import { Injectable } from '@nestjs/common';
import { GatiService } from '@nxtoai/gati';

@Injectable()
export class JwtHelper {
    
    private readonly TOKEN_PREFIX = 'token:';
    private readonly USER_TOKEN_PREFIX = 'user_token:';
    private readonly TOKEN_EXPIRY = 24 * 60 * 60; // 24 hours in seconds

    constructor(private readonly gati: GatiService) {}

    async cacheToken(token: string, userid: string): Promise<void> {
        await this.gati.put(`${this.TOKEN_PREFIX}${token}`, { value: userid }, { ttl: this.TOKEN_EXPIRY });
        await this.gati.put(`${this.USER_TOKEN_PREFIX}${userid}`, { value: token }, { ttl: this.TOKEN_EXPIRY });
    }

    async getTokenUser(token: string): Promise<string | null> {
        const cachedUser = await this.gati.get(`${this.TOKEN_PREFIX}${token}`);
        return cachedUser?.value && typeof cachedUser.value === 'string' ? cachedUser.value : null;
    }

    async getUserToken(userid: string): Promise<string | null> {
        const cachedToken = await this.gati.get(`${this.USER_TOKEN_PREFIX}${userid}`);
        return cachedToken?.value && typeof cachedToken.value === 'string' ? cachedToken.value : null;
    }

    async invalidateToken(token: string): Promise<void> {
        const userid = await this.getTokenUser(token);
        if (userid) {
            await this.gati.remove(`${this.USER_TOKEN_PREFIX}${userid}`);
        }
        await this.gati.remove(`${this.TOKEN_PREFIX}${token}`);
    }

    async invalidateUserToken(userid: string): Promise<void> {
        const token = await this.getUserToken(userid);
        if (token) {
            await this.gati.remove(`${this.TOKEN_PREFIX}${token}`);
        }
        await this.gati.remove(`${this.USER_TOKEN_PREFIX}${userid}`);
    }
}