fix(plotstyle): validate and stage table edits

Validate plot-style color, lineweight, and screening fields atomically and report invalid input without changing the table. Keep successful Save and Save As edits as the close baseline; discard edits made after that baseline when the panel closes. CTB files are app-level state, so these changes do not dirty the drawing or create drawing undo entries.

test: invalid screening retains prior value and reports error

test: invalid color retains prior value and reports error

test: invalid lineweight retains prior value and reports error

test: closing panel discards unsaved edits

test: closing panel keeps values from saved baseline

src/app/mod.rs

@@ -1364,6 +1364,9 @@ pub(super) struct OpenCADStudio {
     // ── Plot Style Table ──────────────────────────────────────────────────
     /// Currently loaded CTB/STB table (None = no override).
     active_plot_style: Option<crate::io::plot_style::PlotStyleTable>,
+    /// Table state at Plot Style editor open / last save. Edits preview live,
+    /// but closing the editor restores this baseline until Save succeeds.
+    pub(super) plotstyle_panel_baseline: Option<Option<crate::io::plot_style::PlotStyleTable>>,
 
     // ── MLineStyle Dialog ─────────────────────────────────────────────────
     mlstyle_selected: String,
@@ -5107,6 +5110,7 @@ impl OpenCADStudio {
                 )
             })
             .ok(),
+            plotstyle_panel_baseline: None,
             // Color scheme (default: Oxocarbon)
             active_theme: Theme::Oxocarbon,
             ui_theme: config::UiThemeConfig::default(),

src/app/update/file.rs

@@ -7469,46 +7469,85 @@ impl OpenCADStudio {
         })
     }
 
+    pub(super) fn commit_plotstyle_panel_baseline(&mut self) {
+        if self.plotstyle_panel_baseline.is_some() {
+            self.plotstyle_panel_baseline = Some(self.active_plot_style.clone());
+        }
+    }
+
     pub(super) fn on_plot_style_panel_apply(&mut self) -> Task<Message> {
-        let aci = self.plotstyle_panel_aci as usize;
+        let color_text = self.ps_color_buf.trim();
-        if let Some(table) = self.active_plot_style.as_mut() {
+        let color = if color_text.is_empty() {
-            if let Some(entry) = table.aci_entries.get_mut(aci) {
+            None
-                // Parse color.
-                let color_str = self.ps_color_buf.trim();
-                if color_str.is_empty() {
-                    entry.color = None;
-                } else if color_str.starts_with('#') && color_str.len() == 7 {
-                    let r = u8::from_str_radix(&color_str[1..3], 16).unwrap_or(0);
-                    let g = u8::from_str_radix(&color_str[3..5], 16).unwrap_or(0);
-                    let b = u8::from_str_radix(&color_str[5..7], 16).unwrap_or(0);
-                    entry.color = Some([r, g, b]);
-                }
-                if let Ok(lw) = self.ps_lineweight_buf.trim().parse::<u8>() {
-                    entry.lineweight = lw;
-                }
-                if let Ok(sc) = self.ps_screening_buf.trim().parse::<u8>() {
-                    entry.screening = sc.min(100);
-                }
-            }
         } else {
-            // No table loaded: create an identity table and apply.
+            let Some(hex) = color_text.strip_prefix('#').filter(|hex| hex.len() == 6) else {
-            let mut table = crate::io::plot_style::PlotStyleTable::identity("Custom.ctb");
+                self.command_line.push_error(
-            if let Some(entry) = table.aci_entries.get_mut(aci) {
+                    crate::t!("Enter a plot color as #RRGGBB, or clear it to use object color.")
-                let color_str = self.ps_color_buf.trim();
+                        .as_ref(),
-                if color_str.starts_with('#') && color_str.len() == 7 {
+                );
-                    let r = u8::from_str_radix(&color_str[1..3], 16).unwrap_or(0);
+                return Task::none();
-                    let g = u8::from_str_radix(&color_str[3..5], 16).unwrap_or(0);
+            };
-                    let b = u8::from_str_radix(&color_str[5..7], 16).unwrap_or(0);
+            let Ok(rgb) = u32::from_str_radix(hex, 16) else {
-                    entry.color = Some([r, g, b]);
+                self.command_line.push_error(
-                }
+                    crate::t!("Enter a plot color as #RRGGBB, or clear it to use object color.")
-                if let Ok(lw) = self.ps_lineweight_buf.trim().parse::<u8>() {
+                        .as_ref(),
-                    entry.lineweight = lw;
+                );
-                }
+                return Task::none();
-                if let Ok(sc) = self.ps_screening_buf.trim().parse::<u8>() {
+            };
-                    entry.screening = sc.min(100);
+            Some([
-                }
+                ((rgb >> 16) & 0xFF) as u8,
-            }
+                ((rgb >> 8) & 0xFF) as u8,
-            self.active_plot_style = Some(table);
+                (rgb & 0xFF) as u8,
+            ])
+        };
+
+        let Ok(lineweight) = self.ps_lineweight_buf.trim().parse::<u8>() else {
+            self.command_line
+                .push_error(crate::t!("Choose a valid plot lineweight.").as_ref());
+            return Task::none();
+        };
+        if lineweight != 255 && lineweight as usize >= crate::io::plot_style::LW_TABLE.len() {
+            self.command_line
+                .push_error(crate::t!("Choose a valid plot lineweight.").as_ref());
+            return Task::none();
+        }
+
+        let Ok(screening) = self.ps_screening_buf.trim().parse::<u8>() else {
+            self.command_line.push_error(
+                crate::t!("Screening must be a whole number from 0 to 100.").as_ref(),
+            );
+            return Task::none();
+        };
+        if screening > 100 {
+            self.command_line.push_error(
+                crate::t!("Screening must be a whole number from 0 to 100.").as_ref(),
+            );
+            return Task::none();
+        }
+
+        let aci = self.plotstyle_panel_aci as usize;
+        if aci == 0 {
+            self.command_line
+                .push_error(crate::t!("Select a plot style color index from 1 to 255.").as_ref());
+            return Task::none();
+        }
+
+        let created = self.active_plot_style.is_none();
+        if created {
+            self.active_plot_style = Some(crate::io::plot_style::PlotStyleTable::identity(
+                "Custom.ctb",
+            ));
+        }
+        if let Some(entry) = self
+            .active_plot_style
+            .as_mut()
+            .and_then(|table| table.aci_entries.get_mut(aci))
+        {
+            entry.color = color;
+            entry.lineweight = lineweight;
+            entry.screening = screening;
+        }
+        if created {
             self.command_line
                 .push_output(crate::tf!("Created new CTB table, ACI {aci} updated.").as_ref());
         }
@@ -9084,6 +9123,115 @@ mod background_task_tests {
     }
 }
 
