solana-program-examples/tokens/escrow/native/tests/instruction.ts

import { ASSOCIATED_TOKEN_PROGRAM_ID, TOKEN_PROGRAM_ID } from '@solana/spl-token';
import { PublicKey, SystemProgram, TransactionInstruction } from '@solana/web3.js';
import BN from 'bn.js';
import * as borsh from 'borsh';

class Assignable {
  constructor(properties) {
    for (const [key, value] of Object.entries(properties)) {
      this[key] = value;
    }
  }
}

enum EscrowInstruction {
  MakeOffer = 0,
  TakeOffer = 1,
}

class MakeOffer extends Assignable {
  toBuffer() {
    return Buffer.from(borsh.serialize(MakeOfferSchema, this));
  }
}

const MakeOfferSchema = new Map([
  [
    MakeOffer,
    {
      kind: 'struct',
      fields: [
        ['instruction', 'u8'],
        ['id', 'u64'],
        ['token_a_offered_amount', 'u64'],
        ['token_b_wanted_amount', 'u64'],
      ],
    },
  ],
]);

class TakeOffer extends Assignable {
  toBuffer() {
    return Buffer.from(borsh.serialize(TakeOfferSchema, this));
  }
}

const TakeOfferSchema = new Map([
  [
    TakeOffer,
    {
      kind: 'struct',
      fields: [['instruction', 'u8']],
    },
  ],
]);

export function buildMakeOffer(props: {
  id: BN;
  token_a_offered_amount: BN;
  token_b_wanted_amount: BN;
  offer: PublicKey;
  mint_a: PublicKey;
  mint_b: PublicKey;
  maker_token_a: PublicKey;
  vault: PublicKey;
  maker: PublicKey;
  payer: PublicKey;
  programId: PublicKey;
}) {
  const ix = new MakeOffer({
    instruction: EscrowInstruction.MakeOffer,
    id: props.id,
    token_a_offered_amount: props.token_a_offered_amount,
    token_b_wanted_amount: props.token_b_wanted_amount,
  });

  return new TransactionInstruction({
    keys: [
      {
        pubkey: props.offer,
        isSigner: false,
        isWritable: true,
      },
      {
        pubkey: props.mint_a,
        isSigner: false,
        isWritable: false,
      },
      {
        pubkey: props.mint_b,
        isSigner: false,
        isWritable: false,
      },
      {
        pubkey: props.maker_token_a,
        isSigner: false,
        isWritable: true,
      },
      {
        pubkey: props.vault,
        isSigner: false,
        isWritable: true,
      },
      {
        pubkey: props.maker,
        isSigner: true,
        isWritable: true,
      },
      {
        pubkey: props.payer,
        isSigner: true,
        isWritable: true,
      },
      {
        pubkey: TOKEN_PROGRAM_ID,
        isSigner: false,
        isWritable: false,
      },
      {
        pubkey: ASSOCIATED_TOKEN_PROGRAM_ID,
        isSigner: false,
        isWritable: false,
      },
      { pubkey: SystemProgram.programId, isSigner: false, isWritable: false },
    ],
    programId: props.programId,
    data: ix.toBuffer(),
  });
}

export function buildTakeOffer(props: {
  offer: PublicKey;
  mint_a: PublicKey;
  mint_b: PublicKey;
  maker_token_b: PublicKey;
  taker_token_a: PublicKey;
  taker_token_b: PublicKey;
  vault: PublicKey;
  taker: PublicKey;
  maker: PublicKey;
  payer: PublicKey;
  programId: PublicKey;
}) {
  const ix = new TakeOffer({
    instruction: EscrowInstruction.TakeOffer,
  });

  return new TransactionInstruction({
    keys: [
      {
        pubkey: props.offer,
        isSigner: false,
        isWritable: true,
      },
      {
        pubkey: props.mint_a,
        isSigner: false,
        isWritable: false,
      },
      {
        pubkey: props.mint_b,
        isSigner: false,
        isWritable: false,
      },
      {
        pubkey: props.maker_token_b,
        isSigner: false,
        isWritable: true,
      },
      {
        pubkey: props.taker_token_a,
        isSigner: false,
        isWritable: true,
      },
      {
        pubkey: props.taker_token_b,
        isSigner: false,
        isWritable: true,
      },
      {
        pubkey: props.vault,
        isSigner: false,
        isWritable: true,
      },
      {
        pubkey: props.maker,
        isSigner: false,
        isWritable: false,
      },
      {
        pubkey: props.taker,
        isSigner: true,
        isWritable: true,
      },
      {
        pubkey: props.payer,
        isSigner: true,
        isWritable: true,
      },
      {
        pubkey: TOKEN_PROGRAM_ID,
        isSigner: false,
        isWritable: false,
      },
      {
        pubkey: ASSOCIATED_TOKEN_PROGRAM_ID,
        isSigner: false,
        isWritable: false,
      },
      { pubkey: SystemProgram.programId, isSigner: false, isWritable: false },
    ],
    programId: props.programId,
    data: ix.toBuffer(),
  });
}