import * as anchor from "@project-serum/anchor";
import {
  getAssociatedTokenAddress,
  getAccount,
  createAssociatedTokenAccountInstruction,
} from "@solana/spl-token";
import {
  TOKEN_METADATA_PROGRAM_ID,
  STRIKR_COLLECTION_MINT,
  STRIKR_TREASURY,
} from "../constants";
import { getStrikr, getStrikrAuthority } from "../utils";
import { requestComputeUnits } from "../actions/request-compute-units";

/**
 * Create a put option request as an option buyer
 * @param provider Anchor provider
 * @param assetNftMint Asset NFT which underlies the option
 * @param assetNftTokenAccount Token account containing the asset NFT
 * @returns Promise resolving to the transaction signature
 */
export const createPutOption = async (
  provider: anchor.AnchorProvider,
  assetNftMint: anchor.web3.PublicKey,
  strikePrice: anchor.BN,
  duration: anchor.BN,
  premium: anchor.BN,
  isGraceIncluded: boolean = false,
  assetNftTokenAccount?: anchor.web3.PublicKey
) => {
  const strikr = getStrikr(provider);
  const transaction = new anchor.web3.Transaction();

  const buyerPositionNftMintKeypair = new anchor.web3.Keypair();
  const buyerPositionNftMint = buyerPositionNftMintKeypair.publicKey;

  // Request additional compute units and attach the instruction
  const computeUnitsIx = requestComputeUnits(provider, 400_000, 0);

  transaction.add(computeUnitsIx);

  // Signer's position NFT ATA
  let buyerPositionNftTokenAccount = await getAssociatedTokenAddress(
    buyerPositionNftMint,
    provider.wallet.publicKey,
    true
  );

  // Use wallet's ATA as the NFT token account if not passed as argument
  if (!assetNftTokenAccount) {
    assetNftTokenAccount = await getAssociatedTokenAddress(
      assetNftMint,
      provider.wallet.publicKey
    );
    // Check if ATA exists, otherwise initialize it
    try {
      await getAccount(provider.connection, assetNftTokenAccount);
    } catch {
      transaction.add(
        createAssociatedTokenAccountInstruction(
          provider.wallet.publicKey,
          assetNftTokenAccount,
          provider.wallet.publicKey,
          assetNftMint
        )
      );
    }
  }

  const strikrAuthority = await getStrikrAuthority();
  const strikrAssetNftTokenAccount = await getAssociatedTokenAddress(
    assetNftMint,
    strikrAuthority,
    true
  );

  transaction.add(
    await strikr.methods
      .createPutOption(strikePrice, duration, premium, isGraceIncluded)
      .accounts({
        signer: provider.wallet.publicKey,
        assetNftMint,
        strikrTreasury: STRIKR_TREASURY,
        signerAssetNftTokenAccount: assetNftTokenAccount,
        strikrAssetNftTokenAccount,
        buyerPositionNftMint,
        buyerPositionNftTokenAccount,
        strikrCollectionMint: STRIKR_COLLECTION_MINT,
        tokenMetadataProgram: TOKEN_METADATA_PROGRAM_ID,
      })
      .instruction()
  );

  return await provider.sendAndConfirm(transaction, [
    buyerPositionNftMintKeypair,
  ]);
};