+#[cfg(test)]
+mod plot_style_panel_tests {
+    use crate::app::{Message, OpenCADStudio};
+
+    fn app_with_test_table() -> OpenCADStudio {
+        let mut app = OpenCADStudio::new_for_test();
+        let mut table = crate::io::plot_style::PlotStyleTable::identity("Test.ctb");
+        table.aci_entries[1].screening = 65;
+        app.plot_dialog.style_name = table.name.clone();
+        app.active_plot_style = Some(table);
+        app
+    }
+
+    #[test]
+    fn invalid_screening_keeps_last_valid_value_and_reports_error() {
+        let mut app = app_with_test_table();
+
+        let old_error_revision = app.command_line.error_revision;
+        let _ = app.update(Message::PlotStylePanelScreenBuf("200".into()));
+
+        assert_eq!(
+            app.active_plot_style.as_ref().unwrap().aci_entries[1].screening,
+            65,
+            "invalid input must not overwrite the last valid screening"
+        );
+        assert!(
+            app.command_line.error_revision > old_error_revision,
+            "invalid input should report feedback on the command line"
+        );
+    }
+
+    #[test]
+    fn invalid_color_is_reported_without_changing_the_entry() {
+        let mut app = app_with_test_table();
+        let entry = &mut app.active_plot_style.as_mut().unwrap().aci_entries[1];
+        entry.color = Some([12, 34, 56]);
+        entry.lineweight = 4;
+        app.ps_lineweight_buf = "5".into();
+        app.ps_screening_buf = "70".into();
+        let old_error_revision = app.command_line.error_revision;
+
+        let _ = app.update(Message::PlotStylePanelColorBuf("#fff".into()));
+
+        let entry = &app.active_plot_style.as_ref().unwrap().aci_entries[1];
+        assert_eq!(entry.color, Some([12, 34, 56]));
+        assert_eq!(entry.lineweight, 4);
+        assert_eq!(entry.screening, 65);
+        assert!(app.command_line.error_revision > old_error_revision);
+    }
+
+    #[test]
+    fn invalid_lineweight_is_reported_without_changing_the_entry() {
+        let mut app = app_with_test_table();
+        let entry = &mut app.active_plot_style.as_mut().unwrap().aci_entries[1];
+        entry.color = Some([12, 34, 56]);
+        entry.lineweight = 4;
+        app.ps_color_buf = "#010203".into();
+        app.ps_lineweight_buf = "200".into();
+        app.ps_screening_buf = "70".into();
+        let old_error_revision = app.command_line.error_revision;
+
+        let _ = app.update(Message::PlotStylePanelLwBuf("200".into()));
+
+        let entry = &app.active_plot_style.as_ref().unwrap().aci_entries[1];
+        assert_eq!(entry.color, Some([12, 34, 56]));
+        assert_eq!(entry.lineweight, 4);
+        assert_eq!(entry.screening, 65);
+        assert!(app.command_line.error_revision > old_error_revision);
+    }
+
+    #[test]
+    fn closing_plot_style_panel_restores_unsaved_table_edits() {
+        let mut app = app_with_test_table();
+        let _ = app.update(Message::PlotStylePanelOpen);
+
+        let _ = app.update(Message::PlotStylePanelScreenBuf("72".into()));
+        assert_eq!(
+            app.active_plot_style.as_ref().unwrap().aci_entries[1].screening,
+            72
+        );
+
+        app.close_active_modal();
+
+        assert_eq!(
+            app.active_plot_style.as_ref().unwrap().aci_entries[1].screening,
+            65,
+            "closing without saving should restore the table from editor open"
+        );
+    }
+
+    #[test]
+    fn closing_after_save_keeps_saved_table_and_discards_later_edits() {
+        let mut app = app_with_test_table();
+        let _ = app.update(Message::PlotStylePanelOpen);
+
+        let _ = app.update(Message::PlotStylePanelScreenBuf("72".into()));
+        app.commit_plotstyle_panel_baseline();
+
+        let _ = app.update(Message::PlotStylePanelScreenBuf("80".into()));
+        app.close_active_modal();
+
+        assert_eq!(
+            app.active_plot_style.as_ref().unwrap().aci_entries[1].screening,
+            72,
+            "closing should keep the last successfully saved table state"
+        );
+    }
+}
+
 impl OpenCADStudio {
     /// Web: one warning lists every unresolved xref and the way to fix it —
     /// dropping the files on the page registers their bytes, and reopening

