feat: add xcm dry run api

app/src/hooks/useParaspellApi.tsx

@@ -7,7 +7,7 @@ import { getSenderAddress } from '@/utils/address'
 import { trackTransferMetrics } from '@/utils/analytics'
 import { isProduction } from '@/utils/env'
 import { handleObservableEvents } from '@/utils/papi'
-import { createTx, moonbeamTransfer } from '@/utils/paraspell'
+import { createTx, dryRun, moonbeamTransfer } from '@/utils/paraspell'
 import { txWasCancelled } from '@/utils/transfer'
 import { captureException } from '@sentry/nextjs'
 import { switchChain } from '@wagmi/core'
@@ -48,8 +48,6 @@ const useParaspellApi = () => {
     const date = new Date()
     await addToOngoingTransfers(hash, params, senderAddress, tokenUSDValue, date, setStatus)
 
-    // TODO: figure out how to add crosschain event stuff
-
     // We intentionally track the transfer on submit. The intention was clear, and if it fails somehow we see it in sentry and fix it.
     if (params.environment === Environment.Mainnet && isProduction) {
       trackTransferMetrics({
@@ -79,6 +77,13 @@ const useParaspellApi = () => {
     if (!account.pjsSigner?.signPayload || !account.pjsSigner?.signRaw)
       throw new Error('Signer not found')
 
+    // Validate the transfer
+    setStatus('Validating')
+
+    const validationResult = await validate(params)
+    if (validationResult.dryRunSupported && !validationResult.success)
+      throw new Error(`Transfer dry run failed: ${validationResult.error}`)
+
     const tx = await createTx(params, params.sourceChain.rpcConnection)
     setStatus('Signing')
 
@@ -152,6 +157,38 @@ const useParaspellApi = () => {
     }
   }
 
+  interface DryRunResult {
+    dryRunSupported: boolean
+    success: boolean
+    error?: string
+    fee?: bigint
+  }
+
+  const validate = async (params: TransferParams): Promise<DryRunResult> => {
+    try {
+      const dryRunResult = await dryRun(params, params.sourceChain.rpcConnection)
+
+      const res: DryRunResult = {
+        dryRunSupported: true,
+        success: dryRunResult.success,
+      }
+
+      if (dryRunResult.success) res.fee = dryRunResult.fee
+      else {
+        res.error = dryRunResult.failureReason
+        console.error('Dry run failed:', dryRunResult.failureReason)
+        captureException(new Error(`Dry run failed: ${dryRunResult.failureReason}`))
+      }
+
+      return res
+    } catch (e: unknown) {
+      if (e instanceof Error && e.message.includes('DryRunApi is not available'))
+        return { dryRunSupported: false, success: false, error: e.message }
+
+      return { dryRunSupported: true, success: false, error: (e as Error).message }
+    }
+  }
+
   const addToOngoingTransfers = async (
     txHash: string,
     params: TransferParams,

app/src/hooks/useSnowbridgeApi.tsx

@@ -50,7 +50,6 @@ const useSnowbridgeApi = () => {
       onComplete,
     } = params
 
-    setStatus('Loading')
     try {
       if (snowbridgeContext === undefined) {
         addNotification({

app/src/utils/paraspell.ts

@@ -8,6 +8,7 @@ import {
   getAllAssetsSymbols,
   getTNode,
   TCurrencyCore,
+  TDryRunResult,
   TNodeDotKsmWithRelayChains,
   type TPapiTransaction,
 } from '@paraspell/sdk'
@@ -79,6 +80,36 @@ export const moonbeamTransfer = async (
     .build()
 }
 
+/**
+ * Dry run a transfer using Paraspell.
+ *
+ * @param params - The transfer parameters
+ * @param wssEndpoint - An optional wss chain endpoint to connect to a specific blockchain.
+ * @returns - A Promise that resolves a dry run result.
+ * @throws - An error if the dry run api is not available.
+ */
+export const dryRun = async (
+  params: TransferParams,
+  wssEndpoint?: string,
+): Promise<TDryRunResult> => {
+  const { environment, sourceChain, destinationChain, token, amount, recipient } = params
+
+  const relay = getRelayNode(environment)
+  const sourceChainFromId = getTNode(sourceChain.chainId, relay)
+  const destinationChainFromId = getTNode(destinationChain.chainId, relay)
+  if (!sourceChainFromId || !destinationChainFromId)
+    throw new Error('Dry Run failed: chain id not found.')
+
+  const currencyId = getCurrencyId(environment, sourceChainFromId, sourceChain.uid, token)
+
+  return await Builder(wssEndpoint)
+    .from(sourceChainFromId)
+    .to(destinationChainFromId)
+    .currency({ ...currencyId, amount })
+    .address(recipient)
+    .dryRun()
+}
+
 export const getTokenSymbol = (sourceChain: TNodeDotKsmWithRelayChains, token: Token) => {
   const supportedAssets = getAllAssetsSymbols(sourceChain)