import { NextResponse } from 'next/server';
import jwt from "jsonwebtoken";
import { createClient } from '@/utils/supabase/server';

const ALGORITHM = "HS256";

interface TokenPayload {
    [key: string]: any;
}

const createSupabaseToken = (
    jwtSecretKey: string,
    data: TokenPayload,
    // Set expiration to null for no expiration, or use a very large number like 10 years
    expireDays: number | null = 3650 // Default to 10 years
): string => {
    const toEncode = {
        aud: 'authenticated',
        role: 'authenticated',
        sub: data.user_id,
        email: data.email,
        // Only include exp if expireDays is not null
        ...(expireDays && {
            exp: Math.floor(Date.now() / 1000) + (expireDays * 86400)
        }),
        user_metadata: {
            ...data
        }
    };

    const encodedJwt = jwt.sign(toEncode, jwtSecretKey, {
        algorithm: ALGORITHM
    });
    return encodedJwt;
};

const getUserByMacAddress = async (macAddress: string) => {
    const supabase = createClient();
    const { data, error } = await supabase.from('devices').select('*, user:user_id(*)').eq('mac_address', macAddress).single();
    if (error) {
        throw new Error(error.message);
    }
    return data.user;
};

export async function GET(req: Request) {
    try {
        const { searchParams } = new URL(req.url);
        const macAddress = searchParams.get('macAddress');
        
        if (!macAddress) {
            return NextResponse.json(
                { error: 'MAC address is required' },
                { status: 400 }
            );
        }

        const user = await getUserByMacAddress(macAddress);

        if (!user) {
            return NextResponse.json(
                { error: 'User not found' },
                { status: 400 }
            );
        }

        const payload = {
            email: user.email,
            user_id: user.user_id,
            created_time: new Date()
        };

        const token = createSupabaseToken(process.env.JWT_SECRET_KEY!, payload, null);

        return NextResponse.json({ token });
    } catch (error) {
        return NextResponse.json(
            { error: error instanceof Error ? error.message : 'Internal server error' },
            { status: 500 }
        );
    }
}