FIELD: Field dialog, FIELD command and the ATTDEF field buttons

A Field dialog with the fields the application evaluates and the
reference format choices, FIELD placing a field as multi-line text, the
attribute definition dialogs' field buttons, field attachment on commit,
system variable / file size / regional date providers for field
evaluation, and the codec patch with the field authoring API.

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

src/app/command_driver/entity_commit.rs

@@ -226,8 +226,17 @@ impl OpenCADStudio {
                 self.tabs[i].scene.document.header.text_height = attribute.height;
             }
         }
+        // A field the committed text shows (FIELD, an ATTDEF Default from the
+        // Field dialog) is attached once the entity has its handle; the field
+        // objects are not part of the add delta, so the step is a snapshot.
+        let text_field = self.tabs[i].active_cmd.as_ref().and_then(|cmd| cmd.text_field());
         let label = self.history_label_from_active_cmd(i, "ENTITY");
-        let delta_safe = self.delta_add_safe(i, &entity);
+        let delta_safe = text_field.is_none() && self.delta_add_safe(i, &entity);
+        let field_value = match &entity {
+            codec::EntityType::MText(m) => m.value.clone(),
+            codec::EntityType::AttributeDefinition(a) => a.default_value.clone(),
+            _ => String::new(),
+        };
         let pending = self.begin_undo(i, label, 1, delta_safe);
         let is_associative_dimension = matches!(
             entity,
@@ -247,6 +256,14 @@ impl OpenCADStudio {
                     .attach_dimension_association(handle, sources);
             }
         }
+        if let (Some(handle), Some(field)) = (committed, text_field) {
+            crate::entities::field::set_text_field(
+                &mut self.tabs[i].scene.document,
+                handle,
+                Some(field),
+                &field_value,
+            );
+        }
         if let Some(handle) = committed {
             self.apply_continuous_constraints(i, &[handle]);
         }

src/app/commands/attdef.rs

@@ -54,6 +54,7 @@ impl OpenCADStudio {
                 if let Some(state) = self.attdef_dialog.as_mut() {
                     if let Some(value) = value {
                         state.default = value;
+                        state.field = None;
                     }
                     self.active_modal = Some(crate::app::ModalKind::AttDef);
                 }
@@ -134,6 +135,7 @@ impl OpenCADStudio {
             align_below: false,
             can_align_below: session.last.is_some(),
             error: None,
+            field: None,
         });
         drop(session);
         self.tabs[i].active_cmd = None;
@@ -154,6 +156,8 @@ impl OpenCADStudio {
             default: a.default_value.clone(),
             constant: a.flags.constant,
             error: None,
+            field: None,
+            field_changed: false,
         });
         self.active_modal = Some(crate::app::ModalKind::AttDefEdit);
     }
@@ -164,7 +168,15 @@ impl OpenCADStudio {
             match m {
                 AttdefDialogMsg::EditTag(v) => edit.tag = v,
                 AttdefDialogMsg::EditPrompt(v) => edit.prompt = v,
-                AttdefDialogMsg::EditDefault(v) => edit.default = v,
+                AttdefDialogMsg::EditDefault(v) => {
+                    edit.default = v;
+                    edit.field = None;
+                    edit.field_changed = true;
+                }
+                AttdefDialogMsg::EditInsertField => {
+                    self.active_modal = None;
+                    self.open_field_dialog(crate::ui::window::field_dialog::FieldTarget::AttdefEdit);
+                }
                 AttdefDialogMsg::Help => self.command_line.push_info(
                     crate::t!("Changes the tag, prompt and default value of an attribute definition.")
                         .as_ref(),
@@ -189,7 +201,15 @@ impl OpenCADStudio {
             AttdefDialogMsg::Annotative(v) => state.annotative = v,
             AttdefDialogMsg::Tag(v) => state.tag = v,
             AttdefDialogMsg::Prompt(v) => state.prompt = v,
-            AttdefDialogMsg::Default(v) => state.default = v,
+            AttdefDialogMsg::Default(v) => {
+                state.default = v;
+                state.field = None;
+            }
+            AttdefDialogMsg::InsertField => {
+                self.active_modal = None;
+                self.open_field_dialog(crate::ui::window::field_dialog::FieldTarget::AttdefDefault);
+                return Task::none();
+            }
             AttdefDialogMsg::Justify(c) => state.justify = c.0,
             AttdefDialogMsg::Style(v) => state.style = v,
             AttdefDialogMsg::Height(v) => state.height = v,
@@ -279,6 +299,7 @@ impl OpenCADStudio {
             oblique_angle: defaults.oblique_angle,
             boundary_width: width,
             line_spacing: 1.0,
+            field: state.field.clone(),
         };
         self.attdef_dialog = None;
         self.close_active_modal();
@@ -336,7 +357,7 @@ impl OpenCADStudio {
             self.tabs[i].scene.document.get_entity(state.handle),
             Some(codec::EntityType::AttributeDefinition(a))
                 if a.tag != attdef::normalize_tag(&state.tag) || a.prompt != state.prompt || a.default_value != state.default
-        );
+        ) || state.field_changed;
         if changed && !self.reject_locked_edit(i, state.handle) {
             self.push_undo_snapshot(i, "DDEDIT");
             if let Some(codec::EntityType::AttributeDefinition(a)) =
@@ -348,6 +369,14 @@ impl OpenCADStudio {
                 }
                 a.default_value = state.default.clone();
             }
+            if state.field_changed {
+                crate::entities::field::set_text_field(
+                    &mut self.tabs[i].scene.document,
+                    state.handle,
+                    state.field.clone(),
+                    &state.default,
+                );
+            }
             self.tabs[i]
                 .scene
                 .bump_entities(&[(state.handle, crate::scene::ChangeKind::Modified)]);

