package tools

import (
	"bytes"
	"crypto/ed25519"
	"crypto/x509"
	"encoding/pem"
	"fmt"
	"os"

	"cloud.o-forge.io/core/oc-lib/config"
	"github.com/libp2p/go-libp2p/core/crypto"
)

func LoadKeyFromFilePrivate() (crypto.PrivKey, error) {
	path := config.GetConfig().PrivateKeyPath
	data, err := os.ReadFile(path)
	if err != nil {
		return nil, err
	}

	block, _ := pem.Decode(data)
	if block == nil {
		return nil, fmt.Errorf("failed to decode PEM")
	}

	keyAny, err := x509.ParsePKCS8PrivateKey(block.Bytes)
	if err != nil {
		return nil, err
	}

	edKey, ok := keyAny.(ed25519.PrivateKey)
	if !ok {
		return nil, fmt.Errorf("not an ed25519 key")
	}

	// Convert properly to libp2p key
	privKey, _, err := crypto.GenerateEd25519Key(
		bytes.NewReader(edKey.Seed()),
	)
	if err != nil {
		return nil, err
	}

	return privKey, nil
}

func LoadKeyFromFilePublic() (crypto.PubKey, error) {
	path := config.GetConfig().PublicKeyPath

	data, err := os.ReadFile(path)
	if err != nil {
		return nil, err
	}

	block, _ := pem.Decode(data)
	if block == nil {
		return nil, fmt.Errorf("failed to decode PEM")
	}

	keyAny, err := x509.ParsePKIXPublicKey(block.Bytes)
	if err != nil {
		return nil, err
	}

	edKey, ok := keyAny.(ed25519.PublicKey)
	if !ok {
		return nil, fmt.Errorf("not an ed25519 key")
	}

	// Convert Go ed25519 key to libp2p key
	pubKey, err := crypto.UnmarshalEd25519PublicKey(edKey)
	if err != nil {
		return nil, err
	}

	return pubKey, nil
}