Fix https://github.com/firefly-iii/firefly-iii/issues/7124

app/Validation/Account/WithdrawalValidation.php

@@ -108,6 +108,7 @@ trait WithdrawalValidation
             if (null !== $found) {
                 $type = $found->accountType->type;
                 if (in_array($type, $validTypes, true)) {
+                    $this->destination = $found;
                     return true;
                 }
                 $this->destError = (string)trans('validation.withdrawal_dest_bad_data', ['id' => $accountId, 'name' => $accountName]);

app/Validation/CurrencyValidation.php

@@ -43,6 +43,9 @@ trait CurrencyValidation
      */
     protected function validateForeignCurrencyInformation(Validator $validator): void
     {
+        if($validator->errors()->count() > 0) {
+            return;
+        }
         Log::debug('Now in validateForeignCurrencyInformation()');
         $transactions = $this->getTransactionsArray($validator);
 

app/Validation/GroupValidation.php

@@ -90,6 +90,9 @@ trait GroupValidation
      */
     protected function validateDescriptions(Validator $validator): void
     {
+        if($validator->errors()->count() > 0) {
+            return;
+        }
         Log::debug('Now in GroupValidation::validateDescriptions()');
         $transactions      = $this->getTransactionsArray($validator);
         $validDescriptions = 0;
@@ -113,6 +116,9 @@ trait GroupValidation
      */
     protected function validateGroupDescription(Validator $validator): void
     {
+        if($validator->errors()->count() > 0) {
+            return;
+        }
         Log::debug('Now in validateGroupDescription()');
         $data         = $validator->getData();
         $transactions = $this->getTransactionsArray($validator);

app/Validation/TransactionValidation.php

@@ -43,6 +43,9 @@ trait TransactionValidation
      */
     public function validateAccountInformation(Validator $validator): void
     {
+        if ($validator->errors()->count() > 0) {
+            return;
+        }
         Log::debug('Now in validateAccountInformation (TransactionValidation) ()');
         $transactions = $this->getTransactionsArray($validator);
         $data         = $validator->getData();
@@ -137,9 +140,49 @@ trait TransactionValidation
             $validator->errors()->add(sprintf('transactions.%d.destination_id', $index), $accountValidator->destError);
             $validator->errors()->add(sprintf('transactions.%d.destination_name', $index), $accountValidator->destError);
         }
-
         // sanity check for reconciliation accounts. They can't both be null.
         $this->sanityCheckReconciliation($validator, $transactionType, $index, $source, $destination);
+
+        // deposit and the source is a liability or an asset account with a different
+        // currency than submitted? then the foreign currency info must be present as well (and filled in).
+        if (0 === $validator->errors()->count() && null !== $accountValidator->source && TransactionType::DEPOSIT === ucfirst($transactionType)) {
+            $accountType = $accountValidator?->source?->accountType?->type;
+            if (in_array($accountType, config('firefly.valid_currency_account_types'), true) && !$this->hasForeignCurrencyInfo($transaction)) {
+                $validator->errors()->add(sprintf('transactions.%d.foreign_amount', $index), (string)trans('validation.require_foreign_currency'));
+            }
+        }
+
+        // withdrawal or transfer and the destination is a liability or an asset account with a different
+        // currency than submitted? then the foreign currency info must be present as well (and filled in).
+        if (0 === $validator->errors()->count() && null !== $accountValidator->destination &&
+            (TransactionType::WITHDRAWAL === ucfirst($transactionType) || (TransactionType::TRANSFER === ucfirst($transactionType)))) {
+            $accountType = $accountValidator?->destination?->accountType?->type;
+            if (in_array($accountType, config('firefly.valid_currency_account_types'), true) && !$this->hasForeignCurrencyInfo($transaction)) {
+                $validator->errors()->add(sprintf('transactions.%d.foreign_amount', $index), (string)trans('validation.require_foreign_currency'));
+            }
+        }
+        // account validator has a valid source and a valid destination
+    }
+
+    /**
+     * @param  array  $transaction
+     * @return bool
+     */
+    private function hasForeignCurrencyInfo(array $transaction): bool
+    {
+        if (!array_key_exists('foreign_currency_code', $transaction) && !array_key_exists('foreign_currency_id', $transaction)) {
+            return false;
+        }
+        if (!array_key_exists('foreign_amount', $transaction)) {
+            return false;
+        }
+        if ('' === $transaction['foreign_amount']) {
+            return false;
+        }
+        if (bccomp('0', $transaction['foreign_amount']) === 0) {
+            return false;
+        }
+        return true;
     }
 
     /**
@@ -324,6 +367,9 @@ trait TransactionValidation
      */
     public function validateOneTransaction(Validator $validator): void
     {
+        if ($validator->errors()->count() > 0) {
+            return;
+        }
         Log::debug('Now in validateOneTransaction()');
         $transactions = $this->getTransactionsArray($validator);
         // need at least one transaction
@@ -341,6 +387,9 @@ trait TransactionValidation
      */
     public function validateTransactionArray(Validator $validator): void
     {
+        if ($validator->errors()->count() > 0) {
+            return;
+        }
         $transactions = $this->getTransactionsArray($validator);
         foreach ($transactions as $key => $value) {
             if (!is_int($key)) {
@@ -359,6 +408,9 @@ trait TransactionValidation
      */
     public function validateTransactionTypes(Validator $validator): void
     {
+        if ($validator->errors()->count() > 0) {
+            return;
+        }
         Log::debug('Now in validateTransactionTypes()');
         $transactions = $this->getTransactionsArray($validator);
 
@@ -427,6 +479,9 @@ trait TransactionValidation
      */
     private function validateEqualAccounts(Validator $validator): void
     {
+        if ($validator->errors()->count() > 0) {
+            return;
+        }
         Log::debug('Now in validateEqualAccounts()');
         $transactions = $this->getTransactionsArray($validator);
 

resources/lang/en_US/validation.php

@@ -56,6 +56,7 @@ return [
     'require_currency_info'          => 'The content of this field is invalid without currency information.',
     'not_transfer_account'           => 'This account is not an account that can be used for transfers.',
     'require_currency_amount'        => 'The content of this field is invalid without foreign amount information.',
+    'require_foreign_currency'       => 'This field requires a number',
     'equal_description'              => 'Transaction description should not equal global description.',
     'file_invalid_mime'              => 'File ":name" is of type ":mime" which is not accepted as a new upload.',
     'file_too_large'                 => 'File ":name" is too large.',