use std::sync::Arc;

use crate::messages::frontend::utility_types::FileType;
use crate::messages::prelude::*;
use dyn_any::DynAny;
use graph_craft::document::value::{EditorMetadata, RenderOutput, TaggedValue};
use graph_craft::document::{CompilationMetadata, DocumentNode, NodeNetwork, generate_uuid};
use graph_craft::proto::GraphErrors;
use graphene_std::EditorContext;
use graphene_std::memo::MonitorIntrospectResult;
use graphene_std::renderer::format_transform_matrix;
use graphene_std::text::FontCache;
use graphene_std::uuid::SNI;

mod runtime_io;
pub use runtime_io::NodeRuntimeIO;

mod runtime;
pub use runtime::*;

#[derive(Clone, Debug, Default, PartialEq, Hash, serde::Serialize, serde::Deserialize)]
pub struct CompilationRequest {
	pub network: NodeNetwork,
	// Data which is available from scope inputs
	pub font_cache: Arc<FontCache>,
	pub editor_metadata: EditorMetadata,
}

pub struct CompilationResponse {
	result: Result<CompilationMetadata, String>,
	node_graph_errors: GraphErrors,
}

#[derive(Debug, Default, serde::Serialize, serde::Deserialize)]
pub struct CacheEnableRequest {
	nodes_to_enable: HashSet<SNI>,
}

// Metadata the editor sends when evaluating the network
#[derive(Debug, Default, DynAny, serde::Serialize, serde::Deserialize)]
pub struct EvaluationRequest {
	pub evaluation_id: u64,
	#[serde(skip)]
	pub context: EditorContext,
	pub node_to_evaluate: Option<SNI>,
	pub nodes_to_introspect: HashSet<SNI>,
}

// #[cfg_attr(feature = "decouple-execution", derive(serde::Serialize, serde::Deserialize))]
pub struct EvaluationResponse {
	evaluation_id: u64,
	result: Result<TaggedValue, String>,
	introspected_nodes: IntrospectionResponse,
}

#[derive(Debug, Clone, Default)]
pub struct IntrospectionResponse(pub Vec<(SNI, MonitorIntrospectResult)>);

impl PartialEq for IntrospectionResponse {
	fn eq(&self, _other: &Self) -> bool {
		false
	}
}

// #[cfg_attr(feature = "decouple-execution", derive(serde::Serialize, serde::Deserialize))]
pub enum NodeGraphUpdate {
	CompilationResponse(CompilationResponse),
	EvaluationResponse(EvaluationResponse),
}

#[derive(Debug, Default)]
pub struct NodeGraphExecutor {
	runtime_io: NodeRuntimeIO,
	futures: HashMap<u64, EvaluationContext>,
}

#[derive(Debug, Clone)]
struct EvaluationContext {
	export_config: Option<ExportConfig>,
}

impl NodeGraphExecutor {
	/// A local runtime is useful on threads since having global state causes flakes
	// #[cfg(test)]
	// pub(crate) fn new_with_local_runtime() -> (NodeRuntime, Self) {
	// 	let (request_sender, request_receiver) = std::sync::mpsc::channel();
	// 	let (response_sender, response_receiver) = std::sync::mpsc::channel();
	// 	let node_runtime = NodeRuntime::new(request_receiver, response_sender);

	// 	let node_executor = Self {
	// 		futures: HashMap::new(),
	// 		runtime_io: NodeRuntimeIO::with_channels(request_sender, response_receiver),
	// 	};
	// 	(node_runtime, node_executor)
	// }

	/// Updates the network to monitor all inputs. Useful for the testing.
	// #[cfg(test)]
	// pub(crate) fn update_node_graph_instrumented(&mut self, document: &mut DocumentMessageHandler) -> Result<Instrumented, String> {
	// 	let mut network = document.network_interface.document_network().clone();
	// 	let instrumented = Instrumented::new(&mut network);

	// 	self.runtime_io
	// 		.send(GraphRuntimeRequest::CompilationRequest(CompilationRequest { network, ..Default::default() }))
	// 		.map_err(|e| e.to_string())?;
	// 	Ok(instrumented)
	// }

