Assign as payment - Differentiate between new and existing payments for 'Assign as payment'

When the selected transaction is already involved in a business payment,
propose to Edit the payment instead of Assigning it as a payment.
This is more informative and will help prevent users from accidentally replacing existing payments.

gnucash/gnome/gnc-plugin-business.c

@@ -319,6 +319,11 @@ static GtkActionEntry gnc_plugin_actions [] =
         N_("Assign the selected transaction as payment"),
         G_CALLBACK (gnc_plugin_business_cmd_assign_payment)
     },
+    {
+        "RegisterEditPayment", NULL, N_("Edit payment..."), NULL,
+        N_("Edit the payment this transaction is a part of"),
+        G_CALLBACK (gnc_plugin_business_cmd_assign_payment)
+    },
 };
 static guint gnc_plugin_n_actions = G_N_ELEMENTS (gnc_plugin_actions);
 
@@ -888,12 +893,18 @@ static const gchar *register_txn_actions[] =
     NULL
 };
 
+static const gchar *register_bus_txn_actions[] =
+{
+    "RegisterEditPayment",
+    NULL
+};
+
 static void
 gnc_plugin_business_update_menus (GncPluginPage *plugin_page)
 {
     GncMainWindow  *window;
     GtkActionGroup *action_group;
-    gboolean is_txn_register;
+    gboolean is_txn_register, is_bus_txn = FALSE;
 
     // We continue only if the current page is a plugin page
     if (!plugin_page || !GNC_IS_PLUGIN_PAGE(plugin_page))
@@ -905,11 +916,21 @@ gnc_plugin_business_update_menus (GncPluginPage *plugin_page)
     action_group = gnc_main_window_get_action_group(window, PLUGIN_ACTIONS_NAME);
     g_return_if_fail(GTK_IS_ACTION_GROUP(action_group));
 
+    if (is_txn_register)
+    {
+        Transaction *trans = gnc_plugin_page_register_get_current_txn (GNC_PLUGIN_PAGE_REGISTER(plugin_page));
+        if (xaccTransCountSplits(trans) > 0)
+            is_bus_txn = (xaccTransGetFirstAPARAcctSplit(trans, TRUE) != NULL);
+    }
     // Change visibility and also sensitivity according to whether we are in a txn register
     gnc_plugin_update_actions (action_group, register_txn_actions,
-                               "sensitive", is_txn_register);
+                               "sensitive", is_txn_register && !is_bus_txn);
     gnc_plugin_update_actions (action_group, register_txn_actions,
-                               "visible", is_txn_register);
+                               "visible", is_txn_register && !is_bus_txn);
+    gnc_plugin_update_actions (action_group, register_bus_txn_actions,
+                               "sensitive", is_txn_register && is_bus_txn);
+    gnc_plugin_update_actions (action_group, register_bus_txn_actions,
+                               "visible", is_txn_register && is_bus_txn);
 }
 
 
@@ -921,6 +942,12 @@ static void gnc_plugin_business_main_window_page_changed(GncMainWindow *window,
     update_inactive_actions(page);
 }
 
+
+void gnc_plugin_business_split_reg_ui_update (GncPluginPage *plugin_page)
+{
+    gnc_plugin_business_main_window_page_changed(NULL, plugin_page, NULL);
+}
+
 static void
 gnc_plugin_business_cmd_test_init_data (GtkAction *action,
                                         GncMainWindowActionData *data)
@@ -1011,6 +1038,7 @@ static const gchar* readonly_inactive_actions[] =
     "EmployeeProcessPaymentAction",
     "ToolbarNewInvoiceAction",
     "RegisterAssignPayment",
+    "RegisterEditPayment",
     NULL
 };
 

gnucash/gnome/gnc-plugin-business.h

@@ -66,4 +66,8 @@ void gnc_invoice_remind_bills_due_cb (void);
 void gnc_invoice_remind_invoices_due_cb (void);
 const char *gnc_plugin_business_get_invoice_printreport(void);
 
