const { normalizeVirtualPath } = require('./path-safety');

const SHARE_CODE_PATTERN = /^[A-Za-z0-9]{6,32}$/;

function isValidShareCode(code) {
  return typeof code === 'string' && SHARE_CODE_PATTERN.test(code);
}

function isPathWithinShare(requestPath, share) {
  if (!requestPath || !share) return false;

  const normalizedRequest = normalizeVirtualPath(requestPath);
  const normalizedShare = normalizeVirtualPath(share.share_path);
  if (!normalizedRequest || !normalizedShare) return false;

  if (share.share_type === 'file') return normalizedRequest === normalizedShare;

  const sharePrefix = normalizedShare.endsWith('/') ? normalizedShare : `${normalizedShare}/`;
  return normalizedRequest === normalizedShare || normalizedRequest.startsWith(sharePrefix);
}

function parseShareIpWhitelist(rawValue) {
  if (typeof rawValue !== 'string') return [];
  return rawValue
    .split(/[\s,;]+/)
    .map((item) => item.trim())
    .filter(Boolean)
    .slice(0, 100);
}

function isShareIpAllowed(clientIp, whitelist = []) {
  if (!Array.isArray(whitelist) || whitelist.length === 0) return true;
  if (!clientIp) return false;

  for (const rule of whitelist) {
    const normalizedRule = String(rule || '').trim();
    if (!normalizedRule) continue;
    if (normalizedRule === clientIp) return true;

    if (normalizedRule.endsWith('*')) {
      const prefix = normalizedRule.slice(0, -1);
      if (prefix && clientIp.startsWith(prefix)) return true;
    }
  }

  return false;
}

module.exports = {
  isPathWithinShare,
  isShareIpAllowed,
  isValidShareCode,
  parseShareIpWhitelist
};