add getTokenBalance operation to token Module

packages/js/src/plugins/psyoptionsAmericanInstrumentModule/helpers.ts

@@ -120,13 +120,20 @@ export const prepareAmericanOptions = async (
     ) {
       ataTxBuilderArray.push(underlyingToken.txBuilder);
     }
+    const { tokenBalance } = await convergence.tokens().getTokenBalance({
+      mintAddress: optionMarket.optionMint,
+      owner: caller,
+      mintDecimals: PsyoptionsAmericanInstrument.decimals,
+    });
+
+    const tokensToMint = amount - tokenBalance;
     const ixWithSigners =
       await psyoptionsAmerican.instructions.mintOptionInstruction(
         americanProgram,
         optionToken.ataPubKey,
         writerToken.ataPubKey,
         underlyingToken.ataPubKey,
-        new BN(amount!),
+        new BN(tokensToMint!),
         optionMarket as psyoptionsAmerican.OptionMarketWithKey
       );
     ixWithSigners.ix.keys[0] = {

packages/js/src/plugins/psyoptionsEuropeanInstrumentModule/helpers.ts

@@ -184,14 +184,26 @@ export const prepareEuropeanOptions = async (
     ) {
       ataTxBuilderArray.push(writerDestination.txBuilder);
     }
+
+    const { tokenBalance } = await convergence.tokens().getTokenBalance({
+      mintAddress:
+        leg.optionType == psyoptionsEuropean.OptionType.PUT
+          ? euroMeta.putWriterMint
+          : euroMeta.callWriterMint,
+      owner: caller,
+      mintDecimals: PsyoptionsEuropeanInstrument.decimals,
+    });
+
+    const tokensToMint = amount - tokenBalance;
+
     const { instruction: ix } = psyoptionsEuropean.instructions.mintOptions(
       europeanProgram,
       leg.optionMetaPubKey,
       euroMeta as psyoptionsEuropean.EuroMeta,
       minterCollateralKey,
       optionDestination.ataPubKey,
       writerDestination.ataPubKey,
-      addDecimals(amount, PsyoptionsEuropeanInstrument.decimals),
+      addDecimals(tokensToMint, PsyoptionsEuropeanInstrument.decimals),
       leg.optionType
     );
 

packages/js/src/plugins/tokenModule/TokenClient.ts

@@ -17,6 +17,8 @@ import {
   findTokenWithMintByMintOperation,
   FreezeTokensInput,
   freezeTokensOperation,
+  GetTokenBalanceInput,
+  getTokenBalanceOperation,
   MintTokensInput,
   mintTokensOperation,
   RevokeTokenDelegateAuthorityInput,
@@ -233,4 +235,11 @@ export class TokenClient {
       .operations()
       .execute(revokeTokenDelegateAuthorityOperation(input), options);
   }
+
+  /** {@inheritDoc getTokenBalanceOperation } */
+  getTokenBalance(input: GetTokenBalanceInput, options?: OperationOptions) {
+    return this.convergence
+      .operations()
+      .execute(getTokenBalanceOperation(input), options);
+  }
 }

packages/js/src/plugins/tokenModule/operations/getTokenBalance.ts

@@ -0,0 +1,91 @@
+import { PublicKey } from '@solana/web3.js';
+
+import BN from 'bn.js';
+import type { Convergence } from '../../../Convergence';
+import { Operation, OperationHandler, useOperation } from '../../../types';
+
+const Key = 'GetTokenBalance' as const;
+
+/**
+ * Get token Balance.
+ *
+ * ```ts
+ * await convergence
+ *   .tokens()
+ *   .getTokenBalance({
+ *     mintAddress,
+ *     owner,
+ *     mintDecimals
+ *   };
+ * ```
+ *
+ * @group Operations
+ * @category Constructors
+ */
+export const getTokenBalanceOperation =
+  useOperation<GetTokenBalanceOperation>(Key);
+
+/**
+ * @group Operations
+ * @category Types
+ */
+export type GetTokenBalanceOperation = Operation<
+  typeof Key,
+  GetTokenBalanceInput,
+  GetTokenBalanceOutput
+>;
+
+/**
+ * @group Operations
+ * @category Inputs
+ */
+export type GetTokenBalanceInput = {
+  /** The address of the mint account. */
+  mintAddress: PublicKey;
+  /** The address of  ATA owner */
+  owner: PublicKey;
+  /** mint decimals*/
+  mintDecimals: number;
+};
+
+/**
+ * @group Operations
+ * @category Outputs
+ */
+export type GetTokenBalanceOutput = {
+  /** The blockchain response from sending and confirming the transaction. */
+  tokenBalance: number;
+};
+
+/**
+ * @group Operations
+ * @category Handlers
+ */
+export const getTokenBalanceOperationHandler: OperationHandler<GetTokenBalanceOperation> =
+  {
+    async handle(
+      operation: GetTokenBalanceOperation,
+      convergence: Convergence
+    ): Promise<GetTokenBalanceOutput> {
+      const { mintAddress, owner, mintDecimals } = operation.input;
+
+      const ataAddress = convergence.tokens().pdas().associatedTokenAccount({
+        mint: mintAddress,
+        owner,
+      });
+      try {
+        const ata = await convergence
+          .tokens()
+          .findTokenByAddress({ address: ataAddress });
+        return {
+          tokenBalance: ata.amount.basisPoints
+            .div(new BN(Math.pow(10, mintDecimals)))
+            .toNumber(),
+        };
+      } catch (e) {
+        return {
+          tokenBalance: 0,
+        };
+      }
+    },
+  };

packages/js/src/plugins/tokenModule/operations/index.ts

@@ -11,3 +11,4 @@ export * from './mintTokens';
 export * from './revokeTokenDelegateAuthority';
 export * from './sendTokens';
 export * from './thawTokens';
+export * from './getTokenBalance';

packages/js/src/plugins/tokenModule/plugin.ts

@@ -18,6 +18,8 @@ import {
   findTokenWithMintByMintOperationHandler,
   freezeTokensOperation,
   freezeTokensOperationHandler,
+  getTokenBalanceOperationHandler,
+  getTokenBalanceOperation,
   mintTokensOperation,
   mintTokensOperationHandler,
   revokeTokenDelegateAuthorityOperation,
@@ -94,6 +96,8 @@ export const tokenModule = (): ConvergencePlugin => ({
     op.register(sendTokensOperation, sendTokensOperationHandler);
     op.register(thawTokensOperation, thawTokensOperationHandler);
 
+    op.register(getTokenBalanceOperation, getTokenBalanceOperationHandler);
+
     convergence.tokens = function () {
       return new TokenClient(this);
     };