feat: REFEDIT / REFCLOSE — in-place block reference editing

REFEDIT picks an INSERT, extracts the block entities into model space
with the INSERT transform applied (translate + rotate + uniform scale),
and enters an editing session.  Any normal modify command works on the
temporary entities.

REFCLOSE SAVE applies the inverse transform, replaces the block
definition, and rebuilds all derived caches (hatch/image/mesh), so
every INSERT of that block reflects the edits immediately.
REFCLOSE DISCARD removes the temp entities without changing the block.

Non-uniform-scale inserts are rejected with an error message.
RefEditSession is stored on DocumentTab; undo snapshots bracket the
begin and close operations.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

src/modules/home/modify/mod.rs

@@ -18,4 +18,5 @@ pub mod stretch;
 pub mod translate;
 pub mod spline_ops;
 pub mod splinedit;
+pub mod refedit;
 pub mod trim;

src/modules/home/modify/refedit.rs

@@ -0,0 +1,210 @@
+// REFEDIT — in-place block reference editing.
+//
+// Workflow:
+//   1. REFEDIT: user picks an INSERT entity.
+//   2. The block's entities are copied into model space with the INSERT
+//      transform applied (translate + rotate + uniform scale).
+//   3. The user edits them with normal commands (MOVE, COPY, DELETE, …).
+//   4. REFCLOSE SAVE: temp entities are inverse-transformed back into the
+//      block definition; all INSERT references auto-update.
+//      REFCLOSE DISCARD: temp entities are removed, block unchanged.
+//
+// Limitation: non-uniform scale inserts (x_scale ≠ y_scale) are rejected
+// with an error message — full matrix inversion for those cases would
+// require per-entity matrix transforms not yet in EntityTransform.
+
+use acadrust::{EntityType, Handle};
+use glam::Vec3;
+
+use crate::command::{CadCommand, CmdResult};
+
+// ── Session state (held in DocumentTab) ───────────────────────────────────
+
+/// Active REFEDIT session.  Lives in `DocumentTab::refedit_session`.
+#[derive(Debug, Clone)]
+pub struct RefEditSession {
+    /// The INSERT entity being edited.
+    pub insert_handle: Handle,
+    /// Name of the block being edited.
+    pub block_name: String,
+    /// Handle of the block record (owns the block entities).
+    pub br_handle: Handle,
+    /// Handles of the temporary model-space entities added for editing.
+    pub temp_handles: Vec<Handle>,
+    // ── INSERT transform (needed for inverse on SAVE) ──────────────────
+    pub insert_x: f64,
+    pub insert_y: f64,
+    pub insert_z: f64,
+    /// Rotation in degrees (stored as degrees in acadrust).
+    pub rotation_deg: f64,
+    /// Uniform scale factor (same for X/Y/Z after validation).
+    pub scale: f64,
+}
+
+// ── REFEDIT pick command ───────────────────────────────────────────────────
+
+/// Step 1: wait for the user to pick a single INSERT entity.
+pub struct RefEditPickCommand;
+
+impl RefEditPickCommand {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
+impl CadCommand for RefEditPickCommand {
+    fn name(&self) -> &'static str {
+        "REFEDIT"
+    }
+    fn prompt(&self) -> String {
+        "REFEDIT  Select block reference to edit:".into()
+    }
+
+    fn needs_entity_pick(&self) -> bool {
+        true
+    }
+
+    fn on_entity_pick(&mut self, handle: Handle, _pt: Vec3) -> CmdResult {
+        if handle.is_null() {
+            return CmdResult::NeedPoint;
+        }
+        // Signal the host to enter the editing session for this handle.
+        // We reuse Relaunch("REFEDIT_BEGIN:<handle>") as a convention.
+        CmdResult::Relaunch(
+            format!("REFEDIT_BEGIN:{}", handle.value()),
+            vec![handle],
+        )
+    }
+
+    fn on_point(&mut self, _pt: Vec3) -> CmdResult {
+        CmdResult::NeedPoint
+    }
+    fn on_enter(&mut self) -> CmdResult {
