import { Keypair, VersionedTransaction } from '@solana/web3.js'
import bs58 from 'bs58'
import { PrepareTransactionExtended } from '@heliofi/common'

class WalletService {
  private getPrivateKey(): string {
    // The base58 encoded private key.
    const privateKey = import.meta.env.VITE_WALLET_PRIVATE_KEY
    if (!privateKey) {
      throw new Error('Wallet private key not configured.')
    }
    return privateKey
  }

  createWallet() {
    try {
      const privateKey = this.getPrivateKey()
      // The Keypair object built from the private key.
      return Keypair.fromSecretKey(bs58.decode(privateKey))
    } catch (error) {
      console.error('Error creating wallet:', error)
      throw error
    }
  }

  async signTransaction(
    preparedTransaction: PrepareTransactionExtended,
  ): Promise<string> {
    try {
      const wallet = this.createWallet()
      // The serialized transaction from the prepared transaction (The response from the prepare endpoint).
      const { serializedTransaction } = preparedTransaction

      // Create a VersionedTransaction object from the serialized transaction.
      const vtx = VersionedTransaction.deserialize(
        Buffer.from(serializedTransaction!, 'base64'),
      )

      // Sign the transaction with the wallet.
      vtx.sign([wallet])

      // Serialize the signed transaction and return it as a base64 string.
      const signedAsBufferJson = Buffer.from(vtx.serialize()).toString('base64')

      return signedAsBufferJson
    } catch (error) {
      console.error('Error signing transaction:', error)
      throw new Error(
        `Failed to sign transaction: ${error instanceof Error ? error.message : 'Unknown error'}`,
      )
    }
  }

  getWalletAddress(): string {
    try {
      const wallet = this.createWallet()
      return wallet.publicKey.toBase58()
    } catch (error) {
      console.error('Error getting wallet address:', error)
      throw error
    }
  }
}

export const walletService = new WalletService()