Major overhaul of input and communication systems

* Add input manager

* WIP lifetime hell

* Hell yeah, dark lifetime magic

* Replace events with actions in tools

* Fix borrow in GlobalEventHandler

* Fix typo in response-handler

* Distribute dispatch structure

* Add translation from events to actions

* Port default key actions to input_mapper

* Split actions macro

* Add handling for Ambiguous Mouse events

* Fix warnings and clippy lints

* Add actions macro

* WIP rework

* Add AsMessage macro

* Add implementation for derived enums

* Add macro implementation for top level message

* Add #[child] attribute to indicate derivation

* Replace some mentions of Actions and Responses with Message

* It compiles !!!

* Add functionality to some message handlers

* Add document rendering

* ICE

* Rework the previous code while keeping basic functionality

* Reduce parent-top-level macro args to only two

* Add workaround for ICE

* Fix cyclic reference in document.rs

* Make derive_transitive_child a bit more powerful

This addresses the todo that was left,
enabling arbitrary expressions to be passed as the last
parameter of a #[parent] attribute

* Adapt frontend message format

* Make responses use VecDeque

Our responses are a queue so we should use a queue type for them

* Move traits to sensible location

* Are we rectangle yet?

* Simplify, improve & document `derive_discriminant`

* Change `child` to `sub_discriminant`

This only applies to `ToDiscriminant`.
Code using `#[impl_message]` continues to work.

* Add docs for `derive_transitive_child`

* Finish docs and improve macros

The improvements are that impl_message now uses trait
resolution to obtain the parent's discriminant
and that derive_as_message now allows for non-unit
variants (which we don't use but it's nice to have,
just in case)

* Remove logging call

* Move files around and cleanup structure

* Fix proc macro doc tests

* Improve actions_fn!() macro

* Add ellipse tool

* Pass populated actions list to the input mapper

* Add KeyState bitvector

* Merge mouse buttons into "keyboard"

* Add macro for initialization of key mapper table

* Add syntactic sugar for the macro

* Implement mapping function

* Translate the remaining tools

* Fix shape tool

* Add keybindings for line and pen tool

* Fix modifiers

* Cleanup

* Add doc comments for the actions macro

* Fix formatting

* Rename MouseMove to PointerMove

* Add keybinds for tools

* Apply review suggestions

* Rename KeyMappings -> KeyMappingEntries

* Apply review changes

Co-authored-by: T0mstone <realt0mstone@gmail.com>
Co-authored-by: Paul Kupper <kupper.pa@gmail.com>

core/editor/src/misc/derivable_custom_traits.rs

@@ -0,0 +1,18 @@
+//! Traits that can be derived using macros from `graphite-proc-macros`
+
+use std::collections::HashMap;
+
+pub trait Hint {
+	fn hints(&self) -> HashMap<String, String>;
+}
+
+pub trait ToDiscriminant {
+	type Discriminant;
+
+	fn to_discriminant(&self) -> Self::Discriminant;
+}
+
+pub trait TransitiveChild: Into<Self::Parent> + Into<Self::TopParent> {
+	type TopParent;
+	type Parent;
+}

core/editor/src/misc/error.rs

@@ -0,0 +1,33 @@
+use crate::Color;
+use document_core::DocumentError;
+use thiserror::Error;
+
+/// The error type used by the Graphite editor.
+#[derive(Clone, Debug, Error)]
+pub enum EditorError {
+	#[error("Failed to execute operation: {0}")]
+	InvalidOperation(String),
+	#[error("{0}")]
+	Misc(String),
+	#[error("Tried to construct an invalid color {0:?}")]
+	Color(String),
+	#[error("The requested tool does not exist")]
+	UnknownTool,
+	#[error("The operation caused a document error {0:?}")]
+	Document(String),
+}
+
+macro_rules! derive_from {
+	($type:ty, $kind:ident) => {
+		impl From<$type> for EditorError {
+			fn from(error: $type) -> Self {
+				EditorError::$kind(format!("{:?}", error))
+			}
+		}
+	};
+}
+
+derive_from!(&str, Misc);
+derive_from!(String, Misc);
+derive_from!(Color, Color);
+derive_from!(DocumentError, Document);

