Move TUI on top of app server (parallel code) (#14717)

This PR replicates the `tui` code directory and creates a temporary
parallel `tui_app_server` directory. It also implements a new feature
flag `tui_app_server` to select between the two tui implementations.

Once the new app-server-based TUI is stabilized, we'll delete the old
`tui` directory and feature flag.

codex-rs/tui/src/app_server_tui_dispatch.rs

@@ -0,0 +1,45 @@
+use std::future::Future;
+
+use crate::Cli;
+use codex_core::config::Config;
+use codex_core::config::ConfigOverrides;
+use codex_core::features::Feature;
+
+pub(crate) fn app_server_tui_config_inputs(
+    cli: &Cli,
+) -> std::io::Result<(Vec<(String, toml::Value)>, ConfigOverrides)> {
+    let mut raw_overrides = cli.config_overrides.raw_overrides.clone();
+    if cli.web_search {
+        raw_overrides.push("web_search=\"live\"".to_string());
+    }
+
+    let cli_kv_overrides = codex_utils_cli::CliConfigOverrides { raw_overrides }
+        .parse_overrides()
+        .map_err(|err| std::io::Error::new(std::io::ErrorKind::InvalidInput, err))?;
+
+    let config_overrides = ConfigOverrides {
+        cwd: cli.cwd.clone(),
+        config_profile: cli.config_profile.clone(),
+        ..Default::default()
+    };
+
+    Ok((cli_kv_overrides, config_overrides))
+}
+
+pub(crate) async fn should_use_app_server_tui_with<F, Fut>(
+    cli: &Cli,
+    load_config: F,
+) -> std::io::Result<bool>
+where
+    F: FnOnce(Vec<(String, toml::Value)>, ConfigOverrides) -> Fut,
+    Fut: Future<Output = std::io::Result<Config>>,
+{
+    let (cli_kv_overrides, config_overrides) = app_server_tui_config_inputs(cli)?;
+    let config = load_config(cli_kv_overrides, config_overrides).await?;
+
+    Ok(config.features.enabled(Feature::TuiAppServer))
+}
+
+pub async fn should_use_app_server_tui(cli: &Cli) -> std::io::Result<bool> {
+    should_use_app_server_tui_with(cli, Config::load_with_cli_overrides_and_harness_overrides).await
+}

codex-rs/tui/src/lib.rs

@@ -70,6 +70,7 @@ mod app;
 mod app_backtrack;
 mod app_event;
 mod app_event_sender;
+mod app_server_tui_dispatch;
 mod ascii_animation;
 #[cfg(all(not(target_os = "linux"), feature = "voice-input"))]
 mod audio_device;
@@ -229,6 +230,7 @@ pub mod test_backend;
 use crate::onboarding::onboarding_screen::OnboardingScreenArgs;
 use crate::onboarding::onboarding_screen::run_onboarding_app;
 use crate::tui::Tui;
+pub use app_server_tui_dispatch::should_use_app_server_tui;
 pub use cli::Cli;
 use codex_arg0::Arg0DispatchPaths;
 pub use markdown_render::render_markdown_text;
@@ -1288,6 +1290,7 @@ mod tests {
     use codex_protocol::protocol::SessionMetaLine;
     use codex_protocol::protocol::SessionSource;
     use codex_protocol::protocol::TurnContextItem;
+    use pretty_assertions::assert_eq;
     use serial_test::serial;
     use tempfile::TempDir;
 

codex-rs/tui/src/main.rs

@@ -1,8 +1,11 @@
 use clap::Parser;
 use codex_arg0::Arg0DispatchPaths;
 use codex_arg0::arg0_dispatch_or_else;
+use codex_tui::AppExitInfo;
 use codex_tui::Cli;
+use codex_tui::ExitReason;
 use codex_tui::run_main;
+use codex_tui::update_action::UpdateAction;
 use codex_utils_cli::CliConfigOverrides;
 