src/app/commands/field.rs

@@ -0,0 +1,206 @@
+//! FIELD and the Field dialog behind the ƒ buttons of the attribute
+//! definition dialogs.
+
+use crate::app::{Message, OpenCADStudio};
+use crate::command::CadCommand;
+use crate::modules::annotate::field_cmd::{FieldObjectPickCommand, FieldPlaceCommand};
+use crate::ui::window::field_dialog::{
+    fields_of, object_properties, FieldDialogMsg, FieldDialogState, FieldTarget, DATE_FORMATS,
+    NAMED_TYPES,
+};
+use iced::Task;
+
+impl OpenCADStudio {
+    pub(super) fn dispatch_field(&mut self, cmd: &str, i: usize) -> Option<Task<Message>> {
+        match cmd {
+            "FIELD" => {
+                self.open_field_dialog(FieldTarget::NewText);
+                Some(Task::none())
+            }
+            cmd if cmd == "_FIELD_OBJECT" || cmd.starts_with("_FIELD_OBJECT ") => {
+                let handle = cmd
+                    .split_whitespace()
+                    .nth(1)
+                    .and_then(|h| u64::from_str_radix(h, 16).ok())
+                    .map(codec::Handle::new);
+                if let Some(state) = self.field_dialog.as_mut() {
+                    if let Some(entity) = handle.and_then(|h| self.tabs[i].scene.document.get_entity(h)) {
+                        let props = object_properties(entity);
+                        state.object = Some((entity.common().handle, crate::t!(crate::entities::names::ui_name(entity)).into_owned()));
+                        state.object_prop = props.first().copied();
+                        state.object_props = props;
+                    }
+                    self.active_modal = Some(crate::app::ModalKind::Field);
+                    self.refresh_field_preview();
+                }
+                Some(Task::none())
+            }
+            _ => None,
+        }
+    }
+
+    /// Open the Field dialog for `target`.
+    pub(in crate::app) fn open_field_dialog(&mut self, target: FieldTarget) {
+        let mut state = FieldDialogState::new(target);
+        state.examples = DATE_FORMATS
+            .iter()
+            .map(|f| self.field_value(&format!("\\AcVar Date \\f \"{f}\""), &[]))
+            .collect();
+        self.field_dialog = Some(state);
+        self.fill_named_objects();
+        self.refresh_field_preview();
+        self.active_modal = Some(crate::app::ModalKind::Field);
+    }
+
+    fn field_value(&self, code: &str, objects: &[codec::Handle]) -> String {
+        crate::entities::field::evaluate(&self.tabs[self.active_tab].scene.document, code, objects, None)
+            .unwrap_or_else(|| "----".to_string())
+    }
+
+    fn refresh_field_preview(&mut self) {
+        let Some(state) = self.field_dialog.as_ref() else {
+            return;
+        };
+        let (code, objects) = state.code();
+        let preview = if state.complete() { self.field_value(&code, &objects) } else { String::new() };
+        if let Some(state) = self.field_dialog.as_mut() {
+            state.preview = preview;
+        }
+    }
+
+    /// The names of the chosen named-object type, sorted.
+    fn fill_named_objects(&mut self) {
+        let Some(state) = self.field_dialog.as_mut() else {
+            return;
+        };
+        let document = &self.tabs[self.active_tab].scene.document;
+        let mut names: Vec<(String, codec::Handle)> = match NAMED_TYPES[state.named_type] {
+            "Block" => document
+                .block_records
+                .iter()
+                .filter(|b| !b.name.starts_with('*'))
+                .map(|b| (b.name.clone(), b.handle))
+                .collect(),
+            "Dimstyle" => document.dim_styles.iter().map(|s| (s.name.clone(), s.handle)).collect(),
+            "Layer" => document.layers.iter().map(|l| (l.name.clone(), l.handle)).collect(),
+            "Linetype" => document.line_types.iter().map(|l| (l.name.clone(), l.handle)).collect(),
+            "Textstyle" => document
+                .text_styles
+                .iter()
+                .filter(|s| !s.name.is_empty())
+                .map(|s| (s.name.clone(), s.handle))
+                .collect(),
+            "View" => document.views.iter().map(|v| (v.name.clone(), v.handle)).collect(),
+            _ => Vec::new(),
+        };
+        names.sort_by_key(|(n, _)| n.to_lowercase());
+        state.named_names = names;
+        state.named = None;
+    }
+
+    pub(in crate::app) fn on_field_dialog(&mut self, m: FieldDialogMsg) -> Task<Message> {
+        let i = self.active_tab;
