"""T09 预审运行视图的只读存储：把装配好的 ScreeningRun 投影存下来供界面读取。

依据：docs/v2/03-detailed-design.md §9.2、BR-13；AC-12/30。

**不新建表**：复用既有 `assistant_objects`（新 kind `prescreen_run`），旧库结构不变。
运行视图是既有 run 对象的**只读投影**，因此这里只提供保存与读取，
不提供就地修改：要改结果必须产生新的运行修订（BR-13：过程修订不覆盖旧结果）。
"""

from __future__ import annotations

from contracts.prescreen import ScreeningRun
from services import assistant_store as store

KIND = "prescreen_run"


def save(db, screening: dict) -> dict:
    """保存一条已装配的运行视图；非契约形状直接拒绝，不落库。"""
    body = ScreeningRun(**screening).model_dump(mode="json")
    store.put(db, KIND, body, expected=screening.get("_expected_revision"))
    return body


def load(db, project_id: str, run_id: str) -> dict:
    """按项目读取运行视图。不存在或不属于该项目 → KeyError（由接口层转 404）。"""
    body = store.get(db, KIND, run_id)
    if body.get("project_id") != project_id:
        raise KeyError("运行不存在或不属于该项目")
    return body


def latest(db, project_id: str) -> dict | None:
    """项目最近一条运行视图；没有就返回 None，不编造空壳运行。"""
    rows = [item for item in store.listing(db, KIND, project_id)]
    if not rows:
        return None
    return max(rows, key=lambda item: (item.get("created_at") or "", item.get("revision") or 0))


def listing(db, project_id: str, limit: int = 20) -> list[dict]:
    """项目内运行视图，新的在前。用于界面选择要查看/推演的那一条运行。"""
    rows = [item for item in store.listing(db, KIND, project_id)]
    rows.sort(key=lambda item: (item.get("created_at") or "", item.get("revision") or 0),
              reverse=True)
    return rows[:limit]