Initial commit

app/Services/PlanService.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace App\Services;
+
+use App\Models\Plan;
+use App\Models\User;
+use Illuminate\Support\Facades\DB;
+
+class PlanService
+{
+    public $plan;
+
+    public function __construct(int $planId)
+    {
+        $this->plan = Plan::lockForUpdate()->find($planId);
+    }
+
+    public function haveCapacity(): bool
+    {
+        if ($this->plan->capacity_limit === NULL) return true;
+        $count = self::countActiveUsers();
+        $count = $count[$this->plan->id]['count'] ?? 0;
+        return ($this->plan->capacity_limit - $count) > 0;
+    }
+
+    public static function countActiveUsers()
+    {
+        return User::select(
+            DB::raw("plan_id"),
+            DB::raw("count(*) as count")
+        )
+            ->where('plan_id', '!=', NULL)
+            ->where(function ($query) {
+                $query->where('expired_at', '>=', time())
+                    ->orWhere('expired_at', NULL);
+            })
+            ->groupBy("plan_id")
+            ->get()
+            ->keyBy('plan_id');
+    }
+}