fix(cua-driver-rs)(windows): cua-driver autostart enable self-elevates for RunLevel=Highest

libs/cua-driver-rs/crates/cua-driver/src/autostart.rs

@@ -162,43 +162,84 @@ Register-ScheduledTask -TaskName 'cua-driver-serve' -Action $action -Trigger $tr
 "#;
 
     pub fn enable(exe: &str) -> Result<()> {
-        // Pass the binary path via env var so the script doesn't need
-        // shell-quoting acrobatics for paths with spaces or odd chars.
+        // First attempt: register directly. Works when called from an
+        // already-elevated context (install.ps1's self-elevated child shell,
+        // or a user running cua-driver autostart enable from an admin
+        // PowerShell). Pass the binary path via env var so the script
+        // doesn't need shell-quoting acrobatics for paths with spaces.
         let out = Command::new("powershell")
             .args(["-NoProfile", "-NonInteractive", "-Command", REGISTER_PS])
             .env("CUA_DRIVER_AS_EXE", exe)
             .output()
             .map_err(|e| anyhow!("failed to invoke powershell: {e}"))?;
-        if !out.status.success() {
-            let stderr = String::from_utf8_lossy(&out.stderr);
-            // Detect the most common cause — non-elevated caller can't
-            // register a RunLevel=Highest task — and surface an actionable
-            // message instead of the raw PowerShell stack trace.
-            let stderr_lower = stderr.to_lowercase();
-            let looks_like_access_denied = stderr_lower.contains("access is denied")
-                || stderr_lower.contains("0x80070005")
-                || stderr_lower.contains("permission")
-                || stderr_lower.contains("requires elevation");
-            if looks_like_access_denied {
-                return Err(anyhow!(
-                    "Register-ScheduledTask failed: this task is registered with \
-                     RunLevel=Highest so the daemon can drive UWP / AppContainer apps \
-                     (Calculator, modern Settings, Photos, ...). Registering a Highest \
-                     task itself requires admin. Re-run from an elevated PowerShell, or \
-                     run install.ps1 with -AutoStart from an elevated session. See \
-                     https://github.com/trycua/cua/issues/1602 for context.\n\
-                     \n\
-                     Raw error: {}",
-                    stderr.trim()
-                ));
-            }
+        if out.status.success() {
+            return Ok(());
+        }
+
+        let stderr = String::from_utf8_lossy(&out.stderr);
+        let stderr_lower = stderr.to_lowercase();
+        let looks_like_access_denied = stderr_lower.contains("access is denied")
+            || stderr_lower.contains("0x80070005")
+            || stderr_lower.contains("permission")
+            || stderr_lower.contains("requires elevation");
+
+        if !looks_like_access_denied {
             return Err(anyhow!(
                 "PowerShell Register-ScheduledTask failed (exit {}): {}",
                 out.status.code().unwrap_or(-1),
                 stderr.trim()
             ));
         }
-        Ok(())
+
+        // Access-denied — caller is at Medium IL but the task wants Highest.
+        // Self-elevate via ShellExecute "runas" verb, which fires the UAC
+        // prompt. The elevated child runs the same registration via
+        // powershell -Command, with the registered binary path injected as
+        // an env var (durable across the elevation boundary).
+        eprintln!("cua-driver: registering autostart at RunLevel=Highest needs admin.");
+        eprintln!("cua-driver: triggering UAC prompt — accept it to register the task.");
+
+        let elevated_status = {
+            use std::os::windows::process::CommandExt;
+            // CREATE_NO_WINDOW = 0x08000000 — keep the elevated child's
+            // console out of the foreground; PowerShell already runs hidden
+            // via Start-Process -Verb RunAs's WindowStyle Hidden.
+            const CREATE_NO_WINDOW: u32 = 0x08000000;
+
+            // PowerShell incantation: Start-Process -Verb RunAs to elevate,
+            // run our own exe with `autostart enable` so the registration
+            // happens INSIDE the elevated process (where it'll succeed on
+            // the first attempt and not re-enter this branch). -Wait so we
+            // can capture the child's exit code.
+            let inner = format!(
+                "& \"{}\" autostart enable",
+                exe.replace('"', "`\"")
+            );
+            let outer = format!(
+                "$p = Start-Process -FilePath '{}' -ArgumentList @('-NoProfile','-NonInteractive','-Command',{}) -Verb RunAs -Wait -PassThru; exit $p.ExitCode",
+                "powershell.exe",
+                // Embed the inner command as a single-quoted PowerShell string
+                // (PS escapes ' as '' inside ''-strings).
+                format!("'{}'", inner.replace('\'', "''"))
+            );
+            Command::new("powershell")
+                .args(["-NoProfile", "-NonInteractive", "-Command", &outer])
+                .creation_flags(CREATE_NO_WINDOW)
+                .status()
+                .map_err(|e| anyhow!("failed to spawn elevation helper: {e}"))?
+        };
+
+        if elevated_status.success() {
+            Ok(())
+        } else {
+            Err(anyhow!(
+                "self-elevation for autostart registration failed (exit {}). The UAC \
+                 prompt was probably dismissed. Re-run `cua-driver autostart enable` \
+                 and accept the prompt, or run install.ps1 -AutoStart which has the \
+                 same self-elevation flow. See https://github.com/trycua/cua/issues/1602.",
+                elevated_status.code().unwrap_or(-1)
+            ))
+        }
     }
 
     pub fn disable() -> Result<()> {