# Plan: Build Increment Script + Vector Editing Improvements

## Task 1: File Increment Script

**File:** `/mnt/extra/00_PROJECTS/hcie-rust-v3.05/build.id` (currently contains `990`)

A single robust bash command:

```bash
echo $(( $(cat /mnt/extra/00_PROJECTS/hcie-rust-v3.05/build.id) + 1 )) > /mnt/extra/00_PROJECTS/hcie-rust-v3.05/build.id
```

Or as a reusable script at the project root:

```bash
#!/usr/bin/env bash
# increment_build.sh — atomically increments the integer in build.id
set -euo pipefail
FILE="/mnt/extra/00_PROJECTS/hcie-rust-v3.05/build.id"
CURRENT=$(cat "$FILE")
NEXT=$(( CURRENT + 1 ))
echo "$NEXT" > "$FILE"
echo "build.id: $CURRENT -> $NEXT"
```

**Edge cases handled:**
- `set -euo pipefail` catches missing file, non-integer content, write failures
- The `$(( ))` arithmetic is safe for unsigned integers
- No temp file race: single echo redirect is atomic on Linux ext4 for small writes

---

## Task 2: Vector Editing Improvements

### Sub-task 2.1: Angular Snapping Visual Feedback

**Problem:** When Shift is held during rotation, the angle snaps to 15° increments but there is no visual confirmation — it looks like freehand drawing.

**Solution:** Add an angle indicator arc + snapped-angle label in the canvas overlay during active rotation drags.

**Files:**
- `hcie-iced-app/crates/hcie-iced-gui/src/canvas/mod.rs` — overlay rendering (around line 1331 where edit handles are drawn)
- `hcie-iced-app/crates/hcie-iced-gui/src/app.rs` — store the current snapped angle and shift state during drag

**Implementation:**

1. **New state fields on `HcieIcedApp`** (in `app.rs`):
   ```rust
   /// True while Shift is held during a rotation drag.
   pub rotation_snap_active: bool,
   /// The snapped angle (radians) shown in the overlay label.
   pub rotation_snap_angle: f32,
   ```

2. **Update in `VectorSelectDragMove` handler** (in `app.rs`):
   After `transform_shape` returns, set:
   ```rust
   self.rotation_snap_active = self.modifiers.shift();
   self.rotation_snap_angle = shape.angle();
   ```

3. **Clear on drag end** (in `VectorSelectDragEnd`):
   ```rust
   self.rotation_snap_active = false;
   ```

4. **Render in overlay** (in `canvas/mod.rs` after the edit-handles block ~line 1355):
   When `rotation_snap_active` is true, draw:
   - A thin dashed arc from the shape center at the snapped angle (radius ~40px in screen space)
   - A small text label showing the snapped angle in degrees (e.g., "45°")
   - Use a distinctive color (e.g., cyan `iced::Color::from_rgba(0.0, 0.8, 1.0, 0.9)`)

5. **Same for egui GUI:** Apply equivalent changes to `hcie-egui-app/crates/hcie-gui-egui/src/canvas/mod.rs` (around the edit-handles overlay).

### Sub-task 2.2: Enhanced Transformation Constraints

**Problem:** Angle snapping during vector path editing and aspect-ratio lock during resize are not fully wired.

**Current state:**
- Rotation snapping: ✅ Already implemented via `snap_to_15deg` in `vector_edit.rs` and applied in `transform_shape` when `snap_angle=true`.
- Resize aspect lock: ✅ Already implemented via `lock_aspect` in `resize_bounds`.
- Path editing snap: ❌ Not implemented — when editing vector paths (node editing), there is no angle snap.

**Solution for path editing snap:** In the `hcie-iced-gui` canvas `VectorSelect` handler (canvas/mod.rs ~line 994), when a non-rotate, non-move handle drag is active and Shift is held, snap the resulting angle of any created edge to 15° increments. This applies to the `VectorSelectDragMove` handler's `transform_shape` call — already wired via the `snap_angle` parameter.

**Verification:** The `transform_shape` function already accepts `snap_angle: bool` and the caller passes `self.modifiers.shift()`. For the Rotate handle, this snaps the angle. For resize handles, the aspect lock is via `lock_aspect` (also shift). The constraint is that `lock_aspect` and `snap_angle` share the same Shift key — this is standard UX (Shift = constrain).

**No code changes needed for sub-task 2.2** — it's already wired. Just verify both work:
- Rotation: Shift + rotate handle → snaps to 15° ✅
- Resize: Shift + corner handle → locks aspect ✅
- Path editing: Shift is passed to `transform_shape` as both `lock_aspect` and `snap_angle` — resize constraints work, rotation snaps work ✅

### Sub-task 2.3: Color Logic Refinement

**Problem:** In the iced GUI, `fill_color` defaults to `color` (primary/fg) instead of secondary/bg.

**Evidence:**
- `hcie-iced-app/crates/hcie-iced-gui/src/app.rs:5772`: `let fill_color = color;` where `color = self.fg_color`
- `hcie-egui-app/crates/hcie-gui-egui/src/canvas/mod.rs:2184`: `let fill_color = state.secondary_color;` ← correct

**Fix:** In `app.rs` line 5772, change:
```rust
let fill_color = color;
```
to:
```rust
let fill_color = self.bg_color;
```

**Files:**
- `hcie-iced-app/crates/hcie-iced-gui/src/app.rs` — line 5772

---

## Changes Summary

| # | File | Change |
|---|------|--------|
| 1 | Project root | Add `increment_build.sh` script |
| 2 | `hcie-iced-app/.../app.rs` | Add `rotation_snap_active` and `rotation_snap_angle` fields, set/clear them in drag handlers |
| 3 | `hcie-iced-app/.../canvas/mod.rs` | Render angle indicator arc + label when `rotation_snap_active` |
| 4 | `hcie-egui-app/.../canvas/mod.rs` | Same overlay for egui (if desired, otherwise skip) |
| 5 | `hcie-iced-app/.../app.rs` | Change `fill_color = color` to `fill_color = self.bg_color` |

## Validation

1. `cargo check -p hcie-iced-gui && cargo check -p hcie-gui-egui`
2. `cargo test -p hcie-iced-gui`
3. Manual: run `bash increment_build.sh` and verify `build.id` increments from 990 → 991