From ed81d35e38c22309c6ddfe5132fc849267c15ec9 Mon Sep 17 00:00:00 2001
From: David Beniamine <david.beniamine@tetras-libre.fr>
Date: Fri, 22 Mar 2019 09:06:44 +0100
Subject: [PATCH] Allow negative bills

---
 htdocs/takepos/invoice.php | 34 ++++++++++++++++++++++++++++++++++
 htdocs/takepos/pay.php     | 14 +++++++++-----
 2 files changed, 43 insertions(+), 5 deletions(-)

diff --git a/htdocs/takepos/invoice.php b/htdocs/takepos/invoice.php
index 45a65af3f94..f8a51849412 100644
--- a/htdocs/takepos/invoice.php
+++ b/htdocs/takepos/invoice.php
@@ -41,6 +41,20 @@ $idline = GETPOST('idline');
 $desc = GETPOST('desc', 'alpha');
 $pay = GETPOST('pay');
 
+/**
+ * Abort invoice creationg with a given error message
+ *
+ * @param   string  $message        Message explaining the error to the user
+ * @return	void
+ */
+function fail($message)
+{
+	header($_SERVER['SERVER_PROTOCOL'] . ' 500 Internal Server Error', true, 500);
+	die($message);
+}
+
+
+
 $placeid = 0;	// $placeid is id of invoice
 
 $invoice = new Facture($db);
@@ -62,6 +76,26 @@ if ($action == 'valid' && $user->rights->facture->creer)
 
 	$invoice = new Facture($db);
 	$invoice->fetch($placeid);
+	if($invoice->total_ttc<0){
+		$invoice->type= $invoice::TYPE_CREDIT_NOTE;
+		$sql="SELECT rowid FROM ".MAIN_DB_PREFIX."facture WHERE ";
+		$sql.="fk_soc = '".$invoice->socid."' ";
+		$sql.="AND type <> ".Facture::TYPE_CREDIT_NOTE." ";
+		$sql.="AND fk_statut >= ".$invoice::STATUS_VALIDATED." ";
+		$sql.="ORDER BY rowid DESC";
+		$resql = $db->query($sql);
+		if($resql){
+			$obj = $db->fetch_object($resql);
+			$fk_source=$obj->rowid;
+			if($fk_source == null){
+				fail($langs->transnoentitiesnoconv("NoPreviousBillForCustomer"));
+			}
+		}else{
+			fail($langs->transnoentitiesnoconv("NoPreviousBillForCustomer"));
+		}
+		$invoice->fk_facture_source=$fk_source;
+		$invoice->update($user);
+	}
 
 	if (! empty($conf->stock->enabled) and $conf->global->CASHDESK_NO_DECREASE_STOCK!="1") $invoice->validate($user, '', $conf->global->CASHDESK_ID_WAREHOUSE);
 	else $invoice->validate($user);
diff --git a/htdocs/takepos/pay.php b/htdocs/takepos/pay.php
index 33524b80a8c..7f8b300bb8b 100644
--- a/htdocs/takepos/pay.php
+++ b/htdocs/takepos/pay.php
@@ -66,7 +66,7 @@ $langs->loadLangs(array("main", "bills", "cashdesk"));
 	$('#change1').html(parseFloat(received).toFixed(2));
 	if (parseFloat(received)><?php echo $invoice->total_ttc;?>)
 		{
-		var change=parseFloat(parseFloat(received)-<?php echo $invoice->total_ttc;?>);
+		var change=parseFloat(parseFloat(received)-(<?php echo $invoice->total_ttc;?>));
 		$('#change2').html(change.toFixed(2));
 		}
 	}
@@ -79,10 +79,14 @@ $langs->loadLangs(array("main", "bills", "cashdesk"));
 	}
 
 	function Validate(payment){
-        parent.$("#poslines").load("invoice.php?place=<?php echo $place;?>&action=valid&pay="+payment, function() {
-            parent.$("#poslines").scrollTop(parent.$("#poslines")[0].scrollHeight);
-            parent.$.colorbox.close();
-        });
+		parent.$("#poslines").load("invoice.php?place=<?php echo $place;?>&action=valid&pay="+payment, function(response, status, xhr) {
+			if(status == "error"){
+				alert(response);
+			}else{
+				parent.$("#poslines").scrollTop(parent.$("#poslines")[0].scrollHeight);
+				parent.$.colorbox.close();
+			}
+		});
 
 	}
 </script>