[PATCH manager] sdn: fabrics: require at least one prefix

[Gabriel Goller <g.goller@proxmox.com>]

Prevent removing the last remaining fabric prefix by requiring either an
IPv4 prefix or an IPv6 prefix. Again this is enforced by the API, but
improve the UX by validating in the frontend.

Signed-off-by: Gabriel Goller <g.goller@proxmox.com>
---
 www/manager6/sdn/fabrics/FabricEdit.js | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/www/manager6/sdn/fabrics/FabricEdit.js b/www/manager6/sdn/fabrics/FabricEdit.js
index ddecbdc83df3..e9e0d1fa6286 100644
--- a/www/manager6/sdn/fabrics/FabricEdit.js
+++ b/www/manager6/sdn/fabrics/FabricEdit.js
@@ -67,6 +67,18 @@ Ext.define('PVE.sdn.Fabric.Fabric.Edit', {
                 vtype: 'IPCIDRAddress',
                 skipEmptyText: true,
                 deleteEmpty: !me.isCreate,
+                validator: function (value) {
+                    let ip6Prefix = this.up('window').down('[name=ip6_prefix]')?.getValue();
+                    if (!me.hasIpv6Support || value || ip6Prefix) {
+                        return true;
+                    }
+                    return gettext('Either IPv4 Prefix or IPv6 Prefix is required');
+                },
+                listeners: {
+                    change: function (field) {
+                        field.up('window').down('[name=ip6_prefix]')?.validate();
+                    },
+                },
             });
         }
 
@@ -90,10 +102,19 @@ Ext.define('PVE.sdn.Fabric.Fabric.Edit', {
                     vtype: 'IP6CIDRAddress',
                     skipEmptyText: true,
                     deleteEmpty: !me.isCreate,
+                    validator: function (value) {
+                        let ipPrefix = this.up('window').down('[name=ip_prefix]')?.getValue();
+                        if (value || ipPrefix) {
+                            return true;
+                        }
+                        return gettext('Either IPv4 Prefix or IPv6 Prefix is required');
+                    },
                     listeners: {
                         change: function (textbox, value) {
-                            let vm = textbox.up('window').getViewModel();
+                            let win = textbox.up('window');
+                            let vm = win.getViewModel();
                             vm.set('showIpv6ForwardingHint', !!value);
+                            win.down('[name=ip_prefix]')?.validate();
                         },
                     },
                 },
-- 
2.47.3