from __future__ import annotations

from collections.abc import Generator

from fastapi.testclient import TestClient
from sqlalchemy import create_engine, select
from sqlalchemy.orm import Session, sessionmaker
from sqlalchemy.pool import StaticPool

from app.api.deps import get_db
from app.db.base import Base
from app.main import create_app
from app.models.financial_record import ExpenseClaim
from app.services.agent_assets import AgentAssetService


def build_client() -> tuple[TestClient, sessionmaker[Session]]:
    engine = create_engine(
        "sqlite+pysqlite:///:memory:",
        connect_args={"check_same_thread": False},
        poolclass=StaticPool,
    )
    Base.metadata.create_all(bind=engine)
    session_factory = sessionmaker(bind=engine, autoflush=False, autocommit=False)
    app = create_app()

    def override_db() -> Generator[Session, None, None]:
        db = session_factory()
        try:
            yield db
        finally:
            db.close()

    app.dependency_overrides[get_db] = override_db
    return TestClient(app), session_factory


def test_orchestrator_routes_user_query_to_user_agent() -> None:
    client, _ = build_client()

    response = client.post(
        "/api/v1/orchestrator/run",
        json={
            "source": "user_message",
            "user_id": "pytest",
            "message": "客户A这个月还有多少应收",
            "context_json": {"role_codes": ["finance"]},
        },
    )

    assert response.status_code == 200
    payload = response.json()
    assert payload["selected_agent"] == "user_agent"
    assert payload["permission_level"] == "read"
    assert payload["status"] == "succeeded"
    assert payload["result"]["answer"]
    assert payload["result"]["suggested_actions"]
    assert payload["trace_summary"]["tool_count"] >= 1

    run_detail = client.get(f"/api/v1/agent-runs/{payload['run_id']}").json()
    assert run_detail["agent"] == "user_agent"
    assert run_detail["route_json"]["selected_agent"] == "user_agent"
    assert run_detail["semantic_parse"]["scenario"] == "accounts_receivable"
    assert run_detail["tool_calls"][0]["tool_type"] == "database"


def test_orchestrator_routes_schedule_to_hermes() -> None:
    client, session_factory = build_client()

    with session_factory() as db:
        task = next(
            item
            for item in AgentAssetService(db).list_assets(asset_type="task", status="active")
            if item.code == "task.hermes.daily_risk_scan"
        )

    response = client.post(
        "/api/v1/orchestrator/run",
        json={
            "source": "schedule",
            "task_id": task.id,
            "context_json": {"role_codes": ["finance"]},
        },
    )

    assert response.status_code == 200
    payload = response.json()
    assert payload["selected_agent"] == "hermes"
    assert payload["status"] == "succeeded"
    assert payload["trace_summary"]["tool_count"] == 2

    run_detail = client.get(f"/api/v1/agent-runs/{payload['run_id']}").json()
    assert run_detail["agent"] == "hermes"
    assert run_detail["route_json"]["selected_agent"] == "hermes"
    assert len(run_detail["tool_calls"]) == 2


def test_orchestrator_forbidden_request_does_not_call_downstream_agent() -> None:
    client, _ = build_client()

    response = client.post(
        "/api/v1/orchestrator/run",
        json={
            "source": "user_message",
            "user_id": "pytest",
            "message": "帮我直接付款给供应商B",
            "context_json": {"role_codes": ["user"]},
        },
    )

    assert response.status_code == 200
    payload = response.json()
    assert payload["selected_agent"] is None
    assert payload["permission_level"] == "forbidden"
    assert payload["status"] == "blocked"
    assert payload["trace_summary"]["tool_count"] == 0

    run_detail = client.get(f"/api/v1/agent-runs/{payload['run_id']}").json()
    assert run_detail["agent"] == "orchestrator"
    assert run_detail["tool_calls"] == []


def test_orchestrator_approval_required_returns_confirmation_result() -> None:
    client, _ = build_client()

    response = client.post(
        "/api/v1/orchestrator/run",
        json={
            "source": "user_message",
            "user_id": "pytest",
            "message": "帮我安排付款给供应商B",
            "context_json": {"role_codes": ["finance"]},
        },
    )

