"""Standalone CRA cyber risk-assessment endpoint.

POST /api/v1/cra/assess — takes the findings the external repo-scanner already
produced and returns the deterministic CRA assessment: each finding mapped to
the CRA Annex I requirement(s) it violates, a risk level, the curated CRA
measures, and the NIST 800-53 / OWASP Top 10 golden-set crosswalk.

Project-less by design: works standalone for ANY customer — including those with
no CE risk assessment and no FMEA yet (the mandatory baseline). Reuses the fully
tested mapper; no DB, no LLM, no RAG. Same logic the MCP server exposes.
"""
from typing import Dict, List, Optional

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel

from compliance.services.cra_finding_mapper import assess_findings_payload
from compliance.services.cra_snapshot_store import save_snapshot, list_snapshots, get_snapshot
from compliance.services.cra_use_case_controls import enrich_findings_with_breadth
from compliance.services.cra_component_findings import findings_from_components
from compliance.api.cra_annex_i_data import ANNEX_I_REQUIREMENTS, MEASURES, DEADLINES
from compliance.api.cra_routes import _classify  # reuse the deterministic Annex III/IV classifier
from compliance.services.use_case_controls import UseCaseControlsService
from database import SessionLocal
from .tenant_utils import get_tenant_id

router = APIRouter(prefix="/v1/cra", tags=["cra"])


class FindingIn(BaseModel):
    id: str
    title: Optional[str] = ""
    description: Optional[str] = ""
    category: Optional[str] = ""
    cwe: Optional[str] = ""
    severity: Optional[str] = ""
    cvss: Optional[float] = None
    location: Optional[str] = ""
    safety_impact: Optional[bool] = False
    exploited: Optional[bool] = False


class SafetyFunctionIn(BaseModel):
    name: str
    hazard: Optional[str] = ""
    original_measure: Optional[str] = ""
    kind: Optional[str] = ""               # prevent_unexpected_actuation | signal_integrity
    vulnerable_to: Optional[List[str]] = None


class ComponentIn(BaseModel):
    name: str
    component_class: Optional[str] = ""   # controller | hmi | gateway | drive | remote_access | sensor
    networked: Optional[bool] = False
    vendor: Optional[str] = ""
    product: Optional[str] = ""


class AssessRequest(BaseModel):
    findings: List[FindingIn] = []
    # customer priorities for the discretionary tier: {objective: high|medium|low}.
    # objectives: access | data | network_api | supply_updates | monitoring.
    weights: Optional[Dict[str, str]] = None
    # CE-risk-assessment safety functions for the cyber-meets-safety bridge.
    safety_functions: Optional[List[SafetyFunctionIn]] = None
    # hardware path: networked components -> derived cyber findings (no repo).
    components: Optional[List[ComponentIn]] = None


def _payload(body: AssessRequest) -> dict:
    findings = [f.model_dump() for f in body.findings]
    if body.components:
        findings = findings + findings_from_components([c.model_dump() for c in body.components])
    return {
        "findings": findings,
        "weights": body.weights,
        "safety_functions": [s.model_dump() for s in body.safety_functions] if body.safety_functions else None,
    }


def _assess_enriched(body: AssessRequest) -> dict:
    """Assessment + the network_security regulatory breadth (atom-grain).

    Breadth is attached at this view layer (db here), never in the pure mapper.
    """
    result = assess_findings_payload(_payload(body))
    db = SessionLocal()
    try:
        enrich_findings_with_breadth(result.get("mapped", []), db)
    finally:
        db.close()
    return result


@router.post("/assess")
async def assess(body: AssessRequest):
    return _assess_enriched(body)


@router.post("/projects/{project_id}/assess-snapshot")
async def assess_snapshot(project_id: str, body: AssessRequest, tenant_id: str = Depends(get_tenant_id)):
    """Run the assessment and persist it as a versioned snapshot (running system)."""
    assessment = _assess_enriched(body)
    snap = save_snapshot(project_id, tenant_id, assessment)
    return {"snapshot": snap, "assessment": assessment}


@router.get("/projects/{project_id}/assess-snapshots")
async def list_assess_snapshots(project_id: str, tenant_id: str = Depends(get_tenant_id)):
    return {"snapshots": list_snapshots(project_id, tenant_id)}


@router.get("/assess-snapshots/{snapshot_id}")
async def get_assess_snapshot(snapshot_id: str, tenant_id: str = Depends(get_tenant_id)):
    snap = get_snapshot(snapshot_id, tenant_id)
    if not snap:
        raise HTTPException(status_code=404, detail="Snapshot not found")
    return snap


