feat(tui): add /app desktop handoff (#25638)

codex-rs/tui/src/app/event_dispatch.rs

@@ -403,6 +403,9 @@ impl App {
             AppEvent::OpenUrlInBrowser { url } => {
                 self.open_url_in_browser(url);
             }
+            AppEvent::OpenDesktopThread { thread_id } => {
+                self.open_desktop_thread(thread_id);
+            }
             AppEvent::PetSelected { pet_id } => {
                 self.handle_pet_selected(tui, pet_id);
             }

codex-rs/tui/src/app/history_ui.rs

@@ -1,10 +1,12 @@
-//! Terminal history and clear-screen UI helpers for the TUI app.
+//! Terminal history, desktop handoff, and clear-screen UI helpers for the TUI app.
 //!
 //! This module owns rendering the fresh session header, clearing inline or alternate-screen UI
 //! state, and resetting transcript-related app state after `/clear` or Ctrl-L.
 
 use super::*;
 
+const DESKTOP_THREAD_OPENED_MESSAGE: &str = "Opened this session in Codex Desktop.";
+
 impl App {
     pub(super) fn open_url_in_browser(&mut self, url: String) {
         if let Err(err) = webbrowser::open(&url) {
@@ -17,6 +19,20 @@ impl App {
             .add_info_message(format!("Opened {url} in your browser."), /*hint*/ None);
     }
 
+    pub(super) fn open_desktop_thread(&mut self, thread_id: ThreadId) {
+        let url = format!("codex://threads/{thread_id}");
+        if let Err(err) = open_desktop_thread_url(&url) {
+            self.chat_widget
+                .add_error_message(desktop_thread_open_error_message(&err));
+            return;
+        }
+
+        self.chat_widget.add_info_message(
+            DESKTOP_THREAD_OPENED_MESSAGE.to_string(),
+            /*hint*/ None,
+        );
+    }
+
     pub(super) fn clear_ui_header_lines_with_version(
         &self,
         width: u16,
@@ -99,3 +115,93 @@ impl App {
         self.backtrack_render_pending = false;
     }
 }
+
+fn desktop_thread_open_error_message(err: &str) -> String {
+    format!(
+        "Failed to open this session in Codex Desktop: {err}. Install or launch Codex Desktop and try again."
+    )
+}
+
+#[cfg(target_os = "macos")]
+fn open_desktop_thread_url(url: &str) -> Result<(), String> {
+    let status = std::process::Command::new("open")
+        .arg(url)
+        .status()
+        .map_err(|err| format!("failed to invoke `open`: {err}"))?;
+
+    if status.success() {
+        Ok(())
+    } else {
+        Err(format!("`open {url}` exited with {status}"))
+    }
+}
+
+#[cfg(target_os = "windows")]
+fn open_desktop_thread_url(url: &str) -> Result<(), String> {
+    let script = windows_desktop_app_launch_script(url);
+    let output = std::process::Command::new("powershell.exe")
+        .arg("-NoProfile")
+        .arg("-Command")
+        .arg(&script)
+        .output()
+        .map_err(|err| format!("failed to launch Codex Desktop through PowerShell: {err}"))?;
+
+    if output.status.success() {
+        return Ok(());
+    }
+
+    let stderr = String::from_utf8_lossy(&output.stderr).trim().to_string();
+    if stderr.is_empty() {
+        Err(format!(
+            "failed to launch Codex Desktop through PowerShell with {}",
+            output.status
+        ))
+    } else {
+        Err(stderr)
+    }
+}
+
+#[cfg(target_os = "windows")]
+fn windows_desktop_app_launch_script(url: &str) -> String {
+    let url = powershell_single_quoted_string(url);
+    format!(
+        r#"
+$ErrorActionPreference = 'Stop'
+$url = {url}
+
+$installLocation = (Get-AppxPackage -Name OpenAI.Codex -ErrorAction SilentlyContinue).InstallLocation
+if ([string]::IsNullOrWhiteSpace($installLocation)) {{
+    Write-Error 'Codex Desktop package is not installed'
+    exit 1
+}}
+
+$appDir = Join-Path $installLocation 'app'
+$exe = Join-Path $appDir 'Codex.exe'
+$app = Join-Path $appDir 'resources\app.asar'
+if (-not (Test-Path $exe)) {{
+    Write-Error "Codex Desktop executable not found at $exe"
+    exit 1
+}}
+if (-not (Test-Path $app)) {{
+    Write-Error "Codex Desktop app bundle not found at $app"
+    exit 1
+}}
+
+Start-Process -FilePath $exe -WorkingDirectory $appDir -ArgumentList @('resources\app.asar', $url)
+"#
+    )
+}
+
+#[cfg(target_os = "windows")]
+fn powershell_single_quoted_string(value: &str) -> String {
+    format!("'{}'", value.replace('\'', "''"))
+}
+
+#[cfg(not(any(target_os = "macos", target_os = "windows")))]
+fn open_desktop_thread_url(_url: &str) -> Result<(), String> {
+    Err("Codex Desktop is only available on macOS and Windows".to_string())
+}
+
+#[cfg(test)]
+#[path = "history_ui_tests.rs"]
+mod tests;

codex-rs/tui/src/app/history_ui_tests.rs

@@ -0,0 +1,29 @@
+use super::*;
+use crate::history_cell;
+use crate::history_cell::HistoryCell;
+
+#[test]
+fn desktop_thread_opened_history_snapshot() {
+    let cell = history_cell::new_info_event(
+        DESKTOP_THREAD_OPENED_MESSAGE.to_string(),
+        /*hint*/ None,
+    );
+
+    insta::assert_snapshot!("desktop_thread_opened_history", render_cell(&cell));
+}
+
+#[test]
+fn desktop_thread_open_error_history_snapshot() {
+    let cell = history_cell::new_error_event(desktop_thread_open_error_message("launch failed"));
+
+    insta::assert_snapshot!("desktop_thread_open_error_history", render_cell(&cell));
+}
+
+fn render_cell(cell: &impl HistoryCell) -> String {
+    let lines = cell.display_lines(/*width*/ 80);
+    lines
+        .iter()
+        .map(ToString::to_string)
+        .collect::<Vec<_>>()
+        .join("\n")
+}

codex-rs/tui/src/app/snapshots/codex_tui__app__history_ui__tests__desktop_thread_open_error_history.snap

@@ -0,0 +1,5 @@
+---
+source: tui/src/app/history_ui_tests.rs
+expression: render_cell(&cell)
+---
+■ Failed to open this session in Codex Desktop: launch failed. Install or launch Codex Desktop and try again.

codex-rs/tui/src/app/snapshots/codex_tui__app__history_ui__tests__desktop_thread_opened_history.snap

@@ -0,0 +1,5 @@
+---
+source: tui/src/app/history_ui_tests.rs
+expression: render_cell(&cell)
+---
+• Opened this session in Codex Desktop.