"""Gate next actions proposal — sequential_dependency / program_delivery."""

from __future__ import annotations

from typing import Any

from steering.eval_context import SteeringEvalContext

COMMITTABLE = frozenset({"new", "triaged", "accepted"})
_PRIORITY = {"critical": 0, "high": 1, "normal": 2, "low": 3}


def _active_gate_id(ctx: SteeringEvalContext) -> str | None:
    if ctx.horizon.kind == "gate" and ctx.horizon.gate_roadmap_item_id:
        return str(ctx.horizon.gate_roadmap_item_id)
    debts = []
    return None


def _sort_key(item: dict[str, Any]) -> tuple:
    return (
        _PRIORITY.get(item.get("priority") or "normal", 9),
        item.get("sort_order") if item.get("sort_order") is not None else 9999,
        (item.get("title") or "").lower(),
    )


def propose_gate_next_actions(
    ctx: SteeringEvalContext,
    *,
    read_models: dict[str, Any] | None = None,
) -> list[dict[str, Any]]:
    read_models = read_models or {}
    gate_id = _active_gate_id(ctx)
    proposals: list[dict[str, Any]] = []
    rank = 0

    for debt in read_models.get("planning_debt") or []:
        rank += 1
        gid = str(debt.get("roadmap_item_id"))
        proposals.append(
            {
                "proposal_key": "gate_next_actions",
                "scope_type": "roadmap_item",
                "scope_id": gid,
                "rank": rank,
                "reason_code": "planning_debt",
                "summary": debt.get("message") or "Gate ohne Durchführungsplan",
                "title": debt.get("title") or "Zielzustand",
                "roadmap_item_id": gid,
                "initiative_id": ctx.initiative_id,
                "ranker_key": "heuristic_v0",
                "confidence": "heuristic",
                "factors": [{"code": "planning_debt", "weight": 100, "label": "Planning Debt"}],
                "dependency_refs": [],
                "dependency_blocked": False,
                "data_source": "steering_kernel",
            }
        )

    vocabulary = ctx.backlog_vocabulary
    convertible = frozenset(vocabulary.get("convertible_kinds") or ["story", "bug", "issue"])
    candidates = [
        item
        for item in ctx.backlog_items
        if item.get("status") in COMMITTABLE
        and item.get("item_kind") != "epic"
        and (item.get("item_kind") or "story") in convertible
        and (not gate_id or str(item.get("roadmap_item_id") or "") == gate_id)
    ]

    for item in sorted(candidates, key=_sort_key)[:15]:
        rank += 1
        proposals.append(
            {
                "proposal_key": "gate_next_actions",
                "scope_type": "backlog_item",
                "scope_id": str(item["id"]),
                "rank": rank,
                "reason_code": "gate_backlog_ready",
                "summary": "Eingang-Item am aktiven Gate committen",
                "title": item.get("title") or "Backlog-Item",
                "item_kind": item.get("item_kind") or "story",
                "priority": item.get("priority") or "normal",
                "roadmap_item_id": (
                    str(item["roadmap_item_id"]) if item.get("roadmap_item_id") else gate_id
                ),
                "initiative_id": ctx.initiative_id,
                "ranker_key": "heuristic_v0",
                "confidence": "heuristic",
                "factors": [
                    {
                        "code": "gate_alignment",
                        "weight": 50,
                        "label": "Gate-Zuordnung",
                    }
                ],
                "dependency_refs": [],
                "dependency_blocked": False,
                "data_source": "steering_kernel",
            }
        )

    return proposals


def gate_next_actions_attention_items(
    *,
    initiative_id: str,
    proposals: list[dict[str, Any]],
) -> list[dict[str, Any]]:
    backlog_ready = [p for p in proposals if p.get("scope_type") == "backlog_item"]
    if not backlog_ready:
        return []
    return [
        {
            "kind": "gate_commit_suggested",
            "severity": "info",
            "title": "Gate-Planung",
            "summary": f"{len(backlog_ready)} Item(s) für Gate-Commit vorgeschlagen",
            "scope_type": "initiative",
            "scope_id": initiative_id,
            "initiative_id": initiative_id,
            "reason_code": "gate_commit_suggested",
            "data_source": "gate_next_actions",
        }
    ]