Allow bulk downloading selection

svelte/src/filesystem/FSNavigator.ts

@@ -1,5 +1,5 @@
 import { loading_finish, loading_run, loading_start } from "lib/Loading";
-import { fs_get_node, fs_encode_path, fs_split_path, fs_path_from_json, fs_rename } from "lib/FilesystemAPI.svelte";
+import { fs_get_node, fs_encode_path, fs_split_path, fs_path_from_json, fs_path_url, fs_rename } from "lib/FilesystemAPI.svelte";
 import type { FSNode, FSPath, FSPermissions, FSContext } from "lib/FilesystemAPI.svelte";
 
 export class FSNavigator {
@@ -286,6 +286,27 @@ export class FSNavigator {
 		this.set_selecting(true)
 	}
 
+	// Downloads the selection, or the open node if nothing is selected. More
+	// than one node is zipped by the closest directory which they are all in
+	download = () => {
+		const nodes = [...this.selection.values()]
+		if (nodes.length < 2) {
+			return (nodes[0] ?? this.base).download()
+		}
+
+		let dir = nodes[0].path
+		do {
+			dir = dir.slice(0, dir.lastIndexOf("/"))
+		} while (!nodes.every(n => n.path.startsWith(dir + "/")))
+
+		const a = document.createElement("a")
+		a.href = fs_path_url(dir) + "?bulk_download&" + new URLSearchParams(
+			nodes.map(n => ["include", n.path.slice(dir.length + 1)])
+		)
+		a.download = ""
+		a.dispatchEvent(new MouseEvent("click"))
+	}
+
 	// A directory can't be moved into itself, and there has to be at least one
 	// node which is not in dir already
 	can_move = (dir: string) => {

svelte/src/filesystem/Filesystem.svelte

@@ -84,7 +84,7 @@ const keydown = (e: KeyboardEvent) => {
 			}
 			break;
 		case "s":
-			nav.base.download()
+			nav.download()
 			break;
 		case "r":
 			nav.shuffle = !nav.shuffle

svelte/src/filesystem/Toolbar.svelte

@@ -52,7 +52,7 @@ export const copy_link = () => {
 			</button>
 		</div>
 
-		<button onclick={() => $nav.base.download()}>
+		<button onclick={() => nav.download()}>
 			<i class="icon">save</i>
 			<span>Download</span>
 		</button>