One frame for every tab: ribbons of actions, next steps as dialogs

Tabs are permanent and load on first show. The ribbon shows the current
tab's actions in workflow order, a small ribbon under it the view
controls; inapplicable actions are disabled with the reason as tooltip.
Starting a job stays on the tab; the Jobs tab reads (running), then shows
the end status. When a preview this session started ends, its log opens
with Run it (publish box) or Apply shadowing; Not now loses nothing, Run
it in Jobs reopens it. New hint moves to the Packages ribbon and acts on
the ticked packages without a hint.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 46 insertions, 0 deletions

diff --git a/sb_builder/ui.py b/sb_builder/ui.py
new file mode 100644
index 0000000..087d1a7
--- /dev/null
+++ b/sb_builder/ui.py
@@ -0,0 +1,46 @@
+# sb-builder - ribbon actions
+# Copyright (C) 2026 Danilo M. <danix@danix.xyz>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""Ribbon actions shared by the tabs (UI guidelines in AGENTS.md).
+
+Each tab owns two lists of QActions: `actions` for the main ribbon (what it
+does, in workflow order) and `view_actions` for the small one (selection and
+view controls). The main window shows the current tab's lists.
+"""
+
+from PyQt6.QtGui import QAction, QIcon
+from PyQt6.QtWidgets import QStyle
+
+
+def action(parent, text, icon, fallback, slot=None, checkable=False, shortcut=None):
+    """A ribbon action: freedesktop icon with a QStyle fallback."""
+    a = QAction(QIcon.fromTheme(icon, parent.style().standardIcon(fallback)), text, parent,
+                checkable=checkable)
+    if slot:
+        a.triggered.connect(lambda _checked=False: slot())
+    a.setData(shortcut)  # shown in the tooltip; the tab's QShortcut does the work
+    enable(a, None)
+    return a
+
+
+def enable(a, reason):
+    """Enable a, or disable it with reason as its tooltip: disabled, never hidden."""
+    a.setEnabled(not reason)
+    tip = a.text() + (f" ({a.data()})" if a.data() else "")
+    a.setToolTip(f"{tip}: {reason}" if reason else tip)
+
+
+SP = QStyle.StandardPixmap