rpa_vision_v3/agent_v0/server_v1/safety_checks_provider.py

# agent_v0/server_v1/safety_checks_provider.py
"""SafetyChecksProvider — checks hybrides déclaratifs + LLM contextuels (QW4).

Pour une action pause_for_human :
- les checks déclaratifs (workflow) sont toujours inclus
- si safety_level == "medical_critical" et RPA_SAFETY_CHECKS_LLM_ENABLED=1,
  un appel LLM (medgemma:4b par défaut) ajoute jusqu'à N checks contextuels

Tout échec côté LLM (timeout, exception, parse) → additional_checks=[] :
le replay continue avec uniquement les déclaratifs (fallback safe).
"""

import base64
import json
import logging
import os
import uuid
from dataclasses import dataclass, field
from typing import Any, Dict, List, Optional

logger = logging.getLogger(__name__)


@dataclass
class PausePayload:
    checks: List[Dict[str, Any]] = field(default_factory=list)
    pause_reason: str = ""
    message: str = ""


def _env(name: str, default: str) -> str:
    return os.environ.get(name, default).strip()


def _env_int(name: str, default: int) -> int:
    try:
        return int(os.environ.get(name, default))
    except (TypeError, ValueError):
        return default


def _env_bool_enabled(name: str) -> bool:
    val = os.environ.get(name, "1").strip().lower()
    return val not in ("0", "false", "no", "off", "")


def build_pause_payload(
    action: Dict[str, Any],
    replay_state: Dict[str, Any],
    last_screenshot: Optional[str],
) -> PausePayload:
    """Construit le payload de pause enrichi pour une action pause_for_human."""
    params = action.get("parameters") or {}
    message = params.get("message", "Validation requise")
    safety_level = params.get("safety_level")
    declarative = params.get("safety_checks") or []

    # Normalisation des checks déclaratifs
    checks: List[Dict[str, Any]] = []
    for d in declarative:
        checks.append({
            "id": d.get("id") or f"decl_{uuid.uuid4().hex[:6]}",
            "label": d.get("label", "Validation"),
            "required": bool(d.get("required", True)),
            "source": "declarative",
            "evidence": None,
        })

    # Ajout LLM contextual si applicable
    if safety_level == "medical_critical" and _env_bool_enabled("RPA_SAFETY_CHECKS_LLM_ENABLED"):
        try:
            additional = _call_llm_for_contextual_checks(
                action=action,
                replay_state=replay_state,
                last_screenshot=last_screenshot,
                existing_labels=[c["label"] for c in checks],
            )
        except Exception as e:
            logger.warning("[BUS] lea:safety_checks_llm_failed reason=exception detail=%s", e)
            additional = []

        for a in additional:
            checks.append({
                "id": f"llm_{uuid.uuid4().hex[:6]}",
                "label": a.get("label", ""),
                "required": False,  # checks LLM = informationnels, pas obligatoires V1
                "source": "llm_contextual",
                "evidence": a.get("evidence", ""),
            })

    return PausePayload(
        checks=checks,
        pause_reason="",
        message=message,
    )


def _call_llm_for_contextual_checks(
    action: Dict[str, Any],
    replay_state: Dict[str, Any],
    last_screenshot: Optional[str],
    existing_labels: List[str],
) -> List[Dict[str, str]]:
    """Appelle Ollama en mode JSON strict pour générer 0-N checks contextuels.

    Returns:
        List[{label, evidence}] (max RPA_SAFETY_CHECKS_LLM_MAX_CHECKS).
        [] sur tout échec (timeout, JSON invalide, exception).
    """
    import requests

    # Défaut gemma4:latest : meilleur compromis détection/latence sur bench
    # 2026-05-06 (cf. docs/BENCH_SAFETY_CHECKS_2026-05-06.md). medgemma:4b
    # retournait systématiquement [] (refus de signaler).
    model = _env("RPA_SAFETY_CHECKS_LLM_MODEL", "gemma4:latest")
    # Timeout 7s : warm avg gemma4 = 2.9s + marge 4s. Cold start ~10s couvert
    # si le modèle reste résident (OLLAMA_KEEP_ALIVE=24h recommandé prod).
    timeout_s = _env_int("RPA_SAFETY_CHECKS_LLM_TIMEOUT_S", 7)
    max_checks = _env_int("RPA_SAFETY_CHECKS_LLM_MAX_CHECKS", 3)
    ollama_url = _env("OLLAMA_URL", "http://localhost:11434")

    params = action.get("parameters") or {}
    workflow_message = params.get("message", "")
    existing = ", ".join(existing_labels) if existing_labels else "aucun"

    prompt = f"""Tu es Léa, assistante médicale supervisée.
Avant de continuer le workflow, tu dois lister 0 à {max_checks} vérifications supplémentaires
que l'humain doit acquitter, en regardant l'écran actuel.

Contexte workflow : {workflow_message}
Checks déjà demandés : {existing}

NE répète PAS un check déjà demandé.
Si rien d'inhabituel à signaler, retourne {{"additional_checks": []}}.

Réponds UNIQUEMENT en JSON :
{{
  "additional_checks": [
    {{"label": "string court", "evidence": "ce que tu as vu d'inhabituel"}}
  ]
}}
"""

    payload = {
        "model": model,
        "prompt": prompt,
        "stream": False,
        "format": "json",
        "options": {"temperature": 0.1, "num_predict": 200},
    }

    if last_screenshot and os.path.isfile(last_screenshot):
        try:
            with open(last_screenshot, "rb") as f:
                payload["images"] = [base64.b64encode(f.read()).decode("ascii")]
        except Exception as e:
            logger.debug("safety_checks: lecture screenshot échouée (%s) — appel sans image", e)

    try:
        response = requests.post(
            f"{ollama_url}/api/generate",
            json=payload,
            timeout=timeout_s,
        )
        if response.status_code != 200:
            logger.warning("[BUS] lea:safety_checks_llm_failed reason=http_status detail=%s", response.status_code)
            return []
        text = response.json().get("response", "").strip()
    except requests.Timeout:
        logger.warning("[BUS] lea:safety_checks_llm_failed reason=timeout detail=%ss", timeout_s)
        return []
    except Exception as e:
        logger.warning("[BUS] lea:safety_checks_llm_failed reason=network detail=%s", e)
        return []

    # format=json garantit normalement du JSON valide
    try:
        parsed = json.loads(text)
    except json.JSONDecodeError as e:
        logger.warning("[BUS] lea:safety_checks_llm_failed reason=json_decode detail=%s", e)
        return []

    additional = parsed.get("additional_checks") or []
    if not isinstance(additional, list):
        return []

    # Filtre + tronc
    valid = []
    for item in additional[:max_checks]:
        if isinstance(item, dict) and item.get("label"):
            valid.append({
                "label": str(item["label"])[:200],
                "evidence": str(item.get("evidence", ""))[:300],
            })
    return valid