const crypto = require('node:crypto');

class EncryptionHelper {
    static encryptDataAESGCM(plainText, key) {
        try {
            const iv = crypto.randomBytes(12);
            const cipher = crypto.createCipheriv('aes-256-gcm', key, iv);

            const encryptedText = Buffer.concat([cipher.update(plainText, 'utf8'), cipher.final()]);
            const authTag = cipher.getAuthTag();

            return Buffer.concat([iv, encryptedText, authTag]);
        } catch (error) {
            console.error("Encryption failed:", error);
            return null;
        }
    }

    static makeEncryptedParameter(username, key) {
        const timestamp = new Date().toISOString().replace('T', ' ').split('.')[0];
        const plainText = `${timestamp} ${username}`;

        const hash = crypto.createHash('sha256').update(key, 'utf8').digest();
        const encryptedData = this.encryptDataAESGCM(plainText, hash);

        const base64Encoded = encryptedData.toString('base64');

        return base64Encoded;
    }
}

module.exports = EncryptionHelper