import { readFileSync, readdirSync } from "node:fs";
import { join } from "node:path";
import type { PrismaClient } from "@prisma/client";

/**
 * Importer für das VDA-ISA-2027-Vorlagenpaket (§6 der Spezifikation).
 * Liest die echten .md-Dateien, mapping.json, variables.schema.json,
 * Technische-Sicherheits-Baseline.md und Nachweisregister_zentral.md in die
 * Policy-Tabellen. Idempotent pro Mandant (löscht + legt neu an).
 */

type DocType = "LEITLINIE" | "RICHTLINIE" | "VERFAHREN" | "REGISTER";

function docCodeFromFile(file: string): string {
  return file.split("_")[0]; // "R08_…​.md" → "R08", "VA-03_…​.md" → "VA-03"
}
function titleOf(md: string): string {
  const m = md.match(/^#\s+(.+?)\s*$/m);
  return m ? m[1].trim() : "(ohne Titel)";
}
/** Umsetzungstext je Anforderung aus den `<!-- IMPL id -->`-Ankern extrahieren. */
function extractImpls(raw: string, into: Map<string, string>) {
  const lines = raw.split("\n");
  for (let i = 0; i < lines.length; i++) {
    const m = lines[i].match(/^<!--\s*IMPL\s+(\S+)\s*-->/);
    if (!m) continue;
    const buf: string[] = [];
    for (let j = i + 1; j < lines.length; j++) {
      const l = lines[j];
      const tr = l.trim();
      if (tr === "" || tr.startsWith("<!--") || tr.startsWith("{{#") || tr.startsWith("{{/") || /^#{1,6}\s/.test(tr) || tr.startsWith("**") || tr.startsWith("- ") || tr.startsWith("|")) break;
      buf.push(l);
    }
    if (buf.length) into.set(m[1], buf.join(" ").trim());
  }
}

function varGroup(key: string): string {
  if (key.startsWith("FLAG_")) return "Feature-Flags";
  if (key.startsWith("ORG_") || key.startsWith("ISMS_")) return "Organisation";
  if (key.startsWith("ROLE_")) return "Rollen";
  if (key.startsWith("DOC_")) return "Metadaten";
  if (key.startsWith("TECH_") || key.startsWith("TOOL_")) return "Technik/Werkzeuge";
  if (/^(PW_|MFA_|SESSION_|ACCOUNT_|RECERT_)/.test(key)) return "IAM-Baseline";
  if (key.startsWith("TLS_") || key.startsWith("CRYPTO_")) return "Krypto-Baseline";
  if (/^(PATCH_|VULN_|MALWARE_|LOG_|BACKUP_|PENTEST_)/.test(key)) return "Betriebs-Baseline";
  return "Sonstige";
}

interface SchemaProp {
  type?: string;
  title?: string;
  default?: string | boolean;
  example?: string;
}

export async function importPolicies(prisma: PrismaClient, tenantId: string, seedDir: string) {
  // Sauberer Neuimport pro Mandant
  await prisma.policyRequirement.deleteMany({ where: { tenantId } });
  await prisma.policyDocument.deleteMany({ where: { tenantId } });
  await prisma.policyVariable.deleteMany({ where: { tenantId } });
  await prisma.policyBaselineParam.deleteMany({ where: { tenantId } });
  await prisma.policyEvidence.deleteMany({ where: { tenantId } });

  // ── 1. mapping.json → FULFILLS-Rückwärtsmapping vorbereiten ──────────────
  const mapping = JSON.parse(readFileSync(join(seedDir, "mapping.json"), "utf-8")) as {
    anforderungen: Array<{
      id: string; policy: string; control: string; type: string;
      condition: string | null; requirement: string; implementation?: string; nachweis_link?: string;
    }>;
  };

  // ── 2. Dokumente einlesen (Richtlinien + Verfahren) ──────────────────────
  const reqToVas = new Map<string, Set<string>>();
  const implMap = new Map<string, string>(); // Umsetzungstext je Anforderung aus den IMPL-Ankern
  const docs: Array<{ code: string; type: DocType; title: string; policyCode: string | null; fulfills: string[]; raw: string; orderIdx: number }> = [];

  const richtDir = join(seedDir, "richtlinien");
  for (const file of readdirSync(richtDir).filter((f) => f.endsWith(".md")).sort()) {
    const raw = readFileSync(join(richtDir, file), "utf-8");
    const code = docCodeFromFile(file);
    const type: DocType = code === "L00" ? "LEITLINIE" : "RICHTLINIE";
    const orderIdx = code === "L00" ? 0 : parseInt(code.replace(/\D/g, ""), 10);
    extractImpls(raw, implMap);
    docs.push({ code, type, title: titleOf(raw), policyCode: null, fulfills: [], raw, orderIdx });
  }

