// Function to convert base64 to VersionedTransaction
import { getAllLookupTables, transformFromLookupTableAccounts } from './index';
import {
  Account,
  Address,
  CompiledTransactionMessage,
  decompileTransactionMessage,
  getCompiledTransactionMessageDecoder,
  getTransactionDecoder,
  Instruction,
  Rpc,
  SolanaRpcApi,
  Transaction,
} from '@solana/kit';
import { AddressLookupTable } from '@solana-program/address-lookup-table';
import { CompilableTransactionMessage } from '@solana/transaction-messages';

export function base64ToTransaction(base64Txn: string): Transaction {
  // Decode base64 into a Uint8Array
  const txnBuffer = Buffer.from(base64Txn, 'base64');
  // Deserialize the transaction
  return getTransactionDecoder().decode(txnBuffer);
}

export async function extractInstructionsAndLookupTablesFromTxn(
  connection: Rpc<SolanaRpcApi>,
  txn: Transaction,
): Promise<{
  instructions: Instruction[];
  lookupTables: Account<AddressLookupTable>[];
}> {
  const dMessage: CompiledTransactionMessage = getCompiledTransactionMessageDecoder().decode(txn.messageBytes);
  let lutAddresses: Address[] = [];
  if (dMessage.version !== 'legacy') {
    lutAddresses = dMessage.addressTableLookups?.map((lut) => lut.lookupTableAddress) ?? [];
  }

  let decompiled: CompilableTransactionMessage;
  let lutAccounts: Account<AddressLookupTable>[] = [];
  if (lutAddresses.length) {
    lutAccounts = await getAllLookupTables(connection, lutAddresses);
    const addresses = transformFromLookupTableAccounts(lutAccounts);
    decompiled = decompileTransactionMessage(dMessage, { addressesByLookupTableAddress: addresses });
  } else {
    decompiled = decompileTransactionMessage(dMessage);
  }

  const instructions: Instruction[] = decompiled.instructions.map((ix) => ({ ...ix }));

  return { instructions, lookupTables: lutAccounts };
}