Enable sac interactions (#35)

* Implement SAC transfer functionality in walletStore

* Implement SAC transfer functionality in walletStore

* Implement createContractTransferTransaction function

* made modifications

* modifications

* made modifications

* changes made

* fix a couple imports

---------

Co-authored-by: Nathan_akin <85641756+akintewe@users.noreply.github.com>
Co-authored-by: llama <llama@llama.fi>

Author: 3 people

src/lib/stellar/transactions.js

@@ -1,6 +1,6 @@
-import { TransactionBuilder, Networks, Operation, Asset, Memo, Horizon } from '@stellar/stellar-sdk'
+import Server from '@stellar/stellar-sdk'
+import { TransactionBuilder, Networks, Operation, Asset, Memo, Contract, Horizon, xdr, Address, StrKey, rpc, nativeToScVal } from '@stellar/stellar-sdk'
 import { error } from '@sveltejs/kit'
-
 /**
  * @module $lib/stellar/transactions
  * @description A collection of functions that will generate and return
@@ -12,6 +12,7 @@ import { error } from '@sveltejs/kit'
  * {@link createChangeTrustTransaction}
  * {@link createPathPaymentStrictSendTransaction}
  * {@link createPathPaymentStrictReceiveTransaction}
+ * {@link createContractTransferTransaction}
  */
 
 // We are setting a very high maximum fee, which increases our transaction's
@@ -22,6 +23,7 @@ const maxFeePerOperation = '100000'
 const horizonUrl = 'https://horizon-testnet.stellar.org'
 const networkPassphrase = Networks.TESTNET
 const standardTimebounds = 300 // 5 minutes for the user to review/sign/submit
+const rpcUrl = 'https://soroban-testnet.stellar.org'
 
 /**
  * For consistency, all functions in this module will return the same type of object.
@@ -185,7 +187,6 @@ export async function createChangeTrustTransaction({ source, asset, limit }) {
         network_passphrase: networkPassphrase,
     }
 }
-
 /**
  * Constructs and returns a Stellar transaction that will contain a path payment strict send operation to send/receive different assets.
  * @async
@@ -331,3 +332,47 @@ export async function createPathPaymentStrictReceiveTransaction({
         network_passphrase: networkPassphrase,
     }
 }
+
+/**
+ * Constructs and returns a Stellar transaction for transferring assets to a contract or account.
+ * @async
+ * @function createContractTransferTransaction
+ * @param {Object} opts Options object
+ * @param {string} opts.source Public Stellar address to use as the source account of the transaction
+ * @param {string} opts.destination Public Stellar address or contract ID to receive the transfer
+ * @param {string} opts.amount Amount of the asset to transfer
+ * @param {string} opts.asset Asset to be transferred (example: USDC:GBBD47IF6LWK7P7MDEVSCWR7DPUWV3NY3DTQEVFL4NAT4AQH3ZLLFLA5)
+ * @returns {Promise<TransactionResponse>} Object containing the relevant network passphrase and the built transaction envelope in XDR base64 encoding, ready to be signed and submitted
+ */
+export async function createContractTransferTransaction({ source, destination, amount, asset }) {
+    const server = new rpc.Server(rpcUrl)
+const sourceAccount = await server.getAccount(source)
+
+    const transaction = new TransactionBuilder(sourceAccount, {
+        networkPassphrase: networkPassphrase,
+        fee: maxFeePerOperation,
+    });
+
+    const [assetCode, assetIssuer] = asset.split(':');
+    const contractId = new Asset(assetCode, assetIssuer).contractId(networkPassphrase);
+    const contract = new Contract(contractId);
+
+    const transferOp = contract.call(
+        "transfer",
+        nativeToScVal(source, { type: 'address' }),
+        nativeToScVal(destination, { type: 'address' }),
+        nativeToScVal(amount, { type: 'i128' })
+    )
+    transaction.addOperation(transferOp);
+
+    const builtTransaction = transaction.setTimeout(standardTimebounds).build();
+
+    // Simulate the transaction
+    const rpcServer = new rpc.Server(rpcUrl);
+    const simulatedTx = await server.prepareTransaction(builtTransaction)
+
+    return {
+        transaction: simulatedTx.toXDR(),
+        network_passphrase: networkPassphrase,
+    };
+}

src/lib/stores/contactsStore.js

@@ -45,14 +45,14 @@ function createContactsStore() {
          * Adds a new contact entry to the list with the provided details.
          * @function add
          * @param {ContactEntry} contact Details of new contact entry to add to the list
-         * @throws Will throw an error if the new contact entry contains an invalid public key in the `address` field
+         * @throws Will throw an error if the new contact entry contains an invalid public key or contract address in the `address` field
          */
         add: (contact) =>
             update((list) => {
                 if (StrKey.isValidEd25519PublicKey(contact.address) || StrKey.isValidContract(contact.address)) {
                     return [...list, { ...contact, id: uuidv4() }]
                 } else {
-                    throw error(400, { message: 'invalid public key' })
+                    throw error(400, { message: 'invalid public key or contract address' })
                 }
             }),
 