+
+void gnc_plugin_business_split_reg_ui_update (GncPluginPage *plugin_page);
+
+
 #endif /* __GNC_PLUGIN_BUSINESS_H */

gnucash/gnome/gnc-plugin-page-register.c

@@ -48,6 +48,7 @@
 #include "gnc-plugin-register.h"
 #include "gnc-plugin-menu-additions.h"
 #include "gnc-plugin-page-report.h"
+#include "gnc-plugin-business.h"
 
 #include "dialog-account.h"
 #include "dialog-find-account.h"
@@ -823,6 +824,17 @@ gnc_plugin_page_register_get_account (GncPluginPageRegister *page)
     return NULL;
 }
 
+Transaction *
+gnc_plugin_page_register_get_current_txn (GncPluginPageRegister *page)
+{
+    GncPluginPageRegisterPrivate *priv;
+    SplitRegister *reg;
+
+    priv = GNC_PLUGIN_PAGE_REGISTER_GET_PRIVATE(page);
+    reg = gnc_ledger_display_get_split_register(priv->ledger);
+    return gnc_split_register_get_current_trans(reg);
+}
+
 /* This is the list of actions which are switched inactive in a read-only book. */
 static const char* readonly_inactive_actions[] =
 {
@@ -949,10 +961,9 @@ gnc_plugin_page_register_ui_update (gpointer various, GncPluginPageRegister *pag
     uri = xaccTransGetAssociation(trans);
     action = gnc_plugin_page_get_action (GNC_PLUGIN_PAGE(page),
                                          "ExecAssociatedTransactionAction");
-    if (g_strcmp0 (uri, "") != 0 && g_strcmp0 (uri, NULL) != 0)
-        gtk_action_set_sensitive (GTK_ACTION(action), TRUE);
-    else
-        gtk_action_set_sensitive (GTK_ACTION(action), FALSE);
+    gtk_action_set_sensitive (GTK_ACTION(action), (uri && *uri));
+
+    gnc_plugin_business_split_reg_ui_update (GNC_PLUGIN_PAGE(page));
 
     /* If we are in a readonly book, make any modifying action inactive */
     if (qof_book_is_readonly(gnc_get_current_book()))

gnucash/gnome/gnc-plugin-page-register.h

@@ -153,6 +153,16 @@ gnc_plugin_page_register_get_query (GncPluginPage *plugin_page);
 Account *
 gnc_plugin_page_register_get_account (GncPluginPageRegister *page);
 
+/** Get the currently selected transaction in this register page.
+ *
+ *  @param page A "register" page.
+ *
+ *  @return The currently active transaction or NULL if there currently
+ *  is no currently selected.
+ */
+Transaction *
+gnc_plugin_page_register_get_current_txn (GncPluginPageRegister *page);
+
 G_END_DECLS
 /** @} */
 /** @} */

gnucash/gnome/ui/gnc-plugin-business-ui.xml

@@ -2,7 +2,8 @@
   <menubar>
     <menu name="Edit" action="EditAction">
       <placeholder name="EditSelectedPlaceholder">
-        <menuitem name="RegisterAssignPayment"       action="RegisterAssignPayment"/>
+          <menuitem name="RegisterAssignPayment"       action="RegisterAssignPayment"/>
+          <menuitem name="RegisterEditPayment"       action="RegisterEditPayment"/>
       </placeholder>
     </menu>
 
@@ -73,7 +74,8 @@
   <popup name="MainPopup" action="FakeToplevel">
     <!--separator name="PopupSep3"/-->
     <placeholder name="PopupPlaceholder3">
-      <menuitem name="RegisterAssignPayment"       action="RegisterAssignPayment"/>
+        <menuitem name="RegisterAssignPayment"       action="RegisterAssignPayment"/>
+        <menuitem name="RegisterEditPayment"       action="RegisterEditPayment"/>
     </placeholder>
   </popup>
 </ui>