refactor: replace detectClipboard with try-fallback-cached clipboard strategy

- Remove detectClipboard Process and clipboardCmd property
- Add try-fallback-cached copy logic: attempt cached tool first,
  then cycle through hardcoded safe tools (dms, wl-copy, clipmanctl)
- Add stderr StdioCollector to all Process components for error details
- Update lib.js: replace parseClipboardDetection with validateClipboardTool,
  buildCopyCommand, nextClipboardTool, allClipboardTools
- Update tests to match new lib.js API

Benefits:
- No startup delay from clipboard detection process
- Robust fallback if clipboard tool becomes unavailable
- Better error messages with stderr details from failed commands

tailscalectl/TailscaleWidget.qml

@@ -15,7 +15,10 @@ PluginComponent {
     property string tailscaleIP: ""
     property string currentExitNode: ""
     property var peers: []
-    property string clipboardCmd: ""
+    property string cachedClipboardTool: ""
+    property string _copyText: ""
+    property string _copyCurrentTool: ""
+    property int _copyAttempted: 0
 
     layerNamespacePlugin: "tailscalectl"
     popoutWidth: 360
@@ -29,16 +32,19 @@ PluginComponent {
     }
 
     Component.onCompleted: {
-        detectClipboard.running = true
+        statusCheck.running = true
     }
 
     Process {
         id: toggleProcess
 
+        stderr: StdioCollector {}
+
         onExited: (code, status) => {
             if (code !== 0) {
                 var action = root.isConnected ? "disconnect" : "connect"
-                ToastService.showError("tailscalectl", TailscaleLib.errorMessage(action))
+                var detail = toggleProcess.stderr.text.trim().slice(0, 120)
+                ToastService.showError("tailscalectl", TailscaleLib.errorMessage(action) + (detail ? " — " + detail : ""))
             }
             statusCheck.running = true
         }
@@ -46,35 +52,40 @@ PluginComponent {
 
     Process {
         id: copyProcess
+
+        stderr: StdioCollector {}
+
+        onExited: (code, status) => {
+            if (code === 0) {
+                root.cachedClipboardTool = root._copyCurrentTool
+                ToastService.showInfo("Copied " + root._copyText + " to clipboard")
+            } else {
+                root._copyAttempted += 1
+                if (root._copyAttempted < TailscaleLib.allClipboardTools().length) {
+                    root._copyCurrentTool = TailscaleLib.nextClipboardTool(root._copyCurrentTool)
+                    root._executeCopy()
+                } else {
+                    var detail = copyProcess.stderr.text.trim().slice(0, 120)
+                    ToastService.showError("tailscalectl", "No clipboard tool found" + (detail ? " — " + detail : ""))
+                }
+            }
+        }
     }
 
     Process {
         id: exitNodeProcess
 
+        stderr: StdioCollector {}
+
         onExited: (code, status) => {
             if (code !== 0) {
-                ToastService.showError("tailscalectl", TailscaleLib.errorMessage("set"))
+                var detail = exitNodeProcess.stderr.text.trim().slice(0, 120)
+                ToastService.showError("tailscalectl", TailscaleLib.errorMessage("set") + (detail ? " — " + detail : ""))
             }
             statusCheck.running = true
         }
     }
 
-    Process {
-        id: detectClipboard
-
-        command: ["sh", "-c", "if which dms >/dev/null 2>&1; then echo 'dms cl copy'; elif which wl-copy >/dev/null 2>&1; then echo 'wl-copy'; elif which clipmanctl >/dev/null 2>&1; then echo 'clipmanctl copy'; elif which xclip >/dev/null 2>&1; then echo 'xclip -selection clipboard'; elif which xsel >/dev/null 2>&1; then echo 'xsel --clipboard --input'; else echo none; fi"]
-
-        stdout: StdioCollector {
-            onStreamFinished: {
-                root.clipboardCmd = TailscaleLib.parseClipboardDetection(this.text)
-            }
-        }
-
-        onExited: (code, status) => {
-            statusCheck.running = true
-        }
-    }
-
     Process {
         id: statusCheck
 
