Add rule for unique account number.

app/Api/V1/Requests/AccountStoreRequest.php

@@ -26,6 +26,8 @@ namespace FireflyIII\Api\V1\Requests;
 
 use FireflyIII\Models\Location;
 use FireflyIII\Rules\IsBoolean;
+use FireflyIII\Rules\UniqueAccountNumber;
+use FireflyIII\Rules\UniqueIban;
 use FireflyIII\Support\Request\AppendsLocationData;
 use FireflyIII\Support\Request\ChecksLogin;
 use FireflyIII\Support\Request\ConvertsDataTypes;
@@ -98,12 +100,13 @@ class AccountStoreRequest extends FormRequest
         $accountRoles   = implode(',', config('firefly.accountRoles'));
         $types          = implode(',', array_keys(config('firefly.subTitlesByIdentifier')));
         $ccPaymentTypes = implode(',', array_keys(config('firefly.ccTypes')));
+        $type           = $this->string('type');
         $rules          = [
             'name'                 => 'required|min:1|uniqueAccountForUser',
             'type'                 => 'required|' . sprintf('in:%s', $types),
-            'iban'                 => 'iban|nullable',
+            'iban'                 => ['iban', 'nullable', new UniqueIban(null, $type)],
             'bic'                  => 'bic|nullable',
-            'account_number'       => 'between:1,255|nullable|uniqueAccountNumberForUser',
+            'account_number'       => ['between:1,255', 'nullable', new UniqueAccountNumber(null, $type)],
             'opening_balance'      => 'numeric|required_with:opening_balance_date|nullable',
             'opening_balance_date' => 'date|required_with:opening_balance|nullable',
             'virtual_balance'      => 'numeric|nullable',
@@ -122,6 +125,7 @@ class AccountStoreRequest extends FormRequest
             'interest_period'      => 'required_if:type,liability|in:daily,monthly,yearly',
             'notes'                => 'min:0|max:65536',
         ];
+
         return Location::requestRules($rules);
     }
 }

app/Api/V1/Requests/AccountUpdateRequest.php

@@ -26,6 +26,8 @@ namespace FireflyIII\Api\V1\Requests;
 
 use FireflyIII\Models\Location;
 use FireflyIII\Rules\IsBoolean;
+use FireflyIII\Rules\UniqueAccountNumber;
+use FireflyIII\Rules\UniqueIban;
 use FireflyIII\Support\Request\AppendsLocationData;
 use FireflyIII\Support\Request\ChecksLogin;
 use FireflyIII\Support\Request\ConvertsDataTypes;
@@ -103,9 +105,9 @@ class AccountUpdateRequest extends FormRequest
         $rules = [
             'name'                 => sprintf('min:1|uniqueAccountForUser:%d', $account->id),
             'type'                 => sprintf('in:%s', $types),
-            'iban'                 => 'iban|nullable',
+            'iban'                 => ['iban', 'nullable', new UniqueIban($account, $this->nullableString('type'))],
             'bic'                  => 'bic|nullable',
-            'account_number'       => sprintf('between:1,255|nullable|uniqueAccountNumberForUser:%d', $account->id),
+            'account_number'       => ['between:1,255', 'nullable', new UniqueAccountNumber($account, $this->nullableString('type'))],
             'opening_balance'      => 'numeric|required_with:opening_balance_date|nullable',
             'opening_balance_date' => 'date|required_with:opening_balance|nullable',
             'virtual_balance'      => 'numeric|nullable',
@@ -124,6 +126,7 @@ class AccountUpdateRequest extends FormRequest
             'interest_period'      => 'required_if:type,liability|in:daily,monthly,yearly',
             'notes'                => 'min:0|max:65536',
         ];
+
         return Location::requestRules($rules);
     }
 }

