"""Unit tests for AP2.0d NextAction execution-ready strategies."""

from __future__ import annotations

from steering.graph.execution_engine import compute_execution_graph_state
from steering.methods.registry import list_methods
from steering.strategies.next_action import register_builtin_strategies
from steering.strategies.next_action.execution_ready import (
    build_execution_ready_candidates,
    merge_candidates,
    rank_ready_action_ids,
)
from steering.strategies.next_action.registry import get_next_action_strategy


def _action(action_id: str, status: str = "open", **kwargs):
    return {
        "id": action_id,
        "initiative_id": kwargs.get("initiative_id", "init-1"),
        "status": status,
        "sort_order": kwargs.get("sort_order", 0),
        "title": kwargs.get("title", action_id),
        "action_kind": kwargs.get("action_kind", "delivery"),
        "roadmap_item_id": kwargs.get("roadmap_item_id"),
    }


def test_rank_ready_prefers_critical_path():
    actions = [
        _action("a", "done", sort_order=0),
        _action("b", "open", sort_order=1),
        _action("c", "open", sort_order=2),
    ]
    deps = [
        {
            "predecessor_action_id": "a",
            "successor_action_id": "b",
            "dependency_kind": "requires",
        },
        {
            "predecessor_action_id": "b",
            "successor_action_id": "c",
            "dependency_kind": "requires",
        },
    ]
    state = compute_execution_graph_state(actions=actions, dependencies=deps)
    ranked = rank_ready_action_ids(state, prefer_critical_path=True)
    assert ranked == ["b"]


def test_build_execution_ready_skips_blocked():
    actions = [
        _action("first", "open", sort_order=0),
        _action("second", "open", sort_order=1),
    ]
    state = compute_execution_graph_state(actions=actions, dependencies=[])
    candidates = build_execution_ready_candidates(
        actions=actions, graph_state=state, limit=5
    )
    assert len(candidates) == 1
    assert candidates[0]["action_id"] == "first"
    assert candidates[0]["reason_code"] in ("execution_ready", "execution_critical_path")


def test_critical_path_reason_code():
    actions = [
        _action("a", "done", sort_order=0),
        _action("b", "open", sort_order=1),
        _action("c", "open", sort_order=2),
    ]
    deps = [
        {
            "predecessor_action_id": "a",
            "successor_action_id": "b",
            "dependency_kind": "requires",
        },
        {
            "predecessor_action_id": "b",
            "successor_action_id": "c",
            "dependency_kind": "requires",
        },
    ]
    state = compute_execution_graph_state(actions=actions, dependencies=deps)
    candidates = build_execution_ready_candidates(
        actions=actions, graph_state=state, limit=5, prefer_critical_path=True
    )
    assert candidates[0]["reason_code"] == "execution_critical_path"


def test_merge_candidates_deduplicates_actions():
    first = [
        {
            "kind": "action",
            "action_id": "a1",
            "title": "A",
        }
    ]
    second = [
        {
            "kind": "action",
            "action_id": "a1",
            "title": "A duplicate",
        },
        {
            "kind": "review_milestone",
            "title": "Gate",
        },
    ]
    merged = merge_candidates(first, second, limit=5)
    assert len(merged) == 2
    assert merged[0]["action_id"] == "a1"
    assert merged[1]["kind"] == "review_milestone"


def test_ap20d_strategies_registered():
    register_builtin_strategies()
    for key in (
        "sequential_dependency",
        "maturity_progression",
        "recurring_control",
        "queue_pull",
        "continuous_product",
        "program_delivery",
    ):
        assert get_next_action_strategy(key) is not None


def test_ap20d_methods_wire_strategies():
    register_builtin_strategies()
    methods = {m.key: m for m in list_methods()}
    assert methods["sequential_dependency"].next_action_strategy_key == "sequential_dependency"
    assert methods["maturity_progression"].next_action_strategy_key == "maturity_progression"
    assert methods["recurring_control"].next_action_strategy_key == "recurring_control"
    assert methods["queue_pull"].next_action_strategy_key == "queue_pull"
    assert methods["continuous_product"].next_action_strategy_key == "continuous_product"
    assert methods["program_delivery"].next_action_strategy_key == "program_delivery"