Added filter by region

app/Nova/Filters/RegionFilter.php

@@ -0,0 +1,51 @@
+<?php
+
+namespace App\Nova\Filters;
+
+use App\Repos\System\Settings\Location\RegionRepo;
+use Laravel\Nova\Filters\Filter;
+use Laravel\Nova\Http\Requests\NovaRequest;
+
+class RegionFilter extends Filter
+{
+    /**
+     * The filter's component.
+     *
+     * @var string
+     */
+    public $component = 'select-filter';
+
+    /**
+     * Get the displayable name of the filter.
+     *
+     * @return string
+     */
+    public function name(): string
+    {
+        return __('Region');
+    }
+
+    /**
+     * Apply the filter to the given query.
+     *
+     * @param  \Laravel\Nova\Http\Requests\NovaRequest  $request
+     * @param  \Illuminate\Database\Eloquent\Builder  $query
+     * @param  mixed  $value
+     * @return \Illuminate\Database\Eloquent\Builder
+     */
+    public function apply(NovaRequest $request, $query, $value)
+    {
+        return $value ? $query->where('region', $value) : $query;
+    }
+
+    /**
+     * Get the filter's available options.
+     *
+     * @param  \Laravel\Nova\Http\Requests\NovaRequest  $request
+     * @return array
+     */
+    public function options(NovaRequest $request): array
+    {
+        return array_flip(RegionRepo::values());
+    }
+}