@@ -83,6 +83,15 @@ function createContactsStore() {
                 return false
             }
         },
+
+        /**
+         * Checks if the given address is a contract address
+         * @param {string} address Address to check
+         * @returns {boolean} True if the address is a contract address, false otherwise
+         */
+        isContractAddress: (address) => {
+            return StrKey.isValidContract(address)
+        },
     }
 }
 

src/lib/stores/walletStore.js

@@ -129,4 +129,4 @@ const setupKeyManager = () => {
     keyManager.registerEncrypter(ScryptEncrypter)
 
     return keyManager
-}
+}

src/routes/dashboard/send/+page.svelte

@@ -44,6 +44,7 @@ features have been implemented:
         createPathPaymentStrictReceiveTransaction,
         createPathPaymentStrictSendTransaction,
         createPaymentTransaction,
+        createContractTransferTransaction,
     } from '$lib/stellar/transactions'
 
     // The `open` Svelte context is used to open the confirmation modal
@@ -62,7 +63,7 @@ features have been implemented:
     /** @type {boolean|null} */
     let createAccount = null
     let pathPayment = false
-    /** @type {import('stellar-sdk').ServerApi.PaymentPathRecord[]} */
+    /** @type {import('@stellar/stellar-sdk').Horizon.ServerApi.PaymentPathRecord[]} */
     let availablePaths = []
     let strictReceive = false
     let paymentXDR = ''
@@ -175,19 +176,27 @@ features have been implemented:
      * @function previewPaymentTransaction
      */
     const previewPaymentTransaction = async () => {
+        const destinationAddress = otherDestination ? otherPublicKey : destination;
         let { transaction, network_passphrase } = createAccount
             ? await createCreateAccountTransaction({
                   source: data.publicKey,
-                  destination: otherDestination ? otherPublicKey : destination,
+                  destination: destinationAddress,
                   amount: sendAmount,
                   memo: memo,
               })
+            : contacts.isContractAddress(destinationAddress)
+            ? await createContractTransferTransaction({
+                  source: data.publicKey,
+                  destination: destinationAddress,
+                  asset: sendAsset,
+                  amount: sendAmount,
+              })
             : pathPayment && strictReceive
             ? await createPathPaymentStrictReceiveTransaction({
                   source: data.publicKey,
                   sourceAsset: sendAsset,
                   sourceAmount: sendAmount,
-                  destination: otherDestination ? otherPublicKey : destination,
+                  destination: destinationAddress,
                   destinationAsset: receiveAsset,
                   destinationAmount: receiveAmount,
                   memo: memo,
@@ -197,22 +206,22 @@ features have been implemented:
                   source: data.publicKey,
                   sourceAsset: sendAsset,
                   sourceAmount: sendAmount,
-                  destination: otherDestination ? otherPublicKey : destination,
+                  destination: destinationAddress,
                   destinationAsset: receiveAsset,
                   destinationAmount: receiveAmount,
                   memo: memo,
               })
             : await createPaymentTransaction({
                   source: data.publicKey,
-                  destination: otherDestination ? otherPublicKey : destination,
+                  destination: destinationAddress,
                   asset: sendAsset,
                   amount: sendAmount,
                   memo: memo,
-              })
+              });
 
         // Set the component variables to hold the transaction details
-        paymentXDR = transaction
-        paymentNetwork = network_passphrase
+        paymentXDR = transaction;
+        paymentNetwork = network_passphrase;
 
         // Open the confirmation modal for the user to confirm or reject the
         // transaction. We provide our customized `onConfirm` function, but we
@@ -221,7 +230,7 @@ features have been implemented:
             transactionXDR: paymentXDR,
             transactionNetwork: paymentNetwork,
             onConfirm: onConfirm,
-        })
+        });
     }
 </script>
 
@@ -464,7 +473,6 @@ features have been implemented:
 
 <!-- Button -->
 <div class="form-control my-5">
-    <button class="btn-primary btn" on:click={previewPaymentTransaction}>Preview Transaction</button
-    >
+    <button class="btn-primary btn" on:click={previewPaymentTransaction}>Preview Transaction</button>
 </div>
 <!-- /Button -->