  const verfDir = join(seedDir, "verfahren");
  for (const file of readdirSync(verfDir).filter((f) => f.endsWith(".md")).sort()) {
    const raw = readFileSync(join(verfDir, file), "utf-8");
    const code = docCodeFromFile(file);
    const fh = raw.match(/<!--\s*FULFILLS\s+([^|]+?)\s*\|\s*POLICY\s+(\S+)\s*-->/);
    const fulfills = fh ? fh[1].split(",").map((s) => s.trim()).filter(Boolean) : [];
    const policyCode = fh ? fh[2].trim() : null;
    for (const req of fulfills) {
      if (!reqToVas.has(req)) reqToVas.set(req, new Set());
      reqToVas.get(req)!.add(code);
    }
    const orderIdx = 100 + parseInt(code.replace(/\D/g, ""), 10);
    docs.push({ code, type: "VERFAHREN", title: titleOf(raw), policyCode, fulfills, raw, orderIdx });
  }

  // Register-Dokumente (Baseline + Nachweisregister) mitführen
  const baselineRaw = readFileSync(join(seedDir, "Technische-Sicherheits-Baseline.md"), "utf-8");
  const nachweisRaw = readFileSync(join(seedDir, "Nachweisregister_zentral.md"), "utf-8");
  docs.push({ code: "BASELINE", type: "REGISTER", title: titleOf(baselineRaw), policyCode: null, fulfills: [], raw: baselineRaw, orderIdx: 900 });
  docs.push({ code: "NACHWEIS", type: "REGISTER", title: titleOf(nachweisRaw), policyCode: null, fulfills: [], raw: nachweisRaw, orderIdx: 901 });

  for (const d of docs) {
    await prisma.policyDocument.create({
      data: {
        tenantId, code: d.code, type: d.type, title: d.title, version: "1.0", status: "FREIGEGEBEN",
        policyCode: d.policyCode, fulfills: d.fulfills, rawMarkdown: d.raw, orderIdx: d.orderIdx,
      },
    });
  }

  // ── 3. Anforderungen (mapping.json) + vaCodes ────────────────────────────
  for (const a of mapping.anforderungen) {
    await prisma.policyRequirement.create({
      data: {
        tenantId, reqId: a.id, policyCode: a.policy, control: a.control, obligation: a.type,
        condition: a.condition, requirement: a.requirement, implementation: implMap.get(a.id) ?? a.implementation ?? "",
        vaCodes: [...(reqToVas.get(a.id) ?? [])].sort(), nachweisLink: a.nachweis_link ?? null,
      },
    });
  }

  // ── 4. Variablen + Feature-Flags (variables.schema.json) ─────────────────
  const schema = JSON.parse(readFileSync(join(seedDir, "variables.schema.json"), "utf-8")) as {
    properties: Record<string, SchemaProp>; required?: string[];
  };
  const required = new Set(schema.required ?? []);
  let vi = 0;
  for (const [key, prop] of Object.entries(schema.properties)) {
    const kind = prop.type === "boolean" ? "boolean" : "string";
    const value = prop.default !== undefined ? String(prop.default) : prop.example !== undefined ? String(prop.example) : kind === "boolean" ? "false" : "";
    await prisma.policyVariable.create({
      data: { tenantId, key, title: prop.title ?? key, kind, groupName: varGroup(key), value, required: required.has(key), orderIdx: vi++ },
    });
  }

  // ── 5. Baseline-Parameter (Technische-Sicherheits-Baseline.md) ───────────
  let section = "";
  let bi = 0;
  for (const line of baselineRaw.split("\n")) {
    const h = line.match(/^##\s+(.+?)\s*$/);
    if (h) { section = h[1].trim(); continue; }
    const row = line.match(/^\|\s*(BL-[A-Z]+-\d+)\s*\|\s*(.+?)\s*\|\s*(.+?)\s*\|\s*$/);
    if (row) {
      await prisma.policyBaselineParam.create({
        data: { tenantId, blId: row[1], section, name: row[2].trim(), vorgabe: row[3].trim(), orderIdx: bi++ },
      });
    }
  }

  // ── 6. Nachweisregister (Nachweisregister_zentral.md) ────────────────────
  for (const line of nachweisRaw.split("\n")) {
    const row = line.match(/^\|\s*(\d+)\s*\|\s*(.+?)\s*\|\s*(.+?)\s*\|\s*(.+?)\s*\|\s*(.+?)\s*\|\s*(.+?)\s*\|\s*$/);
    if (!row) continue;
    const policyMatch = row[2].match(/\{\{LINK:([^}]+)\}\}/);
    await prisma.policyEvidence.create({
      data: {
        tenantId, nr: parseInt(row[1], 10), policyCode: policyMatch ? policyMatch[1] : row[2].trim(),
        nachweis: row[3].trim(), quelle: row[4].trim(), verantwortlich: row[5].trim(), turnus: row[6].trim(),
      },
    });
  }

  const counts = {
    documents: docs.length,
    requirements: mapping.anforderungen.length,
    variables: Object.keys(schema.properties).length,
    baseline: bi,
  };
  return counts;
}