Hoan thien core finance v2

app/Models/Contract.php

@@ -33,6 +33,11 @@ class Contract extends Model
         return $this->belongsTo(Product::class);
     }
 
+    public function paymentTemplate()
+    {
+        return $this->belongsTo(PaymentTemplate::class);
+    }
+
     public function customers()
     {
         return $this->belongsToMany(Customer::class, 'contract_customers')
@@ -73,6 +78,19 @@ class Contract extends Model
         return $this->hasMany(PaymentFine::class);
     }
 
+    /**
+     * Giá trị sau chiết khấu.
+     */
+    public function getFinalValueAttribute(): float
+    {
+        $result = \App\Services\DiscountEngine::calculate(
+            (float) $this->total_value,
+            $this->discount_details
+        );
+
+        return $result['final_value'];
+    }
+
     protected static function booted()
     {
         static::saving(function ($contract) {