import { NextResponse } from "next/server";
import { cookies } from "next/headers";
import { randomUUID } from "crypto";
import { formatPhoneDisplay } from "@/app/features/UserRoles/utils";

const BE_BASE_URL = process.env.BE_BASE_URL || "http://localhost:8583";
const COOKIE_NAME = "auth_token";

// Interface matching the backend RegisterRequest
interface RegisterRequest {
  creator: string;
  email: string;
  first_name: string;
  groups: string[];
  job_title: string;
  last_name: string;
  merchants: string[];
  phone: string;
  username: string;
}

// Frontend form interface
interface FrontendRegisterForm {
  email: string;
  firstName: string;
  lastName: string;
  username: string;
  phone?: string;
  jobTitle?: string;
  groups?: string[];
  merchants?: string[];
  creator?: string;
}

export async function POST(request: Request) {
  try {
    const body: FrontendRegisterForm = await request.json();

    // Get the auth token from cookies
    const cookieStore = await cookies();
    const token = cookieStore.get(COOKIE_NAME)?.value;

    if (!token) {
      return NextResponse.json(
        {
          success: false,
          message: "No authentication token found",
        },
        { status: 401 }
      );
    }

    // Validate required fields
    const requiredFields = ["email", "firstName", "lastName", "username"];
    const missingFields = requiredFields.filter(
      field => !body[field as keyof FrontendRegisterForm]
    );

    if (missingFields.length > 0) {
      return NextResponse.json(
        {
          success: false,
          message: `Missing required fields: ${missingFields.join(", ")}`,
        },
        { status: 400 }
      );
    }

    // Map frontend payload to backend RegisterRequest format
    const registerPayload: RegisterRequest = {
      creator: body.creator || randomUUID(), // Generate UUID if not provided
      email: body.email,
      first_name: body.firstName,
      groups: body.groups || ["Reader"], // Default to empty array if not provided
      job_title: body.jobTitle || "Reader",
      last_name: body.lastName,
      merchants: body.merchants || ["Win Bot"], // Default to empty array if not provided
      phone: body.phone ? formatPhoneDisplay(body.phone, body.countryCode) : "",
      username: body.username,
    };

    // Call backend registration endpoint
    const resp = await fetch(`${BE_BASE_URL}/api/v1/auth/register`, {
      method: "POST",
      headers: {
        "Content-Type": "application/json",
        Authorization: `Bearer ${token}`,
      },
      body: JSON.stringify(registerPayload),
    });

    console.log("[DEBUG] [REGISTER-PAYLOAD]: ", registerPayload);

    // Handle backend response
    if (!resp.ok) {
      const errorData = await safeJson(resp);
      console.log("[DEBUG] [REGISTER-ERROR]: ", errorData);
      return NextResponse.json(
        {
          success: false,
          message: errorData?.message || "Registration failed",
        },
        { status: resp.status }
      );
    }

    const data = await resp.json();

    console.log("[DEBUG] [REGISTER]: ", data);

    return NextResponse.json(
      {
        success: true,
        message: "Registration successful",
        user: data.user || null,
      },
      { status: 201 }
    );
  } catch (error) {
    console.error("Registration proxy error:", error);
    return NextResponse.json(
      {
        success: false,
        message: "Internal server error during registration",
      },
      { status: 500 }
    );
  }
}

// Helper function to safely parse JSON responses
async function safeJson(resp: Response) {
  try {
    return await resp.json();
  } catch {
    return null;
  }
}