+        let Some(state) = self.field_dialog.as_mut() else {
+            return Task::none();
+        };
+        match m {
+            FieldDialogMsg::Category(c) => {
+                state.category = c;
+                let names = fields_of(c);
+                if !names.contains(&state.name) {
+                    state.name = names.first().copied().unwrap_or("Date");
+                }
+            }
+            FieldDialogMsg::Name(n) => {
+                state.name = n;
+                state.text_case = 0;
+            }
+            FieldDialogMsg::DateFormat(f) => state.date_format = f,
+            FieldDialogMsg::DateExample(k) => {
+                if let Some(f) = DATE_FORMATS.get(k) {
+                    state.date_format = f.to_string();
+                }
+            }
+            FieldDialogMsg::TextCase(k) => state.text_case = k,
+            FieldDialogMsg::FileParts(b) => state.file_parts = b,
+            FieldDialogMsg::FileExtension(v) => state.file_extension = v,
+            FieldDialogMsg::SizeUnit(k) => state.size_unit = k,
+            FieldDialogMsg::SysVar(v) => state.sysvar = v,
+            FieldDialogMsg::Diesel(v) => state.diesel = v,
+            FieldDialogMsg::NamedType(k) => {
+                state.named_type = k;
+                self.fill_named_objects();
+            }
+            FieldDialogMsg::Named(k) => state.named = Some(k),
+            FieldDialogMsg::ObjectProp(p) => state.object_prop = Some(p),
+            FieldDialogMsg::SelectObject => {
+                // The dialog waits while one object is picked.
+                self.active_modal = None;
+                let command = FieldObjectPickCommand;
+                self.command_line.push_info(&command.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(command));
+                return Task::none();
+            }
+            FieldDialogMsg::Help => self.command_line.push_info(
+                crate::t!("Inserts a field: text that updates from the drawing, the date or another source.").as_ref(),
+            ),
+            FieldDialogMsg::Ok => return self.field_dialog_ok(i),
+        }
+        self.refresh_field_preview();
+        Task::none()
+    }
+
+    fn field_dialog_ok(&mut self, i: usize) -> Task<Message> {
+        let Some(state) = self.field_dialog.take() else {
+            return Task::none();
+        };
+        let (code, objects) = state.code();
+        let value = state.preview.clone();
+        let field = Some((code, objects));
+        match state.target {
+            FieldTarget::NewText => {
+                self.close_active_modal();
+                let defaults =
+                    crate::scene::creation_style::current_text_defaults(&self.tabs[i].scene.document);
+                let command = FieldPlaceCommand::new(
+                    value,
+                    field.expect("set above"),
+                    defaults.style_name,
+                    defaults.height,
+                );
+                self.reset_command_start_state(i);
+                self.command_line.push_info(&command.prompt());
+                self.tabs[i].active_cmd = Some(Box::new(command));
+                self.push_ucs_to_cmd(i);
+                return self.focus_cmd_input();
+            }
+            FieldTarget::AttdefDefault => {
+                if let Some(dialog) = self.attdef_dialog.as_mut() {
+                    dialog.default = value;
+                    dialog.field = field;
+                }
+                self.active_modal = Some(crate::app::ModalKind::AttDef);
+            }
+            FieldTarget::AttdefEdit => {
+                if let Some(edit) = self.attdef_edit.as_mut() {
+                    edit.default = value;
+                    edit.field = field;
+                    edit.field_changed = true;
+                }
+                self.active_modal = Some(crate::app::ModalKind::AttDefEdit);
+            }
+        }
+        Task::none()
+    }
+
+    /// The dialogs a Field dialog was opened from come back when it closes.
+    pub(in crate::app) fn close_field_dialog(&mut self) {
+        let target = self.field_dialog.take().map(|s| s.target);
+        self.close_active_modal();
+        self.active_modal = match target {
+            Some(FieldTarget::AttdefDefault) if self.attdef_dialog.is_some() => Some(crate::app::ModalKind::AttDef),
+            Some(FieldTarget::AttdefEdit) if self.attdef_edit.is_some() => Some(crate::app::ModalKind::AttDefEdit),
+            _ => None,
+        };
+    }
+}

