feat: terminal copy and paste by keys off a Mac - Ctrl+C copies a selection (interrupts without one), Ctrl+Shift+C copies and stays from the browser, Ctrl+V and Ctrl+Shift+V paste

internal/server/web/static/terminal.js

@@ -28,6 +28,49 @@
     return u;
   }
 
+  // ---------- copy and paste by keys ----------
+  // Off a Mac, where Cmd does it, Ctrl+C copies when there is a selection and
+  // interrupts as ever when there is none; Ctrl+Shift+C always copies (and is
+  // kept from the browser, whose developer tools it would open); Ctrl+V and
+  // Ctrl+Shift+V paste. Keys go by position, so a Russian layout works too.
+  const mac = /Mac|iPhone|iPad/.test(navigator.platform || navigator.userAgent);
+  function copyText(text) {
+    if (navigator.clipboard && window.isSecureContext) return navigator.clipboard.writeText(text);
+    // Plain http: the old way, through a field that is there for a moment.
+    const ta = document.createElement('textarea'), back = document.activeElement;
+    ta.value = text;
+    ta.style.cssText = 'position:fixed;top:0;left:0;opacity:0';
+    document.body.appendChild(ta);
+    ta.select();
+    const ok = document.execCommand('copy');
+    ta.remove();
+    if (back && back.focus) back.focus();
+    return ok ? Promise.resolve() : Promise.reject(new Error('нет доступа к буферу'));
+  }
+  function clipKeys(s, ev) {
+    if (mac || !ev.ctrlKey || ev.altKey || ev.metaKey) return true;
+    const c = ev.code === 'KeyC', v = ev.code === 'KeyV';
+    if (!c && !v) return true;
+    if (c && !ev.shiftKey && !s.term.hasSelection()) return true; // ^C to the shell
+    // From here the key is ours: xterm does not turn it into a control code.
+    if (ev.type === 'keydown' && c) {
+      ev.preventDefault();
+      if (s.term.hasSelection()) {
+        const text = s.term.getSelection();
+        s.term.clearSelection();
+        copyText(text).then(() => flashStatus('скопировано', 'st-ok'), e => flashStatus('не скопировалось: ' + e.message, 'st-err'));
+      }
+    }
+    // Ctrl+V: the browser's paste goes on into the terminal's text field.
+    return false;
+  }
+  function flashStatus(t, cls) {
+    statusEl.textContent = t;
+    statusEl.className = cls;
+    clearTimeout(flashStatus.t);
+    flashStatus.t = setTimeout(showStatus, 1500);
+  }
+
   // ---------- one shell ----------
   class Session {
     // ssh, when given, is where the agent connects by SSH for this shell:
@@ -53,6 +96,7 @@
       this.fitter = new FitAddon.FitAddon();
       this.term.loadAddon(this.fitter);
       this.term.open(this.el.querySelector('.pane-body'));
+      this.term.attachCustomKeyEventHandler(ev => clipKeys(this, ev));
       this.term.onData(d => this.send(TermKeys.withMods(d)));
       this.term.onResize(() => this.queueIn({ t: 'r', cols: this.term.cols, rows: this.term.rows }));
       this.term.onSelectionChange(() => TermKeys.selectionChanged(this));