 #[derive(Parser, Debug)]
@@ -14,6 +17,65 @@ struct TopCli {
     inner: Cli,
 }
 
+fn into_app_server_cli(cli: Cli) -> codex_tui_app_server::Cli {
+    codex_tui_app_server::Cli {
+        prompt: cli.prompt,
+        images: cli.images,
+        resume_picker: cli.resume_picker,
+        resume_last: cli.resume_last,
+        resume_session_id: cli.resume_session_id,
+        resume_show_all: cli.resume_show_all,
+        fork_picker: cli.fork_picker,
+        fork_last: cli.fork_last,
+        fork_session_id: cli.fork_session_id,
+        fork_show_all: cli.fork_show_all,
+        model: cli.model,
+        oss: cli.oss,
+        oss_provider: cli.oss_provider,
+        config_profile: cli.config_profile,
+        sandbox_mode: cli.sandbox_mode,
+        approval_policy: cli.approval_policy,
+        full_auto: cli.full_auto,
+        dangerously_bypass_approvals_and_sandbox: cli.dangerously_bypass_approvals_and_sandbox,
+        cwd: cli.cwd,
+        web_search: cli.web_search,
+        add_dir: cli.add_dir,
+        no_alt_screen: cli.no_alt_screen,
+        config_overrides: cli.config_overrides,
+    }
+}
+
+fn into_legacy_update_action(
+    action: codex_tui_app_server::update_action::UpdateAction,
+) -> UpdateAction {
+    match action {
+        codex_tui_app_server::update_action::UpdateAction::NpmGlobalLatest => {
+            UpdateAction::NpmGlobalLatest
+        }
+        codex_tui_app_server::update_action::UpdateAction::BunGlobalLatest => {
+            UpdateAction::BunGlobalLatest
+        }
+        codex_tui_app_server::update_action::UpdateAction::BrewUpgrade => UpdateAction::BrewUpgrade,
+    }
+}
+
+fn into_legacy_exit_reason(reason: codex_tui_app_server::ExitReason) -> ExitReason {
+    match reason {
+        codex_tui_app_server::ExitReason::UserRequested => ExitReason::UserRequested,
+        codex_tui_app_server::ExitReason::Fatal(message) => ExitReason::Fatal(message),
+    }
+}
+
+fn into_legacy_exit_info(exit_info: codex_tui_app_server::AppExitInfo) -> AppExitInfo {
+    AppExitInfo {
+        token_usage: exit_info.token_usage,
+        thread_id: exit_info.thread_id,
+        thread_name: exit_info.thread_name,
+        update_action: exit_info.update_action.map(into_legacy_update_action),
+        exit_reason: into_legacy_exit_reason(exit_info.exit_reason),
+    }
+}
+
 fn main() -> anyhow::Result<()> {
     arg0_dispatch_or_else(|arg0_paths: Arg0DispatchPaths| async move {
         let top_cli = TopCli::parse();
@@ -22,12 +84,25 @@ fn main() -> anyhow::Result<()> {
             .config_overrides
             .raw_overrides
             .splice(0..0, top_cli.config_overrides.raw_overrides);
-        let exit_info = run_main(
-            inner,
-            arg0_paths,
-            codex_core::config_loader::LoaderOverrides::default(),
-        )
-        .await?;
+        let use_app_server_tui = codex_tui::should_use_app_server_tui(&inner).await?;
+        let exit_info = if use_app_server_tui {
+            into_legacy_exit_info(
+                codex_tui_app_server::run_main(
+                    into_app_server_cli(inner),
+                    arg0_paths,
+                    codex_core::config_loader::LoaderOverrides::default(),
+                    None,
+                )
+                .await?,
+            )
+        } else {
+            run_main(
+                inner,
+                arg0_paths,
+                codex_core::config_loader::LoaderOverrides::default(),
+            )
+            .await?
+        };
         let token_usage = exit_info.token_usage;
         if !token_usage.is_zero() {
             println!(