feat: workspace helpers - quoting paths, what a dropped file does, with node tests

internal/server/web/static/wsutil.js

@@ -0,0 +1,27 @@
+// Pure helpers of the workspace: quoting paths for a shell, what a dropped
+// file does where it lands, sizes. No DOM here, so node can test them.
+(function (root) {
+  'use strict';
+  function shellQuote(p) { return "'" + String(p).replace(/'/g, "'\\''") + "'"; }
+  function shellQuoteAll(ps) { return ps.map(shellQuote).join(' '); }
+  const same = (a, b) => a.kind === b.kind && a.id === b.id;
+  // dropAction says what dropping item on target does: a transfer between
+  // file panes, paths pasted into a terminal of the same place, nothing on
+  // its own folder, or a refusal with the reason.
+  function dropAction(item, target) {
+    if (target.kind === 'term') {
+      return same(item.source, target.source) ? {kind: 'paste'}
+        : {kind: 'deny', reason: 'Нельзя: файл на ' + item.source.label + ', а терминал на ' + target.source.label};
+    }
+    if (same(item.source, target.source) && target.dir === item.dir) return {kind: 'none'};
+    return {kind: 'transfer'};
+  }
+  function fmtSize(n) {
+    if (n < 1024) return n + ' B';
+    if (n < 1048576) return (n / 1024).toFixed(1) + ' K';
+    if (n < 1073741824) return (n / 1048576).toFixed(1) + ' M';
+    return (n / 1073741824).toFixed(1) + ' G';
+  }
+  const api = {shellQuote, shellQuoteAll, dropAction, fmtSize};
+  if (typeof module !== 'undefined') module.exports = api; else root.WSUtil = api;
+})(this);