@@ -125,18 +136,24 @@ PluginComponent {
     }
 
     function copyToClipboard(text) {
-        if (!root.clipboardCmd || root.clipboardCmd === "none") {
+        root._copyText = text
-            ToastService.showError("tailscalectl", "No clipboard tool found")
+        root._copyAttempted = 0
-            return
+        if (root.cachedClipboardTool) {
+            root._copyCurrentTool = root.cachedClipboardTool
+        } else {
+            root._copyCurrentTool = TailscaleLib.allClipboardTools()[0]
         }
-        var cmd = TailscaleLib.buildCopyCommand(text, root.clipboardCmd)
+        root._executeCopy()
+    }
+
+    function _executeCopy() {
+        var cmd = TailscaleLib.buildCopyCommand(root._copyText, root._copyCurrentTool)
         if (!cmd) {
             ToastService.showError("tailscalectl", "Invalid clipboard command")
             return
         }
         copyProcess.command = cmd
         copyProcess.running = true
-        ToastService.showInfo("Copied " + text + " to clipboard")
     }
 
     popoutContent: Component {

tailscalectl/lib.js

@@ -26,16 +26,34 @@ function findActiveExitNode(peerMap) {
     return ""
 }
 
-var safeClipboardCmds = ["dms cl copy", "wl-copy", "clipmanctl copy", "xclip -selection clipboard", "xsel --clipboard --input", "none"]
+var safeClipboardTools = ["dms", "wl-copy", "clipmanctl"]
 
-function validateClipboardCmd(cmd) {
+var clipboardCmdMap = {
-    return typeof cmd === "string" && safeClipboardCmds.includes(cmd)
+    "dms": "dms cl copy",
+    "wl-copy": "wl-copy",
+    "clipmanctl": "clipmanctl copy"
 }
 
-function buildCopyCommand(text, clipboardCmd) {
+function validateClipboardTool(tool) {
-    if (!validateClipboardCmd(clipboardCmd)) return null
+    return typeof tool === "string" && safeClipboardTools.includes(tool)
+}
+
+function buildCopyCommand(text, tool) {
+    if (!validateClipboardTool(tool)) return null
+    var cmd = clipboardCmdMap[tool]
+    if (!cmd) return null
     var escaped = text.replace(/'/g, "'\\''")
-    return ["sh", "-c", "printf '%s' '" + escaped + "' | " + clipboardCmd]
+    return ["sh", "-c", "printf '%s' '" + escaped + "' | " + cmd]
+}
+
+function nextClipboardTool(currentTool) {
+    var idx = safeClipboardTools.indexOf(currentTool)
+    if (idx < 0) return safeClipboardTools[0]
+    return safeClipboardTools[(idx + 1) % safeClipboardTools.length]
+}
+
+function allClipboardTools() {
+    return safeClipboardTools.slice()
 }
 
 function parseStatusResult(jsonText) {
@@ -56,11 +74,6 @@ function buildToggleCommand(isConnected) {
     return isConnected ? ["tailscale", "down"] : ["tailscale", "up"]
 }
 
-function parseClipboardDetection(stdout) {
-    var trimmed = typeof stdout === "string" ? stdout.trim() : ""
-    return validateClipboardCmd(trimmed) ? trimmed : "none"
-}
-
 function errorMessage(cmd) {
     var messages = {
         "up": "Failed to connect to Tailscale",
@@ -75,5 +88,5 @@ function errorMessage(cmd) {
 
 // CommonJS export for Node.js tests (ignored by QML)
 if (typeof module !== "undefined" && module.exports) {
-    module.exports = { parsePeers, makeExitNodeCommand, findActiveExitNode, errorMessage, validateClipboardCmd, buildCopyCommand, parseClipboardDetection, buildToggleCommand, parseStatusResult }
+    module.exports = { parsePeers, makeExitNodeCommand, findActiveExitNode, errorMessage, validateClipboardTool, buildCopyCommand, nextClipboardTool, allClipboardTools, buildToggleCommand, parseStatusResult }
 }

test/lib.test.js

@@ -1,7 +1,7 @@
 import { test } from "node:test"
 import assert from "node:assert"
 import lib from "../tailscalectl/lib.js"
-const { parsePeers, makeExitNodeCommand, findActiveExitNode, errorMessage, validateClipboardCmd, buildCopyCommand, parseClipboardDetection, buildToggleCommand, parseStatusResult } = lib
+const { parsePeers, makeExitNodeCommand, findActiveExitNode, errorMessage, validateClipboardTool, buildCopyCommand, nextClipboardTool, allClipboardTools, buildToggleCommand, parseStatusResult } = lib
 
 test("parsePeers extracts exitNode from ExitNodeOption", () => {
     const peerMap = {
@@ -75,28 +75,25 @@ test("errorMessage returns generic message for unknown command", () => {
     assert.strictEqual(msg, "Tailscale command failed")
 })
 
-// --- validateClipboardCmd ---
+// --- validateClipboardTool ---
 
-test("validateClipboardCmd accepts whitelisted values", () => {
+test("validateClipboardTool accepts whitelisted tool names", () => {
-    assert.strictEqual(validateClipboardCmd("dms cl copy"), true)
+    assert.strictEqual(validateClipboardTool("dms"), true)
-    assert.strictEqual(validateClipboardCmd("wl-copy"), true)
+    assert.strictEqual(validateClipboardTool("wl-copy"), true)
-    assert.strictEqual(validateClipboardCmd("clipmanctl copy"), true)
+    assert.strictEqual(validateClipboardTool("clipmanctl"), true)
-    assert.strictEqual(validateClipboardCmd("xclip -selection clipboard"), true)
-    assert.strictEqual(validateClipboardCmd("xsel --clipboard --input"), true)
-    assert.strictEqual(validateClipboardCmd("none"), true)
 })
 
