feat(color): add CAD indexed color picker

src/app/mod.rs

@@ -599,6 +599,11 @@ pub(super) struct OpenCADStudio {
     // ── Floating panel windows ────────────────────────────────────────────
     /// Active `iced_aw` colour picker: destination plus its initial colour.
     color_pick_target: Option<(ColorPickTarget, AcadColor)>,
+    /// Visible page in the shared CAD colour picker.
+    color_picker_tab: ColorPickerTab,
+    /// Recently committed real colours, newest first.
+    /// ACI and True Color remain semantically distinct even when their RGB matches.
+    recent_colors: Vec<AcadColor>,
     /// The open in-canvas modal dialog, if any (Plan B: shared overlay instead
     /// of OS windows).
     active_modal: Option<ModalKind>,
@@ -1162,7 +1167,13 @@ pub struct SaveOutcome {
     refreshed_preview: Option<Option<acadrust::Preview>>,
     result: Result<(), crate::io::SaveFailure>,
 }
-
+/// Active page in the shared CAD colour picker.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub enum ColorPickerTab {
+    #[default]
+    Index,
+    TrueColor,
+}
 /// Where a colour chosen in the standalone palette window should be applied.
 #[derive(Debug, Clone)]
 pub enum ColorPickTarget {
@@ -2904,11 +2915,15 @@ pub enum Message {
     DsCenterMarkMode(String),
     /// Toggle the expanded colour palette for a DimStyle colour field.
     DsColorMore(DsField),
-    /// Open the `iced_aw` colour picker for a field and its current colour.
+    /// Open the shared CAD colour picker for a field and its current colour.
     OpenColorWindow(ColorPickTarget, AcadColor),
+    /// Switch between Index Color and True Color.
+    ColorPickerTabChanged(ColorPickerTab),
+    /// Change the pending colour without committing it yet.
+    ColorPickerColorChanged(AcadColor),
     /// Close the colour picker without choosing.
     CloseColorPicker,
-    /// A colour was chosen in the `iced_aw` picker.
+    /// Commit the colour chosen in the shared picker.
     ColorWindowPick(acadrust::types::Color),
     /// Set a block/linetype Handle field on the selected dim style from a
     /// dropdown of available block-records / linetypes (by name).
@@ -3127,6 +3142,8 @@ impl OpenCADStudio {
             last_point: None,
             main_window: None,
             color_pick_target: None,
+            color_picker_tab: ColorPickerTab::Index,
+            recent_colors: Vec::new(),
             active_modal: None,
             find_replace: FindReplaceState::default(),
             aec_drop_acknowledged: false,

src/app/update/mod.rs

@@ -7321,21 +7321,56 @@ impl OpenCADStudio {
             }
             Message::OpenColorWindow(target, color) => {
                 self.color_pick_target = Some((target, color));
+
+                // Always open the shared CAD colour picker on the indexed ACI page.
+                self.color_picker_tab = crate::app::ColorPickerTab::Index;
+                self.modal_offset = iced::Vector::ZERO;
                 self.ds_color_open = None;
                 self.mls_color_open = None;
                 self.ts_color_open = None;
                 self.ribbon.close_dropdown();
+
                 let i = self.active_tab;
                 self.tabs[i].properties.color_picker_open = false;
                 self.tabs[i].layers.color_picker_row = None;
-                // `color_pick_target.is_some()` drives the iced_aw overlay.
+
+                Task::none()
+            }
+
+            Message::ColorPickerTabChanged(tab) => {
+                self.color_picker_tab = tab;
+                Task::none()
+            }
+            Message::ColorPickerColorChanged(color) => {
+                if let Some((_, current)) = self.color_pick_target.as_mut() {
+                    *current = color;
+                }
                 Task::none()
             }
             Message::CloseColorPicker => {
                 self.color_pick_target = None;
                 Task::none()
             }
-            Message::ColorWindowPick(color) => self.on_color_window_pick(color),
+
+            Message::ColorWindowPick(color) => {
+                // Keep only real colours in the recent list. ByLayer / ByBlock / None
+                // are logical CAD states rather than reusable colours.
+                if matches!(
+                    &color,
+                    acadrust::types::Color::Index(_)
+                        | acadrust::types::Color::Rgb { .. }
+                ) {
+                    // No duplicates: selecting an existing colour moves it to the front.
+                    if let Some(pos) = self.recent_colors.iter().position(|c| c == &color) {
+                        self.recent_colors.remove(pos);
+                    }
+
+                    self.recent_colors.insert(0, color.clone());
+                    self.recent_colors.truncate(12);
+                }
+
+                self.on_color_window_pick(color)
+            }
             Message::DsSetHandle { field, value } => self.on_ds_set_handle(field, value),
         }
     }

src/app/view/mod.rs

@@ -1850,24 +1850,49 @@ impl OpenCADStudio {
             }
             None => composed.into(),
         };
-        // iced_aw owns the colour-picker overlay and keeps it above whichever
-        // application modal requested it.
+        // Shared CAD colour picker. Indexed ACI colours use OpenCADStudio's own
+        // dialog; True Color keeps the existing iced_aw gradient picker.
         if let Some((_, current)) = self.color_pick_target.as_ref() {
-            let initial = crate::ui::properties::acad_color_display(*current).0;
-            let modal_base =
-                crate::ui::modal::backdrop(base, Message::CloseColorPicker);
-            iced_aw::ColorPicker::new(
-                true,
-                initial,
-                modal_base,
-                Message::CloseColorPicker,
-                |color| {
-                    Message::ColorWindowPick(
-                        crate::ui::color_select::iced_to_acad_color(color),
+            match self.color_picker_tab {
+                super::ColorPickerTab::Index => {
+                    let content = crate::ui::color_select::index_color_page(
+                        *current,
+                        &self.recent_colors,
+                    );
+
+                    crate::ui::modal::modal(
+                        base,
+                        "Select Color",
+                        content,
+                        Message::CloseColorPicker,
+                        self.modal_offset,
+                        crate::ui::modal::ModalOptions::NOTICE,
                     )
-                },
-            )
-            .into()
+                }
+
+                super::ColorPickerTab::TrueColor => {
+                    let initial = crate::ui::properties::acad_color_display(*current).0;
+                    let modal_base =
+                        crate::ui::modal::backdrop(base, Message::CloseColorPicker);
+
+                    iced_aw::ColorPicker::new(
+                        true,
+                        initial,
+                        modal_base,
+
+                        // Cancel inside True Color returns to the indexed page instead
+                        // of closing the whole CAD colour picker.
+                        Message::ColorPickerTabChanged(super::ColorPickerTab::Index),
+
+                        |color| {
+                            Message::ColorWindowPick(
+                                crate::ui::color_select::iced_to_acad_color(color),
+                            )
+                        },
+                    )
+                    .into()
+                }
+            }
         } else {
             base
         }