undo/redo - 50%

src/undo.rs

@@ -0,0 +1,123 @@
+use bevy::prelude::*;
+
+use crate::{CreateShape, ShapeData};
+
+#[derive(Debug, Clone)]
+pub enum UndoItem {
+    Base,
+    CreateShape { entity: Entity },
+    MoveDot { shape_data: Entity, dot: Entity, from: Vec2, to: Vec2 },
+    MoveShape { shape: Entity, from: Vec2, to: Vec2 },
+    Rotate { entity: Entity, from: f32, to: f32 },
+    NameChange { entity: Entity, from: String },
+    DeleteShape { name: String, shape: CreateShape, edges: Vec<Vec2>, transform: Transform, color: Color, note: String },
+}
+pub struct UndoStack {
+    items: Vec<UndoItem>,
+    current_action: usize,
+    last_valid: usize,
+}
+
+impl Default for UndoStack {
+    fn default() -> Self {
+        Self { items: [UndoItem::Base].to_vec(), current_action: 0, last_valid: 0 }
+    }
+}
+impl UndoStack {
+    pub fn push(&mut self, item: UndoItem) {
+        bevy::log::info!("PUSHING: {:?}", item);
+        if self.current_action < self.items.len() - 1 {
+            // We need to do a "semi push"
+            self.current_action += 1;
+            self.items[self.current_action] = item;
+        }
+        else {
+            // We push a completly new item and might need more space!
+            self.items.push(item);
+            self.current_action = self.items.len() - 1;
+        }
+        self.last_valid = self.current_action;
+    }
+    /// Pop the last item in the stack
+    pub fn pop(&mut self) -> Option<&mut UndoItem> {
+        // If this happens we are clearly into invalid territory
+        assert!(self.current_action < self.items.len());
+        if self.current_action > 0 {
+            let item = &mut self.items[self.current_action];
+            self.current_action -= 1;
+            Some(item)
+        }
+        else {
+            None
+        }
+    }
+    // If exists, "unpops" the last popped item
+    pub fn unpop(&mut self) -> Option<&mut UndoItem> {
+        if self.current_action < self.last_valid {
+            self.current_action += 1;
+            let item = &mut self.items[self.current_action];
+            Some(item)
+        }
+        else {
+            None
+        }
+    }
+}
+
+pub fn undo_redo_sys(
+    mut coms: Commands,
+    mut stack: ResMut<UndoStack>,
+    keyboard: Res<Input<KeyCode>>,
+    mut shapes: Query<&mut ShapeData>,
+    mut transforms: Query<&mut Transform>,
+) {
+    if keyboard.just_pressed(KeyCode::Z) && keyboard.pressed(KeyCode::LControl) {
+        let item = if keyboard.pressed(KeyCode::LShift) { stack.unpop() } else { stack.pop() };
+        if let Some(item) = item {
+            match item {
+                UndoItem::Base => bevy::log::error!("POP/UNPOP: Got UndoItem::Base as a result!"),
+                UndoItem::CreateShape { entity } => {
+                    bevy::log::error!("NOT IMPLEMENTED : CreateShape");
+                },
+                UndoItem::MoveDot { shape_data, dot, from, to } => {
+                    bevy::log::error!("NOT IMPLEMENTED : MoveDot");
+                },
+                UndoItem::MoveShape { shape, from, to } => {
+                    if let Ok(mut t) = transforms.get_mut(*shape) {
+                        t.translation = from.extend(t.translation.z);
+                    }
+                    let t = *from;
+                    *from = *to;
+                    *to = t;
+                },
+                UndoItem::Rotate { entity, from, to } => {
+                    if let Ok(mut t) = transforms.get_mut(*entity) {
+                        t.rotation = Quat::from_rotation_z(from.to_radians());
+                    }
+                    let t = *from;
+                    *from = *to;
+                    *to = t;
+                },
+                UndoItem::NameChange { entity, from } => {
+                    if let Ok(mut sd) = shapes.get_mut(*entity) {
+                        std::mem::swap(&mut sd.name, from);
+                    }
+                    // No need to update the item, so no need to replace
+                },
+                UndoItem::DeleteShape {
+                    name, 
+                    shape, 
+                    edges, 
+                    transform, 
+                    color, 
+                    note 
+                } => {
+                    bevy::log::error!("NOT IMPLEMENTED : DeleteShape");
+                },
+            }
+        }
+        else {
+            bevy::log::info!("Nothing to pop/unpop!");
+        }
+    }
+}