"""Attention contributors for reviews, recurring, tech debt."""

from __future__ import annotations

from datetime import datetime, timezone

from steering.attention.context import AttentionEvalContext
from steering.attention.contributors.registry import (
    AttentionContributor,
    register_attention_contributor,
)


def _parse_due(value) -> datetime | None:
    if not value:
        return None
    if isinstance(value, datetime):
        return value if value.tzinfo else value.replace(tzinfo=timezone.utc)
    try:
        text = str(value).replace("Z", "+00:00")
        parsed = datetime.fromisoformat(text)
        return parsed if parsed.tzinfo else parsed.replace(tzinfo=timezone.utc)
    except ValueError:
        return None


def _reviews_due(ctx: AttentionEvalContext) -> list[dict]:
    if not ctx.eval_ctx or "reviews" not in ctx.eval_ctx.data_slices:
        return []
    now = datetime.now(timezone.utc)
    items: list[dict] = []
    for review in ctx.eval_ctx.reviews:
        if review.get("status") != "planned":
            continue
        due = _parse_due(review.get("due_at"))
        if due is None or due > now:
            continue
        items.append(
            {
                "kind": "review_due",
                "severity": "warning",
                "title": review.get("title") or "Review",
                "summary": "Review fällig",
                "scope_type": "review",
                "scope_id": str(review["id"]),
                "initiative_id": ctx.initiative_id,
                "review_id": str(review["id"]),
                "reason_code": "review_due",
            }
        )
    return items


def _recurring_due(ctx: AttentionEvalContext) -> list[dict]:
    if not ctx.eval_ctx or "recurring" not in ctx.eval_ctx.data_slices:
        return []
    now = datetime.now(timezone.utc)
    items: list[dict] = []
    for element in ctx.eval_ctx.recurring_elements:
        if element.get("status") != "active":
            continue
        due = _parse_due(element.get("next_due_at"))
        if due is None or due > now:
            continue
        items.append(
            {
                "kind": "recurring_due",
                "severity": "info",
                "title": element.get("title") or "Rhythmus",
                "summary": "Wiederkehrendes Element fällig",
                "scope_type": "recurring_element",
                "scope_id": str(element["id"]),
                "initiative_id": ctx.initiative_id,
                "recurring_element_id": str(element["id"]),
                "reason_code": "recurring_due",
            }
        )
    return items


def _action_review_required(ctx: AttentionEvalContext) -> list[dict]:
    if not ctx.eval_ctx or "reviews" not in ctx.eval_ctx.data_slices:
        return []
    planned_by_action = {
        str(review["action_id"])
        for review in ctx.eval_ctx.reviews
        if review.get("status") == "planned" and review.get("action_id")
    }
    items: list[dict] = []
    for action in ctx.actions:
        if action.get("status") != "review_required":
            continue
        action_id = str(action["id"])
        if action_id in planned_by_action:
            continue
        items.append(
            {
                "kind": "action_review_required",
                "severity": "warning",
                "title": action.get("title") or "Arbeitspaket",
                "summary": "Maßnahme wartet auf Review — kein geplantes Review verknüpft",
                "scope_type": "action",
                "scope_id": action_id,
                "initiative_id": ctx.initiative_id,
                "action_id": action_id,
                "reason_code": "action_review_required_no_review",
            }
        )
    return items


def _architecture_debt_stale(ctx: AttentionEvalContext) -> list[dict]:
    summary = ctx.read_models.get("tech_debt_summary") or {}
    if not summary.get("enabled") or not summary.get("stale_count"):
        return []
    return [
        {
            "kind": "architecture_debt_stale",
            "severity": "warning",
            "title": "Technische Schuld",
            "summary": (
                f"{summary['stale_count']} offene Schuld-Einträge älter als "
                f"{summary.get('stale_days', 30)} Tage ohne Fortschritt"
            ),
            "scope_type": "initiative",
            "scope_id": ctx.initiative_id,
            "initiative_id": ctx.initiative_id,
            "reason_code": "architecture_debt_stale",
        }
    ]


register_attention_contributor(
    AttentionContributor(key="review_due", contribute=_reviews_due)
)
register_attention_contributor(
    AttentionContributor(
        key="recurring_due",
        requires_elements=frozenset({"recurring_rhythm"}),
        contribute=_recurring_due,
    )
)
register_attention_contributor(
    AttentionContributor(key="action_review_required", contribute=_action_review_required)
)
register_attention_contributor(
    AttentionContributor(key="architecture_debt_stale", contribute=_architecture_debt_stale)
)