import type { NextRequest } from "next/server";
import {
  LEGACY_NEWAPIWG_API_KEY_HEADER,
  NEWAPIWG_API_KEY_HEADER,
} from "@/utils/gatewayHeaders";
import { ApiError } from "./_errors";

export interface LoginContext {
  token: string;
}

export function getRequestToken(request: Request | NextRequest): string | null {
  const tokenHeader = request.headers.get("token");
  if (tokenHeader?.trim()) return tokenHeader.trim();

  const userTokenHeader = request.headers.get("X-User-Token");
  if (userTokenHeader?.trim()) return userTokenHeader.trim();

  const userAuthorization = request.headers.get("X-User-Authorization");
  const userBearerToken = userAuthorization?.match(/^Bearer\s+(.+)$/i)?.[1];
  if (userBearerToken?.trim()) return userBearerToken.trim();

  const authorization = request.headers.get("authorization");
  const bearerToken = authorization?.match(/^Bearer\s+(.+)$/i)?.[1];
  return bearerToken?.trim() || null;
}

export function getRequestGatewayApiKey(request: Request | NextRequest): string | null {
  return (
    request.headers.get(NEWAPIWG_API_KEY_HEADER)?.trim() ||
    request.headers.get(LEGACY_NEWAPIWG_API_KEY_HEADER)?.trim() ||
    null
  );
}

export function requireLogin(request: Request | NextRequest): LoginContext {
  const token = getRequestToken(request);
  if (!token) {
    throw ApiError.unauthorized();
  }
  return { token };
}

export function buildUserForwardHeaders(token?: string | null): Record<string, string> {
  if (!token?.trim()) return {};
  const normalizedToken = token.trim();
  return {
    "X-User-Authorization": `Bearer ${normalizedToken}`,
    "X-User-Token": normalizedToken,
    token: normalizedToken,
  };
}

export function buildGatewayHeaders(
  apiKey: string,
  loginToken?: string | null,
  extraHeaders?: Record<string, string>
): Record<string, string> {
  return {
    ...(extraHeaders || {}),
    Authorization: `Bearer ${apiKey}`,
    ...buildUserForwardHeaders(loginToken),
  };
}

export function requireConfiguredValue(
  value: string | null | undefined,
  message: string,
  status = 401
): string {
  if (!value) {
    throw ApiError.config(message, status);
  }
  return value;
}