"""Uniform stdin parsing for the memory plugin hooks (deep module).

Replaces four inline stdin parsers and the python3-vs-jq inconsistency with a
single read_input() returning a HookInput dataclass. Fail-open: malformed or
empty stdin yields empty-string fields, never an exception. Per-hook fallback
semantics (e.g. 'unknown' defaults, PID fallback) are applied by each hook, not
here, to stay faithful to the original bash behavior.
"""
from __future__ import annotations

import json
import sys
from dataclasses import dataclass


@dataclass(frozen=True)
class HookInput:
    session_id: str
    cwd: str
    file_path: str
    reason: str
    source: str
    raw: dict


def read_input() -> "HookInput":
    data = {}
    try:
        raw = sys.stdin.read()
        data = json.loads(raw) if raw.strip() else {}
    except Exception:
        data = {}
    if not isinstance(data, dict):
        data = {}

    tool_input = data.get("tool_input") or {}
    if not isinstance(tool_input, dict):
        tool_input = {}

    return HookInput(
        session_id=str(data.get("session_id", "") or ""),
        cwd=str(data.get("cwd", "") or ""),
        file_path=str(tool_input.get("file_path", "") or ""),
        reason=str(data.get("reason", "") or ""),
        source=str(data.get("source", "") or ""),
        raw=data,
    )