added freelancer invoice template (#254)

src/Invoice/CalculatorInterface.php

@@ -58,4 +58,18 @@ interface CalculatorInterface
      * @return string
      */
     public function getCurrency(): string;
+
+    /**
+     * Returns the percentage for the value-added tax (VAT) calculation.
+     *
+     * @return float
+     */
+    public function getVat(): ?float;
+
+    /**
+     * Returns the total amount of worked time in seconds.
+     *
+     * @return int
+     */
+    public function getTimeWorked(): int;
 }

src/Invoice/DefaultCalculator.php

@@ -62,7 +62,7 @@ class DefaultCalculator implements CalculatorInterface
     /**
      * @return float
      */
-    public function getVat()
+    public function getVat(): ?float
     {
         return $this->model->getTemplate()->getVat();
     }
@@ -97,4 +97,19 @@ class DefaultCalculator implements CalculatorInterface
     {
         return $this->model->getCustomer()->getCurrency();
     }
+
+    /**
+     * Returns the total amount of worked time in seconds.
+     *
+     * @return int
+     */
+    public function getTimeWorked(): int
+    {
+        $time = 0;
+        foreach ($this->model->getEntries() as $entry) {
+            $time += $entry->getDuration();
+        }
+
+        return $time;
+    }
 }

src/Invoice/ShortInvoiceCalculator.php

@@ -27,11 +27,16 @@ class ShortInvoiceCalculator extends DefaultCalculator
         foreach ($this->model->getEntries() as $entry) {
             $timesheet->setRate($timesheet->getRate() + $entry->getRate());
             $timesheet->setDuration($timesheet->getDuration() + $entry->getDuration());
+            $timesheet->setBegin($entry->getBegin());
             if (null === $timesheet->getActivity()) {
                 $timesheet->setActivity($entry->getActivity());
-                $timesheet->setEnd($entry->getEnd());
             }
-            $timesheet->setBegin($entry->getBegin());
+        }
+
+        if (null !== $this->model->getQuery()->getActivity()) {
+            $timesheet->setDescription($this->model->getQuery()->getActivity()->getName());
+        } elseif (null !== $this->model->getQuery()->getProject()) {
+            $timesheet->setDescription($this->model->getQuery()->getProject()->getName());
         }
 
         return [$timesheet];