src/app/update/mod.rs

@@ -159,6 +159,9 @@ impl OpenCADStudio {
             }
         }
         if self.active_modal == Some(Plotstyle) {
+            if let Some(baseline) = self.plotstyle_panel_baseline.take() {
+                self.active_plot_style = baseline;
+            }
             if let Some((plot_offset, plot_resize)) = self.plotstyle_parent_plot_geometry.take() {
                 self.active_modal = Some(Plot);
 
@@ -11245,6 +11248,9 @@ impl OpenCADStudio {
                     .as_ref(),
                 );
                 self.active_plot_style = Some(table);
+                if self.active_modal == Some(super::ModalKind::Plotstyle) {
+                    self.plotstyle_panel_baseline = Some(self.active_plot_style.clone());
+                }
                 self.plot_dialog.plot_styles = crate::io::plot_style::available_ctb_names();
                 Task::none()
             }
@@ -11261,6 +11267,7 @@ impl OpenCADStudio {
                 self.active_plot_style = None;
                 self.plot_dialog.style_name.clear();
                 self.plot_dialog.style_missing = false;
+                self.commit_plotstyle_panel_baseline();
                 self.command_line
                     .push_output(crate::t!("Plot style table cleared.").as_ref());
                 Task::none()
@@ -11329,6 +11336,7 @@ impl OpenCADStudio {
                 }
 
                 self.active_modal = Some(super::ModalKind::Plotstyle);
+                self.plotstyle_panel_baseline = Some(self.active_plot_style.clone());
                 Task::none()
             }
             Message::PlotStylePanelClose => {
@@ -11404,6 +11412,7 @@ impl OpenCADStudio {
                             self.tabs[self.active_tab]
                                 .scene
                                 .invalidate_display_plot_style();
+                            self.commit_plotstyle_panel_baseline();
 
                             self.command_line.push_output(
                                 crate::tf!("Plot style table saved to \"{}\".", path.display())
@@ -11455,6 +11464,7 @@ impl OpenCADStudio {
                             self.tabs[self.active_tab]
                                 .scene
                                 .invalidate_display_plot_style();
+                            self.commit_plotstyle_panel_baseline();
                             self.command_line.push_output(
                                 crate::tf!("Plot style table saved to \"{}\".", path.display())
                                     .as_ref(),