import { type NextRequest, NextResponse } from 'next/server';

import { isAuthorized, unauthorized } from './auth';
import { getServerLocaleMap } from './localeServer';
import { matchKeys } from './localization';

type RouteContext = { params: Promise<Record<string, string>> };
type Handler = (req: NextRequest, ctx: RouteContext) => Promise<NextResponse>;

/**
 * Wraps a route handler with auth checking and unified error handling.
 *
 * @example
 * export const GET = withAuth(async (req) => {
 *   const rows = await pool.query('...');
 *   return NextResponse.json(rows);
 * });
 */
export function withAuth(handler: Handler): Handler {
  return async (req, ctx) => {
    if (!isAuthorized(req)) return unauthorized();
    try {
      return await handler(req, ctx);
    } catch (err) {
      console.error(err);
      return NextResponse.json({ error: 'Internal server error' }, { status: 500 });
    }
  };
}

/**
 * Builds a SQL WHERE clause fragment for item whitelist/blacklist filtering.
 *
 * - `isWhitelist=true`:  `item_key ~* $N OR item_key = ANY($N+1)`  (regex),  `item_key = ANY($N)`  (exact)
 * - `isWhitelist=false`: `item_key !~* $N AND item_key != ALL($N+1)` (regex), `item_key != ALL($N)` (exact)
 *
 * Mutates `values` and `param.current` to track parameter bindings.
 */
export function buildItemFilter(
  items: string[],
  useRegex: boolean,
  isWhitelist: boolean,
  values: unknown[],
  param: { current: number },
): string | null {
  if (items.length === 0) return null;

  if (useRegex) {
    const localeMap = getServerLocaleMap();
    const localeKeys = [...new Set(items.flatMap((p) => matchKeys(p, localeMap)))];
    const sqlPattern = items.map((p) => `(${p})`).join('|');

    if (isWhitelist) {
      const orConds: string[] = [`item_key ~* $${param.current++}`];
      values.push(sqlPattern);
      if (localeKeys.length > 0) {
        orConds.push(`item_key = ANY($${param.current++})`);
        values.push(localeKeys);
      }
      return `(${orConds.join(' OR ')})`;
    } else {
      const andConds: string[] = [`item_key !~* $${param.current++}`];
      values.push(sqlPattern);
      if (localeKeys.length > 0) {
        andConds.push(`item_key != ALL($${param.current++})`);
        values.push(localeKeys);
      }
      return `(${andConds.join(' AND ')})`;
    }
  }

  if (isWhitelist) {
    values.push(items);
    return `item_key = ANY($${param.current++})`;
  } else {
    values.push(items);
    return `item_key != ALL($${param.current++})`;
  }
}