feat: Drag & drop to import new books

src/components/organisms/Sidebar.tsx

@@ -25,6 +25,8 @@ import {
 	title as addBookFormTitle,
 } from "../molecules/AddBookForm";
 import { SwitchLibraryForm } from "../molecules/SwitchLibraryForm";
+import { appWindow } from "@tauri-apps/api/window";
+import { addBookByDragDrop } from "@/lib/services/library/_internal/addBook";
 
 export const Sidebar = () => {
 	const { library, state, eventEmitter } = useLibrary();
@@ -45,6 +47,38 @@ export const Sidebar = () => {
 		{ close: closeSwitchLibraryModal, open: openSwitchLibraryModal },
 	] = useDisclosure(false);
 
+	useEffect(() => {
+		let unlisten: (() => void) | undefined;
+
+		const setupFileDropListener = async () => {
+			unlisten = await appWindow.onFileDropEvent((event) => {
+				if (!library) return;
+
+				void (async () => {
+					if (event.payload.type === "drop") {
+						const metadataList = await addBookByDragDrop(
+							library,
+							event.payload.paths,
+						);
+						const firstItem = metadataList[0];
+						if (firstItem) {
+							setMetadata(firstItem);
+							openAddBookModal();
+						}
+					}
+				})();
+			});
+		};
+
+		void setupFileDropListener();
+
+		return () => {
+			if (unlisten) {
+				unlisten();
+			}
+		};
+	}, [library, openAddBookModal]);
+
 	useEffect(() => {
 		void (async () => {
 			setAuthorList(

src/lib/services/library/_internal/addBook.ts

@@ -5,6 +5,27 @@ import { EventEmitter } from "@/lib/event";
 import { dialog } from "@tauri-apps/api";
 import type { Library } from "./_types";
 
+export const addBookByDragDrop = async (
+	library: Library,
+	paths: string[],
+): Promise<ImportableBookMetadata[]> => {
+	const importableMetadata = [];
+	for (const path of paths) {
+		const importableFile = await library.checkFileImportable(path);
+		if (!importableFile) {
+			continue;
+		}
+		const metadata = await library.getImportableFileMetadata(importableFile);
+		if (!metadata) {
+			continue;
+		}
+
+		importableMetadata.push(metadata);
+	}
+
+	return importableMetadata;
+};
+
 export const promptToAddBook = async (
 	library: Library,
 ): Promise<ImportableBookMetadata | undefined> => {