Graphite/node-graph/gcore/src/application_io.rs

use crate::raster::ImageFrame;
use crate::text::FontCache;
use crate::transform::{Transform, TransformMut};
use crate::{Color, Node};

use dyn_any::{StaticType, StaticTypeSized};

use alloc::sync::Arc;
use core::fmt::Debug;
use core::future::Future;
use core::hash::{Hash, Hasher};
use core::pin::Pin;
use glam::DAffine2;

#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
pub struct SurfaceId(pub u64);

#[derive(Debug, Clone, Copy, PartialEq)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
pub struct SurfaceFrame {
	pub surface_id: SurfaceId,
	pub transform: DAffine2,
}

impl Hash for SurfaceFrame {
	fn hash<H: Hasher>(&self, state: &mut H) {
		self.surface_id.hash(state);
		self.transform.to_cols_array().iter().for_each(|x| x.to_bits().hash(state));
	}
}

unsafe impl StaticType for SurfaceFrame {
	type Static = SurfaceFrame;
}

impl<S> From<SurfaceHandleFrame<S>> for SurfaceFrame {
	fn from(x: SurfaceHandleFrame<S>) -> Self {
		Self {
			surface_id: x.surface_handle.surface_id,
			transform: x.transform,
		}
	}
}

#[derive(Clone, Debug)]
pub struct SurfaceHandle<Surface> {
	pub surface_id: SurfaceId,
	pub surface: Surface,
}

unsafe impl<T: 'static> StaticType for SurfaceHandle<T> {
	type Static = SurfaceHandle<T>;
}

#[derive(Clone, Debug)]
pub struct SurfaceHandleFrame<Surface> {
	pub surface_handle: Arc<SurfaceHandle<Surface>>,
	pub transform: DAffine2,
}

unsafe impl<T: 'static> StaticType for SurfaceHandleFrame<T> {
	type Static = SurfaceHandleFrame<T>;
}

impl<T> Transform for SurfaceHandleFrame<T> {
	fn transform(&self) -> DAffine2 {
		self.transform
	}
}

impl<T> TransformMut for SurfaceHandleFrame<T> {
	fn transform_mut(&mut self) -> &mut DAffine2 {
		&mut self.transform
	}
}

// TODO: think about how to automatically clean up memory
/*
impl<'a, Surface> Drop for SurfaceHandle<'a, Surface> {
	fn drop(&mut self) {
		self.application_io.destroy_surface(self.surface_id)
	}
}*/

pub type ResourceFuture = Pin<Box<dyn Future<Output = Result<Arc<[u8]>, ApplicationError>>>>;

pub trait ApplicationIo {
	type Surface;
	type Executor;
	fn create_surface(&self) -> SurfaceHandle<Self::Surface>;
	fn destroy_surface(&self, surface_id: SurfaceId);
	fn gpu_executor(&self) -> Option<&Self::Executor> {
		None
	}
	fn load_resource(&self, url: impl AsRef<str>) -> Result<ResourceFuture, ApplicationError>;
}

impl<T: ApplicationIo> ApplicationIo for &T {
	type Surface = T::Surface;
	type Executor = T::Executor;

	fn create_surface(&self) -> SurfaceHandle<T::Surface> {
		(**self).create_surface()
	}

	fn destroy_surface(&self, surface_id: SurfaceId) {
		(**self).destroy_surface(surface_id)
	}

	fn gpu_executor(&self) -> Option<&T::Executor> {
		(**self).gpu_executor()
	}

	fn load_resource<'a>(&self, url: impl AsRef<str>) -> Result<ResourceFuture, ApplicationError> {
		(**self).load_resource(url)
	}
}

#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub enum ApplicationError {
	NotFound,
	InvalidUrl,
}

#[derive(Debug, Clone)]
pub enum NodeGraphUpdateMessage {
	ImaginateStatusUpdate,
}

pub trait NodeGraphUpdateSender {
	fn send(&self, message: NodeGraphUpdateMessage);
}

pub trait GetImaginatePreferences {
	fn get_host_name(&self) -> &str;
}

pub struct EditorApi<'a, Io> {
	pub image_frame: Option<ImageFrame<Color>>,
	pub font_cache: &'a FontCache,
	pub application_io: &'a Io,
	pub node_graph_message_sender: &'a dyn NodeGraphUpdateSender,
	pub imaginate_preferences: &'a dyn GetImaginatePreferences,
}

impl<'a, Io> Clone for EditorApi<'a, Io> {
	fn clone(&self) -> Self {
		Self {
			image_frame: self.image_frame.clone(),
			font_cache: self.font_cache,
			application_io: self.application_io,
			node_graph_message_sender: self.node_graph_message_sender,
			imaginate_preferences: self.imaginate_preferences,
		}
	}
}

impl<'a, T> PartialEq for EditorApi<'a, T> {
	fn eq(&self, other: &Self) -> bool {
		self.image_frame == other.image_frame && self.font_cache == other.font_cache
	}
}

impl<'a, T> Hash for EditorApi<'a, T> {
	fn hash<H: Hasher>(&self, state: &mut H) {
		self.image_frame.hash(state);
		self.font_cache.hash(state);
	}
}

impl<'a, T> Debug for EditorApi<'a, T> {
	fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
		f.debug_struct("EditorApi").field("image_frame", &self.image_frame).field("font_cache", &self.font_cache).finish()
	}
}

unsafe impl<T: StaticTypeSized> StaticType for EditorApi<'_, T> {
	type Static = EditorApi<'static, T::Static>;
}

impl<'a, T> AsRef<EditorApi<'a, T>> for EditorApi<'a, T> {
	fn as_ref(&self) -> &EditorApi<'a, T> {
		self
	}
}

#[derive(Debug, Clone, Copy, Default)]
pub struct ExtractImageFrame;

impl<'a: 'input, 'input, T> Node<'input, EditorApi<'a, T>> for ExtractImageFrame {
	type Output = ImageFrame<Color>;
	fn eval(&'input self, editor_api: EditorApi<'a, T>) -> Self::Output {
		editor_api.image_frame.unwrap_or(ImageFrame::identity())
	}
}

impl ExtractImageFrame {
	pub fn new() -> Self {
		Self
	}
}