app/backend/tests/flow/test_drafts.py

"""Editing writes drafts; only publishing changes what the engine reads."""

import asyncio
from pathlib import Path

import pytest

from fluksio.flow.controller import FlowController
from fluksio.flow.messages import MessageSpec
from fluksio.flow.schemas import FlowDef, NodeDef
from fluksio.flow.store import FlowStore, StaleVersion

SOURCE = "def process():\n    return {}\n"
EDITED = "def process():\n    return {'temp': 1}\n"


@pytest.fixture
def store(tmp_path: Path) -> FlowStore:
    return FlowStore(tmp_path / "flows")


def a_flow(title: str = "") -> FlowDef:
    return FlowDef(
        name="heating",
        title=title,
        nodes=[NodeDef(id="sensor", provides=[MessageSpec(name="temp")])],
    )


def test_a_draft_is_invisible_to_the_engine(store: FlowStore):
    store.write_draft(a_flow(), 0)

    assert store.has_draft("heating")
    assert store.list_flows() == ["heating"]  # the editor sees it
    assert store.read_all() == []  # the engine does not


def test_the_version_counter_advances_per_save(store: FlowStore):
    first = store.write_draft(a_flow(), 0)
    assert first.version == 1

    second = store.write_draft(a_flow(title="Warm"), first.version)
    assert second.version == 2


def test_resaving_identical_content_neither_bumps_nor_commits(store: FlowStore):
    stored = store.write_draft(a_flow(), 0)

    again = store.write_draft(a_flow(), stored.version)
    assert again.version == stored.version


def test_a_stale_write_is_refused(store: FlowStore):
    store.write_draft(a_flow(), 0)
    store.write_draft(a_flow(title="Mine"), 1)

    # A second client still holding version 1 must not overwrite version 2.
    with pytest.raises(StaleVersion) as excinfo:
        store.write_draft(a_flow(title="Theirs"), 1)
    assert excinfo.value.current == 2


def test_publishing_promotes_the_draft_and_its_sources(store: FlowStore):
    stored = store.write_draft(a_flow(title="Warm"), 0)
    store.write_node_source("heating", "sensor", EDITED, draft=True)

    published = store.publish_flow("heating", stored.version)

    assert published.title == "Warm"
    assert not store.has_draft("heating")
    assert store.read_flow("heating").title == "Warm"
    assert store.read_node_source("heating", "sensor") == EDITED
    assert [flow.name for flow in store.read_all()] == ["heating"]


def test_publishing_a_stale_draft_is_refused(store: FlowStore):
    store.write_draft(a_flow(), 0)

    with pytest.raises(StaleVersion):
        store.publish_flow("heating", 99)


def test_discarding_goes_back_to_what_is_running(store: FlowStore):
    store.write_flow(a_flow(title="Published"))
    store.write_node_source("heating", "sensor", SOURCE)
    store.write_draft(a_flow(title="Edited"), a_flow().version)
    store.write_node_source("heating", "sensor", EDITED, draft=True)

    restored = store.discard_draft("heating")

    assert restored.title == "Published"
    assert not store.has_draft("heating")
    assert store.read_node_source("heating", "sensor", draft=True) == SOURCE


def test_an_edited_source_alone_counts_as_a_draft(store: FlowStore):
    """Editing only code still has to be published before the engine runs it."""
    store.write_flow(a_flow())
    store.write_node_source("heating", "sensor", SOURCE)

    store.write_node_source("heating", "sensor", EDITED, draft=True)

    assert store.has_draft("heating")
    assert store.read_node_source("heating", "sensor") == SOURCE
    assert store.read_node_source("heating", "sensor", draft=True) == EDITED

    store.publish_flow("heating", store.read_flow("heating").version)
    assert store.read_node_source("heating", "sensor") == EDITED


def test_a_published_node_with_no_body_is_reported(store: FlowStore):
    """It would run the new-node template, which returns nothing and says so."""
    store.write_flow(a_flow())
    controller = FlowController(store)

    asyncio.run(controller.reload())
    (issue,) = [i for i in controller.issues if i.code == "missing_source"]
    assert issue.node == "heating.sensor"
    assert not issue.advisory
    # It still loads: one node with no body does not take the flow down.
    assert controller.get_node("heating.sensor") is not None

    store.write_node_source("heating", "sensor", SOURCE)
    asyncio.run(controller.reload())
    assert [i for i in controller.issues if i.code == "missing_source"] == []


def test_a_node_being_written_in_the_editor_is_not_reported(store: FlowStore):
    """A draft legitimately has no published body yet — that is what a draft is."""
    store.write_draft(a_flow(), 0)
    controller = FlowController(store)

    assert controller.preview("heating").issues == []


def test_resaving_the_published_source_creates_no_draft(store: FlowStore):
    store.write_flow(a_flow())
    store.write_node_source("heating", "sensor", SOURCE)

    assert store.write_node_source("heating", "sensor", SOURCE, draft=True) is False
    assert not store.has_draft("heating")


def test_renaming_carries_the_draft_and_repoints_other_drafts(store: FlowStore):
    store.write_draft(a_flow(), 0)
    store.write_draft(
        FlowDef(
            name="display",
            nodes=[NodeDef(id="gauge", requires=[MessageSpec(name="heating.temp")])],
        ),
        0,
    )

    renamed = store.rename_flow("heating", "warmth")

    assert renamed.name == "warmth"
    assert store.has_draft("warmth")
    assert store.read_flow("display", draft=True).nodes[0].requires[0].name == (
        "warmth.temp"
    )