app/Rules/UniqueAccountNumber.php

@@ -0,0 +1,160 @@
+<?php
+/**
+ * UniqueAccountNumber.php
+ * Copyright (c) 2021 james@firefly-iii.org
+ *
+ * This file is part of Firefly III (https://github.com/firefly-iii).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Rules;
+
+use FireflyIII\Models\Account;
+use FireflyIII\Models\AccountMeta;
+use FireflyIII\Models\AccountType;
+use Illuminate\Contracts\Validation\Rule;
+use Log;
+
+/**
+ * Class UniqueAccountNumber
+ */
+class UniqueAccountNumber implements Rule
+{
+    private ?Account $account;
+    private ?string $expectedType;
+
+    /**
+     * Create a new rule instance.
+     *
+     * @codeCoverageIgnore
+     *
+     * @param Account|null $account
+     * @param string|null  $expectedType
+     */
+    public function __construct(?Account $account, ?string $expectedType)
+    {
+        $this->account      = $account;
+        $this->expectedType = $expectedType;
+        // a very basic fix to make sure we get the correct account type:
+        if ('expense' === $expectedType) {
+            $this->expectedType = AccountType::EXPENSE;
+        }
+        if ('revenue' === $expectedType) {
+            $this->expectedType = AccountType::REVENUE;
+        }
+        if ('asset' === $expectedType) {
+            $this->expectedType = AccountType::ASSET;
+        }
+    }
+
+    /**
+     * Get the validation error message.
+     *
+     * @codeCoverageIgnore
+     *
+     * @return string
+     */
+    public function message(): string
+    {
+        return (string)trans('validation.unique_account_number_for_user');
+    }
+
+    /**
+     * Determine if the validation rule passes.
+     *
+     * @param string $attribute
+     * @param mixed  $value
+     *
+     * @return bool
+     *
+     */
+    public function passes($attribute, $value): bool
+    {
+        if (!auth()->check()) {
+            return true; // @codeCoverageIgnore
+        }
+        if (null === $this->expectedType) {
+            return true; // @codeCoverageIgnore
+        }
+        $maxCounts = $this->getMaxOccurrences();
+
+        foreach ($maxCounts as $type => $max) {
+            $count = $this->countHits($type, $value);
+            Log::debug(sprintf('Count for "%s" and account number "%s" is %d', $type, $value, $count));
+            if ($count > $max) {
+                Log::debug(
+                    sprintf(
+                        'account number "%s" is in use with %d account(s) of type "%s", which is too much for expected type "%s"',
+                        $value, $count, $type, $this->expectedType
+                    )
+                );
+
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * @param string $type
+     * @param string $accountNumber
+     *
+     * @return int
+     */
+    private function countHits(string $type, string $accountNumber): int
+    {
+        $query = AccountMeta
+            ::leftJoin('accounts','accounts.id','=','account_meta.account_id')
+            ->leftJoin('account_types', 'account_types.id', '=', 'accounts.account_type_id')
+            ->where('accounts.user_id', auth()->user()->id)
+            ->where('account_meta.name','=','account_number')
+            ->where('account_meta.data',json_encode($accountNumber));
+
+        if (null !== $this->account) {
+            $query->where('accounts.id', '!=', $this->account->id);
+        }
+
+        return $query->count();
+    }
+
+    /**
+     * @return array
+     *
+     */
+    private function getMaxOccurrences(): array
+    {
+        $maxCounts = [
+            AccountType::ASSET   => 0,
+            AccountType::EXPENSE => 0,
+            AccountType::REVENUE => 0,
+        ];
+
+        if ('expense' === $this->expectedType || AccountType::EXPENSE === $this->expectedType) {
+            // IBAN should be unique amongst expense and asset accounts.
+            // may appear once in revenue accounts
+            $maxCounts[AccountType::REVENUE] = 1;
+        }
+        if ('revenue' === $this->expectedType || AccountType::REVENUE === $this->expectedType) {
+            // IBAN should be unique amongst revenue and asset accounts.
+            // may appear once in expense accounts
+            $maxCounts[AccountType::EXPENSE] = 1;
+        }
+
+        return $maxCounts;
+    }
+}

app/Rules/UniqueIban.php

@@ -33,11 +33,8 @@ use Log;
  */
 class UniqueIban implements Rule
 {
-    /** @var Account */
-    private $account;
-
-    /** @var string */
-    private $expectedType;
+    private ?Account $account;
+    private ?string $expectedType;
 
     /**
      * Create a new rule instance.
@@ -51,6 +48,16 @@ class UniqueIban implements Rule
     {
         $this->account      = $account;
         $this->expectedType = $expectedType;
+        // a very basic fix to make sure we get the correct account type:
+        if ('expense' === $expectedType) {
+            $this->expectedType = AccountType::EXPENSE;
+        }
+        if ('revenue' === $expectedType) {
+            $this->expectedType = AccountType::REVENUE;
+        }
+        if ('asset' === $expectedType) {
+            $this->expectedType = AccountType::ASSET;
+        }
     }
 
     /**
@@ -68,8 +75,8 @@ class UniqueIban implements Rule
     /**
      * Determine if the validation rule passes.
      *
-     * @param  string $attribute
-     * @param  mixed  $value
+     * @param string $attribute
+     * @param mixed  $value
      *
      * @return bool
      *