain["count"],
        "traceSummary": [{"kind": it["kind"], "ref": it["ref"]} for it in chain["items"]],
        "traceItems": chain["items"],
    }
    rat.update(overrides)
    return rat


def _algo_event(eid: int, rationale: dict, **overrides) -> dict:
    ev = {"id": eid, "at": "2026-08-02T10:00:00+08:00", "ts": "2026-08-02T10:00:00+08:00",
          "actor": "tester", "category": "ALGO_RUN", "action": "schedule.run",
          "target": {"type": "SCHEDULE_VERSION", "id": eid}, "power": "P1",
          "rationale": rationale, "prevHash": "GENESIS", "hash": "0" * 64}
    ev.update(overrides)
    return ev


# ---------------- 1) verify_audit_trace 纯函数 ----------------

def test_verify_audit_trace_ok_on_self_describing_record():
    ev = _algo_event(1, _trace_rationale(_mk_items()))
    result = verify_audit_trace([ev])
    assert result["ok"] is True
    assert result["checked"] == 1
    assert result["broken"] == []


def test_verify_audit_trace_detects_hash_tamper():
    items = _mk_items()
    ev = _algo_event(1, _trace_rationale(items, traceChainHash="f" * 64))
    result = verify_audit_trace([ev])
    assert result["ok"] is False
    (b,) = result["broken"]
    assert b["eventId"] == 1
    assert b["expected"] == "f" * 64
    assert b["actual"] == trace_chain(items)["chainHash"]   # 重算出的真实链哈希
    assert b["reason"] == "chain-hash-mismatch"


def test_verify_audit_trace_detects_count_mismatch():
    ev = _algo_event(2, _trace_rationale(_mk_items(), traceCount=2))
    result = verify_audit_trace([ev])
    assert result["ok"] is False
    b = result["broken"][0]
    assert b["eventId"] == 2
    assert b["reason"] == "count-mismatch"
    assert b["expected"] == "2"
    assert b["actual"] == "3"


def test_verify_audit_trace_detects_bad_summary_entry():
    rat = _trace_rationale(_mk_items())
    rat["traceSummary"][1] = {"kind": "hack", "ref": "x"}
    ev = _algo_event(3, rat)
    result = verify_audit_trace([ev])
    assert result["ok"] is False
    assert result["broken"][0]["reason"] == "bad-summary-entry"


def test_verify_audit_trace_detects_bad_hash_format():
    ev = _algo_event(4, _trace_rationale(_mk_items(), traceChainHash="zzz"))
    result = verify_audit_trace([ev])
    assert result["ok"] is False
    assert result["broken"][0]["reason"] == "bad-hash-format"


def test_verify_audit_trace_legacy_record_no_false_positive():
    """旧记录（无 traceItems，只有 traceChainHash/count/summary）仅结构校验，不误报。"""
    rat = _trace_rationale(_mk_items())
    rat.pop("traceItems")
    ev = _algo_event(5, rat)
    result = verify_audit_trace([ev])
    assert result["ok"] is True
    assert result["broken"] == []


# ---------------- 2) 端到端：schedule.run 真实审计 ----------------

def test_schedule_run_audit_verifies_then_tamper_detected():
    store = _MemStore(seed_world())

    async def _run():
        await handle_intent(store, "t", IntentResult(intent="schedule.run",
            params={"strategy": "COMPREHENSIVE", "engine": "RULE"},
            confidence=1.0, source="RULE_FAST"))

    asyncio.run(_run())
    runs = [e for e in store.data["auditEvents"]
            if e["category"] == "ALGO_RUN" and e["action"] == "schedule.run"]
    assert runs
    ev = runs[-1]
    assert isinstance(ev["rationale"].get("traceItems"), list), "traceItems 应落盘以便精确重算"

    result = verify_audit_trace(store.data["auditEvents"])
    assert result["ok"] is True

    tampered = json.loads(json.dumps(ev))
    tampered["rationale"]["traceChainHash"] = "0" * 64
    result2 = verify_audit_trace([tampered])
    assert result2["ok"] is False
    (b,) = result2["broken"]
    assert b["eventId"] == ev["id"]
    assert b["expected"] == "0" * 64
    assert b["actual"] == ev["rationale"]["traceChainHash"]
    assert b["reason"] == "chain-hash-mismatch"


# ---------------- 3) API：/api/gov/audit traceAlerts + /api/gov/trace/verify ----------------

class _ApiStore:
    def __init__(self, events):
        self.tenant_uuid = "platform"
        self.world_key = "default"
        self.data = {"auditEvents": events}

    def next_id(self, _kind: str) -> int:
        return 999

    def save(self) -> None:
        pass


def _signed_events(events):
    """把测试事件签名成哈希链一致（避免链告警干扰 traceAlerts 断言）。"""
    prev = "GENESIS"
    for ev in events:
        body = {k: v for k, v in ev.items() if k != "hash"}
        body["prevHash"] = prev
        ev["prevHash"] = prev
        ev["hash"] = hashlib.sha256(
            (prev + json.dumps(body, ensure_ascii=False, sort_keys=True)).encode("utf-8")
        ).hexdigest()
        prev = ev["hash"]
    return events


@pytest.fixture
def gov_client(monkeypatch, tmp_path):
    import os
    import server.gateway.app as gateway_module
    from tests.auth_provider import install_test_auth

    install_test_auth(monkeypatch, "tenant-trace-visual")
    os.environ["APS_AUDIT_LEDGER_DIR"] = str(tmp_path / "ledger")

    def _make(events):
        store = _ApiStore(_signed_events(events))
        monkeypatch.setattr(gateway_module, "get_store", lambda: store)
        c = TestClient(gateway_module.create_app())
        login = c.post("/api/auth/login", json={"username": "planner", "password": "test"})
        assert login.status_code == 200, login.text
        return c

    yield _make
    os.environ.pop("APS_AUDIT_LEDGER_DIR", None)


def test_gov_audit_trace_alerts_empty_when_clean(gov_client):
    c = gov_client([_algo_event(1, _trace_rationale(_mk_items()))])
    r = c.get("/api/gov/audit")
    assert r.status_code == 200, r.text
    body = r.json()
    assert body["traceAlerts"] == [], "无断链时 traceAlerts 应为空数组"
    assert body["traceOk"] is True
    assert body["traceChecked"] == 1

    r2 = c.get("/api/gov/trace/verify")
    assert r2.status_code == 200, r2.text
    v = r2.json()
    assert v["ok"] is True and v["checked"] == 1 and v["broken"] == []
    assert v["summary"]["broken"] == 0


def test_gov_audit_trace_alerts_nonempty_when_broken(gov_client):
    items = _mk_items()
    ev = _algo_event(1, _trace_rationale(items, traceChainHash="f" * 64))
    c = gov_client([ev])
    r = c.get("/api/gov/audit")
    assert r.status_code == 200, r.text
    body = r.json()
    assert body["traceOk"] is False
    assert len(body["traceAlerts"]) == 1
    b = body["traceAlerts"][0]
    assert b["eventId"] == 1
    assert b["expected"] == "f" * 64
    assert b["actual"] == trace_chain(items)["chainHash"]
    assert b["reason"] == "chain-hash-mismatch"

    r2 = c.get("/api/gov/trace/verify")
    assert r2.status_code == 200, r2.text
    v = r2.json()
    assert v["ok"] is False
    assert v["summary"]["broken"] == 1