From c3ccc4ccdfe37fab5f8d43348516628f1a8aa408 Mon Sep 17 00:00:00 2001
From: James Cole <thegrumpydictator@gmail.com>
Date: Thu, 8 Sep 2016 21:10:24 +0200
Subject: [PATCH] This should fix #308

Signed-off-by: James Cole <thegrumpydictator@gmail.com>
---
 app/Http/Controllers/CurrencyController.php | 47 ++++++++++++++++++---
 resources/lang/en_US/firefly.php            |  2 +-
 2 files changed, 41 insertions(+), 8 deletions(-)

diff --git a/app/Http/Controllers/CurrencyController.php b/app/Http/Controllers/CurrencyController.php
index a5da5fdcba..dc795f2f42 100644
--- a/app/Http/Controllers/CurrencyController.php
+++ b/app/Http/Controllers/CurrencyController.php
@@ -81,20 +81,19 @@ class CurrencyController extends Controller
     }
 
     /**
-     * @param CurrencyRepositoryInterface $repository
      * @param TransactionCurrency         $currency
      *
      * @return \Illuminate\Http\RedirectResponse|View
      */
-    public function delete(CurrencyRepositoryInterface $repository, TransactionCurrency $currency)
+    public function delete(TransactionCurrency $currency)
     {
-
-        if ($repository->countJournals($currency) > 0) {
+        if (!$this->canDeleteCurrency($currency)) {
             Session::flash('error', trans('firefly.cannot_delete_currency', ['name' => $currency->name]));
 
             return redirect(route('currency.index'));
         }
 
+
         // put previous url in session
         Session::put('currency.delete.url', URL::previous());
         Session::flash('gaEventCategory', 'currency');
@@ -106,15 +105,14 @@ class CurrencyController extends Controller
     }
 
     /**
-     * @param CurrencyRepositoryInterface $repository
      * @param TransactionCurrency         $currency
      *
      * @return \Illuminate\Http\RedirectResponse
      * @throws \Exception
      */
-    public function destroy(CurrencyRepositoryInterface $repository, TransactionCurrency $currency)
+    public function destroy(TransactionCurrency $currency)
     {
-        if ($repository->countJournals($currency) > 0) {
+        if (!$this->canDeleteCurrency($currency)) {
             Session::flash('error', trans('firefly.cannot_delete_currency', ['name' => $currency->name]));
 
             return redirect(route('currency.index'));
@@ -229,4 +227,39 @@ class CurrencyController extends Controller
 
     }
 
+    /**
+     * @param TransactionCurrency $currency
+     *
+     * @return bool
+     */
+    private function canDeleteCurrency(TransactionCurrency $currency): bool
+    {
+        $repository = app(CurrencyRepositoryInterface::class);
+
+        // has transactions still
+        if ($repository->countJournals($currency) > 0) {
+            return false;
+        }
+
+        // is the only currency left
+        if ($repository->get()->count() === 1) {
+            return false;
+        }
+
+        // is the default currency for the user or the system
+        $defaultCode = Preferences::get('currencyPreference', env('DEFAULT_CURRENCY', 'EUR'))->data;
+        if ($currency->code === $defaultCode) {
+            return false;
+        }
+
+        // is the default currency for the system
+        $defaultSystemCode = env('DEFAULT_CURRENCY', 'EUR');
+        if ($currency->code === $defaultSystemCode) {
+            return false;
+        }
+
+        // can be deleted
+        return true;
+    }
+
 }
diff --git a/resources/lang/en_US/firefly.php b/resources/lang/en_US/firefly.php
index ea1810f81f..b94dd8165f 100644
--- a/resources/lang/en_US/firefly.php
+++ b/resources/lang/en_US/firefly.php
@@ -359,7 +359,7 @@ return [
     'store_currency'                            => 'Store new currency',
     'update_currency'                           => 'Update currency',
     'new_default_currency'                      => ':name is now the default currency.',
-    'cannot_delete_currency'                    => 'Cannot delete :name because there are still transactions attached to it!',
+    'cannot_delete_currency'                    => 'Cannot delete :name because it is still in use.',
     'deleted_currency'                          => 'Currency :name deleted',
     'created_currency'                          => 'Currency :name created',
     'updated_currency'                          => 'Currency :name updated',