import crypto from 'node:crypto';

export function buildPageDataPolicyScopeHash(policy) {
  const payload = {
    accessMode: policy?.accessMode ?? null,
    datasets: Object.keys(policy?.datasets ?? {}).sort(),
  };
  return crypto.createHash('sha256').update(JSON.stringify(payload)).digest('hex').slice(0, 16);
}

export async function upsertPageDataPolicyIndex(pool, policy) {
  if (!pool || !policy?.pageId || !policy?.ownerUserId) return null;
  const datasetCount = Object.keys(policy.datasets ?? {}).length;
  const now = Date.now();
  await pool.query(
    `INSERT INTO h5_page_data_policy_index
      (page_id, owner_user_id, access_mode, dataset_count, scope_hash, updated_at)
     VALUES (?, ?, ?, ?, ?, ?)
     ON DUPLICATE KEY UPDATE
      owner_user_id = VALUES(owner_user_id),
      access_mode = VALUES(access_mode),
      dataset_count = VALUES(dataset_count),
      scope_hash = VALUES(scope_hash),
      updated_at = VALUES(updated_at)`,
    [
      policy.pageId,
      policy.ownerUserId,
      policy.accessMode,
      datasetCount,
      buildPageDataPolicyScopeHash(policy),
      now,
    ],
  );
  return {
    pageId: policy.pageId,
    ownerUserId: policy.ownerUserId,
    accessMode: policy.accessMode,
    datasetCount,
    scopeHash: buildPageDataPolicyScopeHash(policy),
    updatedAt: now,
  };
}

export async function getPageDataPolicyIndex(pool, pageId) {
  if (!pool) return null;
  const [rows] = await pool.query(
    `SELECT page_id, owner_user_id, access_mode, dataset_count, scope_hash, updated_at
     FROM h5_page_data_policy_index
     WHERE page_id = ?
     LIMIT 1`,
    [pageId],
  );
  const row = rows[0];
  if (!row) return null;
  return {
    pageId: row.page_id,
    ownerUserId: row.owner_user_id,
    accessMode: row.access_mode,
    datasetCount: Number(row.dataset_count ?? 0),
    scopeHash: row.scope_hash,
    updatedAt: Number(row.updated_at ?? 0),
  };
}

export async function listPageDataPolicyIndexByOwner(pool, ownerUserId, { limit = 50 } = {}) {
  if (!pool) return [];
  const safeLimit = Math.min(Math.max(1, Number(limit ?? 50)), 200);
  const [rows] = await pool.query(
    `SELECT page_id, owner_user_id, access_mode, dataset_count, scope_hash, updated_at
     FROM h5_page_data_policy_index
     WHERE owner_user_id = ?
     ORDER BY updated_at DESC
     LIMIT ?`,
    [ownerUserId, safeLimit],
  );
  return rows.map((row) => ({
    pageId: row.page_id,
    ownerUserId: row.owner_user_id,
    accessMode: row.access_mode,
    datasetCount: Number(row.dataset_count ?? 0),
    scopeHash: row.scope_hash,
    updatedAt: Number(row.updated_at ?? 0),
  }));
}

export async function deletePageDataPolicyIndex(pool, pageId) {
  if (!pool || !pageId) return false;
  const [result] = await pool.query(`DELETE FROM h5_page_data_policy_index WHERE page_id = ?`, [pageId]);
  return Number(result?.affectedRows ?? 0) > 0;
}