"""Tests for tui_gateway JSON-RPC protocol plumbing."""

import io
import json
import sys
import threading
from unittest.mock import MagicMock, patch

import pytest

_original_stdout = sys.stdout


@pytest.fixture(autouse=True)
def _restore_stdout():
    yield
    sys.stdout = _original_stdout


@pytest.fixture()
def server():
    with patch.dict("sys.modules", {
        "hermes_constants": MagicMock(get_hermes_home=MagicMock(return_value="/tmp/hermes_test")),
        "hermes_cli.env_loader": MagicMock(),
        "hermes_cli.banner": MagicMock(),
        "hermes_state": MagicMock(),
    }):
        import importlib
        mod = importlib.import_module("tui_gateway.server")
        yield mod
        mod._sessions.clear()
        mod._pending.clear()
        mod._answers.clear()
        mod._methods.clear()
        importlib.reload(mod)


@pytest.fixture()
def capture(server):
    """Redirect server's real stdout to a StringIO and return (server, buf)."""
    buf = io.StringIO()
    server._real_stdout = buf
    return server, buf


# ── JSON-RPC envelope ────────────────────────────────────────────────


def test_unknown_method(server):
    resp = server.handle_request({"id": "1", "method": "bogus"})
    assert resp["error"]["code"] == -32601


def test_ok_envelope(server):
    assert server._ok("r1", {"x": 1}) == {
        "jsonrpc": "2.0", "id": "r1", "result": {"x": 1},
    }


def test_err_envelope(server):
    assert server._err("r2", 4001, "nope") == {
        "jsonrpc": "2.0", "id": "r2", "error": {"code": 4001, "message": "nope"},
    }


# ── write_json ───────────────────────────────────────────────────────


def test_write_json(capture):
    server, buf = capture
    assert server.write_json({"test": True})
    assert json.loads(buf.getvalue()) == {"test": True}


def test_write_json_broken_pipe(server):
    class _Broken:
        def write(self, _): raise BrokenPipeError
        def flush(self): raise BrokenPipeError

    server._real_stdout = _Broken()
    assert server.write_json({"x": 1}) is False


# ── _emit ────────────────────────────────────────────────────────────


def test_emit_with_payload(capture):
    server, buf = capture
    server._emit("test.event", "s1", {"key": "val"})
    msg = json.loads(buf.getvalue())

    assert msg["method"] == "event"
    assert msg["params"]["type"] == "test.event"
    assert msg["params"]["session_id"] == "s1"
    assert msg["params"]["payload"]["key"] == "val"


def test_emit_without_payload(capture):
    server, buf = capture
    server._emit("ping", "s2")

    assert "payload" not in json.loads(buf.getvalue())["params"]


# ── Blocking prompt round-trip ───────────────────────────────────────


def test_block_and_respond(capture):
    server, _ = capture
    result = [None]

    threading.Thread(
        target=lambda: result.__setitem__(0, server._block("test.prompt", "s1", {"q": "?"}, timeout=5)),
    ).start()

    for _ in range(100):
        if server._pending:
            break
        threading.Event().wait(0.01)

    rid = next(iter(server._pending))
    server._answers[rid] = "my_answer"
    server._pending[rid].set()

    threading.Event().wait(0.1)
    assert result[0] == "my_answer"


def test_clear_pending(server):
    ev = threading.Event()
    server._pending["r1"] = ev
    server._clear_pending()

    assert ev.is_set()
    assert server._answers["r1"] == ""


# ── Session lookup ───────────────────────────────────────────────────


def test_sess_missing(server):
    _, err = server._sess({"session_id": "nope"}, "r1")
    assert err["error"]["code"] == 4001


def test_sess_found(server):
    server._sessions["abc"] = {"agent": MagicMock()}
    s, err = server._sess({"session_id": "abc"}, "r1")

    assert s is not None
    assert err is None


# ── session.resume payload ────────────────────────────────────────────


def test_session_resume_returns_hydrated_messages(server, monkeypatch):
    class _DB:
        def get_session(self, _sid):
            return {"id": "20260409_010101_abc123"}

        def get_session_by_title(self, _title):
            return None

        def reopen_session(self, _sid):
            return None

        def get_messages(self, _sid):
            return [
                {"role": "user", "content": "hello"},
                {"role": "assistant", "content": "yo"},
                {"role": "tool", "content": "searched"},
                {"role": "assistant", "content": "   "},
                {"role": "assistant", "content": None},
                {"role": "narrator", "content": "skip"},
            ]

    monkeypatch.setattr(server, "_get_db", lambda: _DB())
    monkeypatch.setattr(server, "_make_agent", lambda sid, key, session_id=None: object())
    monkeypatch.setattr(server, "_init_session", lambda sid, key, agent, history, cols=80: None)
    monkeypatch.setattr(server, "_session_info", lambda _agent: {"model": "test/model"})

    resp = server.handle_request(
        {
            "id": "r1",
            "method": "session.resume",
            "params": {"session_id": "20260409_010101_abc123", "cols": 100},
        }
    )

    assert "error" not in resp
    assert resp["result"]["message_count"] == 3
    assert resp["result"]["messages"] == [
        {"role": "user", "text": "hello"},
        {"role": "assistant", "text": "yo"},
        {"role": "tool", "text": "searched"},
    ]


# ── Config I/O ───────────────────────────────────────────────────────


def test_config_load_missing(server, tmp_path):
    server._hermes_home = tmp_path
    assert server._load_cfg() == {}


def test_config_roundtrip(server, tmp_path):
    server._hermes_home = tmp_path
    server._save_cfg({"model": "test/model"})
    assert server._load_cfg()["model"] == "test/model"


# ── _cli_exec_blocked ────────────────────────────────────────────────


@pytest.mark.parametrize("argv", [
    [],
    ["setup"],
    ["gateway"],
    ["sessions", "browse"],
    ["config", "edit"],
])
def test_cli_exec_blocked(server, argv):
    assert server._cli_exec_blocked(argv) is not None


@pytest.mark.parametrize("argv", [
    ["version"],
    ["sessions", "list"],
])
def test_cli_exec_allowed(server, argv):
    assert server._cli_exec_blocked(argv) is None