Feat:add feature WhereHas in db

Author: mehdi-fathi

src/QueryFilter/Detection/ConditionsDetect/DB/DBBuilderQueryByCondition.php

@@ -10,6 +10,7 @@
 use eloquentFilter\QueryFilter\Queries\DB\WhereCustom;
 use eloquentFilter\QueryFilter\Queries\DB\WhereDate;
 use eloquentFilter\QueryFilter\Queries\DB\WhereDoesntHave;
+use eloquentFilter\QueryFilter\Queries\DB\WhereHas;
 use eloquentFilter\QueryFilter\Queries\DB\WhereIn;
 use eloquentFilter\QueryFilter\Queries\DB\WhereLike;
 use eloquentFilter\QueryFilter\Queries\DB\WhereOr;
@@ -41,7 +42,7 @@ public function build($condition): ?string
             'WhereByOpt' => WhereByOpt::class,
             'WhereDate' => WhereDate::class,
             'WhereDoesntHave' => WhereDoesntHave::class,
-            // 'WhereHas' => WhereHas::class,
+            'WhereHas' => WhereHas::class,
             'WhereIn' => WhereIn::class,
             'WhereLike' => WhereLike::class,
             'WhereOr' => WhereOr::class,

src/QueryFilter/Queries/DB/WhereHas.php

@@ -3,21 +3,45 @@
 namespace eloquentFilter\QueryFilter\Queries\DB;
 
 use eloquentFilter\QueryFilter\Queries\BaseClause;
-use Illuminate\Database\DB\Builder;
+use Illuminate\Database\Query\Expression as Raw;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Str;
 
 /**
  * Class WhereHas.
+ * Implements WhereHas functionality for DB queries using EXISTS clause
  */
 class WhereHas extends BaseClause
 {
     /**
+     * Apply the WhereHas condition to the DB query
+     * 
      * @param $query
-     *
-     * @return Builder
+     * @return \Illuminate\Database\Query\Builder
      */
     public function apply($query)
     {
-        //todo implement later
-        return ;
+        $field_row = explode('.', $this->filter);
+        $field_row = end($field_row);
+        
+        $relation = str_replace('.'.$field_row, '', $this->filter);
+        $relationTable = Str::plural($relation);
+        
+        $value = $this->values;
+        $from = $query->from;
+
+        return $query->whereExists(function ($q) use ($relationTable, $field_row, $value, $from) {
+            $foreignKey = sprintf('%s.%s_id', $from, Str::singular($relationTable));
+            
+            $q->select(DB::raw(1))
+              ->from($relationTable)
+              ->whereRaw("$relationTable.id = $foreignKey");
+
+            if (is_array($value)) {
+                $q->whereIn($field_row, $value);
+            } else {
+                $q->where($field_row, $value);
+            }
+        });
     }
 }