	/// Compile the network
	pub fn submit_node_graph_compilation(&mut self, compilation_request: CompilationRequest) {
		if let Err(error) = self.runtime_io.try_send(GraphRuntimeRequest::CompilationRequest(compilation_request)) {
			log::error!("Could not send evaluation request. {:?}", error);
			return;
		}
	}

	// // Adds a request to set disabled cache nodes (automatically placed on the output of each node) to save the value of their first exeuction
	// pub fn submit_node_graph_cache_enable(&mut self, nodes_to_enable: HashSet<SNI>) {
	// 	if let Err(error) = self.runtime_io.try_send(GraphRuntimeRequest::CacheEnableRequest(CacheEnableRequest { nodes_to_enable })) {
	// 		log::error!("Could not send evaluation request. {:?}", error);
	// 		return;
	// 	}
	// }

	/// Adds an evaluation request for whatever current network is cached.
	pub fn submit_node_graph_evaluation(&mut self, context: EditorContext, node_to_evaluate: Option<SNI>, export_config: Option<ExportConfig>, nodes_to_introspect: HashSet<SNI>) {
		let evaluation_id = generate_uuid();
		if let Err(error) = self.runtime_io.try_send(GraphRuntimeRequest::EvaluationRequest(EvaluationRequest {
			evaluation_id,
			context,
			node_to_evaluate,
			nodes_to_introspect,
		})) {
			log::error!("Could not send evaluation request. {:?}", error);
			return;
		}
		let evaluation_context = EvaluationContext { export_config };
		self.futures.insert(evaluation_id, evaluation_context);
	}

	// pub fn submit_node_graph_introspection(&mut self, nodes_to_introspect: HashSet<SNI>) {
	// 	if let Err(error) = self.runtime_io.try_send(GraphRuntimeRequest::IntrospectionRequest(nodes_to_introspect)) {
	// 		log::error!("Could not send evaluation request. {:?}", error);
	// 		return;
	// 	}
	// }

	// Continuously poll the executor (called by request animation frame)
	pub fn poll_node_graph_evaluation(&mut self, document: &mut DocumentMessageHandler, responses: &mut VecDeque<Message>) -> Result<(), String> {
		if let Ok(response) = self.runtime_io.receive() {
			self.runtime_io.busy = false;
			match response {
				NodeGraphUpdate::CompilationResponse(compilation_response) => {
					let CompilationResponse { node_graph_errors, result } = compilation_response;
					let compilation_metadata = match result {
						Err(e) => {
							// Clear the click targets while the graph is in an un-renderable state
							document.network_interface.update_click_targets(HashMap::new());
							document.network_interface.update_vector_modify(HashMap::new());

							document.node_graph_handler.node_graph_errors = node_graph_errors;
							responses.add(NodeGraphMessage::SendGraph);

							log::trace!("{e}");
							return Err(format!("Node graph evaluation failed:\n{e}"));
						}
						Ok(result) => result,
					};
					// Always evaluate after a compilation
					responses.add_front(PortfolioMessage::EvaluateActiveDocumentWithThumbnails);
					responses.add_front(PortfolioMessage::ProcessCompilationResponse { compilation_metadata });
				}
				NodeGraphUpdate::EvaluationResponse(EvaluationResponse {
					evaluation_id,
					result,
					introspected_nodes,
				}) => {
					responses.add(OverlaysMessage::Draw);

					let node_graph_output = match result {
						Ok(output) => output,
						Err(e) => {
							// Clear the click targets while the graph is in an un-renderable state
							document.network_interface.update_click_targets(HashMap::new());
							document.network_interface.update_vector_modify(HashMap::new());
							return Err(format!("Node graph evaluation failed:\n{e}"));
						}
					};
					let render_output = match node_graph_output {
						TaggedValue::RenderOutput(render_output) => render_output,
						value => {
							return Err(format!("Incorrect render type for exporting {:?} (expected NetworkOutput)", value.ty()));
						}
					};

					let evaluation_context = self.futures.remove(&evaluation_id).ok_or_else(|| "Invalid generation ID".to_string())?;
					if let Some(export_config) = evaluation_context.export_config {
						// Export
						let graphene_std::wasm_application_io::RenderOutputType::Svg(svg) = render_output.data else {
							return Err("Incorrect render type for exporting (expected RenderOutput::Svg)".to_string());
						};