    assert response.status_code == 200
    payload = response.json()
    assert payload["selected_agent"] == "user_agent"
    assert payload["permission_level"] == "approval_required"
    assert payload["requires_confirmation"] is True
    assert payload["status"] == "blocked"
    assert "确认" in payload["result"]["message"]


def test_orchestrator_user_agent_draft_returns_structured_payload() -> None:
    client, session_factory = build_client()

    response = client.post(
        "/api/v1/orchestrator/run",
        json={
            "source": "user_message",
            "user_id": "pytest",
            "message": "帮我生成张三4月差旅报销草稿",
            "context_json": {"role_codes": ["finance"]},
        },
    )

    assert response.status_code == 200
    payload = response.json()
    assert payload["selected_agent"] == "user_agent"
    assert payload["status"] == "succeeded"
    assert payload["result"]["draft_payload"]["confirmation_required"] is True
    assert payload["result"]["draft_payload"]["claim_id"]
    assert payload["result"]["draft_payload"]["claim_no"].startswith("EXP-")
    assert payload["result"]["draft_payload"]["status"] == "draft"
    assert payload["result"]["suggested_actions"]

    with session_factory() as db:
        claim = db.scalar(
            select(ExpenseClaim).where(
                ExpenseClaim.id == payload["result"]["draft_payload"]["claim_id"]
            )
        )
        assert claim is not None
        assert claim.claim_no == payload["result"]["draft_payload"]["claim_no"]
        assert claim.status == "draft"
        assert claim.items


def test_orchestrator_treats_expense_narrative_as_draft_instead_of_ar_query() -> None:
    client, _ = build_client()

    response = client.post(
        "/api/v1/orchestrator/run",
        json={
            "source": "user_message",
            "user_id": "pytest",
            "message": "我今天去客户现场，招待了客户，花销了1000元",
            "context_json": {"role_codes": ["finance"]},
        },
    )

    assert response.status_code == 200
    payload = response.json()
    assert payload["selected_agent"] == "user_agent"
    assert payload["permission_level"] == "draft_write"
    assert payload["status"] == "blocked"
    assert payload["route_reason"] == "clarification_required"
    assert payload["trace_summary"]["scenario"] == "expense"
    assert payload["trace_summary"]["intent"] == "draft"
    assert payload["trace_summary"]["tool_count"] == 0
    assert "应收场景数据" not in payload["result"]["message"]
    assert "请补充" in payload["result"]["message"]


def test_orchestrator_tool_failure_is_logged_and_degraded() -> None:
    client, _ = build_client()

    response = client.post(
        "/api/v1/orchestrator/run",
        json={
            "source": "user_message",
            "user_id": "pytest",
            "message": "查一下本周报销金额",
            "context_json": {
                "role_codes": ["finance"],
                "simulate_tool_failure": "database",
            },
        },
    )

    assert response.status_code == 200
    payload = response.json()
    assert payload["selected_agent"] == "user_agent"
    assert payload["status"] == "succeeded"
    assert payload["trace_summary"]["failed_tool_count"] == 1
    assert payload["trace_summary"]["degraded"] is True

    run_detail = client.get(f"/api/v1/agent-runs/{payload['run_id']}").json()
    assert run_detail["tool_calls"][0]["status"] == "failed"
    assert "simulated database failure" in run_detail["tool_calls"][0]["error_message"]


def test_orchestrator_exception_is_written_to_agent_run() -> None:
    client, _ = build_client()

    response = client.post(
        "/api/v1/orchestrator/run",
        json={
            "source": "user_message",
            "user_id": "pytest",
            "message": "查一下本周报销金额",
            "context_json": {
                "role_codes": ["finance"],
                "simulate_orchestrator_exception": True,
            },
        },
    )

    assert response.status_code == 200
    payload = response.json()
    assert payload["status"] == "failed"

    run_detail = client.get(f"/api/v1/agent-runs/{payload['run_id']}").json()
    assert run_detail["status"] == "failed"
    assert "simulated orchestrator exception" in run_detail["error_message"]