package main

import (
	"errors"
	"fmt"
	"io/ioutil"
	"time"

	"github.com/ethereum/go-ethereum/accounts"
	"github.com/ethereum/go-ethereum/cmd/utils"
	"github.com/ethereum/go-ethereum/common"
	"github.com/ethereum/go-ethereum/eth"
	"github.com/ethereum/go-ethereum/les"
	"github.com/ethereum/go-ethereum/logger"
	"github.com/ethereum/go-ethereum/logger/glog"
	"github.com/ethereum/go-ethereum/crypto"
	errextra "github.com/pkg/errors"
)

var (
	scryptN = 4096
	scryptP = 6
)

// createAccount creates an internal geth account
func createAccount(password string) (string, string, error) {

	if currentNode != nil {

		w := true

		// Retrieve the AccountManager
		var ethereum *eth.FullNodeService
		var accountManager *accounts.Manager
		if err := currentNode.Service(&ethereum); err == nil {
			accountManager = ethereum.ApiBackend.AccountManager()
		} else {
			var ethereum *les.LightNodeService
			if err := currentNode.Service(&ethereum); err == nil {
				accountManager = ethereum.ApiBackend.AccountManager()
			} else {
				glog.V(logger.Warn).Infoln("cannot get account manager:", err)
			}
		}

		if accountManager != nil {
			// generate the account
			account, err := accountManager.NewAccount(password, w)
			if err != nil {
				return "", "", errextra.Wrap(err, "Account manager could not create the account")
			}
			address := fmt.Sprintf("%x", account.Address)

			// recover the public key to return
			keyContents, err := ioutil.ReadFile(account.File)
			if err != nil {
				return address, "", errextra.Wrap(err, "Could not load the key contents")
			}
			key, err := accounts.DecryptKey(keyContents, password)
			if err != nil {
				return address, "", errextra.Wrap(err, "Could not recover the key")
			}
			pubKey := common.ToHex(crypto.FromECDSAPub(&key.PrivateKey.PublicKey))

			return address, pubKey, nil
		}
		return "", "", errors.New("Could not retrieve account manager")

	}

	return "", "", errors.New("No running node detected for account creation")

}

// unlockAccount unlocks an existing account for a certain duration and
// inject the account as a whisper identity if the account was created as
// a whisper enabled account
func unlockAccount(address, password string, seconds int) error {

	if currentNode != nil {

		// Retrieve the AccountManager
		var ethereum *eth.FullNodeService
		var accountManager *accounts.Manager
		if err := currentNode.Service(&ethereum); err == nil {
			accountManager = ethereum.ApiBackend.AccountManager()
		} else {
			var ethereum *les.LightNodeService
			if err := currentNode.Service(&ethereum); err == nil {
				accountManager = ethereum.ApiBackend.AccountManager()
			} else {
				glog.V(logger.Warn).Infoln("cannot get account manager:", err)
			}
		}

		if accountManager != nil {
			account, err := utils.MakeAddress(accountManager, address)
			if err != nil {
				return errextra.Wrap(err, "Could not retrieve account from address")
			}

			err = accountManager.TimedUnlock(account, password, time.Duration(seconds)*time.Second)
			if err != nil {
				return errextra.Wrap(err, "Could not decrypt account")
			}
			return nil
		}
		return errors.New("Could not retrieve account manager")
	}

	return errors.New("No running node detected for account unlock")

}

// createAndStartNode creates a node entity and starts the
// node running locally
func createAndStartNode(inputDir string) error {

	currentNode = MakeNode(inputDir)
	if currentNode != nil {
		RunNode(currentNode)
		return nil
	}

	return errors.New("Could not create the in-memory node object")

}