Add drag-and-drop support to the file picker dropdown widget (#4551)

Add drag-and-drop file ingest into file picker dropdowns

editor/src/messages/layout/utility_types/widgets/input_widgets.rs

@@ -3,6 +3,7 @@ use crate::messages::input_mapper::utility_types::misc::ActionShortcut;
 use crate::messages::layout::utility_types::widget_prelude::*;
 use crate::messages::message::Message;
 use crate::messages::portfolio::document::node_graph::document_node_definitions::DefinitionIdentifier;
+use crate::messages::portfolio::ingest::utility_types::IngestAction;
 use derivative::*;
 use graphene_std::Color;
 use graphene_std::color::SRGBA8;
@@ -83,6 +84,9 @@ pub struct DropdownInput {
 	pub virtual_scrolling: bool,
 	#[derivative(Default(value = "true"))]
 	pub interactive: bool,
+	// Where a file dropped on the widget is sent, which also makes the widget take dropped files
+	#[serde(rename = "fileDropAction")]
+	pub file_drop_action: Option<IngestAction>,
 
 	// Sizing
 	#[serde(rename = "minWidth")]

editor/src/messages/portfolio/document/node_graph/node_properties.rs

@@ -7,7 +7,7 @@ use crate::messages::portfolio::document::node_graph::document_node_definitions:
 use crate::messages::portfolio::document::utility_types::document_metadata::LayerNodeIdentifier;
 use crate::messages::portfolio::document::utility_types::network_interface::{InputConnector, NodeNetworkInterface};
 use crate::messages::portfolio::fonts::utility_types::FontCatalogStyle;
-use crate::messages::portfolio::ingest::utility_types::TypeFilter;
+use crate::messages::portfolio::ingest::utility_types::{IngestAction, TypeFilter};
 use crate::messages::prelude::*;
 use crate::messages::tool::common_functionality::graph_modification_utils;
 use choice::enum_choice;
@@ -1290,7 +1290,7 @@ pub fn font_widget(parameter_widgets_info: ParameterWidgetsInfo) -> LayoutGroup
 	font_widgets.into_iter().chain(style_widgets.unwrap_or_default()).collect::<Vec<_>>().into()
 }
 
-/// A dropdown of the document's uploaded files, led by "None" and a "Browse…" entry that uploads another file matching the given filters.
+/// A dropdown of the document's uploaded files, led by "None" and a "Browse…" entry that uploads another file matching the given filters, as dropping a file onto it also does.
 pub fn resource_widget(parameter_widgets_info: ParameterWidgetsInfo, filters: Vec<TypeFilter>) -> Vec<WidgetInstance> {
 	let mut widgets = start_widgets(&parameter_widgets_info);
 
@@ -1351,6 +1351,8 @@ pub fn resource_widget(parameter_widgets_info: ParameterWidgetsInfo, filters: Ve
 			]),
 		}
 	};
+	let file_drop_action = IngestAction::resource_input(document_id, node_id, index, &filters);
+
 	let none = MenuListEntry::new("none")
 		.label("None")
 		.tooltip_description("No resource assigned to this input.")
@@ -1386,7 +1388,10 @@ pub fn resource_widget(parameter_widgets_info: ParameterWidgetsInfo, filters: Ve
 
 	widgets.extend_from_slice(&[
 		Separator::new(SeparatorStyle::Unrelated).widget_instance(),
-		DropdownInput::new(vec![vec![none, browse], file_entries]).selected_index(selected_index).widget_instance(),
+		DropdownInput::new(vec![vec![none, browse], file_entries])
+			.selected_index(selected_index)
+			.file_drop_action(Some(file_drop_action))
+			.widget_instance(),
 	]);
 	widgets
 }

editor/src/messages/portfolio/ingest/ingest_message_handler.rs

@@ -33,18 +33,9 @@ impl MessageHandler<IngestMessage, IngestMessageContext> for IngestMessageHandle
 				input_index,
 				filters,
 			} => {
-				let accepted_types = filters.iter().flat_map(|filter| filter.types.iter().copied()).collect();
+				let action = IngestAction::resource_input(document_id, node_id, input_index, &filters);
 