src/app/commands/mod.rs

@@ -5,6 +5,7 @@ use iced::Task;
 use std::path::PathBuf;
 
 mod attdef;
+mod field;
 mod blocks;
 mod xref_attach;
 mod dim;
@@ -282,6 +283,9 @@ impl OpenCADStudio {
         if let Some(t) = self.dispatch_attdef(cmd, i) {
             return Some(t);
         }
+        if let Some(t) = self.dispatch_field(cmd, i) {
+            return Some(t);
+        }
         if let Some(t) = self.dispatch_draw(cmd, i) {
             return Some(t);
         }

src/app/control/actions.rs

@@ -80,6 +80,7 @@ pub(super) const NAMES: &[&str] = &[
     "ribbon_dropdown",
     "dialog_ok",
     "attdef_dialog",
+    "field_dialog",
     "close_document",
     "toggle_properties",
     "toggle_layers",
@@ -870,6 +871,8 @@ impl OpenCADStudio {
                     "align_below" => M::AlignBelow(on),
                     "edit_value" => M::EditValue,
                     "dismiss" => M::DismissError,
+                    "insert_field" if editing => M::EditInsertField,
+                    "insert_field" => M::InsertField,
                     "x" => M::Coord(0, v.into()),
                     "y" => M::Coord(1, v.into()),
                     "z" => M::Coord(2, v.into()),
@@ -887,6 +890,35 @@ impl OpenCADStudio {
                     _ => return Err(failure("invalid_value", "Unknown attdef dialog field")),
                 })
             }
+            // One field of the open Field dialog: `category=<index>`, `name=Date`,
+            // `date=yyyy-MM-dd`, `case=0..4`, `file=1|2|3`, `ext=0|1`, `size=0..2`,
+            // `sysvar=dimscale`, `diesel=…`, `named_type=<index>`, `named=<index>`,
+            // `prop=Area`, `select_object`.
+            "field_dialog" => {
+                use crate::ui::window::field_dialog::{self as fd, FieldDialogMsg as F};
+                let value = string(req, "value")?;
+                let (key, v) = value.split_once('=').unwrap_or((value, ""));
+                let index = || v.parse::<usize>().map_err(|_| failure("invalid_value", "index expected"));
+                let known = |list: &[&'static str]| {
+                    list.iter().copied().find(|n| n.eq_ignore_ascii_case(v)).ok_or_else(|| failure("invalid_value", "unknown name"))
+                };
+                Message::FieldDialog(match key {
+                    "category" => F::Category(index()?),
+                    "name" => F::Name(known(&fd::fields_of(0))?),
+                    "date" => F::DateFormat(v.into()),
+                    "case" => F::TextCase(index()?),
+                    "file" => F::FileParts(v.parse::<u8>().map_err(|_| failure("invalid_value", "1|2|3"))?),
+                    "ext" => F::FileExtension(v == "1"),
+                    "size" => F::SizeUnit(index()?),
+                    "sysvar" => F::SysVar(v.into()),
+                    "diesel" => F::Diesel(v.into()),
+                    "named_type" => F::NamedType(index()?),
+                    "named" => F::Named(index()?),
+                    "prop" => F::ObjectProp(known(&["Area", "Center", "Circumference", "Diameter", "EndPoint", "Length", "Radius", "StartPoint"])?),
+                    "select_object" => F::SelectObject,
+                    _ => return Err(failure("invalid_value", "Unknown field dialog key")),
+                })
+            }
             "ribbon_dropdown" => Message::ToggleRibbonDropdown(string(req, "value")?.into()),
             "pdf_dialog_ok" => {
                 use crate::ui::window::pdf_dialogs::PdfDialogMsg;
@@ -913,6 +945,9 @@ impl OpenCADStudio {
                 Some(crate::app::ModalKind::AttDefEdit) => Message::AttdefDialog(
                     crate::ui::window::attdef_dialog::AttdefDialogMsg::EditOk,
                 ),
+                Some(crate::app::ModalKind::Field) => Message::FieldDialog(
+                    crate::ui::window::field_dialog::FieldDialogMsg::Ok,
+                ),
                 _ => return Err(failure("no_dialog", "No dialog with an OK button is open")),
             },
             "close_document" => Message::TabClose(self.tabs[self.active_tab].id),