# --- Lead-magnet readiness check (stateless, no project, no DB) ---

class ReadinessRequest(BaseModel):
    intended_use: Optional[str] = ""
    connected_to_internet: Optional[bool] = False
    has_software_updates: Optional[bool] = False
    processes_personal_data: Optional[bool] = False
    is_critical_infra_supplier: Optional[bool] = False
    has_firmware: Optional[bool] = False
    remote_maintenance: Optional[bool] = False        # implies connectivity + updates
    user_parameter_app: Optional[bool] = False        # implies connectivity + updates
    is_machinery: Optional[bool] = False              # CE machinery -> also Machinery Reg 2023/1230


# CRA Annex I evidence_type -> guideline bucket (Code / Prozess / Dokumentation).
_GUIDELINE_BUCKET = {"code": "code", "hybrid": "code", "process": "process", "document": "document"}
_PATH_HINT = {
    "CRITICAL": "Konformitaet ueber benannte Stelle / EUCC (Modul H/C)",
    "IMPORTANT_II": "Modul B+C oder harmonisierte Norm",
    "IMPORTANT_I": "Self-Assessment bei harmonisierten Normen, sonst Modul B",
    "STANDARD": "Self-Assessment (Modul A)",
    "NOT_IN_SCOPE": "—",
}

# Machinery Regulation 2023/1230 cyber-with-safety obligations come from the shared
# Controls-API (use_case=maschinen, atom-grain, license-clean) — NOT hardcoded.
# Cyber-relevant sub-topics -> guideline bucket.
_MACHINERY_SUBTOPICS = [
    ("sicherheitsanforderungen", "code"),
    ("risikomanagement", "process"),
    ("konformitaetsbewertung", "document"),
]


def _machinery_obligations(limit_per: int = 4) -> list:
    """(bucket, guideline_item) tuples from use_case=maschinen. Best-effort."""
    out = []
    db = SessionLocal()
    try:
        svc = UseCaseControlsService(db)
        for sub_topic, bucket in _MACHINERY_SUBTOPICS:
            try:
                res = svc.controls_for_use_case("maschinen", sub_topic=sub_topic, limit=limit_per)
            except Exception:
                continue
            for c in res.get("controls", []):
                out.append((bucket, {
                    "req_id": c.get("control_id"), "title": c.get("title"), "category": sub_topic,
                    "annex_anchor": c.get("source_regulation", "Maschinenverordnung (EU) 2023/1230"),
                    "severity": (c.get("severity") or "").upper(), "effort_days": None,
                    "measures": [], "source": "Maschinen-VO",
                }))
    finally:
        db.close()
    return out


@router.post("/readiness")
async def readiness(body: ReadinessRequest):
    """Low-friction CRA readiness check: business-scope answers -> Annex III/IV
    classification + a high-level guideline grouped Code / Prozess / Dokumentation.
    Reuses the deterministic classifier + Annex I spine. No project, no DB."""
    intake = {
        "intended_use": body.intended_use,
        "connected_to_internet": bool(body.connected_to_internet or body.remote_maintenance or body.user_parameter_app),
        "has_software_updates": bool(body.has_software_updates or body.remote_maintenance or body.user_parameter_app),
        "processes_personal_data": bool(body.processes_personal_data),
        "is_critical_infra_supplier": bool(body.is_critical_infra_supplier),
    }
    classification, rationale = _classify(intake)
    in_scope = classification != "NOT_IN_SCOPE"
    groups = {"code": [], "process": [], "document": []}
    regulations = []
    if in_scope:
        regulations.append("CRA")
        for req in ANNEX_I_REQUIREMENTS:
            bucket = _GUIDELINE_BUCKET.get(req.get("evidence_type", "process"), "process")
            groups[bucket].append({
                "req_id": req["req_id"], "title": req["title"], "category": req["category"],
                "annex_anchor": req["annex_anchor"], "severity": req["severity"],
                "effort_days": req.get("effort_days"),
                "measures": [{"id": m, "name": MEASURES.get(m, m)} for m in req.get("mapped_measures", [])],
                "source": "CRA",
            })
        # Machine/plant builders are ALSO hit by the new Machinery Regulation's
        # cyber-with-safety essential requirements (Annex III) — show the combination.
        if body.is_machinery:
            machinery = _machinery_obligations()
            if machinery:
                regulations.append("Maschinen-VO 2023/1230")
                for bucket, item in machinery:
                    groups[bucket].append(item)
    total_effort = sum(r["effort_days"] for g in groups.values() for r in g if r.get("effort_days"))
    return {
        "in_scope": in_scope,
        "classification": classification,
        "rationale": rationale,
        "conformity_path_hint": _PATH_HINT.get(classification, ""),
        "regulations": regulations,
        "guideline": groups,
        "counts": {k: len(v) for k, v in groups.items()},
        "total_effort_days": total_effort,
        "deadlines": list(DEADLINES),
    }