import {
  PublicKey,
  SYSVAR_CLOCK_PUBKEY,
  SYSVAR_RENT_PUBKEY,
  TransactionInstruction,
} from '@solana/web3.js';

export let BPF_UPGRADE_LOADER_ID = new PublicKey(
  'BPFLoaderUpgradeab1e11111111111111111111111',
);
export async function createUpgradeInstruction(
  programId: PublicKey,
  bufferAddress: PublicKey,
  upgradeAuthority: PublicKey,
  spillAddress: PublicKey,
) {
  const bpfUpgradableLoaderId = BPF_UPGRADE_LOADER_ID;

  const [programDataAddress] = await PublicKey.findProgramAddress(
    [programId.toBuffer()],
    bpfUpgradableLoaderId,
  );

  const keys = [
    {
      pubkey: programDataAddress,
      isWritable: true,
      isSigner: false,
    },
    {
      pubkey: programId,
      isWritable: true,
      isSigner: false,
    },
    {
      pubkey: bufferAddress,
      isWritable: true,
      isSigner: false,
    },
    {
      pubkey: spillAddress,
      isWritable: true,
      isSigner: false,
    },
    {
      pubkey: SYSVAR_RENT_PUBKEY,
      isWritable: false,
      isSigner: false,
    },
    {
      pubkey: SYSVAR_CLOCK_PUBKEY,
      isWritable: false,
      isSigner: false,
    },
    {
      pubkey: upgradeAuthority,
      isWritable: false,
      isSigner: true,
    },
  ];

  return new TransactionInstruction({
    keys,
    programId: bpfUpgradableLoaderId,
    data: Buffer.from([3, 0, 0, 0]), // Upgrade instruction bincode
  });
}