core/editor/src/misc/macros.rs

@@ -0,0 +1,138 @@
+/// Counts args in the macro invocation by adding `+ 1` for every arg.
+///
+/// # Example
+///
+/// ```ignore
+/// let x = count_args!(("example1"), (10), (25));
+/// assert_eq!(x, 3);
+/// ```
+/// expands to
+/// ```ignore
+/// let x = 0 + 1 + 1 + 1;
+/// assert_eq!(x, 3);
+/// ```
+macro_rules! count_args {
+	(@one $($t:tt)*) => { 1 };
+	($(($($x:tt)*)),*$(,)?) => {
+		0 $(+ count_args!(@one $($x)*))*
+	};
+}
+
+/// Generates a [`std::collections::HashMap`] for `ToolState`'s `tools` variable.
+///
+/// # Example
+///
+/// ```ignore
+/// let tools = gen_tools_hash_map! {
+/// 	Select => select::Select,
+/// 	Crop => crop::Crop,
+/// };
+/// ```
+/// expands to
+/// ```ignore
+/// let tools = {
+/// 	let mut hash_map: std::collections::HashMap<crate::tool::ToolType, Box<dyn crate::tool::Tool>> = std::collections::HashMap::with_capacity(count_args!(/* Macro args */));
+///
+/// 	hash_map.insert(crate::tool::ToolType::Select, Box::new(select::Select::default()));
+/// 	hash_map.insert(crate::tool::ToolType::Crop, Box::new(crop::Crop::default()));
+///
+/// 	hash_map
+/// };
+/// ```
+macro_rules! gen_tools_hash_map {
+	($($enum_variant:ident => $struct_path:ty),* $(,)?) => {{
+		let mut hash_map: ::std::collections::HashMap<$crate::tool::ToolType, ::std::boxed::Box<dyn for<'a> $crate::message_prelude::MessageHandler<$crate::tool::tool_messages::ToolMessage,$crate::tool::ToolActionHandlerData<'a>>>> = ::std::collections::HashMap::with_capacity(count_args!($(($enum_variant)),*));
+		$(hash_map.insert($crate::tool::ToolType::$enum_variant, ::std::boxed::Box::new(<$struct_path>::default()));)*
+
+		hash_map
+	}};
+}
+
+/// Creates a string representation of an enum value that exactly matches the given name of each enum variant
+///
+/// # Example
+///
+/// ```ignore
+/// enum E {
+/// 	A(u8),
+/// 	B
+/// }
+///
+/// // this line is important
+/// use E::*;
+///
+/// let a = E::A(7);
+/// let s = match_variant_name!(match (a) { A, B });
+/// ```
+///
+/// expands to
+///
+/// ```ignore
+/// // ...
+///
+/// let s = match a {
+/// 	A { .. } => "A",
+/// 	B { .. } => "B"
+/// };
+/// ```
+macro_rules! match_variant_name {
+    (match ($e:expr) { $($v:ident),* $(,)? }) => {
+		match $e {
+			$(
+				$v { .. } => stringify!($v)
+			),*
+		}
+	};
+}
+
+/// Syntax sugar for initializing an `ActionList`
+///
+/// # Example
+///
+/// ```ignore
+/// actions!(DocumentMessage::Undo, DocumentMessage::Redo);
+/// ```
+///
+/// expands to:
+/// ```ignore
+/// vec![vec![DocumentMessage::Undo, DocumentMessage::Redo]];
+/// ```
+///
+/// and
+/// ```ignore
+/// actions!(DocumentMessage; Undo, Redo);
+/// ```
+///
+/// expands to:
+/// ```ignore
+/// vec![vec![DocumentMessage::Undo, DocumentMessage::Redo]];
+/// ```
+///
+macro_rules! actions {
+	($($v:expr),* $(,)?) => {{
+		 vec![$(vec![$v.into()]),*]
+	}};
+	($name:ident; $($v:ident),* $(,)?) => {{
+		 vec![vec![$(($name::$v).into()),*]]
+	}};
+}
+
+/// Does the same thing as the `actions!` macro but wraps everything in:
+///
+/// ```ignore
+/// fn actions(&self) -> ActionList {
+///		actions!(…)
+/// }
+/// ```
+macro_rules! advertise_actions {
+	($($v:expr),* $(,)?) => {
+		fn actions(&self) -> $crate::communication::ActionList {
+			 actions!($($v),*)
+		}
+	};
+	($name:ident; $($v:ident),* $(,)?) => {
+		fn actions(&self) -> $crate::communication::ActionList {
+			 actions!($name; $($v),*)
+		}
+	}
+}

core/editor/src/misc/mod.rs

@@ -0,0 +1,7 @@
+#[macro_use]
+pub mod macros;
+pub mod derivable_custom_traits;
+mod error;
+
+pub use error::EditorError;
+pub use macros::*;