import fs from 'node:fs';
import path from 'node:path';
import { normalizePageAccessPolicy } from './page-access-policy.mjs';

export function resolvePageDataPolicyDir(workspaceRoot) {
  return path.join(workspaceRoot, '.mindspace', 'page-data-policies');
}

export function resolvePageDataPolicyPath(workspaceRoot, pageId) {
  const safePageId = String(pageId ?? '').trim();
  if (!safePageId || /[\\/]/.test(safePageId)) {
    throw Object.assign(new Error('pageId 无效'), { code: 'invalid_page_id' });
  }
  return path.join(resolvePageDataPolicyDir(workspaceRoot), `${safePageId}.json`);
}

export function readPageAccessPolicy(workspaceRoot, pageId) {
  const policyPath = resolvePageDataPolicyPath(workspaceRoot, pageId);
  if (!fs.existsSync(policyPath)) return null;
  const raw = JSON.parse(fs.readFileSync(policyPath, 'utf8'));
  return normalizePageAccessPolicy(raw, { fallbackPageId: pageId });
}

export function writePageAccessPolicy(workspaceRoot, policyInput) {
  const policy = normalizePageAccessPolicy(policyInput);
  const policyDir = resolvePageDataPolicyDir(workspaceRoot);
  fs.mkdirSync(policyDir, { recursive: true });
  const policyPath = resolvePageDataPolicyPath(workspaceRoot, policy.pageId);
  fs.writeFileSync(
    policyPath,
    `${JSON.stringify({ ...policy, updatedAt: new Date().toISOString() }, null, 2)}\n`,
    'utf8',
  );
  return readPageAccessPolicy(workspaceRoot, policy.pageId);
}

export function deletePageAccessPolicy(workspaceRoot, pageId) {
  const policyPath = resolvePageDataPolicyPath(workspaceRoot, pageId);
  if (!fs.existsSync(policyPath)) return false;
  fs.unlinkSync(policyPath);
  return true;
}

export function listPageAccessPolicies(workspaceRoot) {
  const policyDir = resolvePageDataPolicyDir(workspaceRoot);
  if (!fs.existsSync(policyDir)) return [];
  return fs
    .readdirSync(policyDir)
    .filter((name) => name.endsWith('.json'))
    .map((name) => readPageAccessPolicy(workspaceRoot, name.replace(/\.json$/, '')))
    .filter(Boolean);
}