Implement Line tool (#71)

* Add Line tool

core/editor/src/dispatcher/events.rs

@@ -111,6 +111,7 @@ pub enum Key {
 	KeyR,
 	KeyM,
 	KeyE,
+	KeyL,
 	KeyV,
 	KeyX,
 	KeyZ,

core/editor/src/dispatcher/mod.rs

@@ -63,6 +63,12 @@ impl Dispatcher {
 							tool_name: ToolType::Select.to_string(),
 						});
 					}
+					Key::KeyL => {
+						editor_state.tool_state.active_tool_type = ToolType::Line;
+						self.dispatch_response(Response::SetActiveTool {
+							tool_name: ToolType::Line.to_string(),
+						});
+					}
 					Key::KeyM => {
 						editor_state.tool_state.active_tool_type = ToolType::Rectangle;
 						self.dispatch_response(Response::SetActiveTool {

core/editor/src/tools/line.rs

@@ -1,13 +1,75 @@
 use crate::events::{Event, Response};
-use crate::tools::Tool;
+use crate::events::{Key, MouseKeys, ViewportPosition};
+use crate::tools::{Fsm, Tool};
 use crate::Document;
 use document_core::Operation;
 
 #[derive(Default)]
-pub struct Line;
+pub struct Line {
+	fsm_state: LineToolFsmState,
+	data: LineToolData,
+}
 
 impl Tool for Line {
 	fn handle_input(&mut self, event: &Event, document: &Document) -> (Vec<Response>, Vec<Operation>) {
-		todo!();
+		let mut responses = Vec::new();
+		let mut operations = Vec::new();
+		self.fsm_state = self.fsm_state.transition(event, document, &mut self.data, &mut responses, &mut operations);
+
+		(responses, operations)
+	}
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum LineToolFsmState {
+	Ready,
+	LmbDown,
+}
+
+impl Default for LineToolFsmState {
+	fn default() -> Self {
+		LineToolFsmState::Ready
+	}
+}
+#[derive(Clone, Debug, Default)]
+struct LineToolData {
+	drag_start: ViewportPosition,
+}
+
+impl Fsm for LineToolFsmState {
+	type ToolData = LineToolData;
+
+	fn transition(self, event: &Event, document: &Document, data: &mut Self::ToolData, responses: &mut Vec<Response>, operations: &mut Vec<Operation>) -> Self {
+		match (self, event) {
+			(LineToolFsmState::Ready, Event::MouseDown(mouse_state)) if mouse_state.mouse_keys.contains(MouseKeys::LEFT) => {
+				data.drag_start = mouse_state.position;
+				LineToolFsmState::LmbDown
+			}
+			(LineToolFsmState::Ready, Event::KeyDown(Key::KeyZ)) => {
+				if let Some(id) = document.root.list_layers().last() {
+					operations.push(Operation::DeleteLayer { path: vec![*id] })
+				}
+				LineToolFsmState::Ready
+			}
+			// TODO - Check for left mouse button
+			(LineToolFsmState::LmbDown, Event::MouseUp(mouse_state)) => {
+				let distance = data.drag_start.distance(&mouse_state.position);
+				log::info!("draw Line with distance: {:.2}", distance);
+				let start = data.drag_start;
+				let end = mouse_state.position;
+				operations.push(Operation::AddLine {
+					path: vec![],
+					insert_index: -1,
+					x0: start.x as f64,
+					y0: start.y as f64,
+					x1: end.x as f64,
+					y1: end.y as f64,
+				});
+
+				LineToolFsmState::Ready
+			}
+
+			_ => self,
+		}
 	}
 }