src/app/mod.rs

@@ -501,6 +501,8 @@ pub(super) struct OpenCADStudio {
     /// ATTDEF dialog and Edit Attribute Definition dialog; `None` while closed.
     attdef_dialog: Option<crate::ui::window::attdef_dialog::AttdefDialogState>,
     attdef_edit: Option<crate::ui::window::attdef_dialog::AttdefEditState>,
+    /// Field dialog working copy; `None` while closed.
+    field_dialog: Option<crate::ui::window::field_dialog::FieldDialogState>,
     point_cloud_color_map: Option<crate::ui::window::pdf_dialogs::PointCloudColorMapState>,
     pc_section: Option<crate::ui::window::pdf_dialogs::PcSectionState>,
     underlay_layers: Option<crate::ui::window::pdf_dialogs::UnderlayLayersState>,
@@ -1922,6 +1924,7 @@ pub enum ModalKind {
     GeometricTolerance,
     AttDef,
     AttDefEdit,
+    Field,
     DraftingSettings,
     AutoConstrainSettings,
     LayerStateEditor,
@@ -3870,6 +3873,7 @@ pub enum Message {
     /// An edit in one of the PDF dialogs.
     PdfDialog(crate::ui::window::pdf_dialogs::PdfDialogMsg),
     AttdefDialog(crate::ui::window::attdef_dialog::AttdefDialogMsg),
+    FieldDialog(crate::ui::window::field_dialog::FieldDialogMsg),
     /// A click or search in the Point Cloud Manager.
     PcManager(crate::ui::window::pc_manager::PcManagerMsg),
     PdfImportPickResult(Result<(std::path::PathBuf, std::sync::Arc<Vec<u8>>), String>),
@@ -4065,6 +4069,7 @@ impl OpenCADStudio {
             point_cloud_attach: None,
             attdef_dialog: None,
             attdef_edit: None,
+            field_dialog: None,
             point_cloud_color_map: None,
             pc_section: None,
             underlay_layers: None,

src/app/update/mod.rs

@@ -1813,6 +1813,7 @@ impl OpenCADStudio {
 
             Message::PdfDialog(message) => self.update_pdf_dialog(message),
             Message::AttdefDialog(message) => self.on_attdef_dialog(message),
+            Message::FieldDialog(message) => self.on_field_dialog(message),
             Message::PcManager(message) => self.update_pc_manager(message),
             Message::RibbonSelectTab(idx) => {
                 self.ribbon.select(idx);
@@ -8503,6 +8504,10 @@ impl OpenCADStudio {
             }
 
             Message::CloseModal => {
+                if self.active_modal == Some(super::ModalKind::Field) {
+                    self.close_field_dialog();
+                    return Task::none();
+                }
                 if matches!(
                     self.active_modal,
                     Some(super::ModalKind::AttDef | super::ModalKind::AttDefEdit)

src/app/view/modal.rs

@@ -40,6 +40,7 @@ impl OpenCADStudio {
             Some(K::GeometricTolerance) => crate::t!("Geometric Tolerance").into_owned(),
             Some(K::AttDef) => crate::t!("Attribute Definition").into_owned(),
             Some(K::AttDefEdit) => crate::t!("Edit Attribute Definition").into_owned(),
+            Some(K::Field) => crate::t!("Field").into_owned(),
             Some(K::DraftingSettings) => crate::t!("Drafting Settings").into_owned(),
             Some(K::AutoConstrainSettings) => crate::t!("Constraint Settings").into_owned(),
             Some(K::LayerStateEditor) => crate::tr!("modal", "edit-layer-state"),
@@ -578,6 +579,10 @@ impl OpenCADStudio {
                 let state = self.attdef_dialog.as_ref()?;
                 sized_flow(ex, 720, 520, |flow| crate::ui::window::attdef_dialog::view(state, flow))
             }
+            super::super::ModalKind::Field => {
+                let state = self.field_dialog.as_ref()?;
+                sized_flow(ex, 760, 660, |flow| crate::ui::window::field_dialog::view(state, flow))
+            }
             super::super::ModalKind::AttDefEdit => {
                 let state = self.attdef_edit.as_ref()?;
                 sized_flow(ex, 460, 220, |flow| crate::ui::window::attdef_dialog::view_edit(state, flow))