"""Tests for join/branch topology — AP1.15c."""

from steering.graph.join_branch import (
    apply_deferred_topology,
    build_topology_metadata,
)
from steering.graph.roadmap_engine import compute_initiative_graph_state


def _item(item_id: str, status: str = "planned", **kwargs):
    return {
        "id": item_id,
        "status": status,
        "sort_order": kwargs.get("sort_order", 0),
        "sequencing_mode": kwargs.get("sequencing_mode", "sequential"),
        "title": kwargs.get("title", item_id),
    }


def test_optional_branch_does_not_block():
    items = [_item("join", "planned"), _item("opt", "planned"), _item("req", "planned")]
    deps = [
        {
            "from_item_id": "join",
            "to_item_id": "req",
            "dependency_type": "requires",
        },
        {
            "from_item_id": "join",
            "to_item_id": "opt",
            "dependency_type": "optional_branch",
        },
    ]
    state = compute_initiative_graph_state(items=items, dependencies=deps)
    assert state["items"]["join"]["blocked"] is True
    assert state["items"]["join"]["blocked_by"] == ["req"]
    assert "opt" not in state["items"]["join"]["blocked_by"]
    assert state["items"]["join"]["optional_prerequisites"] == ["opt"]


def test_parallel_group_metadata():
    items = [_item("a"), _item("b"), _item("c")]
    deps = [
        {
            "from_item_id": "b",
            "to_item_id": "c",
            "dependency_type": "parallel_group",
            "group_key": "phase-1",
        }
    ]
    topology = build_topology_metadata(dependencies=deps, item_by_id={i["id"]: i for i in items})
    assert set(topology["parallel_groups"]["phase-1"]) == {"b", "c"}


def test_apply_deferred_topology_strips_optional_blockers():
    item_by_id = {"x": _item("x"), "y": _item("y")}
    blocked_by_map = {"x": ["y", "z"]}
    deps = [
        {
            "from_item_id": "x",
            "to_item_id": "y",
            "dependency_type": "optional_branch",
        }
    ]
    result = apply_deferred_topology(
        dependencies=deps,
        item_by_id=item_by_id,
        blocked_by_map=blocked_by_map,
    )
    assert result["x"] == ["z"]