"""Utility helpers for signal planner service."""

from __future__ import annotations

from .shared import Any, Optional, Signal, json


class SignalPlannerUtilsMixin:
    """Type-safe conversion and fallback builder helpers."""

    @staticmethod
    def _as_dict(value: Any) -> dict[str, Any]:
        if isinstance(value, dict):
            return dict(value)
        if isinstance(value, str):
            try:
                parsed = json.loads(value)
                return parsed if isinstance(parsed, dict) else {}
            except Exception:
                return {}
        return {}

    @staticmethod
    def _safe_int(value: Any) -> Optional[int]:
        try:
            return int(str(value).strip())
        except (TypeError, ValueError, AttributeError):
            return None

    @staticmethod
    def _safe_float(value: Any) -> Optional[float]:
        try:
            return float(value)
        except (TypeError, ValueError):
            return None

    @classmethod
    def _resolve_outbox_targets(
        cls,
        *,
        signal: Signal,
        source_message_id: Optional[str],
        source_chat_id: Optional[str],
    ) -> tuple[Optional[str], Optional[str]]:
        strategic = cls._as_dict(signal.strategic_analysis)
        source_context = (
            strategic.get("source_context")
            if isinstance(strategic.get("source_context"), dict)
            else {}
        )
        resolved_chat_id = (
            str(source_chat_id or "").strip()
            or str(source_context.get("source_chat_id") or "").strip()
            or str(source_context.get("chat_id") or "").strip()
            or str(source_context.get("channel_ref") or "").strip()
            or str(source_context.get("group_chat_id") or "").strip()
            or None
        )
        resolved_source_message_id = (
            str(source_message_id or "").strip()
            or str(source_context.get("source_message_id") or "").strip()
            or str(source_context.get("message_id") or "").strip()
            or None
        )
        return resolved_chat_id, resolved_source_message_id

    @classmethod
    def _pick_fallback_assignee_user_id(
        cls,
        *,
        members: list[dict[str, Any]],
    ) -> Optional[int]:
        candidates: list[tuple[float, int]] = []
        for item in members:
            uid = cls._safe_int(item.get("user_id"))
            workload_ratio = cls._safe_float(item.get("workload_ratio"))
            if uid is None:
                continue
            candidates.append((float(workload_ratio if workload_ratio is not None else 1000.0), int(uid)))
        if not candidates:
            return None
        candidates.sort(key=lambda row: (row[0], row[1]))
        return int(candidates[0][1])

    @classmethod
    def _build_fallback_planner_result(
        cls,
        *,
        signal: Signal,
        members: list[dict[str, Any]],
        reason: str,
    ) -> dict[str, Any]:
        fallback_assignee = cls._pick_fallback_assignee_user_id(members=members)
        summary_seed = (
            str(signal.summary or "").strip()
            or str(signal.title or "").strip()
            or str(signal.content or "").strip()
            or "信号已入库，模型结构化输出异常，已自动降级生成初始执行建议。"
        )
        execution_plan: list[dict[str, Any]] = [
            {
                "step": "澄清信号目标与边界",
                "owner_user_id": fallback_assignee,
                "eta": "4h",
            },
            {
                "step": "拆解最小可执行任务并确认优先级",
                "owner_user_id": fallback_assignee,
                "eta": "1d",
            },
        ]
        return {
            "summary": summary_seed[:180],
            "priority": str(signal.priority or "medium").strip() or "medium",
            "execution_plan": execution_plan,
            "risks": [
                "模型返回非预期结构，已使用降级策略生成建议，请人工复核。",
            ],
            "confidence": 0.2,
            "assignee_user_id": fallback_assignee,
            "assignee_reason": "按当前最低负载成员自动指派（降级模式）",
            "fallback_reason": str(reason or "structured_schema_invalid")[:200],
            "fallback_mode": True,
        }