+        CmdResult::Cancel
+    }
+}
+
+// ── REFCLOSE command ───────────────────────────────────────────────────────
+
+/// Step 4: prompt for SAVE or DISCARD.
+pub struct RefCloseCommand;
+
+impl RefCloseCommand {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
+impl CadCommand for RefCloseCommand {
+    fn name(&self) -> &'static str {
+        "REFCLOSE"
+    }
+    fn prompt(&self) -> String {
+        "REFCLOSE  [Save/Discard] <Save>:".into()
+    }
+    fn wants_text_input(&self) -> bool {
+        true
+    }
+    fn on_text_input(&mut self, text: &str) -> Option<CmdResult> {
+        let t = text.trim().to_uppercase();
+        let save = t.is_empty() || t == "S" || t == "SAVE";
+        let discard = t == "D" || t == "DISCARD";
+        if save {
+            Some(CmdResult::Relaunch("REFCLOSE_SAVE".into(), vec![]))
+        } else if discard {
+            Some(CmdResult::Relaunch("REFCLOSE_DISCARD".into(), vec![]))
+        } else {
+            Some(CmdResult::NeedPoint) // re-prompt
+        }
+    }
+    fn on_enter(&mut self) -> CmdResult {
+        // Default: SAVE
+        CmdResult::Relaunch("REFCLOSE_SAVE".into(), vec![])
+    }
+    fn on_point(&mut self, _pt: Vec3) -> CmdResult {
+        CmdResult::NeedPoint
+    }
+}
+
+// ── Geometry helpers ───────────────────────────────────────────────────────
+
+/// Apply the INSERT's forward transform to a block-local entity so it
+/// appears at its correct world-space position.
+/// Order: scale → rotate (around origin) → translate.
+pub fn apply_insert_transform(entity: &mut EntityType, session: &RefEditSession) {
+    use crate::command::EntityTransform;
+    use crate::scene::dispatch;
+
+    let origin = Vec3::ZERO;
+
+    // 1. Uniform scale (if not 1.0)
+    if (session.scale - 1.0).abs() > 1e-10 {
+        dispatch::apply_transform(
+            entity,
+            &EntityTransform::Scale { center: origin, factor: session.scale as f32 },
+        );
+    }
+
+    // 2. Rotate around origin
+    if session.rotation_deg.abs() > 1e-10 {
+        dispatch::apply_transform(
+            entity,
+            &EntityTransform::Rotate {
+                center: origin,
+                angle_rad: session.rotation_deg.to_radians() as f32,
+            },
+        );
+    }
+
+    // 3. Translate to insert position
+    dispatch::apply_transform(
+        entity,
+        &EntityTransform::Translate(Vec3::new(
+            session.insert_x as f32,
+            session.insert_y as f32,
+            session.insert_z as f32,
+        )),
+    );
+}
+
+/// Apply the INSERT's inverse transform to a world-space entity to bring it
+/// back to block-local coordinates.
+/// Order: un-translate → un-rotate → un-scale.
+pub fn apply_insert_inverse_transform(entity: &mut EntityType, session: &RefEditSession) {
+    use crate::command::EntityTransform;
+    use crate::scene::dispatch;
+
+    let origin = Vec3::ZERO;
+
+    // 1. Un-translate
+    dispatch::apply_transform(
+        entity,
+        &EntityTransform::Translate(Vec3::new(
+            -session.insert_x as f32,
+            -session.insert_y as f32,
+            -session.insert_z as f32,
+        )),
+    );
+
+    // 2. Un-rotate
+    if session.rotation_deg.abs() > 1e-10 {
+        dispatch::apply_transform(
+            entity,
+            &EntityTransform::Rotate {
+                center: origin,
+                angle_rad: -session.rotation_deg.to_radians() as f32,
+            },
+        );
+    }
+
+    // 3. Un-scale
+    if (session.scale - 1.0).abs() > 1e-10 && session.scale.abs() > 1e-12 {
+        dispatch::apply_transform(
+            entity,
+            &EntityTransform::Scale {
+                center: origin,
+                factor: (1.0 / session.scale) as f32,
+            },
+        );
+    }
+}