package utils

import (
	"crypto/rand"
	"crypto/rsa"
	"crypto/sha256"
	"crypto/x509"
	"encoding/hex"
)

func GenerateKeyID(publicKey *rsa.PublicKey) (string, error) {
	pubKeyBytes, err := x509.MarshalPKIXPublicKey(publicKey)
	if err != nil {
		return "", err
	}
	hash := sha256.Sum256(pubKeyBytes)
	return hex.EncodeToString(hash[:8]), nil
}

func GenerateClientID() (string, error) {
	bytes := make([]byte, 16)
	if _, err := rand.Read(bytes); err != nil {
		return "", err
	}
	return hex.EncodeToString(bytes), nil
}

func GenerateClientSecret() (string, error) {
	bytes := make([]byte, 32)
	if _, err := rand.Read(bytes); err != nil {
		return "", err
	}
	return hex.EncodeToString(bytes), nil
}

func GenerateState() (string, error) {
	bytes := make([]byte, 16)
	if _, err := rand.Read(bytes); err != nil {
		return "", err
	}
	return hex.EncodeToString(bytes), nil
}