"""rest.py — read-only REST mirror for the mobile app (plan §8, §13).

Bearer-token protected, mutations never exposed, same compact shapes and typed
errors as the MCP tools.  Tests use Starlette's TestClient (ASGI, no network).

Convention under test: the app resolves its read services via
``mcp_server.server.build_services`` — monkeypatched here (see conftest).
"""

import pytest
from fastapi import FastAPI
from starlette.testclient import TestClient

from mcp_server.errors import LabVoiceError

TOKEN = "app-bearer-token-123"
AUTH = {"Authorization": f"Bearer {TOKEN}"}


@pytest.fixture
def rest_settings(settings):
    settings.labvoice_rest_token = TOKEN
    return settings


@pytest.fixture
def rest_app(rest_settings, patch_build_services) -> FastAPI:
    patch_build_services()
    from mcp_server.rest import create_rest_app

    return create_rest_app(rest_settings)


@pytest.fixture
def api(rest_app) -> TestClient:
    return TestClient(rest_app)


# --- auth --------------------------------------------------------------------


def test_missing_token_is_rejected(api):
    assert api.get("/api/experiments").status_code == 401
    assert api.get("/api/experiments/123/state").status_code == 401
    assert api.get("/api/experiments/123/next-step").status_code == 401
    assert api.get("/api/templates").status_code == 401


def test_wrong_token_is_rejected(api):
    response = api.get("/api/experiments", headers={"Authorization": "Bearer nope"})
    assert response.status_code == 401


def test_correct_token_passes(api):
    response = api.get("/api/experiments", headers=AUTH)
    assert response.status_code == 200


def test_rest_app_requires_token_configured(settings, patch_build_services):
    patch_build_services()
    from mcp_server.rest import create_rest_app

    settings.labvoice_rest_token = None
    with pytest.raises(Exception) as excinfo:
        create_rest_app(settings)
    assert not isinstance(excinfo.value, NotImplementedError)


# --- endpoints ----------------------------------------------------------------


def test_find_experiments_returns_compact_summaries(api):
    response = api.get("/api/experiments", params={"q": "plasmid"}, headers=AUTH)
    assert response.status_code == 200
    payload = response.json()
    assert isinstance(payload, list) and payload
    summary = payload[0]
    assert summary["id"] == 123
    assert summary["title"] == "Plasmid prep"


def test_next_step_is_the_hot_path(api):
    """Plan §8: GET /api/experiments/{id}/next-step returns the parsed step + stock."""
    response = api.get("/api/experiments/123/next-step", headers=AUTH)
    assert response.status_code == 200
    payload = response.json()
    assert payload["experiment_id"] == 123
    assert payload["step"]["id"] == 9
    assert payload["step"]["finished"] is False
    assert payload["consumables"][0]["resource_key"] == "ethanol_absolute"
    assert payload["consumables"][0]["quantity"] == 2.0
    assert payload["stock"][0]["container_id"] == 31
    assert payload["stock"][0]["available"] == 50.0


def test_next_step_null_when_protocol_complete(api, client):
    for step in client.experiments[123].steps:
        step.finished = True
    response = api.get("/api/experiments/123/next-step", headers=AUTH)
    assert response.status_code == 200
    assert response.json() is None


def test_state_snapshot_shape(api):
    """Plan §8: `state` is what the app renders: title, steps, stock, next step."""
    response = api.get("/api/experiments/123/state", headers=AUTH)
    assert response.status_code == 200
    state = response.json()
    assert state["experiment_id"] == 123
    assert state["title"] == "Plasmid prep"
    assert state["unfinished_steps"] == [9, 10]
    next_step = state["next_step"]
    assert set(next_step) == {"experiment_id", "step", "consumables", "stock"}
    assert next_step["step"]["id"] == 9
    assert len(next_step["consumables"]) == 1
    assert {c["container_id"] for c in next_step["stock"]} == {31, 32}


def test_state_of_unknown_experiment_is_typed_error(api):
    response = api.get("/api/experiments/9999/state", headers=AUTH)
    assert response.status_code == 404
    payload = response.json()
    assert payload["error"] == "not_found"
    assert "message" in payload


def test_templates_endpoint_lists_summaries(api, client):
    from fakes import make_template

    client.templates[7] = make_template()
    response = api.get("/api/templates", headers=AUTH)
    assert response.status_code == 200
    templates = response.json()
    summary = templates[0]
    assert summary["id"] == 7
    assert summary["title"] == "PCR cleanup"
    assert "short_description" in summary
    assert summary["tags"] == ["dna", "cleanup"]


def test_templates_search_ranks(api, client):
    from fakes import make_template

    client.templates[7] = make_template()
    response = api.get("/api/templates", params={"q": "pcr"}, headers=AUTH)
    assert response.status_code == 200
    assert response.json()[0]["id"] == 7


# --- mutations are never exposed ----------------------------------------------


def test_no_mutation_routes_exist(rest_app):
    """Plan §8: mutations exist only as MCP tools so every mutation is journaled."""
    paths = rest_app.openapi().get("paths", {})
    assert paths, "REST app must document its endpoints"
    for path, operations in paths.items():
        for method in operations:
            assert method.lower() == "get", f"{method.upper()} {path} must not exist"


# --- unit-level helpers --------------------------------------------------------


def test_error_payload_shape():
    from mcp_server.rest import error_payload

    assert error_payload("clarification", "Which ethanol?") == {
        "error": "clarification",
        "message": "Which ethanol?",
    }


def test_verify_token_accepts_configured_token(rest_settings):
    from mcp_server.rest import verify_token

    assert verify_token(TOKEN) is None


def test_verify_token_rejects_wrong_token(rest_settings):
    from mcp_server.rest import verify_token

    with pytest.raises(LabVoiceError):
        verify_token("wrong")