-test("validateClipboardCmd rejects malicious inputs", () => {
+test("validateClipboardTool rejects malicious inputs", () => {
-    assert.strictEqual(validateClipboardCmd("rm -rf /"), false)
+    assert.strictEqual(validateClipboardTool("rm -rf /"), false)
-    assert.strictEqual(validateClipboardCmd("echo hi; malicious"), false)
+    assert.strictEqual(validateClipboardTool("echo hi; malicious"), false)
-    assert.strictEqual(validateClipboardCmd("$(whoami)"), false)
+    assert.strictEqual(validateClipboardTool("$(whoami)"), false)
-    assert.strictEqual(validateClipboardCmd("wl-copy || rm -rf /"), false)
+    assert.strictEqual(validateClipboardTool("wl-copy || rm -rf /"), false)
 })
 
-test("validateClipboardCmd rejects empty and falsy inputs", () => {
+test("validateClipboardTool rejects empty and falsy inputs", () => {
-    assert.strictEqual(validateClipboardCmd(""), false)
+    assert.strictEqual(validateClipboardTool(""), false)
-    assert.strictEqual(validateClipboardCmd(null), false)
+    assert.strictEqual(validateClipboardTool(null), false)
-    assert.strictEqual(validateClipboardCmd(undefined), false)
+    assert.strictEqual(validateClipboardTool(undefined), false)
 })
 
 // --- buildCopyCommand ---
@@ -108,7 +105,7 @@ test("buildCopyCommand returns safe command for whitelisted clipboard tool", ()
     assert.strictEqual(cmd[1], "-c")
 })
 
-test("buildCopyCommand returns null for invalid clipboard command", () => {
+test("buildCopyCommand returns null for invalid clipboard tool", () => {
     assert.strictEqual(buildCopyCommand("hello", "rm -rf /"), null)
     assert.strictEqual(buildCopyCommand("hello", ""), null)
     assert.strictEqual(buildCopyCommand("hello", null), null)
@@ -119,31 +116,28 @@ test("buildCopyCommand safely handles text with special characters", () => {
     assert.ok(Array.isArray(cmd))
 })
 
-// --- parseClipboardDetection ---
+// --- nextClipboardTool ---
 
-test("parseClipboardDetection passes through expected output strings", () => {
+test("nextClipboardTool cycles through tools", () => {
-    assert.strictEqual(parseClipboardDetection("dms cl copy"), "dms cl copy")
+    assert.strictEqual(nextClipboardTool("dms"), "wl-copy")
-    assert.strictEqual(parseClipboardDetection("wl-copy"), "wl-copy")
+    assert.strictEqual(nextClipboardTool("wl-copy"), "clipmanctl")
-    assert.strictEqual(parseClipboardDetection("clipmanctl copy"), "clipmanctl copy")
+    assert.strictEqual(nextClipboardTool("clipmanctl"), "dms")
-    assert.strictEqual(parseClipboardDetection("none"), "none")
 })
 
-test("parseClipboardDetection trims extra whitespace", () => {
+test("nextClipboardTool falls back to first tool for unknown input", () => {
-    assert.strictEqual(parseClipboardDetection("  wl-copy  \n"), "wl-copy")
+    assert.strictEqual(nextClipboardTool(""), "dms")
+    assert.strictEqual(nextClipboardTool("unknown"), "dms")
 })
 
-test("parseClipboardDetection falls back to none for multi-line output", () => {
+// --- allClipboardTools ---
-    assert.strictEqual(parseClipboardDetection("wl-copy\nrm -rf /"), "none")
-})
 
-test("parseClipboardDetection falls back to empty output", () => {
+test("allClipboardTools returns the list of safe tools", () => {
-    assert.strictEqual(parseClipboardDetection(""), "none")
+    const tools = allClipboardTools()
-    assert.strictEqual(parseClipboardDetection("   "), "none")
+    assert.ok(Array.isArray(tools))
-})
+    assert.strictEqual(tools.length, 3)
-
+    assert.ok(tools.includes("dms"))
-test("parseClipboardDetection falls back to none for unexpected strings", () => {
+    assert.ok(tools.includes("wl-copy"))
-    assert.strictEqual(parseClipboardDetection("pbpaste"), "none")
+    assert.ok(tools.includes("clipmanctl"))
-    assert.strictEqual(parseClipboardDetection("custom-tool"), "none")
 })
 
 // --- buildToggleCommand ---