change default currency rate

app/Http/Controllers/Settings/Settings.php

@@ -6,6 +6,7 @@ use App\Abstracts\Http\Controller;
 use App\Http\Requests\Setting\Setting as Request;
 use App\Models\Common\Company;
 use App\Models\Module\Module;
+use App\Models\Setting\Currency;
 use App\Traits\DateTime;
 use App\Traits\Uploads;
 use App\Utilities\Installer;
@@ -113,6 +114,12 @@ class Settings extends Controller
                 user()->setAttribute('locale', $value)->save();
             }
 
+            if ($real_key == 'default.currency') {
+                $currency = Currency::code($value)->first();
+                $currency->rate = '1';
+                $currency->save();
+            }
+
             // If only 1 company
             if ($total_companies == 1) {
                 $this->oneCompany($real_key, $value);

app/Models/Setting/Currency.php

@@ -148,4 +148,16 @@ class Currency extends Model
 
         return $value;
     }
+
+    /**
+     * Scope currency by code.
+     *
+     * @param \Illuminate\Database\Eloquent\Builder $query
+     * @param mixed $code
+     * @return \Illuminate\Database\Eloquent\Builder
+     */
+    public function scopeCode($query, $code)
+    {
+        return $query->where($this->table . '.code', $code);
+    }
 }