Restructure project directories (#333)

`/client/web` -> `/frontend`
`/client/cli` -> *delete for now*
`/client/native` -> *delete for now*
`/core/editor` -> `/editor`
`/core/document` -> `/graphene`
`/core/renderer` -> `/charcoal`
`/core/proc-macro` -> `/proc-macros` *(now plural)*

editor/src/tool/tool_message_handler.rs

@@ -0,0 +1,126 @@
+use crate::message_prelude::*;
+use graphene::color::Color;
+
+use crate::input::InputPreprocessor;
+use crate::{
+	document::DocumentMessageHandler,
+	tool::{tool_options::ToolOptions, DocumentToolData, ToolFsmState, ToolType},
+};
+use std::collections::VecDeque;
+
+#[impl_message(Message, Tool)]
+#[derive(PartialEq, Clone, Debug)]
+pub enum ToolMessage {
+	SelectTool(ToolType),
+	SelectPrimaryColor(Color),
+	SelectSecondaryColor(Color),
+	SwapColors,
+	ResetColors,
+	SetToolOptions(ToolType, ToolOptions),
+	#[child]
+	Fill(FillMessage),
+	#[child]
+	Rectangle(RectangleMessage),
+	#[child]
+	Ellipse(EllipseMessage),
+	#[child]
+	Select(SelectMessage),
+	#[child]
+	Line(LineMessage),
+	#[child]
+	Crop(CropMessage),
+	#[child]
+	Eyedropper(EyedropperMessage),
+	#[child]
+	Navigate(NavigateMessage),
+	#[child]
+	Path(PathMessage),
+	#[child]
+	Pen(PenMessage),
+	#[child]
+	Shape(ShapeMessage),
+}
+
+#[derive(Debug, Default)]
+pub struct ToolMessageHandler {
+	tool_state: ToolFsmState,
+}
+impl MessageHandler<ToolMessage, (&DocumentMessageHandler, &InputPreprocessor)> for ToolMessageHandler {
+	fn process_action(&mut self, message: ToolMessage, data: (&DocumentMessageHandler, &InputPreprocessor), responses: &mut VecDeque<Message>) {
+		let (document, input) = data;
+		use ToolMessage::*;
+		match message {
+			SelectPrimaryColor(c) => {
+				self.tool_state.document_tool_data.primary_color = c;
+				update_working_colors(&self.tool_state.document_tool_data, responses);
+			}
+			SelectSecondaryColor(c) => {
+				self.tool_state.document_tool_data.secondary_color = c;
+				update_working_colors(&self.tool_state.document_tool_data, responses);
+			}
+			SelectTool(tool) => {
+				let mut reset = |tool| match tool {
+					ToolType::Ellipse => responses.push_back(EllipseMessage::Abort.into()),
+					ToolType::Rectangle => responses.push_back(RectangleMessage::Abort.into()),
+					ToolType::Shape => responses.push_back(ShapeMessage::Abort.into()),
+					ToolType::Line => responses.push_back(LineMessage::Abort.into()),
+					ToolType::Pen => responses.push_back(PenMessage::Abort.into()),
+					_ => (),
+				};
+				reset(tool);
+				reset(self.tool_state.tool_data.active_tool_type);
+				self.tool_state.tool_data.active_tool_type = tool;
+
+				responses.push_back(FrontendMessage::SetActiveTool { tool_name: tool.to_string() }.into())
+			}
+			SwapColors => {
+				let doc_data = &mut self.tool_state.document_tool_data;
+				std::mem::swap(&mut doc_data.primary_color, &mut doc_data.secondary_color);
+				update_working_colors(doc_data, responses);
+			}
+			ResetColors => {
+				let doc_data = &mut self.tool_state.document_tool_data;
+				doc_data.primary_color = Color::BLACK;
+				doc_data.secondary_color = Color::WHITE;
+				update_working_colors(doc_data, responses);
+			}
+			SetToolOptions(tool_type, tool_options) => {
+				self.tool_state.document_tool_data.tool_options.insert(tool_type, tool_options);
+			}
+			message => {
+				let tool_type = match message {
+					Fill(_) => ToolType::Fill,
+					Rectangle(_) => ToolType::Rectangle,
+					Ellipse(_) => ToolType::Ellipse,
+					Shape(_) => ToolType::Shape,
+					Line(_) => ToolType::Line,
+					Pen(_) => ToolType::Pen,
+					Select(_) => ToolType::Select,
+					Crop(_) => ToolType::Crop,
+					Eyedropper(_) => ToolType::Eyedropper,
+					Navigate(_) => ToolType::Navigate,
+					Path(_) => ToolType::Path,
+					_ => unreachable!(),
+				};
+				if let Some(tool) = self.tool_state.tool_data.tools.get_mut(&tool_type) {
+					tool.process_action(message, (document, &self.tool_state.document_tool_data, input), responses);
+				}
+			}
+		}
+	}
+	fn actions(&self) -> ActionList {
+		let mut list = actions!(ToolMessageDiscriminant; ResetColors, SwapColors, SelectTool, SetToolOptions);
+		list.extend(self.tool_state.tool_data.active_tool().actions());
+		list
+	}
+}
+
+fn update_working_colors(doc_data: &DocumentToolData, responses: &mut VecDeque<Message>) {
+	responses.push_back(
+		FrontendMessage::UpdateWorkingColors {
+			primary: doc_data.primary_color,
+			secondary: doc_data.secondary_color,
+		}
+		.into(),
+	);
+}