Added client usually pays in average days (#2876)

* Added client usually pays in average days

* Added translation for days label

* Code cleanup

* Added client usually pays in average days

* Added translation for days label

* Code cleanup

* Limit calculation to most recent 20 paid invoices, eager load fix

app/Models/Client.php

@@ -625,6 +625,29 @@ class Client extends EntityModel
             }
         }
     }
+
+    public function getUsuallyPaysIn() {
+        $paysIn = $this->invoices()
+                        ->with('payments')
+                        ->where('invoice_status_id', '=', INVOICE_STATUS_PAID)
+                        ->orderBy('invoice_date', 'desc')
+                        ->take(20)
+                        ->get()
+                        ->map(function ($item) {
+                            $payments = $item->payments()->orderBy('payment_date', 'asc')->get();
+                            $invoiceTotal = $item->amount;
+
+                            foreach($payments as $payment) {
+                                if($payment->amount < $invoiceTotal) {
+                                    $invoiceTotal -= $payment->amount;
+                                } elseif($payment->amount >= $invoiceTotal) {
+                                    return \Carbon::parse($item->invoice_date)->diffInDays($payment->payment_date);
+                                }
+                            }
+                        })->avg();
+
+        return $paysIn;
+    }
 }
 
 Client::creating(function ($client) {

app/Ninja/Presenters/ClientPresenter.php

@@ -46,6 +46,12 @@ class ClientPresenter extends EntityPresenter
         return $account->formatMoney($client->paid_to_date, $client);
     }
 
+    public function usuallyPaysIn() {
+        $avgDays = $this->entity->getUsuallyPaysIn();
+
+        return Utils::roundSignificant($avgDays) . ' ' . trans('texts.usually_pays_in_days');
+    }
+
     public function paymentTerms()
     {
         $client = $this->entity;

resources/lang/en/texts.php

@@ -3161,6 +3161,8 @@ $LANG = array(
     'failed_to_find_record' => 'Failed to find record',
     'valid_until_days' => 'Valid Until',
     'valid_until_days_help' => 'Automatically sets the <b>Valid Until</b> value on quotes to this many days in the future.  Leave blank to disable.',
+    'usually_pays_in_days' => 'Days',
+
 );
 
 return $LANG;

resources/views/clients/show.blade.php

@@ -212,6 +212,10 @@
                     <td style="text-align: right">{{ Utils::formatMoney($credit, $client->getCurrencyId()) }}</td>
                 </tr>
                 @endif
+                <tr>
+                    <td><small>Usually Pays In</small></td>
+                    <td style="text-align: right;">{{ $client->present()->usuallyPaysIn() }}</td>
+                </tr>
             </table>
             </h3>
         </div>