-				responses.add(IngestMessage::Browse {
-					filters,
-					multiple: false,
-					action: IngestAction::ResourceInput {
-						document_id,
-						node_id,
-						input_index: input_index as u32,
-						accepted_types,
-					},
-				});
+				responses.add(IngestMessage::Browse { filters, multiple: false, action });
 			}
 			IngestMessage::Browse { filters, multiple, action } => responses.add(FrontendMessage::TriggerBrowse {
 				options: FileDialogOptions {
@@ -282,6 +273,24 @@ mod tests {
 		}
 	}
 
+	#[test]
+	fn browsing_for_a_resource_input_carries_the_action_a_dropped_file_uses() {
+		let filters = vec![TypeFilter::documents(), TypeFilter::raster()];
+		let accepted_types = [TypeFilter::documents().types, TypeFilter::raster().types].concat();
+		let dropped = IngestAction::resource_input(REQUESTING_DOCUMENT, NodeId(7), 1, &filters);
+		assert_eq!(dropped, resource_input(accepted_types));
+
+		let mut responses = VecDeque::new();
+		let message = IngestMessage::SetResourceInput {
+			document_id: REQUESTING_DOCUMENT,
+			node_id: NodeId(7),
+			input_index: 1,
+			filters,
+		};
+		IngestMessageHandler::default().process_message(message, &mut responses, IngestMessageContext { document_open: true });
+		assert!(matches!(&responses[0], Message::Portfolio(PortfolioMessage::Ingest(IngestMessage::Browse { action, .. })) if *action == dropped));
+	}
+
 	#[test]
 	fn truncated_image_only_shows_a_dialog() {
 		let png = Image::new(8, 8, Color::WHITE).to_png();

editor/src/messages/portfolio/ingest/utility_types.rs

@@ -39,6 +39,18 @@ pub enum IngestAction {
 	},
 }
 
+impl IngestAction {
+	/// Sends a file to a node's resource input, which takes only the types that its filters list.
+	pub fn resource_input(document_id: DocumentId, node_id: NodeId, input_index: usize, filters: &[TypeFilter]) -> Self {
+		Self::ResourceInput {
+			document_id,
+			node_id,
+			input_index: input_index as u32,
+			accepted_types: filters.iter().flat_map(|filter| filter.types.iter().copied()).collect(),
+		}
+	}
+}
+
 #[derive(Clone, Copy, Debug, Default, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 pub enum DataType {
 	GraphiteLegacy,

frontend/src/components/widgets/WidgetSpan.svelte

@@ -165,6 +165,9 @@
 					hoverInEntry: (e: CustomEvent) => widgetValueUpdate(index, e.detail, false),
 					hoverOutEntry: (e: CustomEvent) => widgetValueUpdate(index, e.detail, false),
 					selectedIndex: (e: CustomEvent) => widgetValueCommitAndUpdate(index, e.detail, true),
+					fileDrop: async (e: CustomEvent<File>) => {
+						if (props.fileDropAction) editor.ingestPicked(e.detail.name, e.detail.type, await e.detail.bytes(), props.fileDropAction);
+					},
 				},
 			}),
 		},

frontend/src/components/widgets/inputs/DropdownInput.svelte

@@ -4,7 +4,7 @@
 	import LayoutRow from "/src/components/layout/LayoutRow.svelte";
 	import IconLabel from "/src/components/widgets/labels/IconLabel.svelte";
 	import TextLabel from "/src/components/widgets/labels/TextLabel.svelte";
-	import type { MenuListEntry, ActionShortcut } from "/wrapper/pkg/graphite_wasm_wrapper";
+	import type { MenuListEntry, ActionShortcut, IngestAction } from "/wrapper/pkg/graphite_wasm_wrapper";
 
 	const DASH_ENTRY: MenuListEntry = {
 		value: "",
@@ -19,7 +19,7 @@
 		tooltipShortcut: undefined,
 	};
 