						match export_config.file_type {
							FileType::Svg => {
								responses.add(FrontendMessage::TriggerDownloadTextFile {
									document: svg,
									name: export_config.file_name,
								});
							}
							_ => {
								responses.add(FrontendMessage::TriggerDownloadImage {
									svg,
									name: export_config.file_name,
									mime: export_config.file_type.to_mime().to_string(),
									size: export_config.size.into(),
								});
							}
						}
					} else {
						// Update artwork
						self.process_node_graph_output(render_output, introspected_nodes, responses)?
					}
				} // NodeGraphUpdate::IntrospectionResponse(introspection_response) => {
				  // 	responses.add_front(Message::ProcessIntrospectionQueue(introspection_response));
				  // }
			}
		}
		Ok(())
	}

	fn process_node_graph_output(&self, render_output: RenderOutput, introspected_nodes: IntrospectionResponse, responses: &mut VecDeque<Message>) -> Result<(), String> {
		match render_output.data {
			graphene_std::wasm_application_io::RenderOutputType::Svg(svg) => {
				// Send to frontend
				responses.add(FrontendMessage::UpdateDocumentArtwork { svg });
			}
			graphene_std::wasm_application_io::RenderOutputType::CanvasFrame(frame) => {
				let matrix = format_transform_matrix(frame.transform);
				let transform = if matrix.is_empty() { String::new() } else { format!(" transform=\"{}\"", matrix) };
				let svg = format!(
					r#"<svg><foreignObject width="{}" height="{}"{transform}><div data-canvas-placeholder="canvas{}"></div></foreignObject></svg>"#,
					frame.resolution.x, frame.resolution.y, frame.surface_id.0
				);
				responses.add(FrontendMessage::UpdateDocumentArtwork { svg });
			}
			_ => {
				return Err(format!("Invalid node graph output type: {:#?}", render_output.data));
			}
		}
		let context_during_evaluation = self
			.runtime_io
			.context_receiver
			.try_iter()
			.map(|(ids, index, context)| (ids, index, format!("{:?}", context)))
			.collect::<Vec<_>>();
		if context_during_evaluation.len() != 0 {
			responses.add_front(FrontendMessage::UpdateContextDuringEvaluation { context_during_evaluation });
		}
		responses.add_front(Message::ProcessEvaluationQueue(render_output.metadata, introspected_nodes));
		Ok(())
	}
}

// Re-export for usage by tests in other modules
// #[cfg(test)]
// pub use test::Instrumented;

// #[cfg(test)]
// mod test {
// 	use std::sync::Arc;

// 	use super::*;
// 	use crate::messages::portfolio::document::utility_types::network_interface::NodeNetworkInterface;
// 	use crate::test_utils::test_prelude::{self, NodeGraphLayer};
// 	use graph_craft::ProtoNodeIdentifier;
// 	use graph_craft::document::NodeNetwork;
// 	use graphene_std::Context;
// 	use graphene_std::NodeInputDecleration;
// 	use graphene_std::memo::IORecord;
// 	use test_prelude::LayerNodeIdentifier;

// 	/// Stores all of the monitor nodes that have been attached to a graph
// 	#[derive(Default)]
// 	pub struct Instrumented {
// 		protonodes_by_name: HashMap<ProtoNodeIdentifier, Vec<Vec<Vec<NodeId>>>>,
// 		protonodes_by_path: HashMap<Vec<NodeId>, Vec<Vec<NodeId>>>,
// 	}

