From dc6f7246a3de8f5ff5ef89e8eed560a62aed7588 Mon Sep 17 00:00:00 2001
From: MarekSpodBiedry <73122968+MarekSpodBiedry@users.noreply.github.com>
Date: Mon, 12 Oct 2026 08:31:34 +0200
Subject: [PATCH] Page Setup opens on the sheet's saved margins (#524)

---
 crates/ui-egui/src/dialogs.rs              | 34 ++++++++++--------
 crates/ui-egui/tests/page_setup_margins.rs | 42 ++++++++++++++++++++++
 2 files changed, 62 insertions(+), 14 deletions(-)
 create mode 100644 crates/ui-egui/tests/page_setup_margins.rs

diff --git a/crates/ui-egui/src/dialogs.rs b/crates/ui-egui/src/dialogs.rs
index 5e859c6..776ac82 100644
--- a/crates/ui-egui/src/dialogs.rs
+++ b/crates/ui-egui/src/dialogs.rs
@@ -370,20 +370,26 @@ impl Dialog {
                 ],
                 json!({"header": "", "footer": "&CPage &P of &N"}),
             ),
-            "pageSetup" => Dialog::form(
-                "pageSetup",
-                "Page Setup",
-                "pageLayout.margins",
-                vec![
-                    Number { key: "left", label: "Left margin (in):" },
-                    Number { key: "right", label: "Right margin (in):" },
-                    Number { key: "top", label: "Top margin (in):" },
-                    Number { key: "bottom", label: "Bottom margin (in):" },
-                    Number { key: "header", label: "Header (in):" },
-                    Number { key: "footer", label: "Footer (in):" },
-                ],
-                json!({"left": 0.7, "right": 0.7, "top": 0.75, "bottom": 0.75, "header": 0.3, "footer": 0.3}),
-            ),
+            "pageSetup" => {
+                // Opens on the active sheet's saved margins, so OK without edits rewrites them unchanged.
+                let m = app.session.active().and_then(|d| d.wb.active()).map(|s| s.print.margins).unwrap_or([0.7, 0.7, 0.75, 0.75, 0.3, 0.3]);
+                // Round off f32 noise so the form shows 0.1, not 0.10000000149.
+                let [left, right, top, bottom, header, footer] = m.map(|v| (f64::from(v) * 1e4).round() / 1e4);
+                Dialog::form(
+                    "pageSetup",
+                    "Page Setup",
+                    "pageLayout.margins",
+                    vec![
+                        Number { key: "left", label: "Left margin (in):" },
+                        Number { key: "right", label: "Right margin (in):" },
+                        Number { key: "top", label: "Top margin (in):" },
+                        Number { key: "bottom", label: "Bottom margin (in):" },
+                        Number { key: "header", label: "Header (in):" },
+                        Number { key: "footer", label: "Footer (in):" },
+                    ],
+                    json!({"left": left, "right": right, "top": top, "bottom": bottom, "header": header, "footer": footer}),
+                )
+            }
             "textToColumns" => Dialog::form(
                 "textToColumns",
                 "Convert Text to Columns",
diff --git a/crates/ui-egui/tests/page_setup_margins.rs b/crates/ui-egui/tests/page_setup_margins.rs
new file mode 100644
index 0000000..c604d77
--- /dev/null
+++ b/crates/ui-egui/tests/page_setup_margins.rs
@@ -0,0 +1,42 @@
+//! Page Setup opens on the active sheet's saved margins, so OK without edits keeps them (issue #524).
+
+use gridcraft_engine::Session;
+use gridcraft_ui_egui::SheetApp;
+use serde_json::{Value, json};
+
+fn margins(app: &SheetApp) -> [f32; 6] {
+    app.session.active().and_then(|d| d.wb.active()).map(|s| s.print.margins).unwrap_or_default()
+}
+
+fn app_with_custom_margins() -> SheetApp {
+    let mut session = Session::new();
+    session.new_workbook();
+    let mut app = SheetApp::new(session, Default::default());
+    app.run("pageLayout.margins", json!({"left": 2.0, "right": 2.5, "top": 3.0, "bottom": 0.25, "header": 0.1, "footer": 0.2})).unwrap();
+    assert_eq!(margins(&app), [2.0, 2.5, 3.0, 0.25, 0.1, 0.2]);
+    app
+}
+
+#[test]
+fn page_setup_ok_without_edits_keeps_custom_margins() {
+    // Custom Margins / File > Page Setup open it bare; Print Titles opens it on the Sheet tab.
+    for params in [json!({}), json!({"tab": "Sheet"})] {
+        let mut app = app_with_custom_margins();
+        app.open_dialog("pageSetup", params);
+        let d = app.dialog.take().unwrap();
+        let shown = json!({"left": 2.0, "right": 2.5, "top": 3.0, "bottom": 0.25, "header": 0.1, "footer": 0.2});
+        assert_eq!(Value::Object(d.values.clone()), shown);
+        app.run("pageLayout.margins", Value::Object(d.values)).unwrap();
+        assert_eq!(margins(&app), [2.0, 2.5, 3.0, 0.25, 0.1, 0.2]);
+    }
+}
+
+#[test]
+fn page_setup_one_edited_field_keeps_the_other_margins() {
+    let mut app = app_with_custom_margins();
+    app.open_dialog("pageSetup", json!({}));
+    let mut d = app.dialog.take().unwrap();
+    d.values.insert("left".into(), json!(1.5));
+    app.run("pageLayout.margins", Value::Object(d.values)).unwrap();
+    assert_eq!(margins(&app), [1.5, 2.5, 3.0, 0.25, 0.1, 0.2]);
+}