-	const dispatch = createEventDispatcher<{ selectedIndex: number; hoverInEntry: number; hoverOutEntry: number }>();
+	const dispatch = createEventDispatcher<{ selectedIndex: number; hoverInEntry: number; hoverOutEntry: number; fileDrop: File }>();
 
 	let self: LayoutRow | undefined;
 
@@ -35,6 +35,7 @@
 	// Behavior
 	export let virtualScrolling = false;
 	export let interactive = true;
+	export let fileDropAction: IngestAction | undefined = undefined;
 	// Sizing
 	export let minWidth = 0;
 	export let maxWidth = 0;
@@ -47,6 +48,7 @@
 	let activeEntrySkipWatcher = false;
 	let initialSelectedIndex: number | undefined = undefined;
 	let open = false;
+	let fileDragOver = false;
 
 	$: watchSelectedIndex(selectedIndex);
 	$: watchEntries(entries);
@@ -113,15 +115,49 @@
 		const blurTarget = (e.target instanceof Element ? e.target.closest("[data-dropdown-input]") : undefined) || undefined;
 		if (blurTarget !== self?.div?.()) open = false;
 	}
+
+	function takesDraggedFile(e: DragEvent): boolean {
+		return Boolean(fileDropAction) && !disabled && Boolean(e.dataTransfer?.types.includes("Files"));
+	}
+
+	function fileDragOverWidget(e: DragEvent) {
+		if (!takesDraggedFile(e)) return;
+
+		// The browser refuses the drop unless the dragover is canceled
+		e.preventDefault();
+		fileDragOver = true;
+	}
+
+	function fileDragLeaveWidget(e: DragEvent) {
+		// Moving between the widget's own children is not leaving it
+		if (e.relatedTarget instanceof Node && self?.div?.()?.contains(e.relatedTarget)) return;
+
+		fileDragOver = false;
+	}
+
+	function fileDropOnWidget(e: DragEvent) {
+		if (!takesDraggedFile(e)) return;
+
+		// The drop is kept from also reaching a panel that imports dropped files
+		e.preventDefault();
+		e.stopPropagation();
+		fileDragOver = false;
+
+		const file = e.dataTransfer?.files[0];
+		if (file) dispatch("fileDrop", file);
+	}
 </script>
 
 <LayoutRow
 	class="dropdown-input"
-	classes={{ narrow }}
+	classes={{ narrow, "file-drag-over": fileDragOver }}
 	styles={{
 		...(minWidth > 0 ? { "min-width": `${minWidth}px` } : {}),
 		...(maxWidth > 0 ? { "max-width": `${maxWidth}px` } : {}),
 	}}
+	on:dragover={fileDragOverWidget}
+	on:dragleave={fileDragLeaveWidget}
+	on:drop={fileDropOnWidget}
 	bind:this={self}
 	data-dropdown-input
 >
@@ -169,6 +205,15 @@
 			--widget-height: 20px;
 		}
 
+		&.file-drag-over::after {
+			content: "";
+			position: absolute;
+			inset: -4px;
+			border: 1px dashed var(--color-e-nearwhite);
+			border-radius: 4px;
+			pointer-events: none;
+		}
+
 		.dropdown-box {
 			align-items: center;
 			white-space: nowrap;

frontend/wrapper/src/editor_commands.rs

@@ -597,7 +597,7 @@ mod editor_commands {
 		ClipboardMessage::ReadSelection { content, cut }.into()
 	}
 
-	/// A file picked in the dialog that `TriggerBrowse` opened
+	/// A file headed for a known action, either picked in the dialog that `TriggerBrowse` opened or dropped onto a widget that takes files
 	fn ingest_picked(name: String, mime_type: String, data: Vec<u8>, action: IngestAction) -> Message {
 		IngestMessage::Ingest {
 			data,