// 	impl Instrumented {
// 		/// Adds montior nodes to the network
// 		fn add(&mut self, network: &mut NodeNetwork, path: &mut Vec<NodeId>) {
// 			// Required to do seperately to satiate the borrow checker.
// 			let mut monitor_nodes = Vec::new();
// 			for (id, node) in network.nodes.iter_mut() {
// 				// Recursively instrument
// 				if let DocumentNodeImplementation::Network(nested) = &mut node.implementation {
// 					path.push(*id);
// 					self.add(nested, path);
// 					path.pop();
// 				}
// 				let mut monitor_node_ids = Vec::with_capacity(node.inputs.len());
// 				for input in &mut node.inputs {
// 					let node_id = NodeId::new();
// 					let old_input = std::mem::replace(input, NodeInput::node(node_id, 0));
// 					monitor_nodes.push((old_input, node_id));
// 					path.push(node_id);
// 					monitor_node_ids.push(path.clone());
// 					path.pop();
// 				}
// 				if let DocumentNodeImplementation::ProtoNode(identifier) = &mut node.implementation {
// 					path.push(*id);
// 					self.protonodes_by_name.entry(identifier.clone()).or_default().push(monitor_node_ids.clone());
// 					self.protonodes_by_path.insert(path.clone(), monitor_node_ids);
// 					path.pop();
// 				}
// 			}
// 			for (input, monitor_id) in monitor_nodes {
// 				let monitor_node = DocumentNode {
// 					inputs: vec![input],
// 					implementation: DocumentNodeImplementation::ProtoNode(graphene_std::memo::monitor::IDENTIFIER),
// 					manual_composition: Some(graph_craft::generic!(T)),
// 					skip_deduplication: true,
// 					..Default::default()
// 				};
// 				network.nodes.insert(monitor_id, monitor_node);
// 			}
// 		}

// 		/// Instrument a graph and return a new [Instrumented] state.
// 		pub fn new(network: &mut NodeNetwork) -> Self {
// 			let mut instrumented = Self::default();
// 			instrumented.add(network, &mut Vec::new());
// 			instrumented
// 		}

// 		fn downcast<Input: NodeInputDecleration>(dynamic: Arc<dyn std::any::Any + Send + Sync>) -> Option<Input::Result>
// 		where
// 			Input::Result: Send + Sync + Clone + 'static,
// 		{
// 			// This is quite inflexible since it only allows the footprint as inputs.
// 			if let Some(x) = dynamic.downcast_ref::<IORecord<(), Input::Result>>() {
// 				Some(x.output.clone())
// 			} else if let Some(x) = dynamic.downcast_ref::<IORecord<Footprint, Input::Result>>() {
// 				Some(x.output.clone())
// 			} else if let Some(x) = dynamic.downcast_ref::<IORecord<Context, Input::Result>>() {
// 				Some(x.output.clone())
// 			} else {
// 				panic!("cannot downcast type for introspection");
// 			}
// 		}

// 		/// Grab all of the values of the input every time it occurs in the graph.
// 		pub fn grab_all_input<'a, Input: NodeInputDecleration + 'a>(&'a self, runtime: &'a NodeRuntime) -> impl Iterator<Item = Input::Result> + 'a
// 		where
// 			Input::Result: Send + Sync + Clone + 'static,
// 		{
// 			self.protonodes_by_name
// 				.get(&Input::identifier())
// 				.map_or([].as_slice(), |x| x.as_slice())
// 				.iter()
// 				.filter_map(|inputs| inputs.get(Input::INDEX))
// 				.filter_map(|input_monitor_node| runtime.executor.introspect(input_monitor_node).ok())
// 				.filter_map(Instrumented::downcast::<Input>)
// 		}

// 		pub fn grab_protonode_input<Input: NodeInputDecleration>(&self, path: &Vec<NodeId>, runtime: &NodeRuntime) -> Option<Input::Result>
// 		where
// 			Input::Result: Send + Sync + Clone + 'static,
// 		{
// 			let input_monitor_node = self.protonodes_by_path.get(path)?.get(Input::INDEX)?;

// 			let dynamic = runtime.executor.introspect(input_monitor_node).ok()?;

// 			Self::downcast::<Input>(dynamic)
// 		}

// 		pub fn grab_input_from_layer<Input: NodeInputDecleration>(&self, layer: LayerNodeIdentifier, network_interface: &NodeNetworkInterface, runtime: &NodeRuntime) -> Option<Input::Result>
// 		where
// 			Input::Result: Send + Sync + Clone + 'static,
// 		{
// 			let node_graph_layer = NodeGraphLayer::new(layer, network_interface);
// 			let node = node_graph_layer.upstream_node_id_from_protonode(Input::identifier())?;
// 			self.grab_protonode_input::<Input>(&vec![node], runtime)
// 		}
// 	}
// }